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**Revised Level I Screening Ecological Risk Assessment**

**for the Reregistration of Chloropicrin**

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| ***Prepared by:***                     |                             |
+----------------------------------------+-----------------------------+
|                                        |                             |
+----------------------------------------+-----------------------------+
| **Faruque Khan, Environmental          | **U. S. Environmental       |
| Scientist**                            | Protection Agency**         |
|                                        |                             |
| **James Felkel, Wildlife Biologist**   | **Office of Pesticide       |
|                                        | Programs**                  |
|                                        |                             |
|                                        | **Environmental Fate and    |
|                                        | Effects Division**          |
|                                        |                             |
|                                        | **Environmental Risk Branch |
|                                        | IV**                        |
|                                        |                             |
|                                        | **Ariel Rios Building (Mail |
|                                        | Code 7507C)**               |
|                                        |                             |
|                                        | **1200 Pennsylvania Ave.,   |
|                                        | NW**                        |
|                                        |                             |
|                                        | **Washington, DC 20460**    |
+----------------------------------------+-----------------------------+
| ***Reviewed by:***                     |                             |
|                                        |                             |
| **Ron Parker, Environmental Engineer** |                             |
|                                        |                             |
| **Nick Federoff, Wildlife Biologist**  |                             |
|                                        |                             |
| **Jean Holmes, RAPL**                  |                             |
|                                        |                             |
| **Mah Shamim, Branch Chief**           |                             |
+----------------------------------------+-----------------------------+

**Table of Contents**

I. Executive Summary [[1]{.underline}](#Generated)

> A. Nature of Chemical Stressor [[1]{.underline}](#Generated)
>
> B. Conclusions - Exposure Characterization
> [[1]{.underline}](#Generated)
>
> C. Potential Risks to Non-target Organisms
> [[2]{.underline}](#Generated)
>
> D. Conclusions - Effects Characterization
> [[3]{.underline}](#Generated)
>
> E. Data Gaps and Uncertainties [[3]{.underline}](#Generated)
>
> 1\. Environmental Fate and Exposure [[3]{.underline}](#Generated)
>
> 2\. Ecological Effects [[4]{.underline}](#Generated)

II\. Problem Formulation [[7]{.underline}](#Generated)

> A. Stressor Source and Distribution [[7]{.underline}](#Generated)
>
> 1\. Source and Intensity [[7]{.underline}](#Generated)
>
> 2\. Physical/Chemical/Fate and Transport Properties
> [[7]{.underline}](#Generated)
>
> 3\. Pesticide Type, Class, and Mode of Action
> [[7]{.underline}](#Generated)
>
> 4\. Overview of Pesticide Usage [[7]{.underline}](#Generated)
>
> B. Receptors [[8]{.underline}](#Generated)
>
> 1\. Ecological Effects [[8]{.underline}](#Generated)
>
> 2\. Ecosystems Potentially At Risk [[10]{.underline}](#Generated)
>
> C. Assessment Endpoints [[11]{.underline}](#Generated)
>
> D. Conceptual Model [[11]{.underline}](#Generated)
>
> 1\. Risk Hypotheses [[11]{.underline}](#Generated)
>
> 2\. Diagram [[11]{.underline}](#Generated)
>
> E. Analysis Plan [[14]{.underline}](#Generated)
>
> a\. Measures of Exposure [[16]{.underline}](#Generated)
>
> b\. Measures of Effect [[16]{.underline}](#Generated)
>
> c\. Measures of Ecosystem and Receptor Characteristics
> [[17]{.underline}](#Generated)

III\. Analysis [[18]{.underline}](#Generated)

> A. Use Characterization [[18]{.underline}](#Generated)
>
> B. Exposure Characterization [[20]{.underline}](#Generated)
>
> 1\. Environmental Fate and Transport Characterization
> [[20]{.underline}](#Generated)
>
> \(a\) Fate and Transport in soil and water
> [[22]{.underline}](#Generated)
>
> \(b\) Fate and Transport in atmosphere [[23]{.underline}](#Generated)
>
> \(c\) Ozone Depletion Potential [[25]{.underline}](#Generated)
>
> 2\. Measures of Terrestrial Exposure [[25]{.underline}](#Generated)
>
> (a)Terrestrial Exposure Modeling [[25]{.underline}](#Generated)
>
> \(b\) Terrestrial Exposure Monitoring Data
> [[27]{.underline}](#Generated)
>
> 3\. Measures of Aquatic Exposure [[29]{.underline}](#Generated)
>
> a\. Aquatic Exposure Modeling [[29]{.underline}](#Generated)
>
> b\. Aquatic Exposure Monitoring and Field Data
> [[32]{.underline}](#Generated)
>
> C. Ecological Effects Characterization [[32]{.underline}](#Generated)
>
> 1\. Aquatic Effects Characterization [[33]{.underline}](#Generated)
>
> a\. Aquatic Animals [[33]{.underline}](#Generated)
>
> 2\. Terrestrial Effects Characterization
> [[34]{.underline}](#Generated)
>
> a\. Terrestrial Animals [[34]{.underline}](#Generated)

IV\. Risk Characterization [[36]{.underline}](#Generated)

> A. Risk Estimation - Integration of Exposure and Effects Data
> [[36]{.underline}](#Generated)
>
> 1\. Non-target Aquatic Animals and Plants
> [[36]{.underline}](#Generated)
>
> 2\. Non-target Terrestrial Animals [[37]{.underline}](#Generated)
>
> a\. Risk to Mammals [[37]{.underline}](#Generated)
>
> b\. Risk to Avian Species [[38]{.underline}](#Generated)
>
> 3\. Non-target Terrestrial and Semi-aquatic Plants
> [[38]{.underline}](#Generated)
>
> B. Risk Description [[39]{.underline}](#Generated)
>
> 1\. Risk to Aquatic Organisms [[39]{.underline}](#Generated)
>
> A. Animals [[39]{.underline}](#Generated)
>
> B. Plants [[40]{.underline}](#Generated)
>
> *2. Risk to Terrestrial Organisms* [[40]{.underline}](#Generated)
>
> A. Animals [[40]{.underline}](#Generated)
>
> B. Plants [[42]{.underline}](#Generated)
>
> 3\. Review of Incident Data [[42]{.underline}](#Generated)
>
> 4\. Endocrine Disruption [[43]{.underline}](#Generated)
>
> 5\. Federally Threatened and Endangered (Listed) Species Concerns
> [[44]{.underline}](#Generated)
>
> A. Action Area [[44]{.underline}](#Generated)
>
> B. Taxonomic Groups Potentially at Risk [[44]{.underline}](#Generated)
>
> 1\. Discussion of Risk Quotients [[45]{.underline}](#Generated)
>
> 2\. Probit Dose Response Relationship [[45]{.underline}](#Generated)
>
> C. Data Related to Under-represented Taxa
> [[46]{.underline}](#Generated)
>
> D. Implications of Sublethal Effects [[46]{.underline}](#Generated)
>
> E. Indirect Effects Analysis [[46]{.underline}](#Generated)
>
> F. Critical Habitat [[47]{.underline}](#Generated)
>
> G. Co-occurrence Analysis [[48]{.underline}](#Generated)

V. Literature Cited [[49]{.underline}](#Generated)

VI\. Appendices [[54]{.underline}](#Generated)

> Appendix A. Environmental Fate and Transport Data
> [[54]{.underline}](#Generated)
>
> Appendix B. Aquatic Exposure PRZM/EXAMS Modeling
> [[62]{.underline}](#Generated)
>
> Appendix C: Ecological Effects Data [[83]{.underline}](#Generated)
>
> a\. Toxicity to Terrestrial Animals [[83]{.underline}](#Generated)
>
> i\. Birds, Acute and Subacute [[83]{.underline}](#Generated)
>
> ii\. Birds, Chronic [[84]{.underline}](#Generated)
>
> iii\. Mammalian Toxicity Data (from HED)
> [[84]{.underline}](#Generated)
>
> b\. Toxicity to Freshwater Aquatic Animals
> [[91]{.underline}](#Generated)
>
> i\. Freshwater Fish, Acute [[91]{.underline}](#Generated)
>
> ii\. Freshwater Fish, Chronic [[91]{.underline}](#Generated)
>
> \(iii\) Freshwater Invertebrates, Acute [[92]{.underline}](#Generated)
>
> iv\. Freshwater Invertebrate, Chronic [[92]{.underline}](#Generated)
>
> c\. Toxicity to Estuarine and Marine Animals
> [[92]{.underline}](#Generated)
>
> i\. Estuarine and Marine Fish, Acute [[92]{.underline}](#Generated)
>
> ii\. Estuarine and Marine Fish, Chronic [[93]{.underline}](#Generated)
>
> iii\. Estuarine and Marine Invertebrates, Acute
> [[93]{.underline}](#Generated)
>
> iv\. Estuarine and Marine Invertebrate, Chronic
> [[93]{.underline}](#Generated)
>
> d\. Toxicity to Plants [[93]{.underline}](#Generated)
>
> i\. Terrestrial Plants [[93]{.underline}](#Generated)
>
> ii\. Aquatic Plants [[93]{.underline}](#Generated)
>
> Appendix D. The Risk Quotient Method and Levels of Concern
> [[95]{.underline}](#Generated)

Appendix E. Data Requirement Tables [[97]{.underline}](#Generated)

**CONVERSION FACTORS**

To convert concentrations in air (at 25 °C) from ppm to mg/m^3^: mg/m^3^
= (ppm) ×(molecular weight of the compound)/(24.45).

**I. Executive Summary**

**A. Nature of Chemical Stressor**

Chloropicrin, a pre-plant soil fumigant is used in controlling a broad
range of soil pathogens. It is a clear, colorless, nonflammable oily
liquid with strong, sharp, highly irritating odor and is a strong
lacrimator (tear-producer). Chloropicrin's specific mode of action is
not understood, but it is a strong irritant that is very toxic to all
biological systems; affecting body surfaces and interfering with the
respiratory system and the cellular transport of oxygen (U.S. Forest
Service, 1995). Chloropicrin is typically applied once per growing
season through soil injection or drip irrigation to fumigate the upper
six to twelve inches of soil as a liquid 14 days or more before
planting. The maximum application rate is 350 lbs ai/A, with 300 lbs
ai/A the maximum for drip irrigation.

**B. Conclusions - Exposure Characterization**

The high vapor pressure (23.8 mm @ 25^○^C), high Henry's Law Constant
(2.05 X 10^-3^ atm M^3^/mole), and low affinity for sorption (K~oc~
36.05 L kg^-1^) on soil of chloropicrin suggest that volatilization is
the most important environmental route of dissipation. The importance of
other competing environmental processes such as leaching, biotic and
abiotic degradation, and adsorption to the soil particles will certainly
depend on the chloropicrin emission rate, weather conditions, and soil
characteristics of the fumigated fields. Fumigant post-application field
management practices like splitting, retaining or removing tarp from the
fumigated field also determine the amount of chloropicrin that will be
available for other competing environmental processes and its residence
time in soil. The estimated biodegradation half-lives of chloropicrin in
soil range from 4.5 to 10 days, with carbon dioxide being the terminal
breakdown product.

Once it volatilized, chloropicrin photolyzes rapidly with an estimated
atmospheric half-life of 3.4 to 8 hours in direct sunlight, leading to
an estimate of 1 day for its atmospheric lifetime. With an ozone
depletion potential more than four orders of magnitude (5.6x10^-5^
versus 0.38) less than the ozone depleting substances such as methyl
bromide, chloropicrin is not a threat to stratospheric ozone. The major
degradation products were phosgene (carbonyl chloride) and nitrosyl
chloride, which rapidly photolyzes to reactive products NO and Cl•.
Continued oxidation of the chloropicrin photolysis products would
eventually produce CO~2~, NO~2~, N~2~O~4~, and Cl~2~. The reactive
byproducts of chloropicrin photolysis, in particular chlorine free
radicals and NO~x~, could lead to the generation of tropospheric ozone.
Since the metabolites of chloropinrin are very reactive and unstable in
the atmosphere, they were not considered in the risk assessment.

Since chloropicrin is highly soluble in water and has low adsorption in
soil, residual chloropicrin in soil can potentially leach into
groundwater under continuos irrigation and high rainfall events and to
surface water through runoff under a flooded condition. The calculated
half-life of 31.1 hours is for chloropicrin in aqueous solution (pH 7)
when irradiated with a xenon light source, forming carbon dioxide,
chloride, nitrate and nitrite. The high Henry's Law Constant (2.05 X
10^-3^ atm M^3^/mole) and rapid photohydrolysis of chloropicrin suggest
that volatilization and rapid abiotic degradation are the most important
routes of dissipation from surface water. Also, the low octanol/water
partition coefficient of chloropicrin indicates that it is not likely to
be bioconcentrated in tissues of aquatic organisms. Chloropicrin was
found at less than 1.00 μg/L in three wells from 15,175 wells in
Florida. However, no monitoring data of chloropicrin in surface water
are available at the present time.

**C. Potential Risks to Non-target Organisms**

This is a Level I screening assessment. EFED has a strong presumption of
acute risk to all exposed plants and animals, since chloropicrin is a
broad-spectrum fumigant. It is assumed that all living organisms in the
treated soil (including beneficial insects and burrowing mammals, for
example) are at high risk of mortality. In addition, a wide range of
terrestrial and aquatic non-target organisms off-site may also be at
risk. Chloropicrin appears to pose risks to mammals and birds based on
modeled air residues, exceeding an equivalent acute Level of Concern
(LOC) for endangered species. It also exceeds LOCs (including acute
endangered species) for fish with all modeled scenarios and for aquatic
invertebrates for three of six scenarios. However, there are substantial
uncertainties in estimating ecological effects of chloropicrin due to
limited toxicity data and the limitations of current exposure models and
crop scenarios. The PRZM model also has limited capabilities in
capturing the partitions of volatile chemical in air, water and
sediment. No fully acceptable toxicity data are available, except for
the mammal acute oral and chronic inhalation data used, and thus
uncertainty levels are high.

**[Risks to Aquatic Animals]{.underline}**

Of the six modeled scenarios, chloropicrin exceeds Levels-of-Concern
(acute endangered species, acute restricted use, and/or acute risk) 1)
for fish, with all six scenarios (California tomatoes, California
onions, Florida tomatoes, Florida strawberries, North Carolina sweet
potatoes, and North Carolina tobacco; risk quotients range from \>0.09
to \>6.35), and 2) for aquatic invertebrates, with California tomatoes,
Florida tomatoes and Florida strawberries (risk quotients range from
\>0.05 to \>1.52 for these crops). Since all toxicity values are
considered to be less than the calculated numeric values (because of
absent or inadequately measured residues of this volatile chemical),
risk quotients are all expressed as greater than the quotient numeric
values. EFED thus cannot confirm that any use pattern does not exceed
LOCs. Some mortality occurred in the aquatic invertebrate study even at
test levels where residues were below the Level of Quantitation at 48
hours. Thus, the above use sites are simply examples of sites that would
exceed one or more LOCs even if the actual toxicity values were not
lower (i.e., more toxic) than the values used for the risk quotient
calculations. These risks would also apply to other aquatic animals such
as aquatic phase amphibians. However, in addition to this uncertainty
concerning the toxicity of chloropicrin to aquatic animals (i.e., with
toxicity values expressed as less than the calculated values, EFED
considers chloropicrin to be more toxic than these values), there are
also substantial uncertainties concerning exposure modeling values, as
described below (in Data Gaps and Uncertainties).

**[Risks to Terrestrial Animals]{.underline}**

The risk to non-target terrestrial animals off-site is primarily from
inhalation of chloropicrin off-gassed from treated fields. EFED does not
have LOCs specifically for inhalation exposure. However, based on
modeled air residues and acute toxicity data available from Health
Effects Division, chloropicrin would exceed the existing LOCs for acute
risk to endangered species for mammals. Based on the mammal analysis, it
is assumed that birds could be at a similar risk. Other terrestrial
wildlife (e.g., reptiles and terrestrial phase amphibians) may also be
at risk.

**[Risks to Aquatic and Terrestrial Plants]{.underline}**

Although no guideline plant data are available for chloropicrin, label
and other information citing phytotoxicity potential on treated sites
implies that off-gassed chloropicrin might also pose a risk to
terrestrial plants and that modeled aquatic residues might pose a risk
to aquatic plants.

**D. Conclusions - Effects Characterization**

Based on very limited data, chloropicrin is considered very highly toxic
to both fish (lowest LC50 \< 16.98 ppb) and aquatic invertebrates
(lowest LC50 \< 71 ppb). The acute mammal inhalation LD50 is 0.114 mg/L
(male rats) and the developmental NOAEL in rabbits is 0.003 mg/L (LOAEL
0.008 mg/L, based on abortions and decreased fetal weights). The mammal
acute oral LD50 value (used in a preliminary analysis) is 37.5 mg/kg
(highly toxic).

**E. Data Gaps and Uncertainties**

**1. Environmental Fate and Exposure**

The environmental fate data base for the parent compound provided mostly
supplemental information (Appendix F, Table A1-B). However, key
environmental fate studies such as aerobic soil metabolism and
photolysis in air have several deficiencies and problems. Therefore,
data related to these key environmental fate processes were also
obtained from open literature to complete the environmental fate and
exposure assessment. The following environmental fate study was not
submitted, but is not needed for risk assessment.

[165-4 Bioaccumulation in fish of chloropicrin]{.underline} The
octanol/water partition coefficient (Log K~ow~) for chloropicrin is
2.38, indicating a low potential for chloropicrin to bioaccumulate in
aquatic organisms. It also photolyzed (t~1/2~= 1.3 days) in water
rapidly. The bioaccumulation in fish study is not required under these
circumstances, according to the Subdivision N guidelines.

> ***Uncertainties***

There are uncertainties in estimating chloropicrin exposure in surface
water from post-application, due to tarping of the treated area. If
tarping is used to minimize the volatilization of chloropicrin, the
loading of the chemical through runoff will be limited until the tarp is
sliced or removed from the field. The present version of the PRZM model
and the selected crop scenarios used in modeling have limited
capabilities in discounting the load from runoff of applied chemical
under a post-application tarp scenario. PRZM also has limited
capabilities in capturing the partitions of a volatile chemical in air,
water and sediment. Since the load of chloropicrin from runoff is
considered in the PRZM/EXAMS simulation, the estimated concentrations of
chloropicrin in surface water bodies may be upper bound.

There are uncertainties with both existing monitoring and modeling of
air residues for the purpose of estimating exposure to terrestrial
wildlife. Since field emission and air monitoring data of chloropicrin
were collected greater than 1 meter above the ground surface, actual
concentrations at ground level may differ from estimated air
concentration using ISCTS3 modeling and ambient air monitoring . Air
monitoring at ground-level of chloropicrin in the fumigated fields may
reduce the uncertainty related to terrestrial exposure for wildlife.

**2. Ecological Effects**

The following data are needed on chloropicrin for ecological risk
assessment. These data needs are similar to those available or
previously specified as needed for risk assessment for methyl bromide
and for the degradate MITC as part of the metam-sodium risk assessment.
Appendix E lists the status of the ecological effects data requirements
for chloropicrin.

[71-1 Avian Acute Oral]{.underline}. The current estimate of avian risk
is based largely on the mammal assessment. This basic study will
contribute to a risk assessment specific to birds. It will 1) enable a
comparison to the mammal acute oral data and 2) enable the use of an
EFED spreadsheet to estimate avian acute inhalation toxicity based on
the mammal acute oral and inhalation data.

[\-\-\-\-- Avian acute inhalation]{.underline}. The current estimate of
avian risk is based largely on the mammal assessment. This study will
enable an inhalation risk assessment specific to birds. Since the risk
assessment for terrestrial wildlife is focused on inhalation and this
study will provide actual inhalation data rather than an estimation
based on acute oral data, it is of even higher priority than the acute
oral study.

[\-\-\-\--Avian sub-chronic/chronic inhalation]{.underline}. This study
is needed for risk assessment, due to the potential for repeat and/or
continuous exposure to birds resulting from the use of chloropicrin on
multiple fields over multiple days in any given geographic area.

[870.1300. Acute inhalation toxicity test -- rat.]{.underline}. The
existing study (MRID 45117902) is classified by HED as
Acceptable/Non-guideline. The 7/25/00 DER and 1/31/05 Revised HED Human
Health Risk Assessment state: "The LC50 calculated for the study should
not be considered to be a true LC50 for chloropicrin. Due to the
sacrifice of all live animals at day 3 of the study instead of day 14,
and too large of exposure particle sizes, the true LC50 could be lower."
Thus, a new study will enable an improved wild mammal risk assessment
with reduced uncertainty. Please note that although EFED needs the
results this study for risk assessment, it is not listed in Appendix E
since it is an HED guideline and EFED does not review these studies.

[72-1(a) and (c) Acute Fish Toxicity -- bluegill and rainbow
trout.]{.underline} The risk assessment is currently relying on
supplemental data, with indeterminate toxicity values. Flow-through
studies with measured concentrations will greatly reduce uncertainty.

[72-2(a) Acute aquatic invertebrate toxicity.]{.underline} The risk
assessment is currently relying on supplemental data, with indeterminate
toxicity values. Flow-through studies with measured concentrations will
greatly reduce uncertainty.

[72-3(a) Acute Marine/Estuarine Fish]{.underline}. Given the use
patterns of chloropicrin, marine/estuarine species could be exposed.
This study will enable a risk assessment specific for marine/estuarine
species exposure.

[72-3(b) Acute Marine/Estuarine Mollusk]{.underline}. Given the use
patterns of chloropicrin, marine/estuarine species could be exposed.
This study will enable a risk assessment specific for marine/estuarine
species exposure. It will also improve certainty with the endangered
species risk assessment, as this test species may be more representative
of endangered freshwater mussels than the freshwater *Daphnia*.

[72-3 (c) Acute Marine/Estuarine Shrimp]{.underline}. Given the use
patterns of chloropicrin, marine/estuarine species could be exposed.
This study will enable a risk assessment specific for marine/estuarine
species exposure. One literature search toxicity value is available, but
it is from a static study without measured concentrations.

[72-4(a) Early Life-stage Fish -- Freshwater]{.underline}. Current
aquatic modeling indicates the potential for chronic aquatic exposure to
chloropicrin. This study will enable a chronic risk assessment for
freshwater fish.

[72-4(a) Early Life-stage Fish -- Marine/Estuarine]{.underline}. Current
aquatic modeling indicates the potential for chronic aquatic exposure to
chloropicrin. This study is reserved pending the submission and review
of the above early life-stage studies with a freshwater fish species.

[72-4(b) Life-Cycle Aquatic Invertebrate]{.underline}. Current aquatic
modeling indicates the potential for chronic aquatic exposure to
chloropicrin. This study will enable a chronic risk assessment for
aquatic invertebrates.

[72-5 Life-Cycle Fish]{.underline}. This study is reserved, pending
submission and review of early life-stage fish testing.

[123-1(a) Seed Germination/Seedling Emergence -- Tier II]{.underline}.
Chloropicrin is used in part due to its phytotoxicity at the application
site, and a wide range of open literature and other non-guideline
studies indicate the potential for plant damage. This study will enable
the assessment of risk to non-target terrestrial plants off-site.

[123-1(b) Vegetative Vigor -- Tier II]{.underline}. Chloropicrin has at
least some phytotoxicity on the treatment site, based on label and open
literature information. This study will enable the assessment of risk to
non-target terrestrial plants off-site.

[123-2 Aquatic Plant Growth -- Tier II]{.underline}. Chloropicrin has at
least some phytotoxicity on the treatment site, based on label and open
literature information. This study will enable the assessment of risk to
non-target aquatic plants off-site.

[141-1 Honeybee Acute contact.]{.underline} This basic study is now
being requested for virtually all outdoor uses, and will help determine
the need for, and specifics of, bee hazard labeling.

***Uncertainties***

There are substantial uncertainties concerning the ecological effects of
chloropicrin, in part due to the extremely limited data available for
risk assessment. There are no studies considered fully acceptable for
any taxonomic group or time exposure, except for the mammal acute oral
and chronic inhalation data used.

The uncertainties associated with the risk to terrestrial organisms from
chloropicrin use are mainly focused on the extent and effect of
terrestrial animal exposure via inhalation. There is uncertainty with
the mammal acute inhalation toxicity, as indicated above. Avian
inhalation toxicity data are not available at all, as also noted. In
addition, the lack of avian acute oral data prevents an extrapolated
estimation of inhalation toxicity based on mammal data. Terrestrial
plant data are needed to conduct an assessment of risk to non-target
terrestrial plants off-site.

Because of the repeat exposures from applications to different fields on
different days in a given geographic area, there is the added potential
for chronic exposure. Acute inhalation studies are typically just 4
hours long. A subchronic/chronic avian inhalation study will enable EFED
to address longer-term exposure to birds.

The uncertainties associated with the risk to aquatic organisms from
chloropicrin are due to uncertainties over the length of exposure to
this highly volatile chemical and to uncertainties over the toxicity
(resulting mainly from the volatility). However, both acute and chronic
exposure are possible, in part due to repeat or continuous input to the
aquatic environment. Acute and chronic toxicity data are not available
for most fish and aquatic invertebrate guideline test categories,
freshwater or estuarine/marine. The risk assessment relies on
supplemental data for freshwater fish and aquatic invertebrates.

II\. Problem Formulation

A. Stressor Source and Distribution

1\. Source and Intensity

The source of the stressor considered in this ecological risk assessment
is the sole active ingredient chloropicrin, a pre-plant fumigant used in
controlling soil pathogens. Chloropicrin is a small, single-carbon
organic molecule that diffuses rapidly and volatilizes from applied
agricultural soils. The major source and mechanism of release of
chloropicrin is volatilization from the fumigated sites. Additional
transport mechanisms include runoff from pre-plant fumigated fields, and
drift of volatilized chloropicrin and redeposition through precipitation
in the adjacent area. The major breakdown products of chloropicrin in
soil and air is carbon dioxide. Since the degradation products of
chloropicrin are unstable in the environment, no metabolites were
considered in the risk assessment.

***2. Physical/Chemical/Fate and Transport Properties***

Chloropicrin is a clear, colorless, nonflammable oily liquid with
strong, sharp, highly irritating odor and a strong lacrimator. The high
vapor pressure (23.8 mm @ 25^○^C), high Henry's Law Constant (2.05 \*
10^-3^ atm M^3^/mole), and low affinity for sorption on soil of
chloropicrin suggest that volatilization is the most important
environmental route of dissipation. Chloropicrin also undergoes rapid
breakdown in soil, primarily via microbial degradation as well as in the
atmosphere through direct photolysis. The relatively low K~ow~ and high
water solubility of the parent suggests bio-concentration in aquatic
organisms will be low.

***3. Pesticide Type, Class, and Mode of Action***

Chloropicrin is a fumigant used in pre-plant soil fumigation.
Chloropicrin's specific mode of action is not understood, but it is a
strong irritant that is very toxic to all biological systems; affecting
body surfaces and interfering with the respiratory system and the
cellular transport of oxygen (U.S. Forest Service, 1995).

***4. Overview of Pesticide Usage***

Pre-plant soil use in agriculture accounts for most of the use of
chloropicrin. Chloropicrin can also be formulated in combination with
other fumigant to broaden its spectrum. In these combination end-use
products, the percent active ingredient for chloropicrin can range from
20 to 55% when combined with methyl bromide and from 15 to 60% when
combined with 1,3-D. Chloropicrin is typically applied once per growing
season through soil injection or drip irrigation to fumigate upper six
to twelve inches of soil as a liquid 14 days or more before planting.
The maximum application rate is 350 lb ai/A, with 300 lb ai/A the
maximum for drip irrigation. The product is also used as a warning agent
for odorless fumigants. Individually, strawberries, tobacco, tomatoes,
and peppers were the crops with the highest percentage of their overall
acreage treated from 1998 to 2000.

**B. Receptors**

**1. Ecological Effects**

Each assessment endpoint requires one or more measures of ecological
effect, which are defined as changes in the attributes of an assessment
endpoint itself or changes in a surrogate entity or attribute in
response to exposure to a pesticide. Ecological measures of effect for
the screening level risk assessment are usually based on a suite of
registrant-submitted toxicity studies performed on a limited number of
organisms in broad groupings listed in **Table 1**. These laboratory
test organisms serve as surrogates for all nontarget animal and plant
species that could potentially be exposed to a given pesticide.

+----------------------+-----------------------------------------------+
| ***Table 1. Examples |                                               |
| of taxonomic groups  |                                               |
| and test species     |                                               |
| evaluated for        |                                               |
| ecological effects   |                                               |
| in screening level   |                                               |
| risk assessments.*** |                                               |
+----------------------+-----------------------------------------------+
| ***Taxonomic         | ***Example(s) of Representative Species***    |
| Group***             |                                               |
+----------------------+-----------------------------------------------+
| *Birds^1^*           | *mallard duck (Anas playtrhynchos)*           |
|                      |                                               |
|                      | *bobwhite quail (Colinus virginianus)*        |
+----------------------+-----------------------------------------------+
| *Mammals*            | *laboratory rat*                              |
+----------------------+-----------------------------------------------+
| *Freshwater Fish^2^* | *bluegill sunfish (Lepomis macrochirus)*      |
|                      |                                               |
|                      | *rainbow trout (Oncorhynchus mykiss)*         |
+----------------------+-----------------------------------------------+
| *Freshwater          | *water flea (Daphnia magna)*                  |
| Invertebrates*       |                                               |
+----------------------+-----------------------------------------------+
| *Estuarine/Marine    | *sheepshead minnow (Cypridodon variegatus)*   |
| Fish*                |                                               |
+----------------------+-----------------------------------------------+
| *Estuarine/Marine    | *Eastern Oyster (Crassostrea virginica)*      |
| Invertebrates*       |                                               |
|                      | *Mysid Shrimp (Americamysis bahia)*           |
+----------------------+-----------------------------------------------+
| *Terrestrial         | *Monocots - corn (Zea mays)*                  |
| Plants^3^*           |                                               |
|                      | *Dicots - soybean (Glycine max)*              |
+----------------------+-----------------------------------------------+
| *Aquatic Plants and  | *duckweed (Lemna gibba)*                      |
| Algae*               |                                               |
|                      | *green algae (Selenastrum capricornutum)*     |
+----------------------+-----------------------------------------------+
| *^1^ Birds may be    |                                               |
| surrogates for       |                                               |
| amphibians           |                                               |
| (terrestrial phase)  |                                               |
| and reptiles.*       |                                               |
|                      |                                               |
| *^2^ Freshwater fish |                                               |
| may be surrogates    |                                               |
| for amphibians       |                                               |
| (aquatic phase).*    |                                               |
|                      |                                               |
| *^3^ Four species of |                                               |
| two families of      |                                               |
| monocots, of which   |                                               |
| one is corn; six     |                                               |
| species of at least  |                                               |
| four dicot families, |                                               |
| of which one is      |                                               |
| soybeans.*           |                                               |
+----------------------+-----------------------------------------------+

Within each of these very broad taxonomic groups, an acute and/or
chronic endpoint is selected from the available test data. A complete
discussion of all toxicity data available for this risk assessment and
the resulting measures of effect selected for each taxonomic group are
included in Appendix C. A summary of the potential assessment endpoints
and measures of effect selected to characterize potential ecological
risks associated with exposure to chloropicrin is provided in **Table
2**. However, data are not available for all potential measures of
effect.

+---+---------------------------+---+-----------------------------------+
| * |                           |   |                                   |
| * |                           |   |                                   |
| T |                           |   |                                   |
| a |                           |   |                                   |
| b |                           |   |                                   |
| l |                           |   |                                   |
| e |                           |   |                                   |
| 2 |                           |   |                                   |
| . |                           |   |                                   |
| S |                           |   |                                   |
| u |                           |   |                                   |
| m |                           |   |                                   |
| m |                           |   |                                   |
| a |                           |   |                                   |
| r |                           |   |                                   |
| y |                           |   |                                   |
| o |                           |   |                                   |
| f |                           |   |                                   |
| p |                           |   |                                   |
| o |                           |   |                                   |
| t |                           |   |                                   |
| e |                           |   |                                   |
| n |                           |   |                                   |
| t |                           |   |                                   |
| i |                           |   |                                   |
| a |                           |   |                                   |
| l |                           |   |                                   |
| a |                           |   |                                   |
| s |                           |   |                                   |
| s |                           |   |                                   |
| e |                           |   |                                   |
| s |                           |   |                                   |
| s |                           |   |                                   |
| m |                           |   |                                   |
| e |                           |   |                                   |
| n |                           |   |                                   |
| t |                           |   |                                   |
| e |                           |   |                                   |
| n |                           |   |                                   |
| d |                           |   |                                   |
| p |                           |   |                                   |
| o |                           |   |                                   |
| i |                           |   |                                   |
| n |                           |   |                                   |
| t |                           |   |                                   |
| s |                           |   |                                   |
| a |                           |   |                                   |
| n |                           |   |                                   |
| d |                           |   |                                   |
| m |                           |   |                                   |
| e |                           |   |                                   |
| a |                           |   |                                   |
| s |                           |   |                                   |
| u |                           |   |                                   |
| r |                           |   |                                   |
| e |                           |   |                                   |
| s |                           |   |                                   |
| o |                           |   |                                   |
| f |                           |   |                                   |
| e |                           |   |                                   |
| f |                           |   |                                   |
| f |                           |   |                                   |
| e |                           |   |                                   |
| c |                           |   |                                   |
| t |                           |   |                                   |
| . |                           |   |                                   |
| * |                           |   |                                   |
| * |                           |   |                                   |
+===+===========================+===+===================================+
| * |                           | * |                                   |
| * |                           | * |                                   |
| A |                           | M |                                   |
| s |                           | e |                                   |
| s |                           | a |                                   |
| e |                           | s |                                   |
| s |                           | u |                                   |
| s |                           | r |                                   |
| m |                           | e |                                   |
| e |                           | s |                                   |
| n |                           | o |                                   |
| t |                           | f |                                   |
| E |                           | E |                                   |
| n |                           | f |                                   |
| d |                           | f |                                   |
| p |                           | e |                                   |
| o |                           | c |                                   |
| i |                           | t |                                   |
| n |                           | * |                                   |
| t |                           | * |                                   |
| * |                           |   |                                   |
| * |                           |   |                                   |
+---+---------------------------+---+-----------------------------------+
| 1 | Abundance (i.e.,          | 1 | Bobwhite quail or mallard duck    |
| \ | survival, reproduction,   | a | acute oral LD~50~                 |
| . | and growth) of            | . |                                   |
|   | individuals and           |   |                                   |
|   | populations of birds      |   |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 1 | Bobwhite quail and mallard duck   |
|   |                           | b | subacute dietary LC~50~           |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 1 | Bobwhite quail or mallard duck    |
|   |                           | c | acute inhalation LC~50~           |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 1 | Bobwhite quail and mallard duck   |
|   |                           | d | chronic reproduction NOAEL and    |
|   |                           | . | LOAEL                             |
+---+---------------------------+---+-----------------------------------+
|   |                           | 1 | Bobwhite quail or mallard duck    |
|   |                           | e | sub-chronic/chronic inhalation    |
|   |                           | . | toxicity                          |
+---+---------------------------+---+-----------------------------------+
| 2 | Abundance (i.e.,          | 2 | Laboratory rat acute oral LD~50~  |
| \ | survival, reproduction,   | a |                                   |
| . | and growth) of            | . |                                   |
|   | individuals and           |   |                                   |
|   | populations of mammals    |   |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 2 | Laboratory rat acute inhalation   |
|   |                           | b | toxicity                          |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 2 | Laboratory rat developmental and  |
|   |                           | c | chronic (2-generation) NOAEL and  |
|   |                           | . | LOAEL                             |
+---+---------------------------+---+-----------------------------------+
|   |                           | 2 | Laboratory mammal chronic         |
|   |                           | d | inhalation NOAEL and LOAEL        |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
| 3 | Survival and reproduction | 3 | Rainbow trout and bluegill        |
| \ | of individuals and        | a | sunfish acute LC~50~              |
| . | communities of freshwater | . |                                   |
|   | fish and invertebrates    |   |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 3 | Rainbow trout chronic             |
|   |                           | b | (early-life) NOAEL and LOAEL      |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 3 | Water flea (and other freshwater  |
|   |                           | c | invertebrates) acute EC~50~       |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 3 | Water flea chronic (life-cycle)   |
|   |                           | d | NOAEL and LOAEL                   |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
| 4 | Survival and reproduction | 4 | Sheepshead minnow acute LC~50~    |
| \ | of individuals and        | a |                                   |
| . | communities of            | . |                                   |
|   | estuarine/marine fish and |   |                                   |
|   | invertebrates             |   |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 4 | Estimated chronic NOAEL and LOAEL |
|   |                           | b | values based on the               |
|   |                           | . | acute-to-chronic ratio for        |
|   |                           |   | freshwater fish                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 4 | Eastern oyster and mysid shrimp   |
|   |                           | c | acute LC~50~                      |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 4 | Mysid shrimp chronic (life-cycle) |
|   |                           | d | NOAEL and LOAEL                   |
|   |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
|   |                           | 4 | Estimated NOAEL and LOAEL values  |
|   |                           | e | for mollusks based on the         |
|   |                           | . | acute-to-chronic ratio for mysids |
+---+---------------------------+---+-----------------------------------+
| 5 | Perpetuation of           | 5 | Monocot and dicot seedling        |
| \ | individuals and           | a | emergence and vegetative vigor    |
| . | populations of non-target | . | EC~25~ values                     |
|   | terrestrial and           |   |                                   |
|   | semi-aquatic species      |   |                                   |
|   | (crops and non-crop plant |   |                                   |
|   | species)                  |   |                                   |
+---+---------------------------+---+-----------------------------------+
| 6 | Survival of beneficial    | 6 | Honeybee acute contact LD~50~     |
| \ | insect populations        | a |                                   |
| . |                           | . |                                   |
+---+---------------------------+---+-----------------------------------+
| 7 | Maintenance and growth of | 7 | Algal and vascular plant (i.e.,   |
| \ | individuals and           | a | duckweed) EC~50~ values for       |
| . | populations of aquatic    | . | growth rate and biomass           |
|   | plants from standing crop |   | measurements                      |
|   | or biomass                |   |                                   |
+---+---------------------------+---+-----------------------------------+
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| . |                           |   |                                   |
+---+---------------------------+---+-----------------------------------+

***2. Ecosystems Potentially At Risk***

Ecosystems potentially at risk are expressed in terms of the selected
assessment endpoints. The typical assessment endpoints for
screening-level pesticide ecological risks are reduced survival, and
reproductive and growth impairment for both aquatic and terrestrial
animal species. Aquatic animal species of potential concern include
freshwater fish and invertebrates, estuarine/marine fish and
invertebrates, and amphibians. Terrestrial animal species of potential
concern include birds, mammals, beneficial insects, and earthworms. For
both aquatic and terrestrial animal species, direct acute and direct
chronic exposures are considered. In order to protect threatened and
endangered species, all assessment endpoints are measured at the
individual level, which may also provide insights regarding risks at
higher levels of biological organization (e.g., populations and
communities). For example, pesticide effects on individual survivorship
can have important implications for both population growth rates and
habitat carrying capacity.

For terrestrial plants and plants in semi-aquatic environments, the
screening assessment endpoint is the perpetuation of populations of
non-target species, including crops and non-crop plant species. Existing
testing requirements focus on an evaluation of seedling emergence and
vegetative vigor. The Agency recognizes that these endpoints may not
address all components of the lifecycle of plants in terrestrial and
semi-aquatic environments. It is assumed that impacts at emergence and
in active growth stages can reduce a plant's overall ability to be
competitive, ultimately impacting reproductive success.

For aquatic plants, the assessment endpoint is the maintenance and
growth of standing crop or biomass. Measures of effect for these
assessment endpoints include growth rates and biomass measurements of
algae and common vascular plants (i.e., duckweed). These receptors are
useful indicators of risks to the ecosystem for at least two reasons: 1)
complete exposure pathways exist for these receptors; and 2) they are
ubiquitous, potentially inhabiting areas where pesticides are applied,
or areas where runoff and/or spray drift may occur.

Specifically for chloropicrin, ecosystems potentially at risk would
include those in close enough proximity to treated fields to receive
either off-gassed chloropicrin transported via the air or chloropicrin
transported via ground or surface water. Given the use of chloropicrin
in multiple states and regions across the U.S. (See Figure 2), this
could potentially include a wide variety of terrestrial and aquatic
ecosystems

C. Assessment Endpoints

Assessment endpoints are defined as "explicit expressions of the actual
environmental value that is to be protected." Defining an assessment
endpoint involves two steps: 1) identifying the valued attributes of the
environment that are considered to be at risk; and 2) operationally
defining the assessment endpoint in terms of an ecological entity (i.e.,
a community of fish and aquatic invertebrates) and its attributes (i.e.,
survival and reproduction). Therefore, selection of the assessment
endpoints is based on valued entities (i.e., ecological receptors), the
ecosystems potentially at risk, the migration pathways of pesticides,
and the routes by which ecological receptors are exposed to
pesticide-related contamination. The selection of clearly defined
assessment endpoints is important because they provide direction and
boundaries in the risk assessment for addressing risk management issues
of concern. Potential assessment endpoints and measures of effect are
described in **Table 2**.

**D. Conceptual Model**

***1. Risk Hypotheses***

Risk hypotheses are specific assumptions about potential adverse effects
(i.e., changes in assessment endpoints) and may be based on theory and
logic, empirical data, mathematical models, or probability models (USEPA
1998a). For this assessment, the risk is stressor-initiated, where the
stressor is the release of chloropicrin to the environment. The
following risk hypothesis is presumed for this screening level
assessment:

> *Based on the toxicity, the high application rates, the volatility,
> and the environmental fate and mode of action of chloropicrin, as well
> as the exposed aquatic and terrestrial ecosystems, chloropicrin has
> the potential to cause reduced survival, and reproductive and growth
> impairment for both aquatic and terrestrial animal and plant species.*

Adequate protection is defined as protection of growth, reproduction,
and survival of aquatic and terrestrial animal and plant populations,
and individuals of threatened and endangered species, as needed.

2\. Diagram

The conceptual site model is a generic graphic depiction of the risk
hypothesis, and assumes that as a fumigant with a toxic mode of action,
chloropicrin is capable of affecting terrestrial and aquatic organisms
provided that environmental concentrations are sufficiently elevated as
a result of proposed label uses. However, through a preliminary
iterative process of examining fate and effects data, the conceptual
model, i.e., the risk hypothesis, has been refined to reflect the likely
exposure pathways and the organisms that are most relevant and
applicable to this assessment (**Figure 1**). It includes the potential
pesticide or stressor (chloropicrin), the source and/or transport
pathways, abiotic exposure media, exposure point, biological receptor
types, and attribute changes.

In order for a chemical to pose an ecological risk, it must reach
ecological receptors in biologically significant concentrations. An
exposure pathway is the means by which a contaminant moves in the
environment from a source to an ecological receptor. For an ecological
exposure pathway to be complete, it must have a source, a release
mechanism, an environmental transport medium, a point of exposure for
ecological receptors, and a feasible route of exposure. In addition, the
potential mechanisms of transformation (i.e., which degradates may form
in the environment, in which media, and how much) must be known,
especially for a chemical whose metabolites/degradates are of greater
toxicological concern than the parent compound. The assessment of
ecological exposure pathways, therefore, includes an examination of the
sources and potential migration pathways for constituents, and the
determination of potential exposure routes (e.g., ingestion, inhalation,
dermal absorption).

The source and mechanism of release of chloropicrin are volatilization,
drift and runoff from pre-plant fumigated fields for agricultural crops.
Surface water runoff from the areas of application is assumed to follow
topography. Additional transport mechanisms include drift of volatilized
chloropicrin as well as redeposition through precipitation to the
surrounding areas. Chloropicrin exposure to terrestrial animals is
expected primarily through inhalation of chloropicrin and to a lesser
extent by ingestion of contaminated food items such as grass and foliage
contaminated from atmospheric redeposition. Exposure from redeposition
of volatilized chloropicrin via precipitation in terrestrial environment
is expected to be negligible, due to the short direct photolytic
half-life ((t~1/2~ \<8 hrs) of chloropicrin in the atmosphere. Thus, the
exposure from redeposition of chloropicrin via precipitation was not
considered in this assessment.
![](media/image4.emf){width="8.926388888888889in"
height="6.120833333333334in"}

Ecological receptors that may potentially be exposed to chloropicrin
include terrestrial and semi-aquatic wildlife (i.e., mammals, birds, and
reptiles), terrestrial plants and plants in semi-aquatic areas, and soil
invertebrates. In addition to terrestrial ecological receptors, aquatic
receptors (e.g., freshwater and estuarine/marine fish and invertebrates,
amphibians) may also be exposed to potential migration of pesticide from
the site of application to various watersheds and other aquatic
environments via runoff and drift of volatilized material. For aquatic
receptors, the major point of exposure is through direct contact with
the water column, sediment, and pore water (gill/integument)
contaminated with spray drift and/or runoff from treated areas. However,
indirect effects to aquatic organisms (especially fish) can also occur
through impact to various food chains.

There are substantial uncertainties concerning the ecological effects of
chloropicrin, in part due to the extremely limited ecotoxicity data
available. There are no studies considered fully acceptable for any
taxonomic group or time exposure, except the mammal acute oral and
chronic inhalation data used. Therefore, the evaluation of risk to
various taxonomic groups is based on very limited toxicity data.

E. Analysis Plan

> ***1. Preliminary Identification of Data Gaps and Methods***

The analysis plan is the final step in Problem Formulation and targets
the working hypotheses that are considered more likely to effect the
assessment endpoints. The Analysis Plan specifies the data that is
required in developing an evaluation of the potential impact of a
pesticide to the assessment endpoints and the methods that will be used
to analyze the data. The Analysis Plan is also used to outline the scope
of the assessment, identify the measures of effect to be used in
evaluating the hypothesis, and a rationale for the focus and possible
refinement of the assessment.

The objective of EFED's risk assessment is to identify the risk to the
environment from chloropicrin use as a soil fumigant in agricultural
crops. This initial analysis will be referred to as Tier I screening and
is based on the ratio or quotient method. As noted in the USEPA 1998,
Part A Section 5.1.3, "Typically, the ratio (or quotient) is expressed
as an exposure concentration divided by an effects concentration".
Therefore the risk quotient (RQ) is the ratio of the estimated
environmental concentration (EEC) of a chemical to a toxicity test
effect (e.g., LC~50~ ) for a given species. The RQ as an index of
potential adverse effects is then compared to an Agency established
Level of Concern (LOC) in order to identify when the potential adverse
effect is a concern to the Agency. These LOCs are the Agency's
interpretive policy and are used to analyze potential risk to non-target
organisms and the need to consider regulatory action. Appendix D of this
document summarizes the LOCs used in this risk assessment. This paper
presents a sequence of risk assessment methods that include PRZM/EXAMS
generated EEC values for aquatic exposure and ISCTS3 model simulated air
residue values for terrestrial wildlife exposure. The laboratory-derived
effects data for the most sensitive representative species of
terrestrial and aquatic organisms are included in Tables 9 and 10**.**
This screening-level assessment should identify habitats, and species
potentially at risk from chloropicrin exposure. The fate, effects, and
usage information presented in this document suggest that the focus of
the working hypothesis for an environmental risk assessment is that
exposure to chloropicrin has the potential to cause acute and chronic
effects that may result in reduced survival, reproductive impairment and
growth effects to aquatic and terrestrial animals and plant species.

**Data Gaps**

The adequacy of the submitted data was evaluated relative to Agency
guidelines. The following identified data gaps for ecological fate and
effects endpoints result in a degree of uncertainty in evaluating the
ecological risk of chloropicrin.

• No data are available to assess the acute or chronic risk of
chloropicrin to birds.

• No data are available to assess the chronic risk of chloropicrin to
freshwater or estuarine/marine fish.

• No data are available to assess the chronic risk of chloropicrin to
freshwater or estuarine/marine invertebrates.

• No data are available to assess the risk of chloropicrin to
terrestrial, aquatic, or semi-aquatic plants.

1.  The mammal acute inhalation study reviewed by HED has deficiencies
    and is considered non-guideline.

• Studies available on the effects of chloropicrin to freshwater fish
and aquatic invertebrates are considered supplemental, with
indeterminate toxicity values (i.e., "\<").

***2. Measures to Evaluate Risk Hypotheses and Conceptual Model***

a\. Measures of Exposure

Exposure concentrations for aquatic ecosystems were estimated based on
the Tier 2 aquatic model Pesticide Root Zone Model(PRZM; Carsel, et al.,
1998) and Exposure Analysis Modeling System (EXAMS; Burns, 2002). PRZM
(version 3.12 Beta compiled May 24, 2001) 2001) simulates the fate of
the chemical in the field, including runoff and erosion on a daily time
step, and EXAMS (version 2.98.04 compiled November 2002) simulates the
environmental fate and transport processes in a body of surface water. A
graphical user interface (pe4v01.pl), developed by the USEPA, 2004 was
used to facilitate the input of chemical, fate, and use specific
parameters into the appropriate PRZM and EXAMS files. PRZM/EXAMS model
simulates are run for multiple (usually 30) years and reported estimated
environmental concentration (EEC) are the concentrations that are
expected once in every ten years based on the thirty years of daily
values generated by the simulation. The critical measure of exposure for
a Tier 1 acute aquatic risk assessment is the peak EEC in surface water.
For chronic aquatic assessments, the 21-day average EEC is typically
used for aquatic invertebrates and the 60-day average is now typically
used for fish (both embryo-larvae and full lifecycle).

Exposure concentrations for terrestrial ecosystems were based on
estimated atmospheric concentrations of chloropicrin using the
Industrial Source Complex - Short Term (ISCST3) air dispersion model
developed by USEPA (USEPA, 1995). The modeling approaches used by the
Agency were based on 24 hours exposure intervals (i.e., 24 hours
time-weighted average of monitored air concentration of chloropicrin at
the edge of the fumigated field. Field sizes includes 1-, 5-, 10-, 20-,
and 40 acre squares to represent a cross section of the fields that
might be fumigated for agriculture use. ISCST3 model was used in
estimating air concentration using field emission ratio (ratio of the
flux rate to the application rate), various sized fields, methods of
chloropicrin placement, and different meteorological conditions. The
estimated maximum concentration of 0.019 mg/L (19037 μg/m^3^) was used
in calculating inhalation exposure for terrestrial organisms.

b\. Measures of Effect

Measures of effect are generally based on the results of a toxicity
study, although monitoring data and incident reports may also be used to
provide supporting lines of evidence for the risk characterization. A
complete summary of the potential measures of effect based on toxicity
studies for different ecological receptors and effect endpoints
(acute/chronic) is given in **Table 2** above. Examples of measures of
acute effects (e.g., lethality) include an oral LD~50~ for mammals and
LC~50~ for fish and invertebrates. Examples of measures of chronic
effects include a NOAEL for birds or mammals based on reproduction or
developmental endpoints, and an EC~05~ for plants based on growth rate
or biomass measurements.

c\. Measures of Ecosystem and Receptor Characteristics

For the Tier 1 assessment, the ecosystems that are modeled are intended
to be generally representative of any aquatic or terrestrial ecosystem
associated with areas where chloropicrin is used. The receptors
addressed by the aquatic and terrestrial risk assessments are summarized
in **Figure 1**. For aquatic assessments, generally fish, aquatic
invertebrates, and aquatic plants in both freshwater and
estuarine/marine environments are represented. For terrestrial
assessments, generally birds, terrestrial plants, and wild mammals are
included.

**III. Analysis**

**A. Use Characterization**

Chloropicrin is a broad-spectrum fumigant used for the control of weeds,
nematodes, insects, rodents, and certain fungi. Chloropicrin end-use
products are packaged as 100% chloropicrin formulations as well as in
combination formulations with methyl bromide and 1,3-D. In these
combination end-use products, the percent active ingredient for
chloropicrin can range from 20 to 55% when combined with methyl bromide
and from 15 to 60% when combined with 1,3-D.

Chloropicrin is registered for pre-plant soil fumigation of field to be
planted with a wide variety of food, ornamental, and nursery crops.
Typical use consists of making one application per year prior to
planting a crop or multiple crops in the fumigated field. Individually,
strawberries, tobacco, tomatoes, and peppers were the crops with the
highest percentage of their overall acreage treated from 1998 to 2000.
The average annual percent crop treated for those crops, respectively,
were 20, 15, 10, and 10 percent while the maximum percent crop treated,
respectively, for those crops was 50, 20, 45, and 30 percent. Crops that
use over a million pounds annually of chloropicrin in their production
include tobacco (3.6 million pounds), tomatoes (1.7 million pounds), and
strawberries (1.4 million pounds). Figure 2 shows the average pounds of
active ingredient was applied in various states for all surveys crops
based on three years (2002 to 2004) of EPA data (USEPA 2005a).

In general, two most frequent options of chloropicrin application
methods include shank injection (soil injection) followed by tarping and
drip irrigation (chemigation) under a pre-tarped soil surface.
Chloropicrin can also be applied using shank injection and drip
irrigation without tarping. Non-tarp shank injection application
requires lower rate (≤175 lbs/acre) of chloropicrin, possibly due to
requirements for worker protection. For drip irrigation, non-tarp
chloropicrin application in soil requires the placement of drip tubing
at a minimum depth of 5 inches from surface. Post application sealing
methods like tarping, water sealing, and compacting soil surface are
fumigant management practices followed immediately after fumigation to
contain the applied chloropicrin and reduce its diffusion into the
atmosphere.

The Chloropicrin Manufacturer's Task Force (CMTF) members have amended
the four existing manufacturing labels to use in delete use of
chloropicrin as an active ingredient in pesticide formulations for
post-harvest uses, structural fumigations, forestry uses, and aquatic
use patterns. The CMTF is supporting pre-plant soil fumigation use in
agricultural fields and commercial greenhouses. In addition to this
labeling change, CMTF is supporting the following maximum rates for
pre-plant soil fumigation use in agricultural field.

2.  350 lbs per treated acre for shank injection applications - tarped;

3.  175 lbs per treated acre for shank injection applications -
    untarped;

4.  300 lbs per treated acre for drip irrigation applications.

![](media/image5.emf){width="6.575694444444444in"
height="4.940277777777778in"}

**Figure 2. Average annual pounds of active ingredient of chloropicrin
was applied by state for all surveyed crops based on three years of EPA
data (2002-2004).**

There are some current chloropicrin labels that have higher maximum
application rates but CMTF has not conducted studies to support these
higher rates. At this time, the assessment reflects these new maximum
rates. Other registrants wishing to support higher rates must conduct
the appropriate studies and submit them to the Agency.

Chloropicrin is also used as an odorant when it is added to methyl
bromide (for pre-plant soil fumigation) and sulfuryl fluoride (indoor
fumigation) formulations at 2% by weight or less. When used in this
capacity, chloropicrin is not used as an active ingredient but as a
warning agent to indicate possible hazardous concentrations of odorless
methyl bromide or sulfuryl fluoride vapors.

> **B. Exposure Characterization**

***1. Environmental Fate and Transport Characterization***

Chloropicrin is a clear, colorless, nonflammable oily liquid with
strong, sharp, highly irritating odor and a strong lacrimator. Selected
physic-chemical and environmental fate properties of chloropicrin are
listed in Table 3 and 4. The high vapor pressure (23.8 mm @ 25^○^C),
high Henry's Law Constant (2.05 X 10^-3^ atm M^3^/mole), and low soil
adsorption coefficient (K~oc~ 36.05 L kg^-1^) on soil of chloropicrin
suggest that volatilization is the most important environmental route of
dissipation. Direct photolytic degradation (t~1/2~ \<8 hrs) of
chloropicrin is the primary route of dissipation in the atmosphere,
which suggest it is not a significant threat to deplete stratosphere
ozone layer. Due to the fact that volatilization is significant and
occurs rapidly, the importance of other competing processes such as
leaching, biotic and abiotic degradation, and adsorption to the soil
particles will certainly depend on chloropicrin emission rate from
fumigated fields. This is because emission rate determines the amount of
chloropicrin left for other processes and its residence time in the soil
system. However, if chloropicrin remains in soil, it also degrades in
soil with half-lives ranges from 4.5 to 10 days with CO~2~ being the
terminal breakdown product. Since chloropicrin is highly soluble in
water and has low adsorption in soil, it can potentially leach into
groundwater and to surface water through runoff under a flooded
condition. The low octanol/water partition coefficient of chloropicrin
also indicates that it is not likely to be bioconcentrated in tissues of
aquatic organisms.

  ------------------------------------------------------------------------
  **Table 3: Selected                            
  physical and chemical                          
  properties of                                  
  chloropicrin**                                 
  --------------------- ------------------------ -------------------------
  **Parameter**         **Value**                **Reference**

  Chemical Structure    ![](media/image6.emf)    

  PC Code               081501                   

  CAS number            76-06-2                  

  Common name           Chloropicrin             

  SMILES Notation       N(=O)(=O)C(CL)(CL)CL     

  Molecular formula     CCl~3~NO~2~              MRID# 43613901

  Molecular weight      164.38 g/mol             MRID# 43613901

  IUPAC name            trichloronitromethane    Merck Index

  CAS name              trichloronitromethane    Merck Index

  Physical State        Near colorless, oily     Merck Index
                        liquid                   

  Melting point/range   -69.2̊C                   Merck Index

  Boiling point/range   112̊C at 757 mm Hg        Merck Index

  Density               1.7 g/mL at 25 ̊C         Merck Index

  Water solubility      1.612 g/L @ 25^○^C       MRID# 43613901

  Vapor pressure        23.8 mm Hg at 25 ̊C       Merck Index

  Henry's Law Constant@ 2.05 \* 10^-3^           Kawamoto and Urano, 1989
  25^o^C                atm•m^3^/mole            

  Octanol/water         2.38                     Kawamoto and Urano, 1989
  partition coefficient                          
  (Log K~OW~)                                    
  ------------------------------------------------------------------------

+---------------------+------------------------+-----------------------+
| **Table 4.          |                        |                       |
| Environmental Fate  |                        |                       |
| Properties of       |                        |                       |
| Chloropicrin**      |                        |                       |
+=====================+========================+=======================+
| **Parameter**       | **Value**              | *                     |
|                     |                        | *Reference/Comments** |
+---------------------+------------------------+-----------------------+
| ***Persistence***   |                        |                       |
+---------------------+------------------------+-----------------------+
| Hydrolysis t~1/2~   | Stable at pH 5, 7, and | MRID# 43022401        |
|                     | 9                      |                       |
+---------------------+------------------------+-----------------------+
| Photolysis t~1/2~   | 1.3 days, degradates   | MRID# 42900201        |
| in water            | chloride, nitrate,     |                       |
|                     | nitrite, and CO~2~     |                       |
+---------------------+------------------------+-----------------------+
| Photolysis t~1/2~   | N/A                    | Waived                |
| on soil             |                        |                       |
+---------------------+------------------------+-----------------------+
| Photolysis t~1/2~   | ≤8.0 Hours             | Carter et al., 1997   |
| in air              |                        |                       |
|                     | 20 days                | MRID# 05007865        |
|                     |                        |                       |
|                     | phosgene (COCl~2~),    |                       |
|                     | nitrosyl chloride      |                       |
|                     | (NOCl), nitrous oxide  |                       |
|                     | (NO), and chlorine     |                       |
|                     | (Cl~2~); subsequently  |                       |
|                     | nitrogen dioxide       |                       |
|                     | (NO~2~) and dinitrogen |                       |
|                     | tetraoxide (N~2~O~4~)  |                       |
+---------------------+------------------------+-----------------------+
| Soil metabolism     | 4.5 days               | Wilhelm et al., 1996  |
| Aerobic t~1/2~      |                        |                       |
|                     | 10 days                | MRID# 43613901        |
|                     |                        |                       |
|                     | major degradate is     |                       |
|                     | CO~2~                  |                       |
|                     |                        |                       |
|                     | minor degradates       |                       |
|                     | (total \<6%)           |                       |
|                     | chloronitromethane,    |                       |
|                     | nitromethane, and      |                       |
|                     | bicarbonate            |                       |
+---------------------+------------------------+-----------------------+
| Aquatic metabolism  | 1.3 hours              | MRID# 43759301        |
| Anaerobic t~1/2~    |                        |                       |
|                     | major degradates       |                       |
|                     | nitromethane and       |                       |
|                     | chloronitromethane     |                       |
+---------------------+------------------------+-----------------------+
| Aquatic metabolism  | N/A                    | Waived                |
| Aerobic t~1/2~      |                        |                       |
+---------------------+------------------------+-----------------------+
| ***Mobility/Adsor   |                        |                       |
| ption-Desorption*** |                        |                       |
+---------------------+------------------------+-----------------------+
| K~OC~               | 36.05 L kg^-1^         | EPISUITE              |
+---------------------+------------------------+-----------------------+
| Laboratory          | Non-tarped soil        | MRID# 43798601        |
| Volatility          | maximum volatility 342 |                       |
|                     | μg/cm^2^/hr;           |                       |
|                     |                        |                       |
|                     | Tarped soil maximum    |                       |
|                     | volatility             |                       |
|                     |                        |                       |
|                     | 205 μg/cm^2^/hr        |                       |
+---------------------+------------------------+-----------------------+
| ***Field            |                        |                       |
| Dissipation***      |                        |                       |
+---------------------+------------------------+-----------------------+
| Terrestrial Field   | ≤1.4 days from 3- to   | MRID# 43085101        |
| Dissipation         | 12-inch depth from a   |                       |
|                     | sandy loam and a sand  |                       |
|                     | from California,       |                       |
|                     | measured after tarp    |                       |
|                     | was removed            |                       |
+---------------------+------------------------+-----------------------+
| Aquatic Field       | N/A                    | Waived                |
| Dissipation         |                        |                       |
+---------------------+------------------------+-----------------------+
| **                  |                        |                       |
| *Bioaccumulation*** |                        |                       |
+---------------------+------------------------+-----------------------+
| Accumulation in     | N/A                    | Waived                |
| Fish, max. BCF      |                        |                       |
+---------------------+------------------------+-----------------------+

> ***(a) Fate and Transport in soil and water***

The dissipation of chloropicrin in aquatic and terrestrial environments
appears to be predominantly dependent on volatilization and to a lesser
extent on leaching and degradation. The high vapor pressure and the high
Henry's Law Constant suggests that chloropicrin will volatilize from
soil and water. Once it volatilized, chloropicrin degrades rapidly into
CO~2~ and other metabolites in the atmosphere via direct photolysis. The
importance of other competing processes such as leaching,
biodegradation, and adsorption to the soil particles will certainly
depend on chloropicrin emission rate from the fumigated fields. This is
because emission rate determines the amount of chloropicrin left for
other processes and its residence time in the soil system. The
biodegradation half-lives of chloropicrin is 10 days with carbon dioxide
being the terminal breakdown product (MRID 43613901). Also, a cursory
review of literature data (Wilhelm et al., 1996, Gan et al., 2000) shows
that major metabolic pathways occurs through successive reductive
dehalogenation of chloropicrin to nitromethane:

**CCl~3~NO~2~ → HCCl~2~NO~2~ → H~2~CClNO~2~ → H~3~CNO~2~ → CO~2~**

Degradation of chloropicrin in soil follows first-order kinetics.
Wilhelm et al.(1996) estimated the half-life of 4.5 days for
chloropicrin in sandy loam soil with a rate equivalent to 500 lbs/Acre
following the Agency's Pesticide Assessment Guidelines. Gan et al.
(2000) estimated that microbial degradation accounted for 68 to 92
percent of the overall degradation of applied chloropicrin.

Chloropicrin is highly soluble in water and are weakly retained by soil.
The supplemental terrestrial field dissipation studies (MRID 43085101)
were conducted in California, applying chloropicrin to bare fallow soils
at a rates of 665 lbs and 792 lbs a.i/acre through chisel injection
followed by tarping for 48 hours. The calculated field dissipation
half-lives was less than 33.4hours. Volatilization of chloropicrin from
applied fields may have resulted in short half-lives in the field
dissipation study. Concentrations of chloropicrin at the 24-, 36-, and
48-inch depths increased to a maxima of 593.0, 230.5, and 75.2 ppm,
respectively; times of maximum concentration were 12, 24, and 48 hours,
respectively, after removal of the tarp.

The high Henry's Law Constant (2.05 X 10^-3^ atm M^3^/mole) and rapid
photohydrolysis of chloropicrin suggest that volatilization and rapid
degradation are the primary environmental routes of dissipation from
surface water. The calculated half-life of 31.1 hours for in aqueous
solution (pH 7) when irradiated with xenon light source forming carbon
dioxide, chloride, nitrate and nitrite (MRID 42900201). In the absence
of light, chloropicrin did not hydrolyzed in sterile aqueous buffered
solution under acidic to alkaline pH (MRID 43022401).

Soil adsorption coefficient (K~oc~) of chloropicrin cannot be estimated
from the batch equilibrium study. Due to the rapid volatilization of
chloropicrin, it is unlikely that an equilibrium of chloropicrin in the
batch equilibrium will be reached. The K~oc~ of chloropicrin was
estimated using the EPA's computer model PCKOCWIN v1.66 of EPISUITE.
EPI\'s K~oc~ estimations are based on the Sabljic molecular connectivity
method. The estimated K~oc~ of chloropicrin is 36.05 ml/g.
Chloropicrin's high water solubility (1621 mg/L) and low K~oc~ of 36.05
ml/g suggest its high mobility in the environment. The high solubility
and low soil absorption of chloropicrin can result in movement of it
downward to groundwater with water infiltration under an intense
rainfall or continuous irrigation right after chloropicrin application.
A supplemental leaching study (MRID 44191301) demonstrated that
chloropicrin was very mobile in all four soils.

***(b) Fate and Transport in atmosphere***

In a review of the environmental fate of chloropicrin, Kollman 1990,
noted that chloropicrin was likely to have relatively short persistence
in the atmosphere. Chloropicrin was found to be susceptible to direct
photolytic degradation in air. Laboratory simulation of exposure to
artificial sunlight found that it degraded with a half-life of 20 days
(MRID 05007865, Moilanen et al. 1978). However, a later study using a
light source that better simulated the spectral intensity of sunlight
found chloropicrin to photolyze much more rapidly, with an estimated
atmospheric half-life of 3.4 to 8 hours in direct sunlight (Carter et
al., 1997), leading to an estimate of 1 day for its atmospheric
lifetime. The major degradation products were phosgene (carbonyl
chloride) and nitrosyl chloride, which rapidly photolyzes to reactive
products NO and Cl• (Carter et al., 1997). Continued oxidation of the
chloropicrin photolysis products would eventually produce CO~2~, NO~2~,
N~2~O~4~, and Cl~2~ (Ecotoxnet 2001). Phosgene has been detected in air
downwind from a field application of chloropicrin (Woodrow et al. 1983),
consistent with the results of laboratory photodegradation studies.

Although chloropicrin has significant aqueous solubility, its high vapor
pressure results in limited partitioning into water; thus its Henry's
Law Constant, 2.05 x 10^-3^ atm m^3^/mol is comparable to that of long
lived atmospheric vapors such as elemental mercury. Washout by rainfall
would occur, but not at a rate likely to cause a significant reduction
in the atmospheric half life of chloropicrin estimated from direct
photodegradation. Similarly, uptake and subsequent degradation in soils
and oceans would occur, but rates of these processes would likely be
limited by atmospheric delivery to the soil or water interface, and
hence approximate rates estimated for methyl bromide (Shorter et al.
1995, Yvon and Butler 1996).

An overall atmospheric lifetime for chloropicrin can be computed using
the procedure followed by USEPA 2005b, in which an overall ‛total
lifetime' is computed from estimates of lifetimes computed from
photodegradation, oceanic uptake and terrestrial uptake:

1/τ~total~ = 1/τ~p~ + 1/τ~o~ + 1/τ~s~ (1)

where τ~p~, is the atmospheric lifetime associated with processes of
direct and indirect photo and

chemical degradation and precipitation scavenging; and τ~o~ ,and τ~s~
are lifetimes associated with uptake by oceanic and terrestrial
surfaces, respectively.

The atmospheric lifetime of chloropicrin in the atmosphere was estimated
to be 1 day (0.0027 years), based on the published photodegradation rate
(Carter et al., 1997). If atmospheric lifetimes of 2.7 and 3.4 years are
assumed for oceanic and terrestrial uptake and degradation processes
(from methyl bromide), the estimate of atmospheric lifetime for
chloropicrin remains 0.0027 years.

The highly toxic gas phosgene (once used as a chemical warfare agent) is
a major photodegradation product of chloropicrin. Phosgene is resistant
to both direct and indirect photochemical degradation processes in the
atmosphere (Grosjean 1991; Helas and Wilson 1992), but it is extremely
reactive with water, hydrolyzing rapidly to carbon dioxide and
hydrochloric acid (Manoque and Pigford 1960). The dominant process
removing phosgene from the atmosphere is its reaction with liquid water
droplets (fog, clouds, and rain), with a tropospheric lifetime estimated
at 10 hours to 1 day (Manoque and Pigford 1960). Despite its short
atmospheric half life, phosgene has been commonly detected in air,
especially in urban/industrial areas, with typical concentrations of 80
to 130 ng/m3 (WHO 1998). Phosgene is a widely used precursor in the
chemical industry, with 3 x 10^6^ metric tons produced and used annually
(WHO 1998). Phosgene is also formed in the atmosphere by the
photochemical oxidation of chloroethylenes, with generation rates
estimated to be 350,000 metric tons annually (Singh 1976). Phosgene
generation by conversion of 100% of chloropicrin used agriculturally in
the U.S. would amount to about 6000 metric tons annually (based on U.S
usage of 9000 metric tons/year (NASS 2005). Even with such unrealistic
conversion assumptions, chloropicrin usage appear to be a minor source
of atmospheric phosgene relative to other sources.

Nitrosyl chloride is also produced in the photolysis of chloropicrin.
This highly toxic gas is both photoreactive and readily hydrolyzed, and
is estimated to have an atmospheric lifetime of less than 1 hour (Scheer
et al. 1997).

The reactive byproducts of chloropicrin photolysis, in particular
chlorine free radicals and NO~x~, could lead to the generation of
tropospheric ozone, although its potential (on a per molecule basis) for
contributing to the generation of ozone in polluted urban atmospheres is
no greater than the typical organic air pollutants contributing to the
problem (Carter et al., 1997).

***(c) Ozone Depletion Potential***

The United Nations Industrial Development Organization listed
chloropicrin as a non-ozone depleting alternative fumigant (UNIDO 2003).
The ozone depletion potential (ODP) of methyl bromide was calculated by
USEPA (USEPA, 2005) as 0.38 using an approach published in WMO 2002. In
that approach, ODP is estimated by:

ODP(x) =FRF\*α\*τ~x~/τ~CFC-11~\*M~CFC-11~/M~x~\*n~x~/3 (2)

where FRF is the fractional release factor that describes the
availability of a halogen for release from substance x relative to
CFC-11, alpha is the efficacy of a halogen relative to chlorine at ozone
destruction, and τ is the atmospheric lifetime or turnover time, M is
molecular weight, and n~x~ is the number of halogen in a molecule of x.
Using the FRF for methyl bromide (Agency was unable to find a value for
chloropicrin), the ODP for chloropicrin is calculated as:

ODP~(chloropicrin)~ = \[1.12\*1\*(0.0027/45)\*137.7\]/\[164.4\*(3/3)\]
(3)

=5.6\*10^-5^

With an ozone depletion potential more than four orders of magnitude (
5.6\*10^-5^ versus 0.38) less than methyl bromide, stratospheric ozone
depletion will not be a concern with the use of chloropicrin as a
fumigant.

**2. Measures of Terrestrial Exposure**

***(a)Terrestrial Exposure Modeling***

To determine terrestrial exposure of chloropicrin, a deterministic
approach was used in estimating exposures around the treated fields.
This deterministic approach is based on monitoring data of chloropicrin
and the use of the EPA's Industrial Source Complex: Short-Term Model
(ISCST3) air dispersion model developed by USEPA (U.S.EPA, 1995). ISCST3
is a steady-state Gaussian plume model, which can be used to assess
pollutant concentrations from a wide variety of sources. The ISCST3
model is a publically vetted tool that is currently used by the Agency's
Office of Air for regulatory decision making. A number of support
documents for this tool can be found at the Agency's website *Technology
Transfer Network Support Center for Regulatory Air Models*
([[http://www.epa.gov/scram001/tt22.htm#isc.]{.underline}](../(http://www.epa.gov/scram001/tt22.htm#isc.))
The ISCST3 has been used successfully to simulate fumigant levels in air
following the fumigation of warehouses and agricultural fields located
in California (Barry et al. 1997). ISCST3 provides useful results
because it allows estimation of air concentrations based on changing
factors such as application rates, field sizes, downwind distances, wind
and weather conditions, and other factors. Using this model for the soil
fumigants allows EPA to predict off-site movement given fixed
meteorological and other conditions.

The modeling approaches used by the Agency were based on 24 hours
exposure intervals (i.e., 24 hours time-weighted average of monitored
air concentration of chloropicrin). Field sizes includes 1-, 5-, 10-,
20-, and 40 acre squares to represent a cross section of the fields that
might be fumigated for agriculture use. ISCST3 was used in estimating
air concentration using field emission ratio (ratio of the flux rate to
the application rate), various sized fields, methods of chloropicrin
placement, and different meteorological conditions. The basic approaches
to estimate air concentrations using ISCST3 model are outlined in the
Health Effects Division's Draft Standard Operating Procedures (SOPs) for
Estimating Bystander Risk from Inhalation Exposure to Soil Fumigant
(USEPA,2004)*.* ISCST3 estimated downwind air concentrations using
hourly meteorological conditions that include the wind speed and
atmospheric stability.

In this assessment, one set of computations was completed using ISCST3
model at varying acreage and atmospheric conditions. The lower the wind
speed and more stable the atmospheric environment, the higher the air
concentrations were observed near the treated areas. The outputs were
then scaled to appropriate emission ratios and application rates
assuming stable weather condition, Table 5 reflects a wide variety of
application rates and methods as well as the estimated concentrations of
chloropicrin in air at the edge of a 40 acres field size under stable
weather condition. The estimated maximum concentration of 0.019 mg/L
(19037 μg/m^3^) was used in calculating inhalation exposure for
terrestrial organisms. California fumigant Permit conditions and
detailed input assumptions and model results were described in the HED's
Draft Chapter on Non-Occupational Risks Associated with Chloropicrin
(USEPA, 2005c).

The specific inputs for the ISCST3 model calculations drove the
associated uncertainties in the results. For example, the key input
factors for pre-plant agricultural uses were field size, flux/emission
rates, atmospheric stability, and windspeed. Wind direction is another
factor which also should be considered. The field sizes used by the
Agency in this assessment were 1 to 40 acres which is well within the
range of what could be treated on a daily basis. There are uncertainties
associated with point estimates of flux/emission rates for specific
application techniques which is another varying factor. The flux rates
which were used have been calculated by the Agency and they compare
reasonably well with those calculated by the study investigators. The
reality is that there is a large distribution of flux rates which is a
phenomena inherent in the nature of these types of data.

+---------------------+-------+---------+------+------+------+------+
| **Table 5. ISCTS3   |       |         |      |      |      |      |
| estimated air       |       |         |      |      |      |      |
| concentrations of   |       |         |      |      |      |      |
| chloropicrin at     |       |         |      |      |      |      |
| various distances   |       |         |      |      |      |      |
| from the edge of 40 |       |         |      |      |      |      |
| acres fumigated     |       |         |      |      |      |      |
| fields (meter)      |       |         |      |      |      |      |
| under several       |       |         |      |      |      |      |
| application         |       |         |      |      |      |      |
| methods**           |       |         |      |      |      |      |
+=====================+=======+=========+======+======+======+======+
| **Application       | *     | **Appl  | **   |      |      |      |
| Methods**           | *Tarp | ication | Conc |      |      |      |
|                     | ing** | Rate**  | entr |      |      |      |
|                     |       |         | aton |      |      |      |
|                     |       | **(lbs/ | Chlo |      |      |      |
|                     |       | Acre)** | ropi |      |      |      |
|                     |       |         | crin |      |      |      |
|                     |       |         | in   |      |      |      |
|                     |       |         | Air  |      |      |      |
|                     |       |         | (μg  |      |      |      |
|                     |       |         | /m^3 |      |      |      |
|                     |       |         | ^)** |      |      |      |
+---------------------+-------+---------+------+------+------+------+
|                     |       |         | **0  | **25 | **50 | *    |
|                     |       |         | M    | M**  | M**  | *100 |
|                     |       |         | \*** |      |      | M**  |
+---------------------+-------+---------+------+------+------+------+
| Shank Injection     | Yes   | 350     | 1    | 1    | 8915 | 6876 |
| Broadcast           |       |         | 9037 | 0951 |      |      |
+---------------------+-------+---------+------+------+------+------+
| Shank Injection     | No    | 175     | 1    | 9126 | 7429 | 5730 |
| Broadcast           |       |         | 5864 |      |      |      |
+---------------------+-------+---------+------+------+------+------+
| Shank Injection     | Yes   | 350     | 1    | 6511 | 5301 | 4088 |
| Raised Bed          |       |         | 1319 |      |      |      |
+---------------------+-------+---------+------+------+------+------+
| Shank Injection     | No    | 175     | 1    | 6610 | 5381 | 4150 |
| Raised Bed          |       |         | 1491 |      |      |      |
+---------------------+-------+---------+------+------+------+------+
| Drip Irrigation     | Yes   | 300     | 4373 | 2515 | 2048 | 1580 |
+---------------------+-------+---------+------+------+------+------+
| \* Distances        |       |         |      |      |      |      |
| (meter) from the    |       |         |      |      |      |      |
| edge of the field   |       |         |      |      |      |      |
+---------------------+-------+---------+------+------+------+------+

The values used for this assessment yield conservative air concentration
estimates because considering a constant flux rate does not allow for
diurnal/nocturnal changes that may occur, which when coupled with the
appropriate wind speed and stability category, can result in lower
concentrations. The meteorological inputs also will provide a
conservative estimate of exposure because the wind direction is
considered to be perpendicular (pointed downwind) to the treated field
for the entire 24 hours represented in the calculation. This is not a
normal situation in the atmosphere for most locations. There is normally
a prevailing wind with directional changes over the course of a typical
day, especially when diurnal and nocturnal differences are noted.
Overall, Agency believes that the approach used to evaluate potential
exposures from a known area source can be considered conservative. It is
believed, however, that the range of selected input values and outputs
represent what could reasonably occur in agriculture given proper field
and climatological conditions.

***(b) Terrestrial Exposure Monitoring Data***

The short atmospheric lifetime indicate that readily detectable
concentrations of chloropicrin should not accumulate in the atmosphere.
A rough estimate of the steady-state tropospheric concentration that
would be attained for release of 9000 metric tons/year (US annual usage
in 2002, (NASS 2005)) to the atmosphere can be calculated by:

Input = Removal

= (1/τ~chloropicrin~)\*volume of troposphere\*steady state
\[chloropicrin\]~air~ (4)

rearranged to:Steady State \[chloropicrin\]~air~ = Input(moles/y)/
(volume of troposphere(1.6 x 10^20^ moles)\*1/τ~chloropicrin~) and
yielding:

Steady State \[chloropicrin\]~air~ = 5.5X10^7^ moles/y/( 1.6x10^20^
moles\*1/0.0027 y)

= 9.28 x 10^-16^ mole fraction

= 9.28 x 10^-4^ ppt

=6.24 x 10^-3^ ng/m^3^

If much of chloropicrin added to soils is degraded within the soil and
not volatilized, an even lower steady state concentration would be
expected.

Background concentrations (concentrations in air at sites remote from
areas of recent application) of chloropicrin in air were below the
analytical detection limit (30 ng/m^3^) based on upwind or off target
monitoring by the California Air Resources Board (CARB 2004, 2003).
Thus, as predicted by its short atmospheric half life, the detection and
measurement of chloropicrin in air is largely a local phenomenon.
Measured concentrations would be expected to vary greatly with time and
distance from areas of application, and with size and application rates
of the areas receiving treatment.

In monitoring conducted in urban and rural communities near agricultural
sites where chloropicrin was being applied in Monterey and Santa Cruz
Counties, the California Air Resources Board observed concentrations of
chloropicrin to range from undetected (\<30 ng/m^3^) to 14000 ng/m^3^,
with a range of 8-week average concentrations of 406 to 2270 ng/m^3^.
Chloropicrin was undetected in only 7 of 192 samples (CARB 2004).
Similar monitoring in Kern County found much lower levels of
chloropicrin (\<30 - 750 ng/m^3^, 8-week averages ranging from \<30 - 42
ng/m^3^), but chloropicrin was not being used extensively during the
season at that location (CARB 2004). Most of the samples collected (185
of 198) were below the detection limit (\<30 ng/m3). An assessment of
chloropicrin risks to residents in rural communities estimated a mean 24
hour concentration of 210 ng/m^3^ for residents during periods of
chloropicrin application to nearby agricultural areas (Lee et al. 2002).
Ambient chloropicrin concentrations are presented in **Table 6**.

+-----------------+-----------------+----------+-------+--------------+
| **Table 6.      |                 |          |       |              |
| Ambient air     |                 |          |       |              |
| concentrations  |                 |          |       |              |
| of chloropicrin |                 |          |       |              |
| near fumigated  |                 |          |       |              |
| fields.**       |                 |          |       |              |
+=================+=================+==========+=======+==============+
| **              | **Exposure      | **Lo     | **D   | *            |
| Concentration** | Type**          | cation** | ate** | *Reference** |
|                 |                 |          |       |              |
| **(ng/m^3^)**   |                 |          |       |              |
+-----------------+-----------------+----------+-------+--------------+
| 210 ± 590       | Rural           | Kern     | 1996  | Lee et al.   |
|                 | residential     | Co., CA  |       | 2002         |
| \<85 - 4600     |                 |          |       |              |
+-----------------+-----------------+----------+-------+--------------+
| \<85            | Urban           | Kern     | 1996  | Lee et al.   |
|                 | residential     | Co., CA  |       | 2002         |
+-----------------+-----------------+----------+-------+--------------+
| \<30 -14,000    | Rural           | M        | 2001  | CARB 2004    |
| daily,          | residential     | onterey, |       |              |
|                 |                 | Santa    |       |              |
| 8 week average  |                 | Cruz     |       |              |
| =               |                 | Co., CA  |       |              |
|                 |                 |          |       |              |
| 406 - 2270      |                 |          |       |              |
+-----------------+-----------------+----------+-------+--------------+
| \<30 - 3,300    | Urban           | M        | 2001  | CARB 2004    |
| daily,          | residential     | onterey, |       |              |
|                 |                 | Santa    |       |              |
| 8 week average  |                 | Cruz     |       |              |
| = 660           |                 | Co., CA  |       |              |
+-----------------+-----------------+----------+-------+--------------+
| \<30 - 750, 8   | Rural           | Kern     | 2001  | CARB 2003    |
| week average =  | residential     | Co., CA  |       |              |
| \<40            |                 |          |       |              |
+-----------------+-----------------+----------+-------+--------------+

**3. Measures of Aquatic Exposure**

> ***a. Aquatic Exposure Modeling***

Henry's Law constant (2.05^-3^ atm-m^3^/mol) of chloropicrin suggest
that rapid volatilization of chloropicrin from water and soil surfaces
is expected to be an important process. Since Tier I model GENEEC is not
capable in accounting the loss of the vapor phase of chloropicrin from
the fumigated field, Tier II PRZM/EXAMS was used in estimating
chloropicrin concentrations in surface water. Additional chemical
specific physical parameters vapor phase diffusion coefficient (DAIR)
and enthalpy of vaporization (ENPY) were activated during the PRZM/EXAMS
simulation. Intended application methods via shank or drip irrigation
are to fumigate subsurface uniformly. Therefore, chemical application
method (CAM) of 8 was used in mimicking subsurface fumigation of
chloropicrin to simulate its uniform distribution within 25 cm through
vapor diffusion under the tarp. Six field scenarios - California
tomatoes, California onion, Florida strawberries, Florida tomato, North
Carolina tobacco and North Carolina sweet potato were used in estimating
EECs using highest application rate of 350 lbs/Acre. Chloropicrin uses
in major crops like tomato, strawberries and tobacco as well as minor
crops like onion and sweet potato scenarios were used in simulating
PRZM/EXAMS to capture aquatic exposure under diverse crop scenarios.

Estimated environmental concentrations (EEC) of chloropicrin in surface
waters were calculated using PRZM v.3.12 (Pesticide Root Zone Model),
which simulates runoff and erosion from the agricultural field, and
EXAMS v.2.98 (Exposure Analysis Modeling System), which simulates
environmental fate and transport in surface water. A graphical user
interface developed by EPA
([[http://www.epa.gov/oppefed1/models/water/]{.underline}](http://www.epa.gov/oppefed1/models/water/)
) was employed to enter the input values for each model run. A
Mississippi pond scenario was used to determine estimated environmental
concentrations (EEC) for ecological risk assessment. Each described a
generic scenario for the EXAMS portion of the modeling exercise.
Important input parameters used for the PRZM/EXAMS modeling are shown in
Table 7.

+------------------------------+-----------------+---------------------+
| **Table 7. PRZM/EXAM Input   |                 |                     |
| Parameters for               |                 |                     |
| Chloropicrin**               |                 |                     |
+==============================+=================+=====================+
| **Parameters**               | **Values &      | **Sources**         |
|                              | Units**         |                     |
+------------------------------+-----------------+---------------------+
| Molecular Weight             | 164.39 g        | MRID 43613901       |
|                              | Mole^-1^        |                     |
+------------------------------+-----------------+---------------------+
| Vapor Pressure 25^o^C        | 23.8 mm Hg      | Merck Index         |
+------------------------------+-----------------+---------------------+
| Water Solubility @ pH 7.0    | 1621 mg L^-1^   | MRID 43613901       |
| and 25^o^C                   |                 |                     |
+------------------------------+-----------------+---------------------+
| DAIR                         | 4858.6          | Fuller et al., 1966 |
|                              | cm^2^/day       |                     |
+------------------------------+-----------------+---------------------+
| ENPY                         | 9.39 kcal/mole  | Chickos and Acree,  |
|                              |                 | 2003                |
|                              | (39.3 kj/mol)   |                     |
+------------------------------+-----------------+---------------------+
| Henry's Law Constant @       | 2.05 X 10^-3^   | Kawamoto and Urano, |
| 25^o^C                       | atm M^3^/mole   | 1989                |
+------------------------------+-----------------+---------------------+
| Hydrolysis Half-Life (pH 7)  | Stable          | MRID 43022401       |
+------------------------------+-----------------+---------------------+
| Aerobic Soil Metabolism      | 15.71 days      | Calculated 90^th^   |
| t~½~,                        |                 | Percentile          |
|                              |                 |                     |
|                              |                 | MRID#s 43613901     |
|                              |                 |                     |
|                              |                 | Wilhelm et al.,     |
|                              |                 | 1996                |
+------------------------------+-----------------+---------------------+
| Aerobic Aquatic metabolism:  | 31.42 Days\*\*  | EFED Guideline      |
+------------------------------+-----------------+---------------------+
| Anaerobic Aquatic            | 0.05 Days       | MRID 43759301       |
| metabolism: for entire       |                 |                     |
| sediment/water system        |                 |                     |
+------------------------------+-----------------+---------------------+
| Aqueous Photolysis           | 1.3 Day         | MRID#s 42900201     |
+------------------------------+-----------------+---------------------+
| Soil Water Partition         | 36.05 L Kg^-1^  | EPISUITE            |
| Coefficient                  |                 |                     |
+------------------------------+-----------------+---------------------+
| Pesticide is Wetted-In       | No              | Product Label       |
+------------------------------+-----------------+---------------------+
| **Crop Management**          |                 |                     |
+------------------------------+-----------------+---------------------+
| Application rates (lb        | 350 and 1X      | Shank               |
| a.i./A) and Frequency        |                 | injection\*\*\*     |
+------------------------------+-----------------+---------------------+
| Fumigation Date for Florida  | September 15    | USDA                |
| and California               |                 |                     |
|                              | April 15        |                     |
| Fumigation Date for North    |                 |                     |
| Carolina                     |                 |                     |
+------------------------------+-----------------+---------------------+
| Application Method           | Ground          | Standard assumption |
|                              | Application     |                     |
|                              |                 |                     |
|                              | (CAM 8)\*\*\*   |                     |
+------------------------------+-----------------+---------------------+
| Application Efficiency       | 100%            | Standard assumption |
+------------------------------+-----------------+---------------------+
| \* In absence of aerobic     |                 |                     |
| aquatic metabolism           |                 |                     |
| half-life, the reported      |                 |                     |
| half-lives of aerobic soil   |                 |                     |
| metabolism multiplied by 2   |                 |                     |
| according to Guidance for    |                 |                     |
| selecting input parameters   |                 |                     |
| in modeling for              |                 |                     |
| environmental fate and       |                 |                     |
| transport of pesticides.     |                 |                     |
| Version II. December 4,      |                 |                     |
| 2001.                        |                 |                     |
|                              |                 |                     |
| \*\* The EPI (Estimation     |                 |                     |
| Program Interface) Suite is  |                 |                     |
| a Windows® based suite of    |                 |                     |
| physical/chemical property   |                 |                     |
| and environmental fate       |                 |                     |
| estimation models developed  |                 |                     |
| by the EPA's Office of       |                 |                     |
| Pollution Prevention Toxics  |                 |                     |
| and Syracuse Research        |                 |                     |
| Corporation SRC.             |                 |                     |
| http://www.e                 |                 |                     |
| pa.gov/opptintr/exposure/doc |                 |                     |
| s/updates_episuite_v3.11.htm |                 |                     |
|                              |                 |                     |
| \*\*\* = Chemical            |                 |                     |
| Application method 8 using   |                 |                     |
| shank Injection to assume    |                 |                     |
| uniform distribution of      |                 |                     |
| chloropicrin within upper 25 |                 |                     |
| cm soil depth                |                 |                     |
+------------------------------+-----------------+---------------------+

There are is an uncertainty in estimating chloropicrin exposure in water
bodies due to post-application tarping of the treated area. If tarping
is used to minimize the volatilization of chloropicrin, the loading of
the chemical through runoff will be limited until the tarp is sliced or
removed from the field. The present version of PRZM model and selected
crop scenarios have limited capabilities in capturing the load of
applied chemical under a post-application tarp scenario. PRZM also has
limited capabilities in capturing the partitions of volatile chemical in
air, water and sediment. Therefore, the estimated concentrations of
chloropicrin in water bodies may be upper bound since the load of
chloropicrin from runoff is considered in the PRZM/EXAMS simulation.

+------------+-----------------+-----------+-------------+-------------+
| **Table 8: |                 |           |             |             |
| Estimated  |                 |           |             |             |
| Env        |                 |           |             |             |
| ironmental |                 |           |             |             |
| Concen     |                 |           |             |             |
| trations\* |                 |           |             |             |
| (EECs) of  |                 |           |             |             |
| Ch         |                 |           |             |             |
| loropicrin |                 |           |             |             |
| in surface |                 |           |             |             |
| water for  |                 |           |             |             |
| selected   |                 |           |             |             |
| crop       |                 |           |             |             |
| s          |                 |           |             |             |
| cenarios** |                 |           |             |             |
+------------+-----------------+-----------+-------------+-------------+
| **Crops**  | **Application   | **Acute:  | **Chronic** | **Chronic** |
|            | rate            | Peak**    |             |             |
|            | frequency**     |           | **21-day    | **60-day    |
|            |                 | **EEC**   | Avg. EEC**  | Avg. EEC**  |
|            |                 |           |             |             |
|            |                 | **μg/L**  | **μg/L**    | **μg/L)**   |
+------------+-----------------+-----------+-------------+-------------+
| California | 350 lbs         | 3.66      | 1.42        | 0.61        |
| Tomato     | a.i./Acre       |           |             |             |
|            |                 |           |             |             |
|            | 1X Per Season   |           |             |             |
+------------+-----------------+-----------+-------------+-------------+
| California | 350 lbs a.i./A  | 2.14      | 0.61        | 0.24        |
|            |                 |           |             |             |
| Onion      | 1X Per Season   |           |             |             |
+------------+-----------------+-----------+-------------+-------------+
| Florida    | 350 lbs         | 107.8     | 30.7        | 12.48       |
|            | a.i./Acre       |           |             |             |
| Tomato     |                 |           |             |             |
|            | 1X Per Season   |           |             |             |
+------------+-----------------+-----------+-------------+-------------+
| Florida    | 350 lbs         | 59.75     | 17.65       | 6.69        |
| Strawberry | a.i./Acre       |           |             |             |
|            |                 |           |             |             |
|            | 1X Per Season   |           |             |             |
+------------+-----------------+-----------+-------------+-------------+
| North      | 350 lbs         | 1.67      | 0.48        | 0.18        |
| Carolina   | a.i./Acre       |           |             |             |
|            |                 |           |             |             |
| Sweet      | 1X Per Season   |           |             |             |
| Potato     |                 |           |             |             |
+------------+-----------------+-----------+-------------+-------------+
| North      | 350 lbs         | 1.45      | 0.46        | 0.18        |
| Carolina   | a.i./Acre       |           |             |             |
|            |                 |           |             |             |
| Tobacco    | 1X Per Season   |           |             |             |
+------------+-----------------+-----------+-------------+-------------+
| ^a^ Based  |                 |           |             |             |
| on 1-in-10 |                 |           |             |             |
| year       |                 |           |             |             |
| exceedance |                 |           |             |             |
| p          |                 |           |             |             |
| robability |                 |           |             |             |
| (0.10).    |                 |           |             |             |
+------------+-----------------+-----------+-------------+-------------+

Results of the 1-in-10 year probabilities are summarized in **Table 8**
and the full set of EECs are given in Appendix B.1.1 to B3.2. In
addition, the method for calculating a 1-in-10 year EEC is described in
Appendix B. The EECs presented in **Table 8** were used in this
ecological risk assessment.

The important output parameters for the modeling exercises are the peak,
21 day, and 60 day chloropicrin levels estimated in the model pond. The
highest EECs were observed for the Florida tomatoes and Florida
strawberries scenarios. The large variation of chloropicrin levels
estimated in surface waters can be traced to chemical loadings into the
environmental pond from the PRZM output. Since the chemical input
parameters are identical in each PRZM run, the different outputs are
entirely dependent upon the different soil parameters used in the
corresponding crop scenarios during the PRZM portion of the modeling
exercise, as well as the scenario-specific meteorological data. A much
higher percentage of pesticide was leached below the root zone level for
the North Carolina and California scenarios as compared to the Florida
scenarios due to a number of factors such as slope, soil type, moisture
content, and the runoff curve numbers used for the different fields.
This resulted in runoff and erosion flux vectors for the North Carolina
and California scenarios were considerably lower than those estimated
from the Florida tomatoes and Florida strawberries scenarios. As a
consequence, the chloropicrin loadings into the EXAMS model environment
were much lower, resulting in the smaller EECs.

***b. Aquatic Exposure Monitoring and Field Data***

Rapid volatilization of chloropicrin from water and soil surfaces is
expected to be an important route of dissipation from the environment.
Photolytic degradation of chloropicrin in water is also an important
route of dissipation. Since this compound is very soluble in water and
has low adsorption into soil, it can potentially leach into shallow
ground water and leaky aquifers, as well as, may transport to nearby
surface water through runoff and erosion, especially if chloropicrin
application coincides with, or is followed soon by a rain event.
Chloropicrin has been detected in the non-targeted monitoring wells.
Based on the data base of pesticides in groundwater (U.S. EPA, 1992),
chloropicrin was found at less than 1.00 μg/L in three wells from 15,175
wells in Florida.

**C. Ecological Effects Characterization**

Effects characterization describes the potential effects a pesticide can
produce in an aquatic or terrestrial organism. This characterization is
typically based on studies that describe acute and chronic effects
toxicity information for various aquatic and terrestrial animals and
plants. However, data for chloropicrin, while relatively extensive for
mammals, are very limited otherwise. Appendix C summarizes the results
of the toxicity studies used to characterize effects for this risk
assessment. Toxicity testing reported in this section does not represent
all species of birds, mammals, or aquatic organisms. Only a few
surrogate species for both freshwater fish and birds are used to
represent all freshwater fish (2000+) and bird (680+) species in the
United States. For mammals, acute studies are usually limited to Norway
rat or the house mouse. Estuarine/marine testing is usually limited to a
crustacean, a mollusk, and a fish. Also, neither reptiles nor amphibians
are tested. The risk assessment assumes that avian and reptilian
toxicities are similar. The same assumption is used for fish and
amphibians.

In general, categories of acute toxicity ranging from "practically
nontoxic" to "very highly toxic" have been established for aquatic
organisms (based on LC~50~ values), terrestrial organisms (based on
LD~50~ values), avian species (based on LC~50~ values), and non-target
insects (based on LD~50~ values for honey bees) (EPA 2001). These
categories are presented in Appendix C.

1\. Aquatic Effects Characterization

***a. Aquatic Animals***

The most sensitive acute toxicity references values associated with
chloropicrin exposure to aquatic organisms are summarized in **Table
9.** No chronic data are available. A more detailed summary of the
available aquatic toxicity data is given in Appendix C.

+--------+-----------+----------+---------------------+---------------+
| *      |           |          |                     |               |
| *Table |           |          |                     |               |
| 9.     |           |          |                     |               |
| Chloro |           |          |                     |               |
| picrin |           |          |                     |               |
| to     |           |          |                     |               |
| xicity |           |          |                     |               |
| ref    |           |          |                     |               |
| erence |           |          |                     |               |
| values |           |          |                     |               |
| (TRVs) |           |          |                     |               |
| (ppb   |           |          |                     |               |
| of     |           |          |                     |               |
| active |           |          |                     |               |
| ingre  |           |          |                     |               |
| dient) |           |          |                     |               |
| for    |           |          |                     |               |
| a      |           |          |                     |               |
| quatic |           |          |                     |               |
| organi |           |          |                     |               |
| sms.** |           |          |                     |               |
+========+===========+==========+=====================+===============+
| **Ex   | **        | **       | **Toxicity          | **Reference** |
| posure | Species** | Exposure | Reference Value     |               |
| Scen   |           | Du       | (ppb a.i.)**        |               |
| ario** |           | ration** |                     |               |
+--------+-----------+----------+---------------------+---------------+
| **Fres |           |          |                     |               |
| hwater |           |          |                     |               |
| Fish** |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| Acute  | Rainbow   | 48/96    | LC~50~ \< 16.98 ppb | FTLR 425      |
|        | trout     | hours    |                     |               |
|        |           |          | (very highly toxic) | Supplemental  |
|        |           |          |                     | Study         |
+--------+-----------+----------+---------------------+---------------+
| C      | NA        | NA       | NA                  | NA            |
| hronic |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| **Fres |           |          |                     |               |
| hwater |           |          |                     |               |
| Inv    |           |          |                     |               |
| ertebr |           |          |                     |               |
| ates** |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| Acute  | *Daphnia  | 48 hours | LC~50~ \<71 ppb     | MRID 130704   |
|        | pulex*    |          |                     |               |
|        |           |          | (very highly toxic) | Supplemental  |
|        |           |          |                     | Study         |
+--------+-----------+----------+---------------------+---------------+
| C      | NA        | NA       | NA                  | NA            |
| hronic |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| **Estu |           |          |                     |               |
| arine/ |           |          |                     |               |
| Marine |           |          |                     |               |
| Fish** |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| Acute  | NA        | NA       | NA                  | NA            |
+--------+-----------+----------+---------------------+---------------+
| C      | NA        | NA       | NA                  | NA            |
| hronic |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| **Estu |           |          |                     |               |
| arine/ |           |          |                     |               |
| Marine |           |          |                     |               |
| Inv    |           |          |                     |               |
| ertebr |           |          |                     |               |
| ates** |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| Acute  | NA        | NA       | NA                  | NA            |
+--------+-----------+----------+---------------------+---------------+
| C      | NA        | NA       | NA                  | NA            |
| hronic |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| **A    |           |          |                     |               |
| quatic |           |          |                     |               |
| Pl     |           |          |                     |               |
| ants** |           |          |                     |               |
+--------+-----------+----------+---------------------+---------------+
| Acute  | NA        | NA       | NA                  | NA            |
+--------+-----------+----------+---------------------+---------------+

NA = Data appropriate for quantitative use are not available.

*Acute Toxicity to Freshwater Fish*

The acute toxicity of chloropicrin to freshwater fish was evaluated in
rainbow trout and bluegill sunfish, with LC~50~s of \< 16.98 ppb (very
highly toxic) and \< 105 ppb (at least highly toxic), respectively. The
values are expressed as "less than" the numeric value, since
chloropicrin is highly volatile and measured residues were not provided.
The rainbow trout value is used as the toxicity value for assessing
acute risks to fish from exposure to chloropicrin.

*Acute Toxicity to Freshwater Invertebrates*

The acute toxicity of chloropicrin to aquatic invertebrates has been
assessed in *Daphnia pulex*, with a 48-hour LC~50~ value of \< 71 ppb
(very highly toxic). The value is expressed as "less than" the numeric
value, since chloropicrin is highly volatile and measured residues were
below the Level of Quantitation at the lowest four test levels at 48
hours. Although residues were below the Level of Quantitiation, 10 - 20%
mortality of daphnids occurred at these test levels.

***2. Terrestrial Effects Characterization***

***a. Terrestrial Animals***

The toxicity endpoints used to characterize risks of chloropicrin
exposure to birds and mammals are summarized in **Table 10.** Results of
all studies in terrestrial animal species are summarized in Appendix C.

+----------+----------+---------------+------------------+------------+
| **Table  |          |               |                  |            |
| 10.      |          |               |                  |            |
| Toxicity |          |               |                  |            |
| r        |          |               |                  |            |
| eference |          |               |                  |            |
| values   |          |               |                  |            |
| (TRVs)   |          |               |                  |            |
| for      |          |               |                  |            |
| ter      |          |               |                  |            |
| restrial |          |               |                  |            |
| species  |          |               |                  |            |
| for      |          |               |                  |            |
| chlorop  |          |               |                  |            |
| icrin.** |          |               |                  |            |
+==========+==========+===============+==================+============+
| **       | **S      | **Exposure    | **Toxicity**     | **R        |
| Exposure | pecies** | Duration**    |                  | eference** |
| Sc       |          |               | **Reference      |            |
| enario** |          |               | Value^1^**       |            |
+----------+----------+---------------+------------------+------------+
| **M      |          |               |                  |            |
| ammals** |          |               |                  |            |
+----------+----------+---------------+------------------+------------+
| Acute    | Rat      | Single oral   | LD~50~ = 37.5    | MRID       |
| oral     |          | dose          | mg/kg            | 05014376   |
|          |          |               |                  |            |
|          |          |               | (highly toxic)   | A          |
|          |          |               |                  | cceptable/ |
|          |          |               |                  | Guide-line |
+----------+----------+---------------+------------------+------------+
| Acute    | Rat      | 4-hour        | LC~50~ = 17 ppm  | MRID       |
| in       |          | inhalation    | (M) and 19 ppm   | 45117902   |
| halation |          |               | (F)              |            |
|          |          |               |                  | Acce       |
|          |          |               | \[conv. to mg/L: | ptable/Non |
|          |          |               | Section IV.B.2\] | -guideline |
+----------+----------+---------------+------------------+------------+
| Chronic  | Rabbit   | 6 hrs./day on | NOAEL = 0.4 ppm  | MRID       |
| in       |          | days 7 - 29   | (0.003 mg/L)     | 42740601   |
| halation |          | (inhalation)  |                  |            |
|          |          |               |                  | A          |
|          |          |               |                  | cceptable/ |
|          |          |               |                  | guideline  |
+----------+----------+---------------+------------------+------------+
| *        |          |               |                  |            |
| *Birds** |          |               |                  |            |
+----------+----------+---------------+------------------+------------+
| Acute    | No Data  |               |                  |            |
+----------+----------+---------------+------------------+------------+
| Chronic  | No Data  |               |                  |            |
+----------+----------+---------------+------------------+------------+
| ^1^Data  |          |               |                  |            |
| from     |          |               |                  |            |
| 9/30/04  |          |               |                  |            |
| and      |          |               |                  |            |
| 1/31/05  |          |               |                  |            |
| HED      |          |               |                  |            |
| Chlo     |          |               |                  |            |
| ropicrin |          |               |                  |            |
| Asse     |          |               |                  |            |
| ssments. |          |               |                  |            |
+----------+----------+---------------+------------------+------------+

> *Mammalian Species*

Based on the above results of an acute oral toxicity study in rats, EFED
considers chloropicrin to be highly toxic to mammals. The acute oral
value is used in this risk assessment only for the LD50 per square foot
preliminary analysis. The acute inhalation and chronic inhalation
endpoints are used for the inhalation analyses.

**IV. Risk Characterization**

**A. Risk Estimation - Integration of Exposure and Effects Data**

***1. Non-target Aquatic Animals and Plants***

There are uncertainties in estimating chloropicrin exposure in surface
water from post-application, due to tarping of the treated area. If
tarping is used to minimize the volatilization of chloropicrin, the
loading of the chemical through runoff will be limited until the tarp is
sliced or removed from the field. The present version of the PRZM model,
as well as the selected crop scenarios, has limited capabilities in
discounting the load from runoff of applied chemical under a
post-application tarp scenario. Since the load of chloropicrin from
runoff is considered in the PRZM/EXAMS simulation, the estimated
concentrations of chloropicrin in surface water bodies may be upper
bound. Therefore, PRZM/EXAMS estimated exposure values may contribute
upper bound LOCs for the aquatic organisms.

Risk quotients for aquatic animals are presented in **Table 11**. The
risk quotients are calculated using the toxicity values summarized in
**Table 9** and EECs from PRZM/EXAMS summarized in **Table 8**. For
assessing acute risks, the 24-hour peak concentration is used. Chronic
toxicity data are not available to calculated chronic risk quotients.

+-----------------+-----------+-----------------------+----------------+
| **Table 11.     |           |                       |                |
| Risk Quotients  |           |                       |                |
| (RQs) for       |           |                       |                |
| chloropicrin    |           |                       |                |
| for acute       |           |                       |                |
| exposures of    |           |                       |                |
| aquatic         |           |                       |                |
| species.**      |           |                       |                |
+=================+===========+=======================+================+
| **Exposure      | *         | **Toxicity Reference  | **Risk         |
| Scenario**      | *Exposure | Value (ppb)**         | Quotient^1^**  |
|                 | (ppb)**   |                       |                |
+-----------------+-----------+-----------------------+----------------+
| **Freshwater    |           |                       |                |
| Fish**          |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| Acute risk^2^   |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| California      | 3.66      | \<16.98               | \>0.22\*\*     |
| tomato          |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| California      | 2.14      | \<16.98               | \>0.12\*\*     |
| onion           |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| Florida tomato  | 107.80    | \<16.98               | \>6.35\*\*\*   |
+-----------------+-----------+-----------------------+----------------+
| Florida         | 59.75     | \<16.98               | \>3.52\*\*\*   |
| strawberry      |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| North Carolina  | 1.67      | \<16.98               | \>0.10\*\*     |
| sweet potato    |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| North Carolina  | 1.45      | \<16.98               | \>0.09\*       |
| tobacco         |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| **Freshwater    |           |                       |                |
| Aquatic         |           |                       |                |
| Invertebrates** |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| Acute risk^4^   |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| California      | 3.66      | \<71                  | \>0.05\*       |
| tomato          |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| California      | 2.14      | \<71                  | \>0.03         |
| onion           |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| Florida tomato  | 107.80    | \<71                  | \>1.52\*\*\*   |
+-----------------+-----------+-----------------------+----------------+
| Florida         | 59.75     | \<71                  | \>0.84\*\*\*   |
| strawberry      |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| North Carolina  | 1.67      | \<71                  | \>0.02         |
| sweet potato    |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| North Carolina  | 1.45      | \<71                  | \>0.02         |
| tobacco         |           |                       |                |
+-----------------+-----------+-----------------------+----------------+
| \*Exceeds acute |           |                       |                |
| endangered      |           |                       |                |
| species LOC     |           |                       |                |
| ([              |           |                       |                |
| \>]{.underline} |           |                       |                |
| 0.05)           |           |                       |                |
|                 |           |                       |                |
| \*\*Exceeds     |           |                       |                |
| acute           |           |                       |                |
| endangered      |           |                       |                |
| species LOC and |           |                       |                |
| acute           |           |                       |                |
| restricted use  |           |                       |                |
| LOC             |           |                       |                |
| ([              |           |                       |                |
| \>]{.underline} |           |                       |                |
| 0.1)            |           |                       |                |
|                 |           |                       |                |
| \*\*\*Exceeds   |           |                       |                |
| acute           |           |                       |                |
| endangered      |           |                       |                |
| species LOC,    |           |                       |                |
| acute           |           |                       |                |
| restricted use  |           |                       |                |
| LOC, and acute  |           |                       |                |
| risk LOC        |           |                       |                |
| ([              |           |                       |                |
| \>]{.underline} |           |                       |                |
| 0.5)            |           |                       |                |
+-----------------+-----------+-----------------------+----------------+

[Freshwater Fish and Invertebrates]{.underline}

As shown by the asterisks in the table above, all six of the scenarios
exceed at least one acute LOC, for fish and/or aquatic invertebrates
(based just on the numeric portion of the risk quotients shown). Given
that all risk quotients are expressed as "greater than" these numeric
values, all scenarios for both taxonomic groups could potentially exceed
LOCs. Whether or not they do will depend on future resolution of
definitive toxicity values.

Specifically, for freshwater fish, risk quotients exceed a) the
endangered species acute LOC (0.05) for all six scenarios, b) the
restricted use LOC (0.1) for all scenarios except North Carolina
tobacco, and c) the acute risk LOC (0.5) for Florida tomatoes and
Florida strawberries. For aquatic invertebrates, risk quotients exceed
a) the endangered species acute LOC (0.05) for California tomatoes,
Florida tomatoes, and Florida strawberries, and b) the restricted use
LOC (0.1) and the acute risk LOC (0.5) for Florida tomatoes and Florida
strawberries.

**2. Non-target Terrestrial Animals**

***a. Risk to Mammals***

EFED has used the established LD50/square foot risk assessment method
for mammals as a risk calculation screen. This method is considered to
cover all routes of exposure, although it uses an acute oral toxicity
value. It is typically used for granular and similar products, but it is
considered acceptable for use as a screen for chloropicrin.
Uncertainties of the method, in general, include 1) non-oral routes of
exposure may be either more or less hazardous than the oral route, and
2) an organism would not typically take up all the toxicant from any
given square foot, and the amount of toxicant in this unit of area may
be more or less than that which an organism receives overall as a dose.
For evaluating exposure to a highly volatile chemical applied below
ground, there is added uncertainty since all the chemical applied is not
available at the surface at any one time, for example. It's value for
the present assessment is as a preliminary screen to confirm whether a
refined route-specific (e.g., inhalation) analysis is appropriate. That
is, the LD50/square foot calculations reflect [all]{.underline} routes
of exposure. One then looks more closely at the individual routes of
exposure that are most appropriate (i.e., inhalation for fumigants) (E.
Odenkirchen, personal communication).

At 350 lb ai/A of chloropicrin, there would be 3,645 mg ai/square foot
(given 43,560 square feet/A and 453,590 mg/lb). This exposure amount is
divided by the product of acute oral LD50 for mammals (37.5 mg/kg) and
body weight of mammal (in kg) to calculate risk quotients. Three mammal
body weights are assessed: 15 g, 35 g, and 1000 g. The resulting risk
quotients (LD50s/sq. ft.) for these three sizes of mammals are 6,480;
2,777; and 97, respectively. These far exceed the acute risk LOC of 0.5,
as well as the acute restricted use LOC of 0.2 and the acute endangered
species LOC of 0.1. Thus, this preliminary screen indicates a potential
for concern for risk to wild mammals, and a need for further analysis.

The main route of wild mammal exposure is likely to be from inhalation
of chloropicrin off-gassing from treated fields. Mammalian inhalation
toxicity data are available. However, EFED does not currently have
established LOCs based on inhalation exposure. Nevertheless, an
inhalation risk concern for wild mammals has been identified. See the
Risk Description for the more refined assessment of risk based on
inhalation exposure.

***b. Risk to Avian Species***

The main route of exposure of birds is likely to be from inhalation of
chloropicrin off-gassing from treated fields. However, avian inhalation
data are not available. EFED has used the established LD50/square foot
method for mammals as a rough risk calculation screen (see above).
However, this screen has not been done for birds since the necessary
acute oral value for birds with chloropicrin is not available. See the
Risk Description for analysis of inhalation risk to mammals and how this
relates to potential risk to birds.

***3. Non-target Terrestrial and Semi-aquatic Plants***

Plant toxicity data \[123-1(a), 123-1(b)\] are needed for risk
assessment because of the potential for exposure and risk to exposed
terrestrial and semi-aquatic plants off-site.

**B. Risk Description**

***1. Risk to Aquatic Organisms***

*A. Animals*

Chloropicrin has the potential to reach surface water bodies. EECs to
determine the acute and chronic risk to aquatic organisms were estimated
using PRZM/EXAMS models with selected scenarios (CA tomatoes, CA onions,
FL tomatoes, FL strawberries, NC sweet potatoes, NC tobacco), to
represent the numerous crops for which chloropicrin is registered for
use. Although the same application rate of 350 lbs ai/A was used for all
scenarios, the chloropicrin exposure estimated resulted in different
risk potentials, due to the different conditions (e.g., rainfall, soil
temperature) for each modeled location. Also, for a given amount of
chloropicrin transported to a water body, there is expected to be
greater aquatic organism exposure in colder waters, since the Henry's
Law Constant will be lower in colder waters, resulting in lower
volatilization (and conversely, lower exposure in warmer waters).

Based on this exposure assessment: for fish, risk quotients are
considered to exceed a) the endangered species acute LOC (0.05) for all
six scenarios, b) the restricted use LOC (0.1) for all scenarios except
North Carolina tobacco, and c) the acute risk LOC (0.5) for Florida
tomatoes and Florida strawberries. For aquatic invertebrates, risk
quotients are considered to exceed a) the endangered species acute LOC
(0.05) for California tomatoes, Florida tomatoes, and Florida
strawberries, and b) the restricted use LOC (0.1) and the acute risk LOC
(0.5) for Florida tomatoes and Florida strawberries. In these cases, the
LOCs are exceeded based just on the numeric value of the risk quotients.
As explained earlier, given that all risk quotients are expressed as
"greater than" these numeric values, all scenarios for both taxonomic
groups could potentially exceed LOCs. Whether or not they do will depend
on future resolution of definitive toxicity values. Also, only a select
number of use sites have been modeled, and it is likely that other use
sites would have aquatic exposures in the range of those sites modeled.
Thus, it cannot be determined that any use site does not exceed acute
LOCs. However, in addition to the uncertainty concerning the toxicity of
chloropicrin to aquatic animals (i.e., chloropicrin is apparently more
toxic than indicated in the studies), there are also substantial
uncertainties concerning exposure modeling values, as described earlier.

In addition to the toxicity values used for risk quotients, a literature
search value for the mysid shrimp (257.8 ppb) was located via ECOTOX
(Carr, 1987). However, this reported value was based on a static test
without measured concentrations, unlike the submitted and reviewed
daphnid study where some measured concentrations were available. Also,
the reported mysid value is higher (i.e., implying lower toxicity) than
that available daphnid study (although with no confirmation of residues
at all in the mysid study, it is not possible to confirm what the
toxicity is). It is thus not used quantitatively in this screening
assessment.

***B. Plants***

Aquatic plant toxicity data (123-2) are needed for risk assessment
because of the potential for exposure and risk to aquatic plants
off-site.

***2. Risk to Terrestrial Organisms***

***A. Animals***

EFED's major concern with chloropicrin in the terrestrial environment is
that it is highly volatile and can off-gas from treated fields and
potentially expose a range of nontarget terrestrial organisms in its
path. Given the broad spectrum use of chloropicrin, it is assumed that
most living organisms in the treated fields (including any beneficial
insects and/or burrowing mammals) would be at high risk of mortality.

EFED used the screening-level LD50/ft^2^ method as a preliminary step to
assess risks of the pesticide to mammals. This method has most
frequently been applied to pesticide application scenarios involving
granular formulations, seed treatments, and baits. The method has not
been generally applied to situations involving highly volatile
compounds, but remains the Agency's most appropriate index for this type
of use. This LD50/ft^2^ method is an index that does not systematically
account for exposures from each potential route, but considers the
overall potential for adverse effects given a bioavailable amount of
pesticide conservatively related to the mass applied per unit area at
the treatment site. See the uncertainty discussion in the Risk
Estimation section above. Three mammal body weights are assessed: 15g,
35g, and 1000g. The resulting risk quotients for these three sizes of
mammals are 1,897, 813, and 28, respectively (see the Risk Estimation
section above). These far exceed the acute risk LOC of 0.5, as well as
the acute restricted use LOC of 0.2 and the acute endangered species LOC
of 0.1. Thus, this preliminary screen indicates a potential for concern
for risk to wild mammals, and a refined analysis based specifically on
inhalation exposure is described below.

Owing to the limitations of the the LD50/ft^2^ method for highly
volatile compounds and the recognized high potential volatility of
chloropicrin, EFED investigated the potential for inhalation to be a
toxicologically significant route of exposure to birds and mammals
within the use area. While data on inhalation toxicity are available for
mammals (from HED), inhalation toxicity data are not available for
birds.

Available ambient monitoring data for chloropicrin indicates a maximum
ambient air residue of 14,000 ng/m^3^ (see **Table 6**). This is
equivalent to a chloropicrin air concentration of 0.000014 mg/L. A
comparison of this air concentration with available mammalian acute
inhalation effects data (LC50 of 0.114 mg/L) would indicate a risk
quotient of 0.00012, well below any LOC.

Monitoring data for a limited number of application sites is not
necessarily predictive of all site conditions where the pesticide may be
used. Also, most monitoring data is for samples collected at least 1.0 m
above the ground, often higher. This height is above the level for many
ground-dwelling mammals and ground-feeding birds. It is reasonable to
assume a gradient of concentrations at the treatment site, with higher
concentrations of chloropicrin occurring closer to the ground. This
would be especially applicable to those times that a tarp is not used
(and animals would be more likely to be on the soil surface of the
treated field). Thus, modeling has been used to attempt to estimate
residues closer to the field and ground.

The ISCST3 model provides more flexibility compared to the monitoring
data (i.e., results are more easily extrapolated) and generally allows
the Agency to consider a much broader set of circumstances in its
assessments. Nevertheless, since EFED is relying on off-site monitoring
data, the model calculation does not specifically produce on-field,
ground surface level air residues. Because of uncertainties associated
with both monitoring and modeling, the Agency has calculated risk
estimates based on both, for comparison.

The ISCST3 model estimated concentrations were used in calculating the
concentrations on the edge of the field from a field application of
chloropicrin. The highest air concentration of 0.019 mg/L was estimated.
With an acute mammal inhalation LC50 of 17 ppm (0.114 mg/L), the risk
quotient for this modeled concentration is 0.17 (0.019 /0.114).

The Agency has not established level of concern (LOC) thresholds
expressly for the interpretation of RQs calculated for inhalation
exposure risks. However, if the existing LOC values for acute mammalian
wildlife risk were used to evaluated such RQs, the above analysis based
on modeling (risk quotient of 0.17) would suggest that at least some
uses of chloropicrin could exceed the acute endangered species LOC
(0.1), but not the acute restricted use LOC (0.2) or acute risk LOC
(0.5). The uncertainty level in these analyses can be reduced with
submission of ground-level monitoring data (e.g., 3 inches) both
within-field and edge-of-field, for maximum application rates.

The above assessment is limited to acute effects and exposure windows.
Wild mammals may have home ranges in the treatment area and may be
exposed continuously and/or repeatedly as the result of chloropicrin use
on multiple fields over multiple days in any geographic area. Given that
the rabbit inhalation developmental toxicity NOAEL for chloropicrin is
0.003 mg/L (with the developmental LOAEL of 0.008 mg/L based on
abortions and decreased fetal weights), lower than the acute inhalation
endpoint, EFED investigated the potential for a concern for chronic
exposure and effects. Given the short atmospheric half-life of
chloropicrin described earlier, it appears unlikely than long-term
exposure would occur from any single application of chloropicrin.
However, multiple fields may be treated in an area over a number of
days. Therefore, there still exists a potential that mammals within an
area of multiple treated fields may be exposed to chloropicrin emissions
on a repeated basis over time. Comparison of the previously cited
maximum ambient air residues (0.000014 mg/L) to the 0.003 mg/L NOAEL
above implies that ambient air residues are likely to be well below
developmental effect levels.

The above analysis is based on mammalian toxicity data for the
inhalation route. A similar analysis could be performed for birds, if
the necessary data were available. However, no inhalation toxicity data
for chloropicrin are available for birds. If acute toxicity by the oral
route were available for both mammals and birds, an evaluation of the
relative sensitivity via the oral route might be extrapolated to the
inhalation route to estimate an acute inhalation endpoint for birds.
However, no acute oral LD50 data for chloropicrin are available for
birds. Therefore, EFED is limited to an assumption of equivalent
sensitivity between birds and mammals for exposure through inhalation.
EFED feels that such an extrapolation may not be protective, given
higher respiration rates for birds versus mammals, and physiological
differences in the avian lung that would tend to favor higher diffusion
rates across the lung membrane when compared to mammals. Therefore,
inhalation analyses that suggest a potential for adverse effects in
mammals would also suggest potential risks to birds via the inhalation
route, but analyses not indicating risk to wild mammals would not
necessarily be true for birds also.

Although birds are mobile and some may only have a very brief exposure
flying by, others may have territories or nests in the area and be
exposed more substantially and/or repeatedly (in addition, eggs are gas
permeable and could be exposed). Repeat exposures can occur since
chloropicrin may be applied to different fields in a given geographic
area on different days. The uncertainty level can be reduced with this
screening-level analysis by submission of avian acute inhalation
toxicity data, in addition to the above-cited ground-level monitoring
data. A laboratory subchronic/chronic avian inhalation study will help
EFED address potential repeated exposure of birds over time in the wild.

***B. Plants***

Based on the phytotoxicity of chloropicrin on the treated fields, it is
expected that non-target plants off-site may also be a risk from
off-gassed chloropicrin. Terrestrial plant guideline toxicity data are
needed to evaluate this risk.

***3. Review of Incident Data***

Extremely limited terrestrial animal (non-human) incident data are
available for chloropicrin. For example, there was an incident in
Europe, in which a mis-labeled product that was later determined to
contain chloropicrin was inadvertently used in a greenhouse in
combination with metam sodium. It resulted in large numbers of domestic
animal deaths when the chloropicrin gas escaped to the surrounding area
(Selala, et. al. 1989). Although this incident does [not]{.underline}
reflect the expected exposure from labeled uses reviewed in the present
risk assessment, it does indicate the potential for hazard if
chloropicrin were to be mis-handled and get into the ground-level air at
high concentrations.

In an aquatic animal incident involving chloropicrin and telone
beginning 9/1/05, several thousand dead fish were reported over a 3-mile
reach of Casserly Creek in Santa Cruz County, California. The mortality
appeared to begin near a strawberry field being fumigated (using
chemigation) with the product Inline (R). Species killed included
steelhead/rainbow trout, sculpin, hitch, and Sacramento blackfish.
Crayfish were also killed (I-016955-001; 11/18/05 Pesticide Laboratory
Report, California Department of Fish and Game). Inline (R)
(Registration number 62719-348) is a 60.8 % telone/33.3 % chloropicrin
product. EFED is expected to assign a certainty level in the Ecological
Incident Information System (EIIS) of "highly probable" for chloropicrin
in this incident, based on the 11/18/05 report. The California Pesticide
Investigations Unit is checking further as to how the pesticide moved to
the stream. There is no mention of rain in the 11/18/05 report, the
applicator has cited a possible defective valve in a flush line
(I-016884), and the registrant has claimed that a valve was mistakenly
opened (I-016738-016).

Also, fish farm incidents have shown the potential for another
off-gassed fumigant, MITC (from agricultural application of
metam-sodium) to be inadvertently drawn into man-made aeration systems,
resulting in possible fish mortality. Based on the similar off-gassing
potential of chloropicrin, this same risk may apply to this chemical, if
it is applied to fields in the vicinity of fish farms with air intake
systems. Chloropicrin is heavier than air and could potentially travel
along the ground and be inadvertently drawn into such systems.

Three plant incidents involving fumigant products with chloropicrin as
one of the active ingredients have been identified in a 1/19/06 report
by M. Kathleen O'Malley (ITRMD/OPP). One of these involved the product
Telone C-35 (62719-302; 63.4% telone, 34.7% chloropicrin) and was coded
as major by ITRMD. The other two incidents were coded by ITRMD as minor:
one involved this same combination product with telone; the other
involved a combination product with methyl bromide (Tri-con 57/43
Preplant Soil Fumigant; 11220-4, 57% methyl bromide, 42.6%
chloropicrin). These incidents help confirm the EFED assumption that
chloropicrin has the potential to adversely affect non-target plants.

***4. Endocrine Disruption***

Chloropicrin does not appear to present a specific endocrine disruption
risk at present. Nevertheless, EPA is required under the FFDCA, as
amended by FQPA, to develop a screening program to determine whether
certain substances (including all pesticide active and other
ingredients) *\"may have an effect in humans that is similar to an
effect produced by a naturally occurring estrogen, or other such
endocrine effects as the Administrator may designate.\"* Following the
recommendations of its Endocrine Disruptor Screening and Testing
Advisory Committee (EDSTAC), EPA determined that there was a scientific
basis for including, as part of the program, the androgen and thyroid
hormone systems, in addition to the estrogen hormone system. EPA also
adopted EDSTAC's recommendation that the Program include evaluations of
potential effects in wildlife. For pesticide chemicals, EPA will use
FIFRA authority, and, to the extent that effects in wildlife may help
determine whether a substance may have an effect in humans, FFDCA
authority, to require the wildlife evaluations. As the science develops
and resources allow, screening of additional hormone systems may be
added to the Endocrine Disruptor Screening Program (EDSP). When the
appropriate screening and/or testing protocols being considered under
the Agency's EDSP have been developed, chloropicrin may be subjected to
additional screening and/or testing to better characterize effects
related to endocrine disruption.

***5. Federally Threatened and Endangered (Listed) Species Concerns***

***A. Action Area***

For listed species assessment purposes, the action area is considered to
be the area affected directly or indirectly by the Federal action and
not merely the immediate area involved in the action. At the initial
Level I screening assessment, broadly described taxonomic groups are
considered and thus conservatively assumes that listed species within
those broad groups are co-located with the pesticide treatment area.
This means that terrestrial plants and wildlife are assumed to be
located on or adjacent to the treated site, and aquatic organisms are
assumed to be located in a surface water body adjacent to the treated
site. The assessment also assumes that the listed species are located
within an assumed area which has the relatively highest potential
exposure to the pesticide, and that exposures are likely to decrease
with distance from the treatment area. Section II. B of this risk
assessment presents the pesticide use sites that are used to establish
initial collocation of species with treatment areas.

If the assumptions associated with the screening-level action area
result in RQs that are below the listed species LOCs, a \"no effect\"
determination conclusion is made with respect to listed species in that
taxa, and no further description of an action area is necessary.
Furthermore, RQs below the listed species LOCs for a given taxonomic
group indicate no concern for indirect effects upon listed species that
depend upon the taxonomic group covered by the RQ as a resource.

However, in situations where the screening assumptions lead to RQs in
excess of the listed species LOCs for a given taxonomic group, a
potential for a \"may affect\" conclusion exists and may be associated
with direct effects on listed species belonging to that taxonomic group
or may extend to indirect effects upon listed species that depend upon
that taxonomic group as a resource. In such cases, additional
information on the biology of listed species, the locations of these
species, fate and transport properties of the chemical, and the
locations of use sites could be considered to determine the extent to
which screening assumptions regarding an action area apply to a
particular listed organism. These subsequent refinement steps could
consider how this information would impact the action area for a
particular listed organism and may potentially include areas of exposure
that are downwind and downstream of the pesticide use site.

***B. Taxonomic Groups Potentially at Risk***

The Level I screening assessment process for listed species uses the
generic taxonomic group-based process to make inferences on direct
effect concerns for listed species. The first iteration of reporting the
results of the Level I screen is a listing of pesticide use sites and
taxonomic groups for which RQ calculations reveal values that meet or
exceed the listed species LOCs. In the majority of cases, the
screening-level risk assessment process reports RQ calculations for the
following broad taxonomic groupings:

1.  

Birds (also used as surrogate for terrestrial-phase amphibians and
reptiles)

2.  Mammals

3.  Freshwater fish (also used as a surrogate for aquatic phase
    amphibians)

4.  Freshwater invertebrates

5.  Estuarine/marine fish

6.  Estuarine/marine invertebrates

7.  Terrestrial plants

8.  Algae and aquatic plants

For chloropicrin, risk quotients could not be calculated for most of
these, due to a lack of data. There may also be taxonomic groups of
listed species for which screening tools are not fully developed nor
represented through surrogacy with existing tools. For example, there is
no RQ calculation process for terrestrial invertebrates. Since
chloropicrin is used to kill certain terrestrial invertebrates, it must
be assumed for a screening analysis that listed terrestrial
invertebrates may be directly adversely affected as well.

***1. Discussion of Risk Quotients***

Endangered Species LOCs are exceeded for wild mammals, fish, and aquatic
invertebrates based on acute risk quotients. Although guideline avian
toxicity data are not available, birds may be as sensitive as mammals.
The aquatic risk quotients are all indeterminate (\>) since the toxicity
values are indeterminate (\<). Thus, while some modeled site risk
quotients are clearly above endangered species LOCs (i.e., they are
above the LOC even without the \>), EFED cannot confirm that any site
definitely does not exceed a fish or aquatic invertebrate LOC.
Terrestrial invertebrates are target species and thus nontarget
terrestrial invertebrates may also be at risk. Plants on treatment sites
may be susceptible to chloropicrin and thus plants off-site may also be
susceptible to off-gassed chloropicrin. Should estimated exposure levels
occur in proximity to listed resources, the available screening level
information suggests a potential concern for direct acute effects on
listed wild mammals, birds, fish, aquatic invertebrates, terrestrial
invertebrates, and plants associated with soil fumigant sites.

***2. Probit Dose Response Relationship***

An analysis has been conducted of the probability of individual
mortality at an LOC of 0.1, the acute endangered species LOC for wild
mammals. It is recognized that extrapolation of very low probability
events is associated with considerable uncertainty in the resulting
estimates. The analysis uses the EFED spreadsheet IECv1.1.xls, developed
by EFED (USEPA, 2004).

For mammals, slope and and confidence interval information for the slope
were not reported in the Data Evaluation Record for MRID 45117902, an
acute inhalation study. Risk quotients in the ecological risk assessment
used the inhalation toxicity value for male rats, where there was only
one partial mortality. Since probit results are not possible with only
one partial mortality, a default slope of 4.5 and confidence interval of
2 to 9 are used for the individual mortality probability analysis. Based
on an assumption of a probit dose response relationship with a mean
estimated slope of 4.5, the corresponding estimated chance of individual
mortality associated with the listed species LOC of 0.1, the acute toxic
endpoint for wild mammals, is approximately one in 294,000. To explore
possible bounds to such estimates, the upper and lower values for the
mean slope estimate (2 - 9) were used to calculate upper and lower
estimates of the effects probability associated with the listed species
LOC. These values are approximately one in 44 and one in 10^16^ (default
limit of Excel reporting).

As previously indicated, the acute risk quotient for mammals is
estimated to be 0.14, based on modeling. This is slightly higher than
the mammal acute endangered species LOC of 0.1. Thus, the probability of
individual mortality at the predicted exposures used for the risk
quotients would also be higher than at the LOC.

Data are not adequate to calculate individual effect probabilities for
freshwater fish and aquatic invertebrates. This is due to a lack of
measured concentrations in the fish studies and uncertainties in the
measured concentrations in the daphnid study (in the lowest four
concentrations at 48 hours). Data are not available to calculate
individual effects for other taxonomic groups.

***C. Data Related to Under-represented Taxa***

Although the Level I screening assessment process relies on RQ
calculations that use toxicity endpoints selected from the most
sensitive species tested within broad taxonomic groups, there may be
situations in which additional effects data from one or more sources may
suggest that a given suite of listed taxa may be more or less sensitive
than suggested by the effects data used for RQ calculations. In these
circumstances, the screening level RQs are not changed, but effects data
more specific to listed species may be used to evaluate the extent to
which screening-level RQs adequately represent conclusions regarding
effects on specific listed taxa. However, this does not appear to apply
to chloropicrin.

***D. Implications of Sublethal Effects***

For mammals, adverse effects were seen in a variety of chronic
inhalation studies. The endpoint selected for ecological risk assessment
is the developmental NOAEC of 0.4 ppm in rabbits. Abortions and
decreased fetal weights occurred at the LOAEL of 0.8 ppm in this study.

Thus, it is expected that sublethal effects could be seen in listed
mammals, if exposed at levels comparable to those producing effects in
the lab.

***E. Indirect Effects Analysis***

The Agency acknowledges that pesticides have the potential to exert
indirect effects upon the listed organisms by perturbing forage or prey
availability or altering the extent and nature of nesting habitat, for
example. In conducting a screen for indirect effects, the Agency uses
the direct effects LOCs for each taxonomic group to make inferences
concerning the potential for indirect effects upon listed species that
rely upon non-endangered organisms in these taxonomic groups as
resources critical to their life cycle.

For chloropicrin, direct effect LOCs are exceeded for mammals, fish and
aquatic invertebrates, as indicated above. Birds may be as sensitive as
mammals. Also, since chloropicrin is intended to kill certain target
terrestrial invertebrates, it could also potentially have a direct
effect on nontarget terrestrial invertebrates. It also has some
phytotoxicity potential on treated sites, and thus, might also have some
potential for phytotoxicity off-site. In addition to these potential
direct effects, there may thus be a potential for indirect effects to
those listed species that are dependent upon mammals, birds, fish,
aquatic invertebrates, terrestrial invertebrates, and/or plants.

***F. Critical Habitat***

In the evaluation of pesticide effects on designated critical habitat,
consideration is given to the physical and biological features
(constituent elements) of a critical habitat identified by the U.S Fish
and Wildlife and National Marine Fisheries Services as essential to the
conservation of a listed species and which may require special
management considerations or protection. The evaluation of impacts for a
screening level pesticide risk assessment focuses on the biological
features that are constituent elements and is accomplished using the
screening-level taxonomic analysis (risk quotients, RQs) and listed
species levels of concern (LOCs) that are used to evaluate direct and
indirect effects to listed organisms.

The screening-level risk assessment has identified potential concerns
for indirect effects on listed species for those organisms dependant
upon mammals, birds, fish, aquatic invertebrates, terrestrial
invertebrates, and/or plants. In light of the potential for indirect
effects, the next step for EPA and the Service(s) is to identify which
listed species and critical habitat are potentially implicated.
Analytically, the identification of such species and critical habitat
can occur in either of two ways. First, the agencies could determine
whether the action area overlaps critical habitat or the occupied range
of any listed species. If so, EPA would examine whether the pesticide\'s
potential impacts on non-endangered species would affect the listed
species indirectly or directly affect a constituent element of the
critical habitat. Alternatively, the agencies could determine which
listed species depend on biological resources, or have constituent
elements that fall into, the taxa that may be directly or indirectly
impacted by the pesticide. Then EPA would determine whether use of the
pesticide overlaps the critical habitat or the occupied range of those
listed species. At present, the information reviewed by EPA does not
permit use of either analytical approach to make a definitive
identification of species that are potentially impacted indirectly or
critical habitats that is potentially impacted directly by the use of
the pesticide. EPA and the Service(s) are working together to conduct
the necessary analysis.

This screening-level risk assessment for critical habitat provides a
listing of potential biological features that, if they are constituent
elements of one or more critical habitats, would be of potential
concern. These correspond to the taxa identified above as being of
potential concern for indirect effects and includes mammals, birds,
fish, aquatic invertebrates, terrestrial invertebrates, and/or plants.
This list should serve as an initial step in problem formulation for
further assessment of critical habitat impacts outlined above, should
additional work be necessary.

***G. Co-occurrence Analysis***

The goal of the analysis for co-location is to determine whether sites
of pesticide use are geographically associated with known locations of
listed species. At the screening level, this analysis is accomplished
using the LOCATES database. The database uses location information for
listed species at the county level and compares it to agricultural
census data for crop production at the same county level of resolution.
The product is a listing of federally listed species that are located
within counties known to produce the crop upon which the pesticide will
be used. Because the Level I screening assessment considers [**both**
direct and indirect effects]{.mark} across generic taxonomic groupings,
it is not possible to exclude any taxonomic group from a LOCATES
database run for a screening risk assessment.

Because chloropicrin is registered for preplant use on all "terrestrial
food crops" (as well as ornamental and other sites), essentially all use
sites from LOCATES would have to be selected. As indicated above, for a
screen for both direct and indirect effects, all taxonomic groups would
also have to be selected. Thus, a printout would essentially include all
known federally-listed species for all taxonomic groups in all counties
with agriculture. If the registrants are able to limit labels to a more
narrow set of crops, a more narrow set of counties and species can be
developed. If this is not done, the species-specific analysis will have
to include virtually all known federally-listed species for all
taxonomic groups in all counties with agriculture.

The registrants must provide information on the proximity of
federally-listed mammals, birds, fish, aquatic invertebrates,
terrestrial invertebrates, and plants to the registered use sites. This
requirement may be satisfied in one of three ways: 1) having membership
in the FIFRA Endangered Species Task Force (Pesticide Registration
\[PR\] Notice 2000-2); 2) citing FIFRA Endangered Species Task Force
data; or 3) independently producing these data, provided the information
is of sufficient quality to meet FIFRA requirements. The information
will be used by the OPP Endangered Species Protection Program to develop
recommendations to avoid adverse effects to listed species.

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**VI. Appendices**

**Appendix A. Environmental Fate and Transport Data**

**161-1 Hydrolysis (MRID# 43022401)**

Chloropicrin, at approximately 100 ppm, did not hydrolyze in sterile
aqueous buffered solutions adjusted to pH 5, 7, and 9, that were
incubated in the dark at 25̊C.During the 28 day study, chloropicrin
ranged from 106.4 to 113.8 ppm in the pH 5 acetate buffer solution, from
97.3 to 113.7 ppm in the pH 7 phosphate buffer solution, and from 101.6
to 111.1 ppm in the pH 9 phosphate buffer solution. No pattern of
decline was noted in any set of samples. In all samples, inorganic
chloride was \<1.5 ppm. The pH of the buffer solutions remained stable
throughout the study.

**161-2 Aqueous Photolysis (MRID# 42900201)**

This study provides very limited supplemental information. A new study
is required. However, the study provides some information about the
nature of the photolysis products of chloropicrin. Major problems were
found in this study related to the material balance.

Chloropicrin, at 164 mg/L, photodegraded with a registrant-calculated
half-life of 31.1 hours (1.29 days) in sterile aqueous solutions
buffered at pH 7 at 25̊C, irradiated with a xenon arc lamp (at about
twice the intensity of natural sunlight in April in Hollister,
California) on a 12 hour photoperiod. In contrast, the dark controls did
not appear to hydrolyze substantially during the test period.

hv

CCl~3~NO~2~ \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--\> 3Cl^-^ +
NO~2~^-^ + NO~3~^-^ + CO~2~ + H^+^

H~2~O (HCO~3~^-^ + CO~2~^2-^)

Chloride increased to up to 0.00240 M (80%) after 108 hours. CO~2~
increased to up to 0.000143 M (14.3%) after 108 hours. The bicarbonate
ion increased to 0.000573 M after 108 hours. Other products were nitrate
and nitrite, at maximum of 0.000347 M and 0.000143 M, at 108 hours,
respectively. The chloride ion reached 0.00205 M after 108 hours.

**161-3 Photodegradation on Soil (Waived)**

This study was waived because chloropicrin is used by soil injections,
therefore, no substantial soil photolysis is expected.

**161-4 Photolysis in Air (MRID# 05007865)**

The photolytic half-life of chloropicrin vapor is about 20 days at
25-30̊C. The photolysis rate decreased markedly after 20 days. The
photodegradation appears to be dependent on the presence of oxygen. The
initial photoproducts and the incorporation of ^18^O~2~ suggest an
intramolecular rearrangement involving the trioxazole N-oxide as an
intermediate. In the dark control, the concentration of chloropicrin
decreased slightly over 70 days.

Chloropicrin vapor is readily photodegraded to phosgene (COCl~2~) and
nitrosyl chloride (NOCl) under simulated sunlight. COCl~2~ is not
further degraded, but NOCl subsequently is photodegraded to nitrous
oxide (NO) and chlorine (Cl~2~). A portion of the NO is oxidized to
nitrogen dioxide (NO~2~) and dinitrogen tetraoxide (N~2~O~4~).

A degradation pathway was postulated by the registrant: In nitrogen
atmosphere, chloropicrin was stable to irradiation, indicating that O~2~
is required for photodecomposition, and suggesting that an intermediate,
trioxazole N-oxide, was involved, that decomposes to COCl~2~, NOCl, and
O~2~.

![](media/image7.emf){width="4.273611111111111in"
height="3.9590277777777776in"}

**162-1 Aerobic Soil Metabolism (MRID# 43613901)**

This aerobic soil metabolism study is scientifically valid and provides
useful information on the aerobic soil metabolism of chloropicrin. The
study is acceptable as it followed the previously approved protocol for
the data requirement. No new study is required.The registrant is
required to address the following problems found in the study:

1.  Maintenance of aerobic conditions and moisture at the water holding
    capacity (WHC) throughout the experiment;

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1.  Effects of chloropicrin on soil viability;

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1.  Location of the PUF trap in relation to the KOH trap; and

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1.  The target thickness, in inches, of the soil to be treated in th
    field and its vertical location in the soil profile.

\[^14^C\]chloropicrin, at nominal application rates of 310-329 ppm, or
equivalent field rates of nearly 550-600 lb a.i/acre, degraded in the
laboratory with calculated half-life of 8 to 11 days in Baywood sandy
loam soil adjusted to 78% of 0.33 bar moisture and incubated in the dark
at 25±1^o^C for up to 21 and 24 days.

The study was performed using three samples sets which were not treated
at the same rate or incubated simultaneously. The study indicates that
biotic transformation into CO~2~ is the most important process that had
governed the fate of chloropicrin under the stated laboratory
conditions. Initially, parent escaped biodegradation by volatilization
but later was subject to biodegradation and to binding, into the soil,
in a non-extractable form.

Evolved ^14^CO~2~ increased to 72.2% at 24 days posttreatment.
Chloronitromethane, nitromethane, and bicarbonate were the only three
minor degradates identified (a total of \<6% of the applied
radioactivity). Degradates were formed by substitution of Cl by H and
were mainly detected in association with the soil in extractable and
later in nonextractable forms.

This aerobic soil study was conducted without supplying the system with
continuous flow to remove volatile materials. This type of system do not
closely mimic field condition where volatilized materials are relatively
free to escape.

Reexamination of the study results reveals that volatilization, in the
soil environment, will be the major dissipation route of chloropicrin.
Due to the fact that volatilization is significant and occurs rapidly,
the importance of other competing processes such as leaching,
biodegradation, and adsorption to the soil particles will certainly
depend on expected field volatility. This is because volatility
determines the amount of chloropicrin left for other processes and its
residence time in the soil system.

**162-3 Anaerobic Aquatic Metabolism (MRID# 43759301, supplemental)**

This study provides useful supplemental information about the anaerobic
aquatic metabolism of chloropicrin. The study does not meet Subdivision
N Guidelines for the fulfillment of EPA data requirements for the
following reasons:

1.  The test water was not representative of that found at an intended
    use site (purified deionized water was utilized to flood the soil
    samples).

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1.  The analytical methods were inadequate for the characterization of
    residues in water samples removed at later sampling intervals. The
    HPLC column recoveries for the water phase samples were 103-104% at
    0-1.5 hours posttreatment, decreased to 83.6% by 5 days
    posttreatment, and were 24.1% at 54 days posttreatment. The study
    authors did not provide an explanation for this decrease.

Radiolabeled \[^14^C\]chloropicrin, at a nominal application rate of 313
± 14.4 µg/g, degraded with a calculated half-life of 1.3 hours (r^2^ =
1.0; 0- to 4-hour data only) in anaerobic flooded sandy loam soil that
was incubated in darkness at 25 ± 1̊C for up to 54 days.

All data are reported as percentages of the nominal application.
Degradate data are reported in parent equivalents. The parent was
initially present in the total soil/water system at 96.3% of the applied
radioactivity, decreased to 45.5% by 1.5 hours and 11.2% by 4 hours, was
1.7-2.2% at 1-2 days, was not detected from 5 to 12 days, and was last
detected at 0.1% (one of two replicates) at 26 days posttreatment. The
parent was mostly associated with the water phase.

The major degradate nitromethane was a maximum of 53.4% at 1 day, and
was last detected at 16.9% (one of two replicates) at 26 days
posttreatment.

The major degradate chloronitromethane increased to 51.5% by 4 hours,
and was last detected at 0.1% (one of two replicates) at 54 days
posttreatment.

Nonextractable \[^14^C\]residues increased to a maximum of 32.0% at 54
days posttreatment; \[^14^C\]residues associated with the fulvic and
humic acid fractions were 24.4% and 1.3% of the applied, respectively,
at 54 days posttreatment.

\[^14^C\]Volatiles in the KOH traps reached 45.7% at 54 days
posttreatment. Based on BaCl~2~ precipitation of KOH traps, evolved
^14^CO~2~ accounted for 4.1% at 54 days posttreatment.

\[^14^C\]Organic volatiles were a maximum of 8.8% of the applied
radioactivity at 1.5 hours, were 2.5-4.9% at 1-5 days, and were 0.6% at
54 days posttreatment. Based on HPLC analysis of the foam plug extract,
the parent accounted for 8.1% of the applied radioactivity at 1.5 hours
and was 1.1-1.8% at 1-2 days posttreatment. Radioactivity in the
headspace was 10.9% of the applied radioactivity at 1.5 hours and was
0.1-0.7% at 1-54 days posttreatment; the parent accounted for 10.7% of
the applied at 1.5 hours posttreatment.

**163-1 Mobility - Column Leaching (MRID# 44191301)**

This study is considered acceptable and it meets Subdivision §N
Guidelines for the fulfillment of the mobility data requirement (column
leaching) of chloropicrin. However, data were variable for the silty
clay loam soil and the loamy sand soil, precluding definitive mobility
determinations for the compound in those soils.

The column leaching of \[^14^C\]chloropicrin, at a nominal rate
equivalent to 345 lb/A or 362 lb/A was studied in sandy loam, loamy
sand, silt loam, and silty clay loam soil columns which were leached
with CaCl~2~ over a period of 17-138 hours, 1-1.5 hours, 126-132 hours,
and 101-116 hours, respectively. Based on the results of this study, it
was observed that chloropicrin is very mobile in all four soils tested.

In the Baywood sandy loam soil, most of the \[^14^C\]residues retained
in the soil column following leaching were detected in the 30- to 36-cm
(4.6%), 36- to 42-cm (5.7%), and 42- to 48-cm (5.7%) depths. The parent
was 4.0% of the applied radioactivity in the 12- to 24-cm depth (12- to
18-cm and 18- to 24-cm depths combined), was 6.9% in the 24- to 36-cm
depth (24- to 30-cm and 30- to 36-cm depths combined), and was 11.2% in
the 36- to 48-cm depth (36- to 42-cm and 42- to 48-cm depths combined).
The minor degradates dichloronitromethane, and nitromethane were
detected once each. Nonextractable \[^14^C\]residues were 1.0% of the
applied radioactivity in the 12- to 18-cm depth, and were 0.4-0.5% in
each of the 18- to 24-cm, 30- to 36-cm, 36- to 42-cm, 24- to 30-cm, and
42- to 48-cm depths. Total \[^14^C\]residues in the leachate solution
were 30.8% of the applied radioactivity. The parent was 17.2% of that
radioactivity; the minor degradates dichloromethylhydroxylamine,
dichloronitromethane, and nitromethane were ≤7.3% of the applied
radioactivity. \[^14^C\]Organic volatiles (bottom of the column) were
32.8% of the applied radioactivity; the parent accounted for 32.4% of
the applied.

In the Baywood loamy sand soil, most of the \[^14^C\]residues retained
in the soil column following leaching were detected in the 12- to 18-cm
(22.6%) depth. The parent was 36.6% (two of three columns) of the
applied radioactivity in the 12- to 24-cm depth (12- to 18-cm and 18- to
24-cm depths combined) and was 8.6% (two of three columns) in the 24- to
48-cm depth (24- to 30-cm, 30- to 36-cm, 36- to 42-cm, and 42- to 48-cm
depths combined). Degradates were not detected. Nonextractable
\[^14^C\]residues were 0.1% of the applied radioactivity in each of the
18- to 24-cm, 24- to 30-cm, 30- to 36-cm, 36- to 42-cm, and 42- to 48-cm
depths. Total \[^14^C\]residues in the leachate solution were 43.7% of
the applied radioactivity. The parent was 42.7% of the applied
radioactivity. The minor degradates dichloronitromethane and
dichloromethyl hydroxylamine were each ≤0.77% of the applied
radioactivity. \[^14^C\]Organic volatiles (bottom of the column) were
12.2% of the applied radioactivity; the parent accounted for 12.2% of
the applied.

In the Congaree silt loam soil, most of the \[^14^C\]residues retained
in the soil column following leaching were detected in the 36- to 42-cm
(6.6%) and 42- to 48-cm (6.9%) depths. The parent was 0.1% of the
applied radioactivity in each of the 12- to 30-cm (combined), 30- to
42-cm (combined), and 42- to 48-cm depths. The minor degradates
dichloromethylhydroxylamine, dichloronitromethane, and nitromethane were
detected at ≤0.1% of the applied radioactivity. Nonextractable
\[^14^C\]residues were 0.4% of the applied radioactivity in the 6- to
12-cm depth, were 2.5-4.5% in each of the 12- to 18-cm, 18- to 24-cm,
and 24- to 30-cm depth, and were 5.0-5.7% in each of the 30- to 36-cm,
36- to 42-cm, and 42- to 48-cm depths; \[^14^C\]residues associated with
the humic acid, fulvic acid, and humin fractions of a selected soil
column were 0.19-0.38%, 0.94-2.8%, and 1.9-4.1% of the applied,
respectively, in each of the 12- to 18-cm, 18- to 24-cm, 24- to 30-cm,
30- to 36-cm, 36- to 42-cm, and 42- to 48-cm depths. Total
\[^14^C\]residues in the leachate solution were 31.6% of the applied
radioactivity. The parent was 1.1% of the applied radioactivity. The
major degradate dichloromethylhydroxylamine was 16.4% of the applied
radioactivity. The major degradate dichloronitromethane was 10.9% of the
applied radioactivity. The minor degradate nitromethane was 2.5% of the
applied radioactivity. \[^14^C\]Organic volatiles (bottom of column)
were 17.8% of the applied radioactivity; the parent and
dichloronitromethane accounted for 13.8% and 3.3% of the applied,
respectively.

In the Lowell silty clay loam soil, most of the \[^14^C\]residues
retained in the soil column following leaching were detected in the 12-
to 18-cm (24.3%) depth. Characterization data were variable between the
two soil columns. In Column 1, the parent was 0.1% of the applied
radioactivity in each of the 12- to 30-cm, 30- to 42-cm, and 42- to
48-cm depths. In Column 2, the parent was 49.3% of the applied
radioactivity in the 12- to 24-cm depth, was 1.3% in the 24- to 36-cm
depth, and was not detected in the 36- to 48-cm depth. The minor
degradates dichloronitromethane, and dichloromethylhydroxylamine were
≤1.5% of the applied radioactivity. Nonextractable \[^14^C\]residues
were ≤2.2% of the applied radioactivity in each of the soil depth from
6- to 42-cm; \[^14^C\]residues associated with the humic acid, fulvic
acid, and humin fractions of combined soil columns (12 to 48-cm depth)
were 0.5%, 6.3%, and 6.0% of the applied, respectively. Total
\[^14^C\]residues in the leachate solution were 20.5% of the applied
radioactivity. The parent compound was present at 1.5% (one of two
column leachates) of the applied radioactivity. The major degradate
dichloronitromethane was 12.0% of the applied radioactivity. The minor
degradates dichloromethylhydroxylamine, and nitromethane were ≤5.5% of
the applied radioactivity. \[^14^C\]Organic volatiles (bottom of column)
were 19.4% of the applied radioactivity; the parent accounted for 14.5%
(one of two columns) of the applied. The major degradate
dichloronitromethane was detected at 10.3% of the applied radioactivity.
The minor degradate nitromethane was 1.5% of the applied radioactivity.
The minor degradate dichloromethyl-hydroxylamine was 0.6% of the applied
radioactivity.

**163-2 Laboratory Volatility (MRID# 43798601)**

This study is acceptable as it meets Subdivision N Guidelines for the
fulfillment of EPA data requirements on laboratory volatility. This
laboratory volatility study is scientifically valid. It provides useful
information on the volatility of chloropicrin in a sandy loam soil.
However, it appears that the flow exchange rate is high compared to
actual use conditions.

The registrant is required to address the following:

1.  Time zero analysis of treated soil was not conducted;

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1.  Was the trapping efficiencies of charcoal, methanol, and KOH traps
    determined? if so give the results.

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1.  Need to relate the 100 mL/min flow rate or corresponding air
    changes/hr to total exchanges during actual practice under
    greenhouse, and field conditions (specified wind speeds).

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1.  Limits of detection were reported but limits of quantitation were
    not;

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1.  What is the vapor pressure at 25 ^o^C? Other references give 23.8 mm
    Hg; Is this accurate?

Although \[^14^C\]chloropicrin was applied through sub-surface
injection, it volatilized within few to nearly 30 hours from non-tarped
and tarped soil surfaces, respectively. By the end of the 8-day
laboratory experiment, 80-87% of the applied parent volatilized from the
soil surface as parent, 5-8% volatilized as CO~2~, 5-7% bound to the
soil, and \<1% degraded into chloronitromethane. The results indicate
that volatilization as parent, is expected to be the most important
route of dissipation for chloropicrin in the soil environment. Data on
non-tarped and tarped covered soil surfaces indicate that covering the
soil surface with plastic tarp caused a change in the pattern and rates
of volatilization during the first 60 hours of the experiment.

\[^14^C\]chloropicrin, at a nominal application rate of 300 ppm,
volatilized from sandy loam soil (uncovered and tarp-covered) adjusted
to 60% of 0.33 bar soil moisture content and incubated in darkness at
25.0 ± 1̊C for up to 8 days with an air flow (\>90% relative humidity)
rate of approximately 100 mL/min.

In the uncovered (no tarp) soil, the maximum volatility of the parent
was 342 µg/cm^2^/hr and the maximum air concentration of the parent was
1.0 × 10^4^ µg × 10^3^/m^3^ (2-6 hour interval). Total
\[^14^C\]volatiles accounted for 92.6% of the applied radioactivity at 8
days posttreatment. Organic \[^14^C\]volatiles detected in the methanol,
water vapor, and charcoal traps were 86.0%, 1.5%, and 0.08% of the
applied radioactivity, respectively, at 8 days posttreatment; evolved
^14^CO~2~ was 5.1% of the applied. The parent was initially (2 hours)
present in the methanol trap at 0.8% of the applied radioactivity,
increased to 16.3% by 6 hours and 65.4% by 24 hours, and was 81.5-85.5%
at 46-116 hours posttreatment. The degradate dichloronitromethane was
detected in the methanol trap at 0.4% of the applied radioactivity. In
the soil, extractable and nonextractable \[^14^C\]residues were 0.4% and
4.3% of the applied radioactivity, respectively, at 8 days
posttreatment.

In tarp covered soil, the pesticide stayed within the soil system for
relatively longer period of time than in non-tarped soil. This resulted
in a slightly higher pesticide bio-degradation and binding to the tarped
compared to non-tarped soil as inferred from the observed higher
concentrations of CO~2~ and soil bound residue. In the tarp-covered
soil, the maximum volatility of the parent was 205 µg/cm^2^/hr and the
maximum air concentration of the parent was 5918 µg × 10^3^/m^3^ (23-25
hour interval; interval in which the tarp was punctured). Total
\[^14^C\]volatiles accounted for 89.3% of the applied radioactivity at 8
days posttreatment. Organic \[^14^C\]volatiles detected in the methanol,
water vapor, and charcoal traps were 79.9%, 1.2%, and 0.09% of the
applied radioactivity, respectively, at 8 days posttreatment; evolved
^14^CO~2~ was 8.2% of the applied. The parent was initially (4 hours)
present in the methanol trap at 1.9% of the applied radioactivity,
increased to 38.7% by 23 hours and 67.2% by 47 hours, and was 79.1% at
144 hours posttreatment. The degradate dichloronitromethane was detected
in the methanol trap at 0.7% of the applied radioactivity. In the soil,
extractable and nonextractable \[^14^C\]residues were 1.1% and 6.1% of
the applied radioactivity, respectively, at 8 days posttreatment.

**164-1 Terrestrial Field Dissipation (MRID# 43085101, supplemental)**

This study provides limited supplemental information about the
terrestrial field dissipation of chloropicrin. Several problems were
found in the study:

1.  samples were taken only of the soil air and analyzed only for
    chloropicrin (and methyl bromide), no soil samples were taken;

2.  the test soils were not completely characterized;

3.  the site description was incomplete and not adequately
    characterized;

4.  the field maintenance practices used before and after application
    were not provided.

Chloropicrin dissipated with half-lives of 11.6, 16.4, and 33.4 hours
from the soil air at the 3-, 6-, and 12-inch depths, respectively,
following treatment with 665 lb a.i./A chloropicrin (TRI-CLOR: 99%
purity) of a tarped clay loam soil in California in July, 1987. The
chloropicrin was applied by chisel injection at a depth of 6-8 inches,
the soil surface was covered with a polyethylene tarp for 48 hours, and
sampling was initiated after removal of the tarp. Chloropicrin was found
at maximum concentration of 755-781 ppm in the soil air from the upper
12 inches at 51 hours posttreatment (3 hours after removal of the tarp).
Concentrations at the 24-, 36-, and 48-inch depths were never exceeded
30, 8.6, and 5.8 ppm, respectively, and declined to below background
levels by the termination of the study (291 hours posttreatment).
Background levels of chloropicrin (as determined by analysis of soil air
from the untreated check plot located 15 feet away from the treated
plot) ranged from 0.2 to 8.5 ppm (average 2.9 ppm).

Chloropicrin dissipated with half-lives of 18.0, 20.3, and 28.7 hours
from the soil air at the 3-, 6-, and 12-inch depths, respectively,
following treatment with 792 lb a.i./A chloropicrin (TRI-CLOR: 99%
purity) of a tarped sand soil in California in August, 1987. The
chloropicrin was applied by chisel injection at a depth of 6-8 inches,
the soil surface was covered with a polyethylene tarp for 48 hours, and
sampling was initiated after removal of the tarp. Chloropicrin was found
at maximum concentrations of 554.0, 930.0, and 1185.0 ppm in the 3-, 6-,
and 12-inch soil depths, respectively, at 51 hours posttreatment (3
hours after removal of the tarp). Concentrations at the 24-, 36-, and
48-inch depths increased to a maxima of 593.0, 230.5, and 75.2 ppm,
respectively; times of maximum concentration were 12, 12, and 48 hours,
respectively, after removal of the tarp. By the termination of the study
(240 hours posttreatment), concentrations at 24-, 36-, and 48-inch
depths had decreased to 31.8, 37.1, and 16.8 ppm, respectively.
Background levels of chloropicrin (as determined by analysis of soil air
from the untreated check plot located 15 feet away from the treated
plot) ranged from 0.3 to 8.5 ppm (average 1.9 ppm).

**Appendix B. Aquatic Exposure PRZM/EXAMS Modeling**

This appendix documents the output from PRZM / EXAMS simulations for
each of six location/crop scenarios: California / Onion and Tomato,
Florida / Strawberry and Tomato, and North Carolina / Tobacco and sweet
potato. The settings for each model run are presented first, followed by
the raw data sorted by year and sorted in descending order by EEC.
Values represent the estimated environmental concentrations (EECs) in
units of micrograms per liter (μg/L) or parts per billion (ppb). The
1-in-10 year summary statistics for each run are presented at the very
end of the sorted results in the row assigned a probability level of
0.10. This summary statistic was generated from a linear interpretation
of the raw data plotted using Weibull plotting positions. This approach
is further described at the end of the appendix B-6.

**B.1.1 Florida Strawberry**

+---------+---------+---------+---------+---------+---------+---------+
| stored  |         |         |         |         |         |         |
| as      |         |         |         |         |         |         |
| FLStr   |         |         |         |         |         |         |
| awb.out |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Ch      |         |         |         |         |         |         |
| emical: |         |         |         |         |         |         |
| Chlor   |         |         |         |         |         |         |
| opicrin |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| PRZM    |         |         |         |         |         |         |
| envir   |         |         |         |         |         |         |
| onment: |         |         |         |         |         |         |
| Flst    |         |         |         |         |         |         |
| rawberr |         |         |         |         |         |         |
| yC.txt, |         |         |         |         |         |         |
| M       |         |         |         |         |         |         |
| odified |         |         |         |         |         |         |
| Monday, |         |         |         |         |         |         |
| 30 June |         |         |         |         |         |         |
| 2003 at |         |         |         |         |         |         |
| 0       |         |         |         |         |         |         |
| 8:19:10 |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| EXAMS   |         |         |         |         |         |         |
| envir   |         |         |         |         |         |         |
| onment: |         |         |         |         |         |         |
| pond2   |         |         |         |         |         |         |
| 98.exv, |         |         |         |         |         |         |
| M       |         |         |         |         |         |         |
| odified |         |         |         |         |         |         |
| Thuday, |         |         |         |         |         |         |
| 29      |         |         |         |         |         |         |
| August  |         |         |         |         |         |         |
| 2002 at |         |         |         |         |         |         |
| 1       |         |         |         |         |         |         |
| 6:33:30 |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| M       |         |         |         |         |         |         |
| etfile: |         |         |         |         |         |         |
| w128    |         |         |         |         |         |         |
| 42.dvf, |         |         |         |         |         |         |
| M       |         |         |         |         |         |         |
| odified |         |         |         |         |         |         |
| Wedday, |         |         |         |         |         |         |
| 3 July  |         |         |         |         |         |         |
| 2002 at |         |         |         |         |         |         |
| 0       |         |         |         |         |         |         |
| 9:04:28 |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| **Water |         |         |         |         |         |         |
| segment |         |         |         |         |         |         |
| concent |         |         |         |         |         |         |
| rations |         |         |         |         |         |         |
| (ppb)** |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Year    | Peak    | 96 hr   | 21 Day  | 60 Day  | 90 Day  | Yearly  |
+---------+---------+---------+---------+---------+---------+---------+
| 1961    | 4.62    | 3.11    | 1.38    | 0.57    | 0.39    | 0.10    |
+---------+---------+---------+---------+---------+---------+---------+
| 1962    | 84.41   | 57.97   | 21.99   | 8.16    | 5.45    | 1.34    |
+---------+---------+---------+---------+---------+---------+---------+
| 1963    | 33.19   | 22.05   | 8.17    | 3.42    | 2.30    | 0.57    |
+---------+---------+---------+---------+---------+---------+---------+
| 1964    | 3.16    | 2.18    | 1.15    | 0.53    | 0.36    | 0.09    |
+---------+---------+---------+---------+---------+---------+---------+
| 1965    | 104.00  | 69.55   | 26.30   | 9.81    | 6.55    | 1.62    |
+---------+---------+---------+---------+---------+---------+---------+
| 1966    | 5.05    | 3.58    | 2.12    | 0.91    | 0.61    | 0.15    |
+---------+---------+---------+---------+---------+---------+---------+
| 1967    | 6.91    | 4.70    | 2.87    | 1.18    | 0.79    | 0.20    |
+---------+---------+---------+---------+---------+---------+---------+
| 1968    | 8.70    | 5.98    | 2.72    | 1.19    | 0.81    | 0.20    |
+---------+---------+---------+---------+---------+---------+---------+
| 1969    | 12.37   | 8.54    | 3.85    | 1.59    | 1.09    | 0.27    |
+---------+---------+---------+---------+---------+---------+---------+
| 1970    | 9.06    | 6.21    | 2.81    | 1.18    | 0.80    | 0.20    |
+---------+---------+---------+---------+---------+---------+---------+
| 1971    | 6.26    | 4.40    | 2.64    | 1.05    | 0.71    | 0.17    |
+---------+---------+---------+---------+---------+---------+---------+
| 1972    | 8.03    | 6.09    | 2.53    | 1.24    | 0.83    | 0.20    |
+---------+---------+---------+---------+---------+---------+---------+
| 1973    | 12.09   | 8.28    | 4.75    | 2.08    | 1.40    | 0.35    |
+---------+---------+---------+---------+---------+---------+---------+
| 1974    | 6.28    | 4.33    | 2.06    | 0.84    | 0.56    | 0.14    |
+---------+---------+---------+---------+---------+---------+---------+
| 1975    | 14.37   | 9.83    | 4.59    | 1.98    | 1.33    | 0.33    |
+---------+---------+---------+---------+---------+---------+---------+
| 1976    | 9.72    | 6.82    | 3.89    | 1.91    | 1.29    | 0.32    |
+---------+---------+---------+---------+---------+---------+---------+
| 1977    | 60.94   | 44.11   | 17.73   | 6.73    | 4.49    | 1.11    |
+---------+---------+---------+---------+---------+---------+---------+
| 1978    | 9.81    | 6.99    | 4.60    | 1.86    | 1.24    | 0.31    |
+---------+---------+---------+---------+---------+---------+---------+
| 1979    | 16.43   | 13.15   | 6.33    | 2.49    | 1.67    | 0.41    |
+---------+---------+---------+---------+---------+---------+---------+
| 1980    | 8.42    | 6.11    | 2.81    | 1.14    | 0.77    | 0.19    |
+---------+---------+---------+---------+---------+---------+---------+
| 1981    | 24.23   | 18.26   | 8.82    | 3.67    | 2.46    | 0.61    |
+---------+---------+---------+---------+---------+---------+---------+
| 1982    | 49.07   | 36.61   | 16.95   | 6.34    | 4.23    | 1.04    |
+---------+---------+---------+---------+---------+---------+---------+
| 1983    | 8.85    | 6.38    | 3.01    | 1.46    | 0.98    | 0.24    |
+---------+---------+---------+---------+---------+---------+---------+
| 1984    | 3.25    | 2.25    | 1.53    | 0.67    | 0.45    | 0.11    |
+---------+---------+---------+---------+---------+---------+---------+
| 1985    | 5.84    | 4.05    | 2.61    | 1.41    | 0.95    | 0.23    |
+---------+---------+---------+---------+---------+---------+---------+
| 1986    | 12.51   | 9.87    | 4.56    | 1.74    | 1.17    | 0.29    |
+---------+---------+---------+---------+---------+---------+---------+
| 1987    | 5.41    | 3.94    | 1.83    | 0.75    | 0.50    | 0.12    |
+---------+---------+---------+---------+---------+---------+---------+
| 1988    | 9.87    | 6.79    | 3.38    | 1.69    | 1.14    | 0.28    |
+---------+---------+---------+---------+---------+---------+---------+
| 1989    | 10.91   | 7.70    | 3.38    | 1.55    | 1.05    | 0.26    |
+---------+---------+---------+---------+---------+---------+---------+
| 1990    | 3.08    | 2.24    | 1.32    | 0.50    | 0.33    | 0.08    |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Sorted  |         |         |         |         |         |         |
| results |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Prob.   | Peak    | 96 hr   | 21 Day  | 60 Day  | 90 Day  | Yearly  |
+---------+---------+---------+---------+---------+---------+---------+
| 0.03    | 104.00  | 69.55   | 26.30   | 9.81    | 6.55    | 1.62    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.06    | 84.41   | 57.97   | 21.99   | 8.16    | 5.45    | 1.34    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.10    | 60.94   | 44.11   | 17.73   | 6.73    | 4.49    | 1.11    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.13    | 49.07   | 36.61   | 16.95   | 6.34    | 4.23    | 1.04    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.16    | 33.19   | 22.05   | 8.82    | 3.67    | 2.46    | 0.61    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.19    | 24.23   | 18.26   | 8.17    | 3.42    | 2.30    | 0.57    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.23    | 16.43   | 13.15   | 6.33    | 2.49    | 1.67    | 0.41    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.26    | 14.37   | 9.87    | 4.75    | 2.08    | 1.40    | 0.35    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.29    | 12.51   | 9.83    | 4.60    | 1.98    | 1.33    | 0.33    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.32    | 12.37   | 8.54    | 4.59    | 1.91    | 1.29    | 0.32    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.35    | 12.09   | 8.28    | 4.56    | 1.86    | 1.24    | 0.31    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.39    | 10.91   | 7.70    | 3.89    | 1.74    | 1.17    | 0.29    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.42    | 9.87    | 6.99    | 3.85    | 1.69    | 1.14    | 0.28    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.45    | 9.81    | 6.82    | 3.38    | 1.59    | 1.09    | 0.27    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.48    | 9.72    | 6.79    | 3.38    | 1.55    | 1.05    | 0.26    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.52    | 9.06    | 6.38    | 3.01    | 1.46    | 0.98    | 0.24    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.55    | 8.85    | 6.21    | 2.87    | 1.41    | 0.95    | 0.23    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.58    | 8.70    | 6.11    | 2.81    | 1.24    | 0.83    | 0.20    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.61    | 8.42    | 6.09    | 2.81    | 1.19    | 0.81    | 0.20    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.65    | 8.03    | 5.98    | 2.72    | 1.18    | 0.80    | 0.20    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.68    | 6.91    | 4.70    | 2.64    | 1.18    | 0.79    | 0.20    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.71    | 6.28    | 4.40    | 2.61    | 1.14    | 0.77    | 0.19    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.74    | 6.26    | 4.33    | 2.53    | 1.05    | 0.71    | 0.17    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.77    | 5.84    | 4.05    | 2.12    | 0.91    | 0.61    | 0.15    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.81    | 5.41    | 3.94    | 2.06    | 0.84    | 0.56    | 0.14    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.84    | 5.05    | 3.58    | 1.83    | 0.75    | 0.50    | 0.12    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.87    | 4.62    | 3.11    | 1.53    | 0.67    | 0.45    | 0.11    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.90    | 3.25    | 2.25    | 1.38    | 0.57    | 0.39    | 0.10    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.94    | 3.16    | 2.24    | 1.32    | 0.53    | 0.36    | 0.09    |
+---------+---------+---------+---------+---------+---------+---------+
| 0.97    | 3.08    | 2.18    | 1.15    | 0.50    | 0.33    | 0.08    |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| *       | **      | **      | **      | *       | *       | *       |
| *0.10** | 59.75** | 43.36** | 17.65** | *6.69** | *4.47** | *1.10** |
+---------+---------+---------+---------+---------+---------+---------+
| Average |         |         |         |         |         | 0.38    |
| of      |         |         |         |         |         |         |
| yearly  |         |         |         |         |         |         |
| av      |         |         |         |         |         |         |
| erages: |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Inputs  |         |         |         |         |         |         |
| ge      |         |         |         |         |         |         |
| nerated |         |         |         |         |         |         |
| by      |         |         |         |         |         |         |
| p       |         |         |         |         |         |         |
| e4.pl - |         |         |         |         |         |         |
| 8-Augu  |         |         |         |         |         |         |
| st-2003 |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| Data    |         |         |         |         |         |         |
| used    |         |         |         |         |         |         |
| for     |         |         |         |         |         |         |
| this    |         |         |         |         |         |         |
| run:    |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| Output  |         |         |         |         |         |         |
| File:   |         |         |         |         |         |         |
| F       |         |         |         |         |         |         |
| LStrawb |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| M       |         |         |         |         |         |         |
| etfile: |         |         |         |         |         |         |
| w12     |         |         |         |         |         |         |
| 842.dvf |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| PRZM    |         |         |         |         |         |         |
| sc      |         |         |         |         |         |         |
| enario: |         |         |         |         |         |         |
| FLs     |         |         |         |         |         |         |
| trawber |         |         |         |         |         |         |
| ryC.txt |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| EXAMS   |         |         |         |         |         |         |
| envi    |         |         |         |         |         |         |
| ronment |         |         |         |         |         |         |
| file:   |         |         |         |         |         |         |
| pond    |         |         |         |         |         |         |
| 298.exv |         |         |         |         |         |         |
|         |         |         |         |         |         |         |
| C       |         |         |         |         |         |         |
| hemical |         |         |         |         |         |         |
| Name:   |         |         |         |         |         |         |
| Chlor   |         |         |         |         |         |         |
| opicrin |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Desc    | V       | Value   | Units   | C       |         |         |
| ription | ariable |         |         | omments |         |         |
|         | Name    |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Mo      | mwt     | 164.4   | g/mol   |         |         |         |
| lecular |         |         |         |         |         |         |
| weight  |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| H       | henry   | 0.00205 | atm-m   |         |         |         |
| enry\'s |         |         | \^3/mol |         |         |         |
| Law     |         |         |         |         |         |         |
| Const.  |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Vapor   | vapr    | 23.8    | torr    |         |         |         |
| P       |         |         |         |         |         |         |
| ressure |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Sol     | sol     | 1621    | mg/L    |         |         |         |
| ubility |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Kd      | Kd      |         | mg/L    |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Koc     | Koc     | 36.05   | mg/L    |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Pho     | kdp     | 1.3     | days    | Ha      |         |         |
| tolysis |         |         |         | lf-life |         |         |
| ha      |         |         |         |         |         |         |
| lf-life |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Aerobic | kbacw   | 31.42   | days    | Halfife |         |         |
| Aquatic |         |         |         |         |         |         |
| Met     |         |         |         |         |         |         |
| abolism |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| An      | kbacs   | 0.05    | days    | Halfife |         |         |
| aerobic |         |         |         |         |         |         |
| Aquatic |         |         |         |         |         |         |
| Met     |         |         |         |         |         |         |
| abolism |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Aerobic | asm     | 15.71   | days    | Halfife |         |         |
| Soil    |         |         |         |         |         |         |
| Met     |         |         |         |         |         |         |
| abolism |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Hydr    | pH 7    | 0       | days    | Ha      |         |         |
| olysis: |         |         |         | lf-life |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Method: | CAM     | 8       | integer | See     |         |         |
|         |         |         |         | PRZM    |         |         |
|         |         |         |         | manual  |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Incorp  | DEPI    | 25      | cm      |         |         |         |
| oration |         |         |         |         |         |         |
| Depth:  |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Appl    | TAPP    | 392     | kg/ha   |         |         |         |
| ication |         |         |         |         |         |         |
| Rate:   |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Appl    | APPEFF  | 1       | f       |         |         |         |
| ication |         |         | raction |         |         |         |
| Effi    |         |         |         |         |         |         |
| ciency: |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Spray   | DRFT    | 0       | f       |         |         |         |
| Drift   |         |         | raction |         |         |         |
|         |         |         | of      |         |         |         |
|         |         |         | appl    |         |         |         |
|         |         |         | ication |         |         |         |
|         |         |         | rate    |         |         |         |
|         |         |         | applied |         |         |         |
|         |         |         | to pond |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Appl    | Date    | 15-9    | dd/mm   |         |         |         |
| ication |         |         | or      |         |         |         |
| Date    |         |         | dd/mmm  |         |         |         |
|         |         |         | or      |         |         |         |
|         |         |         | dd-mm   |         |         |         |
|         |         |         | or      |         |         |         |
|         |         |         | dd-mmm  |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Record  | FILTRA  |         |         |         |         |         |
| 17:     |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         | IPSCND  | 1       |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         | UPTKF   |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Record  | PLVKRT  |         |         |         |         |         |
| 18:     |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         | PLDKRT  |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         | FEXTRC  | 0       |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Flag    | IR      | Pond    |         |         |         |         |
| for     |         |         |         |         |         |         |
| Index   |         |         |         |         |         |         |
| Res.    |         |         |         |         |         |         |
| Run     |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
| Flag    | RUNOFF  | none    | none,   |         |         |         |
| for     |         |         | monthly |         |         |         |
| runoff  |         |         | or      |         |         |         |
| calc.   |         |         | total(  |         |         |         |
|         |         |         | average |         |         |         |
|         |         |         | of      |         |         |         |
|         |         |         | entire  |         |         |         |
|         |         |         | run)    |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+
|         |         |         |         |         |         |         |
+---------+---------+---------+---------+---------+---------+---------+

**B.1.2 Florida Tomato**

  ---------------- ------------ ----------- --------------- ----------- ----------- ----------
  stored as                                                                         
  FLTomato.out                                                                      

  Chemical:                                                                         
  Chloropicrin                                                                      

  PRZM                                                                              
  environment:                                                                      
  FltomatoC.txt,                                                                    
  Mmodified                                                                         
  Satday, 12                                                                        
  October 2002 at                                                                   
  16:44:04                                                                          

  EXAMS                                                                             
  environment:                                                                      
  pond298.exv,                                                                      
  Mmodified                                                                         
  Thuday, 29                                                                        
  August 2002 at                                                                    
  16:33:30                                                                          

  Metfile:                                                                          
  w12844.dvf,                                                                       
  Modified Wedday,                                                                  
  3 July 2002 at                                                                    
  09:04:30                                                                          

                                                                                    

  **Water segment                                                                   
  concentrations                                                                    
  (ppb)**                                                                           

  Year             Peak         96 hr       21 Day          60 Day      90 Day      Yearly

  1961             1.97         1.31        0.69            0.45        0.30        0.07

  1962             106.00       79.75       29.59           10.54       7.03        1.73

  1963             77.19        53.35       30.82           12.70       8.47        2.09

  1964             56.35        38.79       19.41           7.97        5.33        1.31

  1965             20.89        15.09       6.21            3.20        2.15        0.53

  1966             24.46        17.68       7.92            3.41        2.27        0.56

  1967             69.80        48.03       20.98           8.44        5.63        1.39

  1968             55.26        44.23       24.24           9.56        6.37        1.57

  1969             55.05        37.46       18.79           7.41        4.95        1.22

  1970             31.83        21.15       9.60            3.46        2.31        0.57

  1971             4.84         3.30        1.22            0.73        0.49        0.12

  1972             1.49         1.03        0.36            0.13        0.09        0.02

  1973             10.10        6.95        3.58            1.92        1.28        0.32

  1974             21.65        12.56       6.02            2.28        1.53        0.38

  1975             134.00       91.32       35.73           12.86       8.58        2.11

  1976             4.26         2.83        1.16            0.69        0.47        0.11

  1977             29.54        20.72       7.30            2.61        1.76        0.43

  1978             12.72        8.86        3.67            1.58        1.06        0.26

  1979             30.37        22.90       10.76           4.22        2.82        0.69

  1980             13.06        8.86        2.94            1.29        0.87        0.21

  1981             57.10        43.42       14.60           5.39        3.61        0.89

  1982             20.74        14.47       6.84            2.64        1.76        0.43

  1983             108.00       72.53       27.05           10.10       6.75        1.66

  1984             64.45        46.78       21.74           7.87        5.29        1.30

  1985             78.82        55.70       24.52           8.96        5.98        1.47

  1986             4.07         2.68        0.84            0.55        0.38        0.10

  1987             71.64        48.12       20.39           7.73        5.16        1.27

  1988             4.06         2.68        0.85            0.32        0.21        0.05

  1989             42.45        27.53       9.17            3.63        2.42        0.60

  1990             198.00       132.00      46.46           16.59       11.06       2.73

                                                                                    

  Sorted results                                                                    

  Prob.            Peak         96 hr       21 Day          60 Day      90 Day      Yearly

  0.03             198.00       132.00      46.46           16.59       11.06       2.73

  0.06             134.00       91.32       35.73           12.86       8.58        2.11

  0.10             108.00       79.75       30.82           12.70       8.47        2.09

  0.13             106.00       72.53       29.59           10.54       7.03        1.73

  0.16             78.82        55.70       27.05           10.10       6.75        1.66

  0.19             77.19        53.35       24.52           9.56        6.37        1.57

  0.23             71.64        48.12       24.24           8.96        5.98        1.47

  0.26             69.80        48.03       21.74           8.44        5.63        1.39

  0.29             64.45        46.78       20.98           7.97        5.33        1.31

  0.32             57.10        44.23       20.39           7.87        5.29        1.30

  0.35             56.35        43.42       19.41           7.73        5.16        1.27

  0.39             55.26        38.79       18.79           7.41        4.95        1.22

  0.42             55.05        37.46       14.60           5.39        3.61        0.89

  0.45             42.45        27.53       10.76           4.22        2.82        0.69

  0.48             31.83        22.90       9.60            3.63        2.42        0.60

  0.52             30.37        21.15       9.17            3.46        2.31        0.57

  0.55             29.54        20.72       7.92            3.41        2.27        0.56

  0.58             24.46        17.68       7.30            3.20        2.15        0.53

  0.61             21.65        15.09       6.84            2.64        1.76        0.43

  0.65             20.89        14.47       6.21            2.61        1.76        0.43

  0.68             20.74        12.56       6.02            2.28        1.53        0.38

  0.71             13.06        8.86        3.67            1.92        1.28        0.32

  0.74             12.72        8.86        3.58            1.58        1.06        0.26

  0.77             10.10        6.95        2.94            1.29        0.87        0.21

  0.81             4.84         3.30        1.22            0.73        0.49        0.12

  0.84             4.26         2.83        1.16            0.69        0.47        0.11

  0.87             4.07         2.68        0.85            0.55        0.38        0.10

  0.90             4.06         2.68        0.84            0.45        0.30        0.07

  0.94             1.97         1.31        0.69            0.32        0.21        0.05

  0.97             1.49         1.03        0.36            0.13        0.09        0.02

                                                                                    

  **0.10**         **107.80**   **79.03**   **30.70**       **12.48**   **8.33**    **2.05**

                                                                        Average of  0.87
                                                                        yearly      
                                                                        averages:   

                                                                                    

  Inputs generated                                                                  
  by pe4.pl -                                                                       
  8-August-2003                                                                     

                                                                                    

  Data used for                                                                     
  this run:                                                                         

  Output File:                                                                      
  FLTomato                                                                          

  Metfile:                                                                          
  w12844.dvf                                                                        

  PRZM scenario:                                                                    
  FLtomatoC.txt                                                                     

  EXAMS                                                                             
  environment                                                                       
  file:                                                                             
  pond298.exv                                                                       

  Chemical Name:                                                                    
  Chloropicrin                                                                      

  Description      Variable     Value       Units           Comments                
                   Name                                                             

  Molecular weight mwt          164.4       g/mol                                   

  Henry\'s Law     henry        0.00205     atm-m\^3/mol                            
  Const.                                                                            

  Vapor Pressure   vapr         23.8        torr                                    

  Solubility       sol          1621        mg/L                                    

  Kd               Kd                       mg/L                                    

  Koc              Koc          36.05       mg/L                                    

  Photolysis       kdp          1.3         days            Half-life               
  half-life                                                                         

  Aerobic Aquatic  kbacw        31.42       days            Halfife                 
  Metabolism                                                                        

  Anaerobic        kbacs        0.05        days            Halfife                 
  Aquatic                                                                           
  Metabolism                                                                        

  Aerobic Soil     asm          15.71       days            Halfife                 
  Metabolism                                                                        

  Hydrolysis:      pH 7         0           days            Half-life               

  Method:          CAM          8           integer         See PRZM                
                                                            manual                  

  Incorporation    DEPI         25          cm                                      
  Depth:                                                                            

  Application      TAPP         392         kg/ha                                   
  Rate:                                                                             

  Application      APPEFF       1           fraction                                
  Efficiency:                                                                       

  Spray Drift      DRFT         0           fraction of                             
                                            application                             
                                            rate applied to                         
                                            pond                                    

  Application Date Date         15-9        dd/mm or dd/mmm                         
                                            or dd-mm or                             
                                            dd-mmm                                  

  Record 17:       FILTRA                                                           

                   IPSCND       1                                                   

                   UPTKF                                                            

  Record 18:       PLVKRT                                                           

                   PLDKRT                                                           

                   FEXTRC       0                                                   

  Flag for Index   IR           Pond                                                
  Res. Run                                                                          

  Flag for runoff  RUNOFF       none        none, monthly                           
  calc.                                     or                                      
                                            total(average                           
                                            of entire run)                          
  ---------------- ------------ ----------- --------------- ----------- ----------- ----------

**B.2.1 California Tomato**

  ---------------- ---------- ---------- --------------- ----------- ----------- ----------
  stored as                                                                      
  CATomato.out                                                                   

  Chemical:                                                                      
  Chloropicrin                                                                   

  PRZM                                                                           
  environment:                                                                   
  CAtomatoC.txt                                                                  
  Modified Wedday,                                                               
  2 February 2005                                                                
  at 12:45:10                                                                    

  EXAMS                                                                          
  environment:                                                                   
  pond298.exv,                                                                   
  Modified Thuday,                                                               
  29 August 2002                                                                 
  at 16:33:30                                                                    

  Metfile:                                                                       
  w93193.dvf,                                                                    
  Modified Wedday,                                                               
  3 July 2002 at                                                                 
  09:04:24                                                                       

                                                                                 

  **Water segment                                                                
  concentrations                                                                 
  (ppb)**                                                                        

  Year             Peak       96 hr      21 Day          60 Day      90 Day      Yearly

  1961             0.28       0.23       0.15            0.06        0.04        0.01

  1962             0.44       0.34       0.15            0.05        0.04        0.01

  1963             1.77       1.43       0.77            0.40        0.28        0.07

  1964             2.50       1.90       0.91            0.36        0.24        0.06

  1965             0.11       0.09       0.05            0.02        0.02        0.01

  1966             0.52       0.46       0.27            0.13        0.09        0.02

  1967             0.24       0.19       0.10            0.04        0.03        0.01

  1968             2.23       1.75       0.85            0.49        0.34        0.09

  1969             0.17       0.15       0.08            0.03        0.02        0.01

  1970             0.28       0.22       0.13            0.06        0.04        0.01

  1971             0.12       0.10       0.04            0.02        0.01        0.00

  1972             0.50       0.42       0.26            0.11        0.07        0.02

  1973             1.73       1.35       0.60            0.25        0.18        0.04

  1974             6.62       5.11       2.42            1.00        0.67        0.17

  1975             1.31       1.03       0.52            0.21        0.14        0.04

  1976             4.19       3.30       1.48            0.63        0.43        0.11

  1977             0.72       0.58       0.25            0.09        0.06        0.02

  1978             0.25       0.21       0.10            0.05        0.03        0.01

  1979             0.35       0.29       0.14            0.06        0.04        0.01

  1980             0.02       0.02       0.01            0.00        0.00        0.00

  1981             0.20       0.15       0.08            0.04        0.02        0.01

  1982             3.79       2.93       1.87            0.84        0.61        0.16

  1983             0.80       0.58       0.25            0.17        0.13        0.03

  1984             0.68       0.54       0.27            0.16        0.13        0.03

  1985             0.66       0.52       0.26            0.18        0.12        0.03

  1986             0.14       0.12       0.05            0.02        0.01        0.01

  1987             0.21       0.16       0.08            0.05        0.03        0.01

  1988             0.13       0.11       0.06            0.03        0.02        0.01

  1989             0.14       0.10       0.04            0.01        0.01        0.00

  1990             0.07       0.05       0.03            0.02        0.01        0.00

                                                                                 

  Sorted results                                                                 

  Prob.            Peak       96 hr      21 Day          60 Day      90 Day      Yearly

  0.03             6.62       5.11       2.42            1.00        0.67        0.17

  0.06             4.19       3.30       1.87            0.84        0.61        0.16

  0.10             3.79       2.93       1.48            0.63        0.43        0.11

  0.13             2.50       1.90       0.91            0.49        0.34        0.09

  0.16             2.23       1.75       0.85            0.40        0.28        0.07

  0.19             1.77       1.43       0.77            0.36        0.24        0.06

  0.23             1.73       1.35       0.60            0.25        0.18        0.04

  0.26             1.31       1.03       0.52            0.21        0.14        0.04

  0.29             0.80       0.58       0.27            0.18        0.13        0.03

  0.32             0.72       0.58       0.27            0.17        0.13        0.03

  0.35             0.68       0.54       0.26            0.16        0.12        0.03

  0.39             0.66       0.52       0.26            0.13        0.09        0.02

  0.42             0.52       0.46       0.25            0.11        0.07        0.02

  0.45             0.50       0.42       0.25            0.09        0.06        0.02

  0.48             0.44       0.34       0.15            0.06        0.04        0.01

  0.52             0.35       0.29       0.15            0.06        0.04        0.01

  0.55             0.28       0.23       0.14            0.06        0.04        0.01

  0.58             0.28       0.22       0.13            0.05        0.04        0.01

  0.61             0.25       0.21       0.10            0.05        0.03        0.01

  0.65             0.24       0.19       0.10            0.05        0.03        0.01

  0.68             0.21       0.16       0.08            0.04        0.03        0.01

  0.71             0.20       0.15       0.08            0.04        0.02        0.01

  0.74             0.17       0.15       0.08            0.03        0.02        0.01

  0.77             0.14       0.12       0.06            0.03        0.02        0.01

  0.81             0.14       0.11       0.05            0.02        0.02        0.01

  0.84             0.13       0.10       0.05            0.02        0.01        0.01

  0.87             0.12       0.10       0.04            0.02        0.01        0.00

  0.90             0.11       0.09       0.04            0.02        0.01        0.00

  0.94             0.07       0.05       0.03            0.01        0.01        0.00

  0.97             0.02       0.02       0.01            0.00        0.00        0.00

                                                                                 

  **0.10**         **3.66**   **2.83**   **1.42**        **0.61**    **0.42**    **0.10**

                                                                     Average of  0.03
                                                                     yearly      
                                                                     averages:   

                                                                                 

  Inputs generated                                                               
  by pe4.pl -                                                                    
  8-August-2003                                                                  

                                                                                 

  Data used for                                                                  
  this run:                                                                      

  Output File:                                                                   
  CATomato                                                                       

  Metfile:                                                                       
  w93193.dvf                                                                     

  PRZM scenario:                                                                 
  CAtomatoC.txt                                                                  

  EXAMS                                                                          
  environment                                                                    
  file:                                                                          
  pond298.exv                                                                    

  Chemical Name:                                                                 
  Chloropicrin                                                                   

  Description      Variable   Value      Units           Comments                
                   Name                                                          

  Molecular weight mwt        164.4      g/mol                                   

  Henry\'s Law     henry      0.00205    atm-m\^3/mol                            
  Const.                                                                         

  Vapor Pressure   vapr       23.8       torr                                    

  Solubility       sol        1621       mg/L                                    

  Kd               Kd                    mg/L                                    

  Koc              Koc        36.05      mg/L                                    

  Photolysis       kdp        1.3        days            Half-life               
  half-life                                                                      

  Aerobic Aquatic  kbacw      31.42      days            Halfife                 
  Metabolism                                                                     

  Anaerobic        kbacs      0.05       days            Halfife                 
  Aquatic                                                                        
  Metabolism                                                                     

  Aerobic Soil     asm        15.71      days            Halfife                 
  Metabolism                                                                     

  Hydrolysis:      pH 7       0          days            Half-life               

  Method:          CAM        8          integer         See PRZM                
                                                         manual                  

  Incorporation    DEPI       25         cm                                      
  Depth:                                                                         

  Application      TAPP       392        kg/ha                                   
  Rate:                                                                          

  Application      APPEFF     1          fraction                                
  Efficiency:                                                                    

  Spray Drift      DRFT       0          fraction of                             
                                         application                             
                                         rate applied to                         
                                         pond                                    

  Application Date Date       15-9       dd/mm or dd/mmm                         
                                         or dd-mm or                             
                                         dd-mmm                                  

  Record 17:       FILTRA                                                        

                   IPSCND     1                                                  

                   UPTKF                                                         

  Record 18:       PLVKRT                                                        

                   PLDKRT                                                        

                   FEXTRC     0                                                  

  Flag for Index   IR         Pond                                               
  Res. Run                                                                       

  Flag for runoff  RUNOFF     none       none, monthly                           
  calc.                                  or                                      
                                         total(average                           
                                         of entire run)                          
  ---------------- ---------- ---------- --------------- ----------- ----------- ----------

**B.2.2 California Onion**

  ---------------- -------------- ---------- --------------- ----------- ---------- ----------
  stored as                                                                         
  CAOnion.out                                                                       

  Chemical:                                                                         
  Chloropicrin                                                                      

  PRZM                                                                              
  environment:                                                                      
  CAonionC.txt                                                                      
  Modified Monday,                                                                  
  23 December 2002                                                                  
  at 06:48:48                                                                       

  EXAMS                                                                             
  environment:                                                                      
  pond298.exv,                                                                      
  Modified Thuday,                                                                  
  29 August 2002                                                                    
  at 16:33:30                                                                       

  Metfile:                                                                          
  w23155.dvf,                                                                       
  Modified Wedday,                                                                  
  3 July 2002 at                                                                    
  09:04:20                                                                          

                                                                                    

  **Water segment                                                                   
  concentrations                                                                    
  (ppb)**                                                                           

  Year             Peak           96 hr      21 Day          60 Day      90 Day     Yearly

  1961             0.02           0.02       0.01            0.00        0.00       0.00

  1962             0.00           0.00       0.00            0.00        0.00       0.00

  1963             15.87          11.74      4.63            1.73        1.15       0.28

  1964             0.19           0.14       0.06            0.02        0.02       0.00

  1965             0.06           0.05       0.02            0.01        0.01       0.00

  1966             0.06           0.05       0.03            0.02        0.01       0.00

  1967             0.10           0.09       0.05            0.02        0.02       0.00

  1968             0.49           0.39       0.19            0.08        0.06       0.01

  1969             0.04           0.03       0.01            0.00        0.00       0.00

  1970             0.06           0.04       0.02            0.01        0.01       0.00

  1971             0.01           0.00       0.00            0.00        0.00       0.00

  1972             0.29           0.23       0.10            0.06        0.04       0.01

  1973             0.01           0.01       0.01            0.00        0.00       0.00

  1974             5.68           4.26       1.70            0.65        0.44       0.11

  1975             0.01           0.00       0.00            0.00        0.00       0.00

  1976             0.50           0.35       0.13            0.05        0.03       0.01

  1977             0.03           0.02       0.00            0.00        0.00       0.00

  1978             0.02           0.01       0.01            0.00        0.00       0.00

  1979             0.00           0.00       0.00            0.00        0.00       0.00

  1980             0.00           0.00       0.00            0.00        0.00       0.00

  1981             1.94           1.48       0.61            0.23        0.15       0.04

  1982             2.16           1.56       0.60            0.24        0.17       0.04

  1983             0.09           0.07       0.03            0.02        0.01       0.00

  1984             0.06           0.04       0.02            0.01        0.01       0.00

  1985             0.35           0.28       0.13            0.06        0.04       0.01

  1986             0.03           0.02       0.01            0.01        0.00       0.00

  1987             1.44           1.15       0.53            0.20        0.14       0.03

  1988             0.00           0.00       0.00            0.00        0.00       0.00

  1989             1.09           0.68       0.20            0.07        0.05       0.01

  1990             0.00           0.00       0.00            0.00        0.00       0.00

                                                                                    

  Sorted results                                                                    

  Prob.            Peak           96 hr      21 Day          60 Day      90 Day     Yearly

  0.03             15.87          11.74      4.63            1.73        1.15       0.28

  0.06             5.68           4.26       1.70            0.65        0.44       0.11

  0.10             2.16           1.56       0.61            0.24        0.17       0.04

  0.13             1.94           1.48       0.60            0.23        0.15       0.04

  0.16             1.44           1.15       0.53            0.20        0.14       0.03

  0.19             1.09           0.68       0.20            0.08        0.06       0.01

  0.23             0.50           0.39       0.19            0.07        0.05       0.01

  0.26             0.49           0.35       0.13            0.06        0.04       0.01

  0.29             0.35           0.28       0.13            0.06        0.04       0.01

  0.32             0.29           0.23       0.10            0.05        0.03       0.01

  0.35             0.19           0.14       0.06            0.02        0.02       0.00

  0.39             0.10           0.09       0.05            0.02        0.02       0.00

  0.42             0.09           0.07       0.03            0.02        0.01       0.00

  0.45             0.06           0.05       0.03            0.02        0.01       0.00

  0.48             0.06           0.05       0.02            0.01        0.01       0.00

  0.52             0.06           0.04       0.02            0.01        0.01       0.00

  0.55             0.06           0.04       0.02            0.01        0.01       0.00

  0.58             0.04           0.03       0.01            0.01        0.00       0.00

  0.61             0.03           0.02       0.01            0.00        0.00       0.00

  0.65             0.03           0.02       0.01            0.00        0.00       0.00

  0.68             0.02           0.02       0.01            0.00        0.00       0.00

  0.71             0.02           0.01       0.01            0.00        0.00       0.00

  0.74             0.01           0.01       0.00            0.00        0.00       0.00

  0.77             0.01           0.00       0.00            0.00        0.00       0.00

  0.81             0.01           0.00       0.00            0.00        0.00       0.00

  0.84             0.00           0.00       0.00            0.00        0.00       0.00

  0.87             0.00           0.00       0.00            0.00        0.00       0.00

  0.90             0.00           0.00       0.00            0.00        0.00       0.00

  0.94             0.00           0.00       0.00            0.00        0.00       0.00

  0.97             0.00           0.00       0.00            0.00        0.00       0.00

                                                                                    

  **0.10**         **2.14**       **1.55**   **0.61**        **0.24**    **0.17**   **0.04**

  Average of                                                                        0.02
  yearly averages:                                                                  

                                                                                    

  Inputs generated                                                                  
  by pe4.pl -                                                                       
  8-August-2003                                                                     

                                                                                    

  Data used for                                                                     
  this run:                                                                         

  Output File:                                                                      
  CAOnion                                                                           

  Metfile:                                                                          
  w23155.dvf                                                                        

  PRZM scenario:                                                                    
  CAonionC.txt                                                                      

  EXAMS                                                                             
  environment                                                                       
  file:                                                                             
  pond298.exv                                                                       

  Chemical Name:   Chloropicrin                                                     

  Description      Variable Name  Value      Units           Comments               

  Molecular weight mwt            164.4      g/mol                                  

  Henry\'s Law     henry          0.00205    atm-m\^3/mol                           
  Const.                                                                            

  Vapor Pressure   vapr           23.8       torr                                   

  Solubility       sol            1621       mg/L                                   

  Kd               Kd                        mg/L                                   

  Koc              Koc            36.05      mg/L                                   

  Photolysis       kdp            1.3        days            Half-life              
  half-life                                                                         

  Aerobic Aquatic  kbacw          31.42      days            Halfife                
  Metabolism                                                                        

  Anaerobic        kbacs          0.05       days            Halfife                
  Aquatic                                                                           
  Metabolism                                                                        

  Aerobic Soil     asm            15.71      days            Halfife                
  Metabolism                                                                        

  Hydrolysis:      pH 7           0          days            Half-life              

  Method:          CAM            8          integer         See PRZM               
                                                             manual                 

  Incorporation    DEPI           25         cm                                     
  Depth:                                                                            

  Application      TAPP           392        kg/ha                                  
  Rate:                                                                             

  Application      APPEFF         1          fraction                               
  Efficiency:                                                                       

  Spray Drift      DRFT           0          fraction of                            
                                             application                            
                                             rate applied to                        
                                             pond                                   

  Application Date Date           15-9       dd/mm or dd/mmm                        
                                             or dd-mm or                            
                                             dd-mmm                                 

  Record 17:       FILTRA                                                           

                   IPSCND         1                                                 

                   UPTKF                                                            

  Record 18:       PLVKRT                                                           

                   PLDKRT                                                           

                   FEXTRC         0                                                 

  Flag for Index   IR             Pond                                              
  Res. Run                                                                          

  Flag for runoff  RUNOFF         none       none, monthly                          
  calc.                                      or                                     
                                             total(average                          
                                             of entire run)                         
  ---------------- -------------- ---------- --------------- ----------- ---------- ----------

**B.3.1 North Carolina Tobacco**

  --------------------- -------------- ---------- --------------- ----------- ---------- ----------
  stored as NCTobac.out                                                                  

  Chemical:                                                                              
  Chloropicrin                                                                           

  PRZM environment:                                                                      
  NctobaccoC.txt,                                                                        
  modified Satday, 12                                                                    
  October 2002 at                                                                        
  17:13:36                                                                               

  EXAMS environment:                                                                     
  pond298.exv, modified                                                                  
  Thuday, 29 August                                                                      
  2002 at 16:33:30                                                                       

  Metfile:                                                                               
  w13722.dvf,modified                                                                    
  Wedday, 3 July 2002                                                                    
  at 09:05:50                                                                            

                                                                                         

  **Water segment                                                                        
  concentrations                                                                         
  (ppb)**                                                                                

  Year                  Peak           96 hr      21 Day          60 Day      90 Day     Yearly

  1961                  0.67           0.49       0.18            0.07        0.04       0.01

  1962                  0.03           0.02       0.01            0.01        0.00       0.00

  1963                  0.61           0.46       0.21            0.08        0.05       0.01

  1964                  0.02           0.01       0.00            0.00        0.00       0.00

  1965                  0.14           0.11       0.04            0.02        0.01       0.00

  1966                  0.91           0.67       0.26            0.11        0.07       0.02

  1967                  0.97           0.70       0.41            0.17        0.12       0.03

  1968                  0.08           0.06       0.02            0.01        0.01       0.00

  1969                  0.07           0.05       0.03            0.01        0.01       0.00

  1970                  0.29           0.21       0.08            0.03        0.02       0.00

  1971                  0.25           0.18       0.08            0.04        0.02       0.01

  1972                  0.55           0.40       0.22            0.08        0.06       0.01

  1973                  1.68           1.26       0.48            0.18        0.12       0.03

  1974                  0.29           0.22       0.12            0.05        0.04       0.01

  1975                  0.07           0.06       0.02            0.01        0.01       0.00

  1976                  0.19           0.14       0.06            0.02        0.02       0.00

  1977                  0.07           0.05       0.02            0.01        0.01       0.00

  1978                  2.70           2.01       0.85            0.31        0.21       0.05

  1979                  0.08           0.06       0.04            0.03        0.02       0.00

  1980                  0.44           0.33       0.13            0.05        0.03       0.01

  1981                  0.19           0.14       0.06            0.02        0.01       0.00

  1982                  0.80           0.60       0.24            0.10        0.07       0.02

  1983                  0.05           0.04       0.02            0.01        0.01       0.00

  1984                  0.77           0.64       0.27            0.11        0.08       0.02

  1985                  1.26           0.93       0.36            0.14        0.09       0.02

  1986                  0.09           0.07       0.03            0.01        0.01       0.00

  1987                  0.01           0.01       0.00            0.00        0.00       0.00

  1988                  1.69           1.27       0.50            0.20        0.13       0.03

  1989                  1.67           1.22       0.47            0.17        0.12       0.03

  1990                  0.60           0.43       0.18            0.07        0.05       0.01

                                                                                         

  Sorted results                                                                         

  Prob.                 Peak           96 hr      21 Day          60 Day      90 Day     Yearly

  0.03                  2.70           2.01       0.85            0.31        0.21       0.05

  0.06                  1.69           1.27       0.50            0.20        0.13       0.03

  0.10                  1.68           1.26       0.48            0.18        0.12       0.03

  0.13                  1.67           1.22       0.47            0.17        0.12       0.03

  0.16                  1.26           0.93       0.41            0.17        0.12       0.03

  0.19                  0.97           0.70       0.36            0.14        0.09       0.02

  0.23                  0.91           0.67       0.27            0.11        0.08       0.02

  0.26                  0.80           0.64       0.26            0.11        0.07       0.02

  0.29                  0.77           0.60       0.24            0.10        0.07       0.02

  0.32                  0.67           0.49       0.22            0.08        0.06       0.01

  0.35                  0.61           0.46       0.21            0.08        0.05       0.01

  0.39                  0.60           0.43       0.18            0.07        0.05       0.01

  0.42                  0.55           0.40       0.18            0.07        0.04       0.01

  0.45                  0.44           0.33       0.13            0.05        0.04       0.01

  0.48                  0.29           0.22       0.12            0.05        0.03       0.01

  0.52                  0.29           0.21       0.08            0.04        0.02       0.01

  0.55                  0.25           0.18       0.08            0.03        0.02       0.00

  0.58                  0.19           0.14       0.06            0.03        0.02       0.00

  0.61                  0.19           0.14       0.06            0.02        0.02       0.00

  0.65                  0.14           0.11       0.04            0.02        0.01       0.00

  0.68                  0.09           0.07       0.04            0.02        0.01       0.00

  0.71                  0.08           0.06       0.03            0.01        0.01       0.00

  0.74                  0.08           0.06       0.03            0.01        0.01       0.00

  0.77                  0.07           0.06       0.02            0.01        0.01       0.00

  0.81                  0.07           0.05       0.02            0.01        0.01       0.00

  0.84                  0.07           0.05       0.02            0.01        0.01       0.00

  0.87                  0.05           0.04       0.02            0.01        0.01       0.00

  0.90                  0.03           0.02       0.01            0.01        0.00       0.00

  0.94                  0.02           0.01       0.00            0.00        0.00       0.00

  0.97                  0.01           0.01       0.00            0.00        0.00       0.00

                                                                                         

  **0.10**              **1.67**       **1.26**   **0.48**        **0.18**    **0.12**   **0.03**

  Average of yearly                                                                      0.01
  averages:                                                                              

  Inputs generated by                                                                    
  pe4.pl -                                                                               
  8-August-2003                                                                          

  Data used for this                                                                     
  run:                                                                                   

  Output File: NCTobac                                                                   

  Metfile: w13722.dvf                                                                    

  PRZM scenario:                                                                         
  NCtobaccoC.txt                                                                         

  EXAMS environment     pond298.exv                                                      
  file:                                                                                  

  Chemical Name:        Chloropicrin                                                     

  Description           Variable Name  Value      Units           Comments               

  Molecular weight      mwt            164.4      g/mol                                  

  Henry\'s Law Const.   henry          0.00205    atm-m\^3/mol                           

  Vapor Pressure        vapr           23.8       torr                                   

  Solubility            sol            1621       mg/L                                   

  Kd                    Kd                        mg/L                                   

  Koc                   Koc            36.05      mg/L                                   

  Photolysis half-life  kdp            1.3        days            Half-life              

  Aerobic Aquatic       kbacw          31.42      days            Halfife                
  Metabolism                                                                             

  Anaerobic Aquatic     kbacs          0.05       days            Halfife                
  Metabolism                                                                             

  Aerobic Soil          asm            15.71      days            Halfife                
  Metabolism                                                                             

  Hydrolysis:           pH 7           0          days            Half-life              

  Method:               CAM            8          integer         See PRZM               
                                                                  manual                 

  Incorporation Depth:  DEPI           25         cm                                     

  Application Rate:     TAPP           392        kg/ha                                  

  Application           APPEFF         1          fraction                               
  Efficiency:                                                                            

  Spray Drift           DRFT           0          fraction of                            
                                                  application                            
                                                  rate applied to                        
                                                  pond                                   

  Application Date      Date           15-4       dd/mm or dd/mmm                        
                                                  or dd-mm or                            
                                                  dd-mmm                                 

  Record 17:            FILTRA                                                           

                        IPSCND         1                                                 

                        UPTKF                                                            

  Record 18:            PLVKRT                                                           

                        PLDKRT                                                           

                        FEXTRC         0                                                 

  Flag for Index Res.   IR             Pond                                              
  Run                                                                                    

  Flag for runoff calc. RUNOFF         none       none, monthly                          
                                                  or                                     
                                                  total(average                          
                                                  of entire run)                         
  --------------------- -------------- ---------- --------------- ----------- ---------- ----------

**B.3.2 North Carolina Sweet Potato**

  ----------------------------- -------------------- ---------- --------------- ----------- ---------- ----------
  stored as NCsweet.out                                                                                

  Chemical: Chloropicrin                                                                               

  PRZM environment:                                                                                    
  NCSweetPotatoC.txt,modified                                                                          
  Friday, 8 August 2003 at                                                                             
  09:25:48                                                                                             

  EXAMS environment:                                                                                   
  pond298.exv, modified Thuday,                                                                        
  29 August 2002 at 16:33:30                                                                           

  Metfile: w13722.dvf, modified                                                                        
  Wedday, 3 July 2002 at                                                                               
  09:05:50                                                                                             

  Water segment concentrations                                                                         
  (ppb)                                                                                                

                                                                                                       

  Year                          Peak                 96 hr      21 Day          60 Day      90 Day     Yearly

  1961                          1.21                 0.96       0.37            0.14        0.09       0.02

  1962                          0.13                 0.10       0.06            0.05        0.03       0.01

  1963                          0.97                 0.73       0.36            0.14        0.10       0.02

  1964                          0.12                 0.09       0.03            0.02        0.02       0.00

  1965                          0.32                 0.23       0.12            0.06        0.05       0.01

  1966                          0.99                 0.76       0.36            0.17        0.12       0.03

  1967                          0.51                 0.36       0.15            0.11        0.09       0.02

  1968                          0.29                 0.21       0.08            0.04        0.03       0.01

  1969                          0.21                 0.16       0.09            0.04        0.04       0.01

  1970                          0.53                 0.37       0.15            0.05        0.05       0.01

  1971                          0.33                 0.26       0.13            0.06        0.05       0.01

  1972                          0.84                 0.61       0.30            0.13        0.10       0.03

  1973                          1.77                 1.34       0.51            0.21        0.15       0.04

  1974                          0.97                 0.71       0.34            0.15        0.10       0.03

  1975                          0.29                 0.23       0.11            0.06        0.05       0.01

  1976                          0.37                 0.31       0.14            0.06        0.04       0.01

  1977                          0.27                 0.20       0.09            0.04        0.03       0.01

  1978                          3.49                 2.60       1.12            0.42        0.28       0.07

  1979                          0.31                 0.23       0.16            0.08        0.05       0.01

  1980                          0.60                 0.48       0.19            0.08        0.06       0.01

  1981                          0.33                 0.25       0.12            0.06        0.04       0.01

  1982                          0.76                 0.57       0.23            0.15        0.10       0.02

  1983                          0.20                 0.15       0.08            0.03        0.02       0.01

  1984                          0.49                 0.38       0.18            0.11        0.08       0.02

  1985                          1.46                 1.08       0.44            0.18        0.14       0.04

  1986                          0.21                 0.16       0.06            0.03        0.02       0.01

  1987                          0.04                 0.03       0.01            0.01        0.00       0.00

  1988                          0.29                 0.22       0.09            0.05        0.04       0.01

  1989                          1.40                 1.08       0.46            0.18        0.12       0.03

  1990                          1.20                 0.89       0.41            0.16        0.11       0.03

                                                                                                       

  Sorted results                                                                                       

  Prob.                         Peak                 96 hr      21 Day          60 Day      90 Day     Yearly

  0.03                          3.49                 2.60       1.12            0.42        0.28       0.07

  0.06                          1.77                 1.34       0.51            0.21        0.15       0.04

  0.10                          1.46                 1.08       0.46            0.18        0.14       0.04

  0.13                          1.40                 1.08       0.44            0.18        0.12       0.03

  0.16                          1.21                 0.96       0.41            0.17        0.12       0.03

  0.19                          1.20                 0.89       0.37            0.16        0.11       0.03

  0.23                          0.99                 0.76       0.36            0.15        0.10       0.03

  0.26                          0.97                 0.73       0.36            0.15        0.10       0.03

  0.29                          0.97                 0.71       0.34            0.14        0.10       0.02

  0.32                          0.84                 0.61       0.30            0.14        0.10       0.02

  0.35                          0.76                 0.57       0.23            0.13        0.09       0.02

  0.39                          0.60                 0.48       0.19            0.11        0.09       0.02

  0.42                          0.53                 0.38       0.18            0.11        0.08       0.02

  0.45                          0.51                 0.37       0.16            0.08        0.06       0.01

  0.48                          0.49                 0.36       0.15            0.08        0.05       0.01

  0.52                          0.37                 0.31       0.15            0.06        0.05       0.01

  0.55                          0.33                 0.26       0.14            0.06        0.05       0.01

  0.58                          0.33                 0.25       0.13            0.06        0.05       0.01

  0.61                          0.32                 0.23       0.12            0.06        0.05       0.01

  0.65                          0.31                 0.23       0.12            0.06        0.04       0.01

  0.68                          0.29                 0.23       0.11            0.05        0.04       0.01

  0.71                          0.29                 0.22       0.09            0.05        0.04       0.01

  0.74                          0.29                 0.21       0.09            0.05        0.04       0.01

  0.77                          0.27                 0.20       0.09            0.04        0.03       0.01

  0.81                          0.21                 0.16       0.08            0.04        0.03       0.01

  0.84                          0.21                 0.16       0.08            0.04        0.03       0.01

  0.87                          0.20                 0.15       0.06            0.03        0.02       0.01

  0.90                          0.13                 0.10       0.06            0.03        0.02       0.01

  0.94                          0.12                 0.09       0.03            0.02        0.02       0.00

  0.97                          0.04                 0.03       0.01            0.01        0.00       0.00

                                                                                                       

  **0.10**                      **1.45**             **1.08**   **0.46**        **0.18**    **0.14**   **0.03**

  Average of yearly averages:                                                                          0.02

                                                                                                       

  Inputs generated by pe4.pl -                                                                         
  8-August-2003                                                                                        

                                                                                                       

  Data used for this run:                                                                              

  Output File: NCsweet                                                                                 

  Metfile: w13722.dvf                                                                                  

  PRZM scenario:                NCSweetPotatoC.txt                                                     

  EXAMS environment file:                                                                              
  pond298.exv                                                                                          

  Chemical Name:                Chloropicrin                                                           

  Description                   Variable Name        Value      Units           Comments               

  Molecular weight              mwt                  164.4      g/mol                                  

  Henry\'s Law Const.           henry                0.00205    atm-m\^3/mol                           

  Vapor Pressure                vapr                 23.8       torr                                   

  Solubility                    sol                  1621       mg/L                                   

  Kd                            Kd                              mg/L                                   

  Koc                           Koc                  36.05      mg/L                                   

  Photolysis half-life          kdp                  1.3        days            Half-life              

  Aerobic Aquatic Metabolism    kbacw                31.42      days            Halfife                

  Anaerobic Aquatic Metabolism  kbacs                0.05       days            Halfife                

  Aerobic Soil Metabolism       asm                  15.71      days            Halfife                

  Hydrolysis:                   pH 7                 0          days            Half-life              

  Method:                       CAM                  8          integer         See PRZM               
                                                                                manual                 

  Incorporation Depth:          DEPI                 25         cm                                     

  Application Rate:             TAPP                 392        kg/ha                                  

  Application Efficiency:       APPEFF               1          fraction                               

  Spray Drift                   DRFT                 0          fraction of                            
                                                                application                            
                                                                rate applied to                        
                                                                pond                                   

  Application Date              Date                 15-4       dd/mm or dd/mmm                        
                                                                or dd-mm or                            
                                                                dd-mmm                                 

  Record 17:                    FILTRA                                                                 

                                IPSCND               1                                                 

                                UPTKF                                                                  

  Record 18:                    PLVKRT                                                                 

                                PLDKRT                                                                 

                                FEXTRC               0                                                 

  Flag for Index Res. Run       IR                   Pond                                              

  Flag for runoff calc.         RUNOFF               none       none, monthly                          
                                                                or                                     
                                                                total(average                          
                                                                of entire run)                         
  ----------------------------- -------------------- ---------- --------------- ----------- ---------- ----------

**B.4. Calculation of 1-in-10 year EEC using Weibull Probability
Plots.**

Output from the PRZM/EXAMS simulation is typically a series of estimated
environmental concentrations (EEC) corresponding to multiple years of
meteorological data. Each value is an estimate of the peak
concentrations corresponding to a specific averaging time (e.g., 96
hours, 21 days, etc.). The 24-hour averaging time is sometimes referred
to as the "Peak" concentration because the shortest time-step for a
PRZM/EXAMS simulations is one day. Therefore, the column of EEC values
reported in an output file for "Peak" refers to the maximum 24-hour EEC
for each of the meteorological years.

For ecological risk assessment, it is important to match the averaging
time to the duration of the toxicity study. However, of the multiple
years of data, which EEC should be selected in the calculation of the
RQ? The most conservative case would be to choose the maximum EEC for
each averaging time. An alternative would be to calculate an upper end
value that is less than the maximum. One statistic adopted by OPP for
use in ecological risk assessment is the 1-in-10 year return value. This
is the EEC that, on average, will be exceeded only once every 10 years.
It is important to note that for any single 10-year period, the 1-in-10
year value may be exceeded more than once, or not at all. The key
concept is that it represents the average probability of exceedance.

The 1-in-10 year statistic can be calculated using probability plotting
methods. There are a number of different techniques, but a common
practice in hydrology for plotting flow-duration and flood-frequency
curves is to use the plotting position associated with the Weibull
distribution (Helsel and Hirsch 1993). The general formula for
probability plotting is given by:

where p is the probability level, n is the number of data points, and a
is a coefficient that varies between 0 and 0.5. For the Weibull
distribution, a is 0 so the plotting position is

For the PRZM/EXAMS simulations presented above, there are 30 years of
meteorological data, so n = 30. To generate a Weibull probability plot
to estimate the exceedance probabilities, the data should be sorted in
descending order. That is, there is a lower probability of exceeding the
maximum EEC than the second highest EEC. The plotting position
associated with the maximum value is then calculated as follows:

The minimum and maximum probability values associated with the entire
data set will approach \[0, 1\] as the sample size increases. Sometimes
probability plots are used to estimate the values beyond the observed
range. To calculate the 1-in-10 year statistic, we need the EEC
associated with a probability value of 0.100. This value does not
correspond directly with any of the modeled values, but it is between
third highest value (p = 0.097) and fourth highest value (0.129). An
interpolation procedure is needed to estimate the EEC associated with p
= 0.100. A linear interpolation is commonly performed, although two
methods are available. One method involves fitting a line to the entire
set of data plotted on a Weibull probability plot. The second method
involves a linear interpolation only between the two values that
encompass the desired p-value. PRZM/EXAMS output is based on the Weibull
plotting positions with a straight line interpolation between just the
two data values that encompass the desired p-value of 0.100.

**Appendix C: Ecological Effects Data**

**Overview**

The toxicity testing required does not test all species of birds, fish,
mammals, invertebrates, and plants. Only two surrogate species for birds
(bobwhite quail and mallard) are used to represent all bird species
(over 1000 in the US, including subspecies), three species of freshwater
fish (rainbow trout, bluegill sunfish and fathead minnow) are used to
represent all freshwater fish species (over 900 in the US), and one
estuarine/marine fish species (sheepshead minnow) is used to represent
all estuarine/marine fish (over 300 in the US). The surrogate species
for terrestrial invertebrates is the honey bee, for freshwater
invertebrates the surrogate species is usually the waterflea (*Daphnia
magna*) and for estuarine/marine invertebrates the surrogate species are
mysid shrimp and eastern oyster. These four species are used to
represent all invertebrate species (over 10,000 in the US). For plants,
there are ten surrogate species used for all terrestrial plants and five
surrogate species used for all aquatic plants. There are over 20,000
plant species in the US which includes flowering plants, conifers,
ferns, mosses, liverworts, hornworts and lichens with over 27,000
species of algae worldwide.

The surrogate species testing scheme used in this assessment assumes
that a chemical's mechanism of action and toxicity found for avian
species is similar to that in all reptiles (over 300 species in the US).
The same assumption applies to amphibians (over 200 species in the US)
and fish; the tadpole stage of amphibians is assumed to have the same
sensitivity as a fish. Therefore, the results from toxicity tests on
surrogate species are considered applicable to other member species
within their class and are extrapolated to reptiles and amphibians. The
US species numbers noted in this section were taken from the Natureserve
website (
[[www.natureserve.org]{.underline}](http://www.natureserve.org/)
NatureServe: An online encyclopedia of life \[web application\].2000)
and the worldwide species number from Ecological Planning and
Toxicology, Inc.1996.

In the following sections, the shaded values in the tables are the ones
used in the current risk assessment.

**a. Toxicity to Terrestrial Animals**

**i. Birds, Acute and Subacute**

An acute oral toxicity study using the technical grade of the active
ingredient (TGAI) is required to establish the toxicity of chloropicrin
to birds. The avian oral LD~50~ is an acute, single-dose laboratory
study designed to estimate the quantity of toxicant required to cause
50% mortality in a test population of birds. The preferred test species
is either the mallard, a waterfowl, or bobwhite quail, an upland
gamebird. The TGAI is administered by oral intubation to adult birds,
and the results are expressed as LD~50~ milligrams (mg) active
ingredient (a.i.) per kilogram (kg) of body weight. Toxicity category
descriptions are the following:

If the LD~50~ is *less than 10 mg a.i./kg*, then the test substance is
*very highly toxic*.

> If the LD~50~ is *10-to-50 mg a.i./kg*, then the test substance is
> *highly toxic*.
>
> If the LD~50~ is *51-to-500 mg a.i./kg*, then the test substance is
> *moderately toxic.*
>
> If the LD~50~ is *501-to-2,000 mg a.i./kg*, then the test substance is
> *slightly toxic.*
>
> If the LD~50~ is *greater than 2,000 mg a.i./kg*, then the test
> substance is *practically nontoxic.*

Acute oral testing on chloropicrin is needed for risk assessment.

Two dietary studies using the TGAI are usually required to establish the
toxicity of pesticides to birds. These avian dietary LC~50~ tests, using
the mallard and bobwhite quail, are acute, eight-day dietary laboratory
studies designed to estimate the quantities of toxicant in the feed
required to cause 50% mortality in the two respective test populations
of birds. The TGAI is administered by mixture to juvenile birds\' diets
for five days followed by three days of \"clean\" diet, and the results
are expressed as LC~50~ parts per million (ppm) active ingredient (a.i.)
in the diet. Toxicity category descriptions are the following:

> If the LC~50~ is *less than 50 ppm a.i.*, then the test substance is
> *very highly toxic*.
>
> If the LC~50~ is *50-to-500 ppm a.i.*, then the test substance is
> *highly toxic*.
>
> If the LC~50~ is *501-to-1,000 ppm a.i.*, then the test substance is
> *moderately toxic.*
>
> If the LC~50~ is *1001-to-5,000 ppm a.i.*, then the test substance is
> *slightly toxic.*
>
> If the LC~50~ is *greater than 5,000 ppm a.i.*, then the test
> substance is *practically nontoxic.*

However, dietary exposure is not considered to be the primary or even a
substantial route of avian exposure to chloropicrin, and thus avian
dietary toxicity data are not currently needed for risk assessment.
Inhalation is expected to be the primary route of exposure and thus
acute inhalation toxicity data on chloropicrin are needed for risk
assessment.

**ii. Birds, Chronic**

Chronic/sub-chronic inhalation testing with chloropicrin is needed to
assess risk to birds in part because of the potential for repeated or
continuous exposure resulting from multiple fields being treated on
differing days within a given geographic area.

**iii. Mammalian Toxicity Data (from HED)**

+-----------------+---------------------+------------------------------+
| **Chloropicrin  |                     |                              |
| Toxicity        |                     |                              |
| Profile (from   |                     |                              |
| HED 1/31/05     |                     |                              |
| review)**       |                     |                              |
+=================+=====================+==============================+
| **Guideline     | **MRID No.          | **Results**                  |
| No./Study       | (year)/Clas         |                              |
| Type**          | sification/Exposure |                              |
|                 | Conditions**        |                              |
+-----------------+---------------------+------------------------------+
| **870.1100**    | 05014376 (1976)     | **LD~50~ = 37.5 mg/kg**      |
|                 |                     |                              |
| Acute Oral -    | Ac                  | **Toxicity Category I**      |
| Rat             | ceptable/Guideline. |                              |
+-----------------+---------------------+------------------------------+
| **870.1200**    | 05014376 (1976)     | **LD~50~ = 100 mg/kg**       |
|                 |                     |                              |
| Acute Dermal -  | A                   | **Toxicity Category I**      |
| Rat             | cceptable/Guideline |                              |
+-----------------+---------------------+------------------------------+
| **870.1300**    | 45117901 (1999)     | No deaths seen at any dose   |
|                 |                     | level. Clinical obs. normal  |
| Acute           | Accep               | before and after exposure.   |
| Inhalation -    | table/Non-Guideline | Body wt. gains may been      |
| Mouse           |                     | decreased at HDT only (8% of |
|                 | Head only study, 4  | initial body wt. in control  |
|                 | Albino              | and 2% at the HDT).          |
|                 | Swiss-Webster male  |                              |
|                 | mice/grp exposed to | -The exposure level at 50%   |
|                 | 0.99, 3.20, 4.20,   | RD (RD50) was 2.34 ppm with  |
|                 | 7.25, 10.00, 14.50  | 95% CI of 1.84 to 2.98 ppm   |
|                 | ppm (analytical     | or RD50 of 0.016 mg/L and    |
|                 | concen.)or 0.00664, | 95% CI of 0.012 mg/L to      |
|                 | 0.0215, 0.0282,     | 0.020 mg/L.                  |
|                 | 0.0486, 0.0671,     |                              |
|                 | 0.0973 mg/L         | -0% depression in the        |
|                 | (calculated         | respiration rate was plotted |
|                 | analytical          | by the % depression in the   |
|                 | concen.)of gaseous  | respiration rate reported in |
|                 | CP for 30 mins.     | the study versus log         |
|                 |                     | exposure level and           |
|                 |                     | extrapolating the graph to   |
|                 |                     | 0% depression. The RD0       |
|                 |                     | respiratory depression       |
|                 |                     | occurs around 0.0017 to      |
|                 |                     | 0.0019 mg/L.                 |
+-----------------+---------------------+------------------------------+
| **870.1300**    | 45117902 (1999)     | LC50 \[typo corrected\] was  |
|                 |                     | 17 ppm (M) and 19 ppm (F).   |
| Acute           | Accep               |                              |
| Inhalation -    | table/Non-Guideline | Death only occurred at 2 top |
| Rat             |                     | dose levels up to 2 days     |
|                 | Whole body          | post-exposure.               |
|                 | inhalation study, 5 |                              |
|                 | Sprague Dawley      | Clinical signs: obs noted at |
|                 | rats/sex/grp were   | all dose levels, labored     |
|                 | exposed to 0, 10.6, | breathing, gasping,          |
|                 | 18.0, or 28.5 ppm   | decreased activity, nasal    |
|                 | (analytical) or 0,  | discharge, salivation, moist |
|                 | 0.071, 0.121, 0.158 | rales. Top 2 levels produced |
|                 | mg/L (calculated)   | gasping for last 2 hrs of    |
|                 | of aerosolized CP   | exposure.                    |
|                 | for 4-hrs and held  |                              |
|                 | for 2 days after    | Gross pathology: Liver,      |
|                 | exposure. Particle  | adrenal wts, and             |
|                 | sizes had a MMAD    | histological findings        |
|                 | from 4.85 µm to     | increased at HDT.            |
|                 | 6.1µm with a GDS of | Histological findings of     |
|                 | 1.4 to 1.6.         | respiratory tract were seen  |
|                 |                     | at all dose levels and       |
|                 |                     | damage to the lungs, such as |
|                 |                     | congestion, bronchiole       |
|                 |                     | mucosal edema, necrosis, and |
|                 |                     | cellular infiltrates.        |
|                 |                     |                              |
|                 |                     | -No NOAEL demonstrated.      |
|                 |                     |                              |
|                 |                     | LOAEL = 10.6 ppm or 0.071    |
|                 |                     | mg/L (LDT).                  |
+-----------------+---------------------+------------------------------+
| 870.2400C       | N/A                 | reserved                     |
|                 |                     |                              |
| Primary Eye     |                     |                              |
| Irritation -    |                     |                              |
| Rabbit          |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.2500**    | 05014376 (1976)     | Corrosive                    |
|                 |                     |                              |
| Primary Skin    | A                   | **Toxicity Category I**      |
| Irritation -    | cceptable/Guideline |                              |
| Rabbit          |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.2600**    | N/A                 | Reserved                     |
|                 |                     |                              |
| Dermal          |                     |                              |
| Sensitization   |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.3100**    |                     | Not required by the Agency   |
|                 |                     |                              |
| Subchronic      |                     |                              |
| Feeding - Rat   |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.3100**    |                     | Not required by the Agency   |
|                 |                     |                              |
| Subchronic      |                     |                              |
| Feeding - Mice  |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.3100**    |                     | Not required by the Agency   |
|                 |                     |                              |
| Subchronic      |                     |                              |
| Feeding - Mice  |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.3150**    |                     | Not required by the Agency   |
|                 |                     |                              |
| Subchronic      |                     |                              |
| Feeding - Dog   |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.3200**    |                     | Reserved                     |
|                 |                     |                              |
| 21-Day Dermal - |                     |                              |
| Rat             |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.3465**    | 43063201 (1993)     | NOAEL = 0.3 ppm (0.002       |
|                 |                     | mg/L/day)                    |
| 13-Week         | A                   |                              |
| Inhalation -    | cceptable/Guideline | LOAEL = 1.0 ppm (0.007       |
| Mouse           |                     | mg/L/day) based on decreased |
|                 | 0, 0.3, 1.0, or3.0  | body weight and food         |
|                 | ppm in a whole-body | consumption, increased       |
|                 | chamber, 6 h/day, 5 | absolute and relative lung   |
|                 | days/week for 13    | weights in both sexes, and   |
|                 | weeks               | histopathological lesions of |
|                 |                     | the nasal cavity and lungs   |
|                 |                     | of females.                  |
+-----------------+---------------------+------------------------------+
| **870.3465**    | 43063201 (1993)     | NOAEL = 0.3 ppm (0.002       |
|                 |                     | mg/L/day)                    |
| 13-Week         | A                   |                              |
| Inhalation -    | cceptable/Guideline | LOAEL = 1.0 ppm (0.007       |
| Rat             |                     | mg/L/day), based on          |
|                 | 0, 0.3, 1.0, or3.0  | increased lung weights of    |
|                 | ppm in a whole-body | both sexes, and              |
|                 | chamber, 6 h/day, 5 | histopathological changes in |
|                 | days/week for 13    | the nose of females and      |
|                 | weeks               | lungs of males and females.  |
+-----------------+---------------------+------------------------------+
| **870.3700**    | 42740602 (1993)     | Maternal NOAEL = 0.4 ppm     |
|                 |                     | (0.003 mg/L/day)             |
| Inhalation      | A                   |                              |
| Developmental   | cceptable/Guideline | Maternal LOAEL = 1.2 ppm     |
| Toxicity - Rat  |                     | (0.008 mg/L/day) based on    |
|                 | 0, 0.4, 1.2, or 3.5 | mortality, decreased body    |
|                 | ppm in a whole-body | weight and food consumption, |
|                 | inhalation chamber, | and signs consistent with CP |
|                 | 6 h/day on GDs      | toxicity.                    |
|                 | 6-15.               |                              |
|                 |                     | Developmental NOAEL \> 3.5   |
|                 |                     | ppm (0.024 mg/L)             |
|                 |                     |                              |
|                 |                     | Developmental LOAEL= 3.5 ppm |
|                 |                     | (0.024 mg/L), based on       |
|                 |                     | decreased pup body weights.  |
+-----------------+---------------------+------------------------------+
| **870.3700**    | 42740601 (1993)     | Maternal NOAEL is 0.4 ppm    |
|                 |                     | (0.003 mg/L)                 |
| Inhalation      | A                   |                              |
| Developmental   | cceptable/Guideline | Maternal LOAEL is 1.2 ppm    |
| Toxicity -      |                     | (0.008 mg/L), based on       |
| Rabbit          | 0, 0.4, 1.2, or 2.0 | mortality, body weight loss, |
|                 | ppm in a whole-body | and decreased food           |
|                 | inhalation chamber, | consumption.                 |
|                 | 6 h/day, on GDs     |                              |
|                 | 7-29.               | Developmental NOAEL= 0.4 ppm |
|                 |                     | (0.003 mg/L)                 |
|                 |                     |                              |
|                 |                     | Developmental LOAEL= 1.2 ppm |
|                 |                     | (0.008 mg/L), based on       |
|                 |                     | abortions and decreased      |
|                 |                     | fetal weights.               |
+-----------------+---------------------+------------------------------+
| **870.3800**    | 43391901 (1994)     | Parental systemic NOAEL \>   |
|                 |                     | 1.5 ppm (0.0101 mg/L)        |
| Inhalation      | A                   |                              |
| 2-Generation    | cceptable/guideline | Parental systemic LOAEL not  |
| Reproductive    |                     | identified                   |
| Toxicity -      | 0, 0.5, 1.0, or 1.5 |                              |
|                 | ppm in whole body   | Offspring NOAEL \> 1.5 ppm   |
| (Main study)    | inhalation chamber  | (0.0101 mg/L)                |
|                 |                     |                              |
| Rat             | **Note: Offspring   | Offspring LOAEL not          |
|                 | not directly        | identified                   |
|                 | exposed until PND   |                              |
|                 | 28**                | Reproductive NOAEL \> 1.5    |
|                 |                     | ppm (0.0101 mg/L)            |
|                 |                     |                              |
|                 |                     | Reproductive LOAEL not       |
|                 |                     | identified                   |
+-----------------+---------------------+------------------------------+
| **870.3800**    | 46427801 (conducted | No treatment-related         |
|                 | 1992, study report  | mortality, clinical signs,   |
| Range-finding,  | 1996)               | or necropsy findings in any  |
| Inhalation      |                     | parental males or females,   |
| 2-Generation    | 0, 0.4, 1.0, or 2.0 | and no treatment-related     |
| Reproductive    | ppm whole body for  | effects on reproductive      |
| Toxicity - Rat  | 6hrs/day, 7         | parameters. Mean body weight |
|                 | days/week during    | and weight gain decreased in |
|                 | premating (14 days) | high-dose group (1-3% M&     |
|                 | and gestation day   | 5-6% F) beginning at week 1. |
|                 | 0-20.               | Maternal body weight was     |
|                 |                     | decreased 5-8% and decreased |
|                 |                     | 17% during gestation. Food   |
|                 |                     | consumption decreased 8-14%  |
|                 |                     | in males and 14% in females  |
|                 |                     | during premating and 7%      |
|                 |                     | during gestation. Litter     |
|                 |                     | size decreased 33% and       |
|                 |                     | uterine implantation sites   |
|                 |                     | decreased 30% in the         |
|                 |                     | high-dose group.             |
+-----------------+---------------------+------------------------------+
| **870.4100**    | 43744301 (1995)     | Only clinical toxicity       |
|                 |                     | observed was salivation      |
| Chronic Feeding | A                   | after dosing in high-dose    |
| Toxicity-Rat    | cceptable/guideline | male and female rats.        |
|                 |                     | Dose-related increase in     |
|                 | Gavage at 0, 0.1,   | incidence of subcutaneous    |
|                 | 1.0, or 10          | masses of skin of females    |
|                 | mg/kg/day for 104   | related to the increased     |
|                 | weeks.              | incidence of mammary         |
|                 |                     | fibroadenomas.               |
|                 |                     | Hyper-keratosis and          |
|                 |                     | hyperplasia of the           |
|                 |                     | nonglandular stomach in both |
|                 |                     | sexes. Females had           |
|                 |                     | dose-related increase in     |
|                 |                     | incidence of fibroadenoma of |
|                 |                     | the mammary gland at         |
|                 |                     | high-dose. Increased rate of |
|                 |                     | C-cell hyperplasia of the    |
|                 |                     | thyroid in high-dose         |
|                 |                     | females.                     |
|                 |                     |                              |
|                 |                     | NOAEL = 0.1 mg/kg/day \[F\]  |
|                 |                     |                              |
|                 |                     | NOAEL = 1.0 mg/kg/day \[M\]  |
|                 |                     |                              |
|                 |                     | LOAEL = 1.0 mg/kg/day \[F\], |
|                 |                     | based on periportal          |
|                 |                     | hepatocyte vacuolation and   |
|                 |                     | thyroid C-cell hyperplasia   |
|                 |                     | and stomach lesions at the   |
|                 |                     | high-dose.                   |
|                 |                     |                              |
|                 |                     | LOAEL = 10 mg/kg/day \[M\],  |
|                 |                     | basedon on stomach lesions.  |
+-----------------+---------------------+------------------------------+
| **870.4100**    | 43196301(1994)      | NOAEL \[M\] = 0.1 mg/kg/day  |
|                 |                     |                              |
| Chronic Feeding | A                   | NOAEL \[F\] = 1.0 mg/kg/day  |
| Toxicity - Dog  | cceptable/guideline |                              |
|                 |                     | LOAEL \[M\] = 1.0 mg/kg/day, |
|                 | 0, 0.1, 1.0, or 5.0 | based on gastrointestinal    |
|                 | mg/kg/day for one   | irritation (vomiting and     |
|                 | year (capsule).     | diarrhea), and blood         |
|                 |                     | chemistry alterations,       |
|                 |                     |                              |
|                 |                     | LOAEL \[F\] = 5.0 mg/kg/day, |
|                 |                     | based on gastrointestinal    |
|                 |                     | irritation (vomiting and     |
|                 |                     | diarrhea), microcytic        |
|                 |                     | hypochromatic anemia, and    |
|                 |                     | blood chemistry alterations. |
+-----------------+---------------------+------------------------------+
| **870.4200**    | 43632201 (1997)     | NOAEL = 0.1 ppm (0.0007      |
|                 |                     | mg/L)                        |
| Carcinogenicity | A                   |                              |
| Inhalation -    | cceptable/guideline | LOAEL = 0.5 ppm (0.0034      |
| Mouse (78       |                     | mg/L), based on systemic     |
| weeks)          | 0, 0.1, 0.5, or 1.0 | toxicity and irritation,     |
|                 | ppm for 78 weeks    | based on decreased body      |
|                 |                     | weights and gains, increased |
|                 |                     | lung weights, and            |
|                 |                     | histological changes in the  |
|                 |                     | nasal cavity, upper          |
|                 |                     | respiratory tract and lungs. |
|                 |                     |                              |
|                 |                     | No significant               |
|                 |                     | treatment-related increase   |
|                 |                     | in tumors.                   |
+-----------------+---------------------+------------------------------+
| **870.4200**    | 05014915 (1978)     | High-incidence of early      |
|                 |                     | death in CP dose rats. No    |
| Carcinog        | supplemental        | neoplasm observed at higher  |
| enicity/gavage- |                     | incidences in dosed rats     |
| Mouse/Rat       | Rats: \[M\]: 0, 25  | from controls. Rapid         |
| \[bioassay\]    | or 26 mg/kg/day     | decrease in survival after   |
|                 |                     | first year in both sexes of  |
|                 | \[F\]: 0, 20, or 22 | mice.                        |
|                 | mg/kg/day           |                              |
|                 |                     | Proliferative lesions of     |
|                 | Mice \[M\]: 0, 66   | squamous epithelium of the   |
|                 | mg/kg/day           | forestomach of mice included |
|                 |                     | two carcinomas and a         |
|                 | \[F\]: 0, 33        | papilloma. Statistical       |
|                 | mg/kg/day           | analysis did not demonstrate |
|                 |                     | related to CP. Bioassay of   |
|                 |                     | CP did not permit evaluation |
|                 |                     | of carcinogenicity due to    |
|                 |                     | short survival time of mice  |
|                 |                     | and rats.                    |
+-----------------+---------------------+------------------------------+
| **870.4300**    | 43755301 (1995)     | NOAEL =0.1 ppm (0.0007 mg/L) |
|                 |                     |                              |
| Chronic         | A                   | LOAEL = 0.5 ppm (0.0034      |
| Inhalation      | cceptable/guideline | mg/L), based on increased    |
| Toxicity/Carci  |                     | mortality rate and decreased |
| nogenicity-Rat. | 0, 0.15, 0.5, or    | mean survival time in males, |
| (2 year)        | 1.0 ppm in a whole  | and transiently decreased    |
|                 | body inhalation     | body weight gains in both    |
|                 | chamber for 6       | sexes.                       |
|                 | hrs/day, 5days/week |                              |
|                 | for up to 108       | Port of entry NOAEL = 0.5    |
|                 | weeks.              | ppm                          |
|                 |                     |                              |
|                 |                     | Port of entry LOAEL = 1.0    |
|                 |                     | ppm (males), based on severe |
|                 |                     | rhinitis of the anterior     |
|                 |                     | nasal cavity.                |
+-----------------+---------------------+------------------------------+
| **870.5100**    | 41960801 (1990)     | S9-activated CP is Mutagenic |
|                 |                     | in *Salmonella typhimurium*  |
| Bacterial       | A                   | strains TA98,and TA100.      |
| Reverse         | cceptable/guideline |                              |
| Mutation Test   |                     |                              |
| (Ames Assay)    |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.5300**    | 41960803 (1990)     | CP ranging from 0.038 to     |
|                 |                     | 0.75 nL/mL-S9 and 0.89 to 16 |
| *Muta           | A                   | nL/mL +S9 did not induce a   |
| genic-*Lymphoma | cceptable/guideline | mutagenic response in two    |
| Mutation-Mouse  |                     | independently performed      |
|                 |                     | mouse lymphoma forward       |
|                 |                     | mutation assays.             |
+-----------------+---------------------+------------------------------+
| **870.5375**    | 41960802 (1990)     | Nonactivated doses of CP     |
|                 |                     | from 0.75 to 1 nL/mL induced |
| *In Vitro*      | A                   | a reproducible and           |
| Chromosomal     | cceptable/guideline | significant clastogenic      |
| Aberration in   |                     | response in Chinese hamster  |
| Chinese Hamster |                     | ovary (CHO) cells harvested  |
| Ovary           |                     | 12 hours post-treatment.     |
|                 |                     |                              |
|                 |                     | Nonactivated CP was          |
|                 |                     | clastogenic over a narrow    |
|                 |                     | range of cytotoxic           |
|                 |                     | concentrations. CP in the    |
|                 |                     | absence of S9 activation is  |
|                 |                     | a clastogen in this          |
|                 |                     | mammalian test system.       |
+-----------------+---------------------+------------------------------+
| **870.5395**    | 41960804 (1990)     | CP was not genotoxic in      |
|                 |                     | primary rat hepatocytes over |
| Unscheduled DNA | A                   | a concentration range (0.3   |
| Synthesis-Rat   | cceptable/guideline | to 6 nL/mL) that included    |
|                 |                     | moderately cytotoxic levels. |
|                 |                     | CP showed no evidence of     |
|                 |                     | UDS.                         |
+-----------------+---------------------+------------------------------+
| **870.6200**    |                     | Not required by the Agency   |
|                 |                     |                              |
| Inhalation      |                     |                              |
| Acute           |                     |                              |
| Neurotoxicity - |                     |                              |
| Rats            |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.6200**    |                     | Not required by the Agency   |
|                 |                     |                              |
| Feeding         |                     |                              |
| Subchronic      |                     |                              |
| Neurotoxicity - |                     |                              |
| Rats            |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.7485**    |                     | Not available.               |
|                 |                     |                              |
| Metabolism -    |                     |                              |
| Rat             |                     |                              |
+-----------------+---------------------+------------------------------+
| **870.7600**    |                     | Not required by the Agency   |
|                 |                     |                              |
| Dermal          |                     |                              |
| Penetration -   |                     |                              |
| Rat             |                     |                              |
+-----------------+---------------------+------------------------------+

**b. Toxicity to Freshwater Aquatic Animals**

**i. Freshwater Fish, Acute**

Two freshwater fish toxicity studies using the TGAI are required to
establish the toxicity of chloropicrin to fish. The preferred test
species are rainbow trout (a coldwater fish) and bluegill sunfish (a
warmwater fish). Results of these tests are tabulated below. The
toxicity category descriptions for freshwater and estuarine/marine fish
and aquatic invertebrates, are defined below in parts per million (ppm).

> If the LC~50~ is *less than 0.1 ppm a.i.*, then the test substance is
> *very highly toxic*.
>
> If the LC~50~ is *0.1-to-1.0 ppm a.i.*, then the test substance is
> *highly toxic*.
>
> If the LC~50~ is *greater than 1 and up through 10 ppm a.i.*, then the
> test substance is *moderately toxic.*
>
> If the LC~50~ is *greater than 10 and up through 100 ppm a.i.*, then
> the test substance is *slightly toxic.*
>
> If the LC~50~ is *greater than 100 ppm a.i.*, then the test substance
> is *practically nontoxic.*

**Table 3: Freshwater Fish Acute Toxicity - Chloropicrin Technical**

+--------------------+------+--------+------+----------------+--------+
| **Species/**       | **%  | **LC   | **   | **             | *      |
|                    | ai** | ~50~** | Toxi | MRID/Accession | *Study |
| **Flow-through or  |      |        | city | (ACC) No.      | Clas   |
| Static**           |      | **(    | Ca   | Author/Year**  | sifica |
|                    |      | ppb)** | tego |                | tion** |
|                    |      |        | ry** |                |        |
+====================+======+========+======+================+========+
| Bluegill Sunfish   | 99.0 | \<105  | at   | FTLR           | Suppl. |
|                    |      |        | l    | 4              |        |
| *(Lepomis          |      |        | east | 39/McCann/1972 |        |
| ma                 |      |        | hi   |                |        |
| crochirus)*/Static |      |        | ghly |                |        |
|                    |      |        | t    |                |        |
|                    |      |        | oxic |                |        |
+--------------------+------+--------+------+----------------+--------+
| Rainbow Trout      | 99.0 | \<     | Very | FTLR           | Suppl. |
|                    |      | 16.98  | hi   | 4              |        |
| (Oncorhynchus      |      |        | ghly | 25/McCann/1971 |        |
| sp.)/Static        |      |        | t    |                |        |
|                    |      |        | oxic |                |        |
+--------------------+------+--------+------+----------------+--------+

The requirement for two freshwater fish acute toxicity studies has not
been satisfied. Flow-through studies with measured concentrations are
needed to reduce uncertainty in the risk assessment.

**ii. Freshwater Fish, Chronic**

A freshwater fish early life-stage test is required for chloropicrin
since it is expected to be transported to water from the intended use
site, and one or more of the following conditions are met: (1) the
pesticide is intended for use such that its presence in water is likely
to be continuous or recurrent, (2) any aquatic acute LC~50~ or EC~50~ is
less than 1 ppm, and/or (3) the EEC in water is equal to or greater than
0.01 of any acute LC~50~ or EC~50~ value. The preferred test species is
rainbow trout.

The fish early life-stage is a laboratory test designed to estimate the
quantity of toxicant required to adversely effect the reproduction of a
test population of fish. The test should be performed using flow-through
conditions. The test material is administered into water containing the
test species, providing exposure throughout a critical life-stage, and
the results, generally, are expressed as a No Observed Adverse Effect
Concentration (NOAEC) in parts per million or parts per billion of
active ingredient. The No Observed Adverse Effect Concentration
represents an exposure concentration, at or below which biologically
significant effects will not occur to species of similar sensitivities.

**(iii) Freshwater Invertebrates, Acute**

A freshwater aquatic invertebrate toxicity test using the TGAI is
required to establish the toxicity of chloropicrin to aquatic
invertebrates. The preferred test organism is *Daphnia magna*, but early
instar amphipods, stoneflies, mayflies, or midges may also be used.
Results of this test are tabulated below.

+--------------+------+----------+---------+-------------+----------+
| **Table 5:   |      |          |         |             |          |
| Freshwater   |      |          |         |             |          |
| Invertebrate |      |          |         |             |          |
| Acute        |      |          |         |             |          |
| Toxicity**   |      |          |         |             |          |
| **-          |      |          |         |             |          |
| Ch           |      |          |         |             |          |
| loropicrin** |      |          |         |             |          |
+==============+======+==========+=========+=============+==========+
| **Species/** | **%  | **LC~50  | **T     | **MRI       | **Study  |
|              | ai** | ~/EC~50~ | oxicity | D/Accession | Classifi |
| **           |      | (ppb)**  | Cat     | (ACC) No.   | cation** |
| Flow-through |      |          | egory** | Au          |          |
| or Static**  |      |          |         | thor/Year** |          |
+--------------+------+----------+---------+-------------+----------+
| Daphnid      | [\>] | \< 71    | very    | 130704/Cody | Supp     |
|              | {.un |          | highly  | and         | lemental |
| *(Daphnia    | derl |          | toxic   | Shema/1983  |          |
| pu           | ine} |          |         |             |          |
| lex)*/static | 96.5 |          |         |             |          |
+--------------+------+----------+---------+-------------+----------+

^1^ Core (study satisfies guideline). Supplemental (study is
scientifically sound, but does not satisfy guideline).

The requirement for an acute freshwater invertebrate acute toxicity
study has not been satisfied. A flow-through study with measured
concentrations is needed to reduce uncertainty in the risk assessment.

**iv. Freshwater Invertebrate, Chronic**

A freshwater aquatic invertebrate life-cycle test is required for
chloropicrin because this degradate is expected to be transported to
water from the intended use site, and one or more of the following
conditions are met: (1) the pesticide is intended for use such that its
presence in water is likely to be continuous or recurrent, (2) any
aquatic acute LC~50~ or EC~50~ is less than 1ppm, and/or (3) the EEC in
water is equal to or greater than 0.01 of any acute LC~50~ or EC~50~
value. A flow-through study with measured concentrations is needed for
risk assessment.

**c. Toxicity to Estuarine and Marine Animals**

**i. Estuarine and Marine Fish, Acute**

Acute toxicity testing with estuarine/marine fish is required for
chloropicrin since the active ingredient and or degradates are expected
to reach the marine/estuarine environment due to its expected use in
coastal counties. The preferred test species is the sheepshead minnow.

**ii. Estuarine and Marine Fish, Chronic**

An estuarine/marine fish early life-stage toxicity test using
chloropicrin is reserved, pending submission and review of freshwater
fish chronic testing.

**iii. Estuarine and Marine Invertebrates, Acute**

Acute toxicity testing with estuarine/marine invertebrates is required
for chloropicrin because it is expected to reach the marine/estuarine
environment due to its expected use in coastal counties. The preferred
test species are mysid shrimp and eastern oyster.

**iv. Estuarine and Marine Invertebrate, Chronic**

An estuarine/marine invertebrate life-cycle toxicity test (Guideline
72-4b) using chloropicrin is reserved, pending submission and review of
freshwater invertebrate chronic testing.

> **d. Toxicity to Plants**
>
> **i. Terrestrial Plants**

Terrestrial plant Tier I seedling emergence and vegetative vigor testing
of a Typical End-Use product (TEP) is currently recommended for all
pesticides having outdoor uses (EFED Policy, Keehner. July 1999). For
seedling emergence and vegetative vigor testing, the following plant
species and groups should be tested: (1) six species of at least four
dicotyledonous families, one species of which is soybean (*Glycine max*)
and the second is a root crop, and (2) four species of at least two
monocotyledonous families, one of which is corn (*Zea mays*). Tier I
tests measure the response of plants, relative to a control, at a test
level that is equal to the highest use rate expressed as pounds active
ingredeint per acre (lbs ai/A). Tier II studies are required if the Tier
I studies indicate any of the test species, when exposed to the test
material, displayed a ≥25% inhibition or over-enhancement of various
growth parameters as compared to the control. This guideline has not
been satisfied.

> **ii. Aquatic Plants**

Aquatic plant testing is recommended for all pesticides having outdoor
uses (EFED Policy, Keehner. July 1999). The tests are performed on
species from a cross-section of the aquatic plant population. The
preferred test species are duckweed (*Lemna gibba*), marine diatom
(*Skeletonema costatum*), blue-green algae (*Anabaena flos-aquae*),
freshwater green alga (*Selenastrum capricornutum*), and a freshwater
diatom. Tier I aquatic plant testing is a maximum dose test designed to
quickly evaluate the toxic effects to the test species in terms of
growth and reproduction and to determine the need for additional aquatic
plant testing. Tier II aquatic plant testing is a multiple dose test of
the plants species that showed a phytotoxic effect to the pesticide
being tested at the Tier I level. Tier II testing is designed to
determine the detrimental effect levels of the chemical on the aquatic
plants which showed a greater than 50% detrimental effect in Tier I
testing.

**e. Toxicity to Non-target Insects**

An acute contact study with the honey bee (141-1) is required, since the
proposed uses are outdoors.

**Appendix D. The Risk Quotient Method and Levels of Concern**

Risk characterization integrates the results of the exposure and
ecotoxicity data to evaluate the likelihood of adverse ecological
effects. The means of this integration is called the quotient method.
Risk quotients (RQs) are calculated by dividing exposure estimates by
acute and chronic ecotoxicity values.

RQ = EXPOSURE/TOXICITY

RQs are then compared to OPP\'s levels of concern (LOCs). These LOCs are
used by OPP to analyze potential risk to nontarget organisms and the
need to consider regulatory action. The criteria indicate that a
pesticide used as directed has the potential to cause adverse effects on
nontarget organisms. LOCs currently address the following risk
presumption categories: (1) acute risks - regulatory action may be
warranted in addition to restricted use classification, (2) acute
restricted use - the potential for acute risk is high, but may be
mitigated through restricted use classification, (3) acute endangered
species - endangered species may be adversely affected, and (4) chronic
risk - the potential for chronic risk is high regulatory action may be
warranted. Currently, EFED does not perform assessments for chronic risk
to plants, acute or chronic risks to insects, or chronic risk from
granular/bait formulations to birds or mammals.

The ecotoxicity test values (measurement endpoints) used in the acute
and chronic risk quotients are derived from required studies. Examples
of ecotoxicity values derived from short-term laboratory studies that
assess acute effects are: (1) LC~50~ (fish and birds), (2) LD~50~ (birds
and mammals), (3) EC~50~ (aquatic plants and aquatic invertebrates) and
(4) EC~25~ (terrestrial plants). Examples of toxicity test effect levels
derived from the results of long-term laboratory studies that assess
chronic effects are: (1) LOAEL or LOAEC (birds, fish, and aquatic
invertebrates) and (2) NOAEL or NOAEC (birds, fish and aquatic
invertebrates). For birds, mammals, fish and aquatic invertebrates the
NOAEL or NOAEC generally is used as the ecotoxicity test value in
assessing chronic effects, although other values may be used when
justified. Risk presumptions and the corresponding RQs and LOCs, are
tabulated below.

**Table 1. Risk presumptions for terrestrial animals based on risk
quotients (RQ) and levels of concern (LOC).**

  -----------------------------------------------------------------------
  **Risk              **RQ**                                    **LOC**
  Presumption**                                                 
  ------------------- ----------------------------------------- ---------
  **Birds**                                                     

  **Acute Risk**      **EEC^1^/LC~50~ or LD~50~/ft^2^ or        **0.5**
                      LD~50~/day^3^**                           

  **Acute Restricted  **EEC/LC~50~ or LD~50~/ft^2^ or           **0.2**
  Use**               LD~50~/day (or LD~50~ \< 50 mg/kg)**      

  **Acute Endangered  **EEC/LC~50~ or LD~50~/ft^2^ or           **0.1**
  Species**           LD~50~/day**                              

  **Chronic Risk**    **EEC/NOAEC**                             **1**

  **Wild Mammals**                                              

  **Acute Risk**      **EEC/LC~50~ or LD~50~/ft^2^ or           **0.5**
                      LD~50~/day**                              

  **Acute Restricted  **EEC/LC~50~ or LD~50~/ft^2^ or           **0.2**
  Use**               LD~50~/day (or LD~50~ \< 50 mg/kg)**      

  **Acute Endangered  **EEC/LC~50~ or LD~50~/ft^2^ or           **0.1**
  Species**           LD~50~/day**                              

  **Chronic Risk**    **EEC/NOAEC**                             **1**
  -----------------------------------------------------------------------

**^1^ abbreviation for Estimated Environmental Concentration (ppm) on
avian/mammalian food items**

**^2^ mg/ft^2^**

**^3^ mg of toxicant consumed/day**

**LD~50~ \* wt. of bird**

**LD~50~ \* wt. of bird**

**Table 2. Risk presumptions for aquatic animals based on risk quotients
(RQ) and levels of concern (LOC).**

  ------------------------------- ------------------------------ ----------
  **Risk Presumption**            **RQ**                         **LOC**

  **Acute Risk**                  **EEC^1^/LC~50~ or EC~50~**    **0.5**

  **Acute Restricted Use**        **EEC/LC~50~ or EC~50~**       **0.1**

  **Acute Endangered Species**    **EEC/LC~50~ or EC~50~**       **0.05**

  **Chronic Risk**                **EEC/NOAEC**                  **1**
  ------------------------------- ------------------------------ ----------

**^1^ EEC = (ppm or ppb) in water**

**Table 3. Risk presumptions for plants based on risk quotients (RQ) and
levels of concern (LOC).**

  ------------------------------- ------------------------------ ---------
  **Risk Presumption**            **RQ**                         **LOC**

  Terrestrial and Semi-Aquatic                                   
  Plants                                                         

  Acute Risk                      EEC^1^/EC~25~                  1

  Acute Endangered Species        EEC/EC~05~ or NOAEC            1

  Aquatic Plants                                                 

  Acute Risk                      EEC^2^/EC~50~                  1

  Acute Endangered Species        EEC/EC~05~ or NOAEC            1
  ------------------------------- ------------------------------ ---------

^1^ EEC = lbs ai/A

^2^ EEC = (ppb/ppm) in water

**Appendix E. Data Requirement Tables**

  -----------------------------------------------------------------------------------------------------------------
  **Table A1(A).                                                                        
  Ecological Effects                                                                    
  Data Requirements                                                                     
  for: Chloropicrin**                                                                   
  ------------------- ----------------------- ------------- --------------------------- ---------------------------
  Guideline \#        Data Requirement        Are           MRID #'s                    Study Classification
                                              Additional                                
                                              Data Needed                               
                                              for Risk                                  
                                              Assessment?                               

  71-1(a)             Avian Acute Oral        Y             \-\-\-\-\-\-\-\-\-\-\--     \-\-\-\-\-\-\-\-\-\-\--

  \-\-\-\-\--         Avian Acute Inhalation  Y             \-\-\-\-\-\-\-\-\-\-\--     \-\-\-\-\-\-\-\-\-\--

  71-2(a)             Avian Dietary--quail    N             \-\-\-\-\-\-\-\-\-\-\--     \-\-\-\-\-\-\-\-\-\-\--

  71-2(b)             Avian Dietary--mallard  N             \-\-\-\-\-\-\-\-\-\-\--     \-\-\-\-\-\-\-\-\-\-\-\--

  \-\-\-\-\-\-\-\--   Avian                   Y             \-\-\-\-\-\-\-\-\-\-\-\--   \-\-\-\-\-\-\-\-\-\-\-\--
                      Subchronic/Chronic                                                
                      Inhalation                                                        

  72-1(a)             Fish Acute              Y             FTLR 439                    S
                      Toxicity--bluegill                                                

  72-1(b)             Fish Acute              Y             FTLR 425                    S
                      Toxicity--rainbow trout                                           

  72-2(a)             Aquatic Invertebrate    Y             130704                      S
                      Acute                                                             
                      Toxicity--freshwater                                              

  72-3(a)             Marine/Estuarine Acute  Y             \-\-\-\-\-\-\-\-\-\-\-\--   \-\-\-\-\-\-\-\-\-\-\-\--
                      Toxicity--Fish                                                    

  72-3(b)             Marine/Estuarine Acute  Y             \-\-\-\-\-\-\-\-\-\-\--     \-\-\-\-\-\-\-\-\-\-\-\--
                      Toxicity--Mollusk                                                 
                      (shell deposition)                                                

  72-3(c)             Marine/Estuarine Acute  Y             \-\-\-\-\-\-\-\-\-\-\--     \-\-\-\-\-\-\-\-\-\-\-\--
                      Toxicity--Shrimp                                                  

  72-4(a)             Fish Early Life         Y             \-\-\-\-\-\-\-\-\-\-\-\--   \-\-\-\-\-\-\-\-\-\-\-\--
                      Stage--freshwater                                                 

  72-4(a)             Fish Early Life Stage-- Reserved      \-\-\-\-\-\-\-\-\-\-\--     \-\-\-\-\-\-\-\-\-\-\-\--
                      marine/estuarine                                                  

  72-4(b)             Aquatic Invertebrate    Y             \-\-\-\-\-\-\-\-\-\--       \-\-\-\-\-\-\-\-\-\-\--
                      Life Cycle--freshwater                                            

  123-1(a)            Seedling                Y             \-\-\-\-\-\-\-\-\-\-\-\--   \-\-\-\-\-\-\-\-\-\-\--
                      Germination/Seedling                                              
                      Emergence--Tier II                                                

  123-1(b)            Vegetative Vigor--Tier  Y             \-\-\-\-\-\-\-\-\-\-\-\--   \-\-\-\-\-\-\-\-\-\-\--
                      II                                                                

  123-2               Aquatic Plant Growth -- Y                                         \-\-\-\-\-\-\-\-\-\--
                      Tier II                                                           

  141-1               Honeybee Acute Contact  Y             \-\-\-\-\-\-\-\-\-\-\-\--   \-\-\-\-\-\-\-\-\-\-\--

  A=Acceptable;                                                                         
  S=Supplemental;                                                                       
  U=Unnaceptable;                                                                       
  W=Waived; N/A=Not                                                                     
  Applicable; NA=Not                                                                    
  Available;                                                                            
  Inv.=Invalid;                                                                         
  R=Potentially                                                                         
  Repairable                                                                            
  -----------------------------------------------------------------------------------------------------------------

+----------+-----------------------+-----------+---------+------------+
| **Table  |                       |           |         |            |
| 1A (B).  |                       |           |         |            |
| Envir    |                       |           |         |            |
| onmental |                       |           |         |            |
| Fate     |                       |           |         |            |
| Data     |                       |           |         |            |
| Requ     |                       |           |         |            |
| irements |                       |           |         |            |
| for:     |                       |           |         |            |
| Chloro   |                       |           |         |            |
| picrin** |                       |           |         |            |
+==========+=======================+===========+=========+============+
| G        | Data Requirement      | Is Data   | MRID    | Study      |
| uideline |                       | Re        | #'s     | Clas       |
| \#       |                       | quirement |         | sification |
|          |                       | S         |         |            |
|          |                       | atisfied? |         |            |
+----------+-----------------------+-----------+---------+------------+
| 161-1    | Hydrolysis            | Y         | 4       | A          |
|          |                       |           | 3022401 |            |
+----------+-----------------------+-----------+---------+------------+
| 161-2    | Photodegradation in   | Y         | 4       | S          |
|          | Water                 |           | 2900201 |            |
+----------+-----------------------+-----------+---------+------------+
| 161-3    | Photodegradation on   | N/A       | NA      | W          |
|          | Soil                  |           |         |            |
+----------+-----------------------+-----------+---------+------------+
| 161-4    | Photodegradation in   | Y         | 0       | A          |
|          | Air                   |           | 5007865 |            |
+----------+-----------------------+-----------+---------+------------+
| 162-1    | Aerobic Soil          | Y         | 4       | S          |
|          | Metabolism            |           | 3613901 |            |
+----------+-----------------------+-----------+---------+------------+
| 162-2    | Anaerobic Soil        | N/A       | \-\-\   | \-\-\-\-\  |
|          | Metabolism            |           | -\-\-\- | -\-\-\-\-- |
|          |                       |           | \-\-\-- |            |
+----------+-----------------------+-----------+---------+------------+
| 162-3    | Anaerobic Aquatic     | Y         | 4       | S          |
|          | Metabolism            |           | 3759301 |            |
+----------+-----------------------+-----------+---------+------------+
| 162-4    | Aerobic Aquatic       | N/A       | \-\-\   | \-\-\-\-\  |
|          | Metabolism            |           | -\-\-\- | -\-\-\-\-- |
|          |                       |           | \-\-\-- |            |
+----------+-----------------------+-----------+---------+------------+
| 163-1    | Mobility-Column       | Y         | 4       | S          |
|          | Leaching              |           | 4191301 |            |
+----------+-----------------------+-----------+---------+------------+
| 163-2    | Laboratory Volatility | Y         | 4       | A          |
|          |                       |           | 3798601 |            |
+----------+-----------------------+-----------+---------+------------+
| 163-3    | Field Volatility      | Reserved  | \-\-\   | \-\-\-\-\  |
|          |                       |           | -\-\-\- | -\-\-\-\-- |
|          |                       |           | \-\-\-- |            |
+----------+-----------------------+-----------+---------+------------+
| 164-1    | Terrestrial Field     | N         | 4       | S          |
|          | Dissipation           |           | 3085101 |            |
+----------+-----------------------+-----------+---------+------------+
| 165-4    | Accumulation in Fish/ | N/A       | NA      | W          |
|          |                       |           |         |            |
|          | Bioconcentration      |           |         |            |
+----------+-----------------------+-----------+---------+------------+
| A=Acc    |                       |           |         |            |
| eptable; |                       |           |         |            |
| S=Suppl  |                       |           |         |            |
| emental; |                       |           |         |            |
| U=Unnac  |                       |           |         |            |
| eptable; |                       |           |         |            |
| W        |                       |           |         |            |
| =Waived; |                       |           |         |            |
| N/A=Not  |                       |           |         |            |
| App      |                       |           |         |            |
| licable; |                       |           |         |            |
| NA=Not   |                       |           |         |            |
| A        |                       |           |         |            |
| vailable |                       |           |         |            |
+----------+-----------------------+-----------+---------+------------+