2 

 

Problem Formulation for the Environmental Fate, 

Ecological Risk, Endangered Species, and Drinking 

Water Exposure Assessments in Support of the 

Registration Review of Aldicarb 

CAS Registry Number: 116-06-3 

PC Code: 098301 

DP Barcode: D398519 

Prepared by:

N.E. Federoff, Wildlife Biologist

R. David Jones, Ph.D, Senior Agronomist 

U. S. Environmental Protection Agency 

Office of Pesticide Programs 

Environmental Fate and Effects Division

Environmental Risk Branch IV

1200 Pennsylvania Ave., NW 

Mail Code 7507P 

Washington, DC 20460

Reviewed by: 

Greg Orrick, Environmental Scientist 

Christina Wendel, Biologist 

Brian Anderson, Branch Chief

April 4, 2012 

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TABLE OF CONTENTS

1. Purpose .................................................................................................................................... 4

2. Description of Regulatory Action ........................................................................................... 4

3. Conclusions from Previous Assessments................................................................................ 4

3.1. Ecological Risk Assessments ........................................................................................... 4

3.2. Drinking Water Exposure Assessments ........................................................................... 6

3.3. Clean Water Act Programs ............................................................................................... 8

3.3.1. Aquatic Life Criteria and Aquatic Life Benchmarks ................................................ 8

3.3.2. Impaired Water Bodies ............................................................................................. 9

4. Stressor Source and Distribution ............................................................................................ 9

4.1. Pesticidal Mechanism of Action .................................................................................... 10

4.2. Overview of Pesticide Use and Usage ........................................................................... 10

4.3. Environmental Fate and Transport ................................................................................. 15

5. Receptors............................................................................................................................... 20

5.1. Effects to Terrestrial Species .......................................................................................... 21

5.1.1. Birds and Mammals ................................................................................................ 21

5.1.2. Beneficial Insects .................................................................................................... 22

5.1.3. Plants ....................................................................................................................... 22

5.2. Effects to Aquatic Species .............................................................................................. 22

5.2.1. Parent Aldicarb Toxicity ............................................................................................ 22

5.2.1.1. Fish .......................................................................................................................... 22

5.2.1.2. Aquatic Invertebrates .............................................................................................. 23

5.2.1.3. Aquatic Plants ......................................................................................................... 24

5.3. Degradate Toxicity ......................................................................................................... 24

5.4. Incident Database Review .............................................................................................. 24

6. Ecosystems Potentially at Risk ............................................................................................. 27

7. Assessment Endpoints .......................................................................................................... 27

8. Conceptual Model ................................................................................................................. 28

8.1. Risk Hypothesis.............................................................................................................. 29

9. Analysis Plan ........................................................................................................................ 30

9.1. Measures of Exposure .................................................................................................... 31

9.2. Measures of Effect ......................................................................................................... 32

9.3. Integration of Exposure and Effects ............................................................................... 33

9.4. Deterministic and Probabilistic Assessment Methods ................................................... 34

9.5. Endangered Species Assessments .................................................................................. 34

9.6. Drinking Water Assessment ........................................................................................... 35

10. Endocrine Disruptor Screening Program .......................................................................... 35

11. Preliminary Identification of Data Gaps ........................................................................... 36

11.1. Ecological Effects ....................................................................................................... 40

12. References ......................................................................................................................... 41

Appendix A. Ecological Effects Data .......................................................................................... 60
4 

1. Purpose 

The purpose of this problem formulation is to provide an understanding of the environmental fate 

and ecological effects of the registered uses of aldicarb. Aldicarb is an insecticide, acaricide and 

nematicide in the carbamate group of cholinesterase inhibitors. This problem formulation 

provides a plan for analyzing data relevant to aldicarb and for conducting environmental fate and 

ecological risk, endangered species, and drinking water assessments for all current, active 

registrations. Additionally, this problem formulation is intended to identify data gaps, 

uncertainties, and potential assumptions used to address those uncertainties, relative to 

characterizing the ecological risk associated with the registered use of aldicarb. 

2. Description of Regulatory Action 

The Food Quality Protection Act of 1996 mandated the EPA to implement a new program for 

assessing the risks of pesticides, i.e., registration review1

. All pesticides distributed or sold in the 

United States must be registered by the Agency. The decision to register a pesticide is based on 

the consideration of scientific data and other factors showing that it will not cause unreasonable 

risks to human health, workers, or the environment when used as directed on product labeling. 

The registration review program is intended to ensure that, as the ability to assess risk evolves 

and as policies and practices change, all registered pesticides continue to meet the statutory 

standard of no unreasonable adverse effects to human health and the environment. Changes in 

science, public policy, and pesticide use practices will occur over time. Through the new 

registration review program, the Agency periodically reevaluates pesticides to ensure that as 

change occurs, products in the marketplace can be used safely. 

As part of the implementation of the new registration review program pursuant to Section 3(g) of 

the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), the Agency is beginning its 

evaluation to determine whether use of aldicarb continues to meet the FIFRA standard for 

registration. This problem formulation for the environmental fate and ecological risk 

assessments in support of the registration review is intended for the initial docket opening, which 

starts the public phase of the review process. 

3. Conclusions from Previous Assessments 

3.1. Ecological Risk Assessments 

In September 2007, the Agency issued a Reregistration Eligibility Decision (RED) for aldicarb 

(http://www.epa.gov/oppsrrd1/REDs/aldicarb_red.pdf). Key conclusions on exposure and risks 

to terrestrial and aquatic wildlife as well as relevant data gaps as they relate to these two 

assessments are listed below. RQs using alternative application rates and incorporation 

efficiencies (http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2005-0163-0156

and http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2005-0163-0203) were 

calculated later under addendums to the RED document. These RQs took into account the 99% 

soil incorporation rates of the specialized application equipment that is used to apply aldicarb. 

 

1 (http://www.epa.gov/oppsrrd1/registration_review/) 
5 

Note that a number of the uses in the assessments described below (e.g. potatoes and cotton) are 

no longer registered. 

Exposure and Risk to Terrestrial Organisms:

 The cotton scenario (4.05 lbs ai/A; banded side dress, 1 application) poses the highest 

use risk in the terrestrial environment to mammals and birds due to aldicarb levels in soil 

(highest acute RQ for small birds = 6400), followed by potato, sugar beet, peanuts and 

dry beans (RQ for small birds = 3000, 2800, 2800, 2600, respectively). 

 The acute risk, acute restricted use, and acute endangered species LOCs for birds and 

mammals are exceeded for all labeled crops (cotton, dry beans, sorghum, peanuts, 

potatoes, soybeans, sugar beets, sweet potatoes, citrus, pecans, ornamentals) due to 

aldicarb levels in soil at both maximum allowed label rates (1.05 to 10.05 lbs ai/A) and 

average use rates (0.6 to 3.1 lbs ai/A). 

 Acute levels of concern are consistently exceeded by a factor of greater than 100 and are 

frequently exceeded by more than 1000 for birds and mammals. 

 Granules left exposed on the surface appear to be the main source of exposure, but other 

sources such as residues of aldicarb taken up by plants and soil invertebrates (e.g., 

earthworms) may also serve as a means of exposure. 

 A single granule of TEMIK® 15G can kill a small bird or mammal. 

 Reproductive effects to birds at sub-lethal levels could not be assessed because of the 

lack of reproductive studies with aldicarb or itsdegradates. Due in part to high acute 

toxicity, it has been difficult to design an experiment that utilizes a dose low enough not 

to acutely intoxicate adult birds. 

 Reduction in seedling emergence and vegetative vigor to non-target terrestrial plants 

from runoff could not be assessed because of the lack of toxicity data. 

Exposure and Risk to Aquatic Organisms

 The cotton scenario (4.05 lbs ai/A; 1 application) poses the highest use risk in the aquatic 

environment to aquatic invertebrates and fish due to estimated levels of aldicarb and its 

degradates in surface water from runoff (highest acute and chronic RQs for freshwater 

invertebrates = 1.4 and 26.6, respectively), followed by pecans, soybeans, citrus, and 

potato (acute and chronic RQs of 0.60, 0.36, 0.15, 0.07 and 11.40, 6.76, 2.80, 1.40, 

respectively). 

 There is acute risk for both freshwater and estuarine/marine fish and invertebrates for all 

of the registered uses with the exception of potatoes for freshwater fish and invertebrates 

and estuarine/marine fish. 

 Based on the use of an estimated NOAEC for chronic effects in freshwater fish, the 

chronic level of concern is also exceeded for freshwater fish (larval and juvenile survival) 

for cotton, pecan, and soybean use patterns. 
6 

 Based on the use of an estimated NOAEC for reproductive effects in estuarine/marine 

fish, the chronic level of concern is exceeded for estuarine/marine fish for all crop 

scenarios. 

 Aldicarb residues are most likely to exceed levels of concern for fish and aquatic 

invertebrates in low-order streams because these streams are dominated by base flow 

conditions (where 100% of stream flow consists of discharged ground water), and most 

of the toxic residues are believed to form within the subsurface (especially within the 

saturated zone) and are conveyed by ground water. Higher-order streams are sustained 

by much larger contributing land areas, so there should be a greater dilution effect. 

 In addition to risk-based exposure estimates from modeling, there were also exceedances 

of the Agency levels of concern based on surface water residue monitoring data. 

3.2. Drinking Water Exposure Assessments 

 

There have been seven previous drinking water exposure assessments for aldicarb. In addition, 

aldicarb was a component of the cumulative risks of all the N-methyl carbamate pesticides which 

were considered in two assessments (Health Effects Division, 2005; OPP, 2007). 

The first aldicarb drinking water assessment was completed in 1999 and provided estimates of 

aldicarb in ground water based on monitoring data which had been summarized and analyzed by 

the registrant and Tier 1 estimated drinking water concentrations (EDWC) for surface water 

(Dutta, 1999). The maximum surface water EDWC as calculated by GENEEC was 88.5 μg·L-1. 

Maximum concentrations in ground water by region ranged from no detections in the Southwest 

to 187.2 μg·L-1 in New England. 

The first assessment was updated in September 1999 (DP 247759). The same ground water 

estimates were used in the update, but Tier II estimates for surface water were estimated for 

cotton, potatoes, and citrus. Citrus had the highest EDWCs with a 1-in-10-year peak EDWC of 

2.3 μg·L-1. 

The next drinking water assessment was in the first version of the EFED RED chapter for 

aldicarb (DP 246901). EDWCs were calculated for citrus in Florida, potatoes in Idaho, and 

cotton in Mississippi. In this assessment, the highest 1-in-10-year peak EDWC was for Idaho 

potatoes with 17.4 μg·L-1. The ground water assessment was the same as that presented in the 

previous assessments. 

The drinking water assessment in the 2003 EFED RED chapter was updated in 2005 (DP 

316754). This update included an assessment of surface-water source drinking water using the 

total toxic residues method (TTR) for estimating the exposure from aldicarb, aldicarb sulfoxide 

and aldicarb sulfone combined. For surface water, 3 crops were assessed: cotton, potatoes, and 

citrus. Cotton had the highest 1-in-10-year peak EDWC with 14.6 μg·L-1. For ground water, Tier 

1 estimates with SCI-GROW were calculated for the same 3 crops, with citrus having the highest 

EDWC at 4.95 μg·L-1. The ground water monitoring data were reassessed and some newer data 

were added to previous assessments. These newer data showed that concentrations in ground 
7 

water in excess of 20 μg·L-1 were still being found in the early 1990s. 

The drinking water exposure assessment for aldicarb was updated in 2006 (DP 333309). This 

assessment included aldicarb sulfoxide and sulfone as well as parent aldicarb. This was done to 

be consistent with the N-methyl carbamate cumulative assessment. Typical use rates were 

assessed rather than maximum label rates. Both surface and ground water sources were assessed. 

A Tier 2 simulation modeling approach was used for both ground water and surface water. 

Peanuts, cotton, citrus and potatoes were the uses assessed. For ground water, well setback 

distances were estimated using a high-end estimate of lateral ground water movement. The 

maximum EDWCs were for citrus in Florida for surface water with 10.2 μg·L-1 for a 30 year 

maximum concentration and for peanuts in Georgia for ground water with 6.5 μg·L-1 for a 30 

year maximum concentration with a 30 ft buffer in place around the well. 

A drinking water exposure assessment was conducted for a new use of aldicarb regarding 

expanding its use on potatoes in 6 additonal states, Colorado, Michigan, Minnesota, North 

Dakota, South Dakota, and Wyoming (DP 348436). This assessment determined that exposures 

in surface water and ground water would be less than previous assessments of potato use based 

on use restrictions and the nature of the soils and weather patterns in the new use states. 

An updated drinking water assessment for the use of aldicarb on tobacco was performed in 2009 

(DP 299881). This assessment corrected an error in the incorporation depth from a previous 

assessment. The reported 1-in-10-peak EDWC for this simulation was 0.71 μg·L-1. 

Aldicarb was considered as part of two cumulative risk assessments for the N-methyl carbamate 

insecticides. A preliminary assessment (Health Effects Division, 2005) included aldicarb, 

carbaryl, carbofuran, formetenate, methomyl, oxamyl, propoxur, methiocarb, pirimicarb, and 

thiodicarb. The assessment looked at three routes of exposure; dietary from food, dietary from 

drinking water, and residential exposure. 

The drinking water component of the preliminary assessment focused on areas where combined 

N-methyl carbamate (NMC) exposure is likely to be among the highest within each region as a 

result of total NMC usage and vulnerability of drinking water sources. This analysis was based 

on a probabilistic modeling approach that considers the full range of data. Exposures in drinking 

water to individuals were incorporated into the cumulative exposure assessment on a regionaland source water-specific basis (i.e., ground water and surface water, by region). The regional 

drinking water exposure assessments are intended to represent exposures from vulnerable 

drinking water sources resulting from typical NMC usage and reflect seasonal variations as well 

as regional variations in cropping and NMC use. In most of the country, NMC residues in 

drinking water sources are at levels that are not likely to contribute substantially to the multipathway cumulative exposure. However, it was found that NMC residues estimated for 

vulnerable private wells in some areas of Florida (primarily along the central ridge) and the 

southeastern coastal plain are major contributors to the cumulative NMC exposures. 

The revised N-methyl carbamate cumulative assessment (OPP, 2007) reflected some changes 

due to updates in the fate and transport data for some compounds due to the completion of the 

single chemical assessments, but also reflected changes in use patterns that had been implementd 
8 

or were expected to occur as a result of the reregistration process. These included restrictions on 

the use of aldicarb in Florida and the Atlantic Coastal Plain to protect ground water, the expected 

cancellation of carbofuran and the restrictions of the use of other N-methyl carbamates. The 

methods used in the revised assessment were essentially the same as those used in the 

preliminary assessment. This assessment that cumulative risks were below levels of concern if 

carbofuran was cancelled and certain uses for pesticides other than aldicarb were removed (e.g., 

methomyl on grapes). 

3.3. Clean Water Act Programs 

3.3.1. Aquatic Life Criteria and Aquatic Life Benchmarks 

The Clean Water Act requires the Agency to publish water quality criteria that accurately reflect 

the latest scientific knowledge on the kind and extent of all identifiable effects on health and 

welfare that might be expected from the presence of pollutants in any body of water, including 

ground water. While these recommended criteria do not, in themselves, impose any 

requirements, states and authorized tribes can use them to develop water quality standards. An 

Aquatic Life Ambient Water Quality Criteria document has not been published for aldicarb2

. 

The Office of Pesticide Programs (OPP) publishes aquatic life benchmarks for freshwater species 

based on toxicity values for the most sensitive species from the most recent risk assessments. 

For aldicarb, aquatic life benchmarks have been published3

. Acute benchmarks have been 

established for fish (26 μg·L-1), invertebrates (10 μg·L-1) and aquatic plants (> 5000 μg·L-1), 

while chronic benchmarks have been established for fish (0.46 μg·L-1) and invertebrates (1 μg·L1

). The chronic benchmark is based on the acute toxicity value (which was lower than the lowest 

available chronic toxicity value), and therefore may underestimate chronic toxicity. In addition, 

acute benchmarks have been established for the aldicarb sulfoxide (3570 μg·L-1 for fish and 21.5 

μg·L-1 for invertebrates) and aldicarb sulfone (21,000 μg·L-1 for fish and 140 μg·L-1 for 

invertebrates) degradates. 

Table 3-1. OPP Freshwater Aquatic Life Benchmarks for Aldicarb (in μg/L). 

Chemical Fish Invertebrates Vascular Plants

Acute Chronic Acute Chronic Acute 

aldicarb 26 0.46 10 1 >5000 

aldicarb sulfoxide 3570 NS1 21.5 NS NS 

aldicarb sulfone 21,000 NS 140 NS NS 

1 NS – not specified. There were no benchmarks published for these categories. 

The California Environmental Protection Agency. (CDPR) has a no specific water quality 

performance goal for protecting aquatic life for aldicarb or its degradates4

. 

 

2 http://www.epa.gov/waterscience/criteria/

3 http://www.epa.gov/oppefed1/ecorisk_ders/aquatic_life_benchmark.htm#benchmarks

4 http://www.swrcb.ca.gov/water_issues/programs/water_quality_goals/
9 

3.3.2. Impaired Water Bodies 

There are currently no water bodies which have been found to be impaired by aldicarb or its 

degradates under Section 303(d) of the Clean Water Act5

. 

4. Stressor Source and Distribution 

Chemical and Physical Properties

 Common Name: aldicarb 

Chemical Name: 2-methyl-2(methylthio)propionaldehyde O-

(methylcarbamoyl)oxime 

 CAS No. 116-06-3 

 PC Code: 098301 

 SMILES code C(C)(C)(C=NOC(=O)NC)SC 

 Molecular Formula: C7 H14 N2O2S 

 Molecular Weight: 190.2 g/mol 

 Density: 0.565 g/cm3

 

 Melting Point: 96.5o C 

 Boiling Point: decomposes above 100o C 

 Water Solubility: 5191 mg/L (pH 7, 20o C) 

 Octanol/Water Partition Coefficient (KOW): 11.5 

 Formulations: granules (e.g., active ingredient 15.0%, Inert 

ingredients 85.0%) 

 

5 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885
10 

Figure 4-1. Chemical structure of aldicarb and its oxidative transformation products

4.1. Pesticidal Mechanism of Action 

Aldicarb (2-methyl-2-(methylthio)propionaldehyde O-(methylcarbamoyl)oxime), also known by 

the trade name Temik, is a granular pesticide that was first registered for use on cotton in 1970. 

Aldicarb is a systemic insecticide, acaricide, and nematicide. It is a potent cholinesterase (ChE) 

inhibitor causing inhibition of erythrocyte acetylcholinesterase as well as plasma butyryl ChE by 

binding to the active site of the enzyme. Acetylcholinesterase is an enzyme necessary for the 

degradation of the neurotransmitter acetylcholine (ACh) and subsequent cessation of synaptic 

transmission. Inhibition of these enzymes in animals (i.e. terrestrial and aquatic invertebrates, 

fish, birds, amphibians, reptiles, mammals) results in the accumulation of ACh at cholinergic 

nerve endings and continual nerve stimulation leading to death. 

4.2. Overview of Pesticide Use and Usage 

There are currently two end use product labels for aldicarb, Temik 15G (Reg No. 263-330) and 

Meymik 15G (Reg. No. 87895-1). Temik is being voluntarily cancelled as of December 14, 2014 

and the product cannot be used after December 31, 2018. Meymik has an essentially identical 

label and was recently registered in December, 2011. There are 6 crops listed for use of aldicarb 

on the Meymik and Temik labels: cotton, dry beans, peanuts, soybeans, sugar beets, and sweet 

potatoes. Table 4.1 lists the use pattern of maximum exposure for the current uses of aldicarb. 

The remaining use on these labels reflect label amendments to remove uses that previously 

exceeded risk thresholds as was determined during reregistration. 

Aldicarb cannot be applied in Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, 

New York, Pennsylvania, Rhode Island, Vermont, or Wisconsin. In addition, it is restricted from 

use in Del Norte and Humboldt Counties in California and Curry County, Oregon. Aldicarb can 

Aldicarb

Aldicarb Sulfone

Aldicarb Sulfoxide

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11 

only be applied between March 1 and September 1 in California. There are also restrictions on 

the use of aldicarb around drinking water wells. In all cases, application cannot be made within 

50 ft of a drinking water well, but more stringent conditions often apply. In most cases, these 

restrictions are based on the presence of a ‘vulnerable soil’ and the nature of the well. A 

vulnerable soil is defined on the label as having a loamy sand or sand texture and a subsoil with 

less than 2% organic matter on average in the upper 12 inches. Restrictions around the well are 

necessary if the water table is less than 25 ft deep, unless the well is cased to less than 100 ft or 

to 30 feet below the top of the water table. If the user does not know that the water table is 

greater than 25 feet, the applicator should assume a water table less than 25 feet deep. The 

following state and use restrictions depend upon the vulnerable soil and well descriptions. In 

Alabama, Georgia, Florida, and South Carolina, if a ‘split application’ is made (that is, one 

application at planting and a second side dress application is made after emergence), then there 

must be a 1100 ft buffer in place around drinking water wells. In these same states, a split 

application made to cotton with vulnerable soil and wells requires a 1000 ft buffer. If only a 

single application is made either at-plant or post-emergent then the wellhead buffer is 700 ft. For 

all uses in Iowa, Illinois, Indiana, Michigan, Minnesota, Montana, North Dakota, Nebraska, 

Ohio, South Dakota, and Wyoming, a 500 ft buffer is required around vulnerable wells in 

vulnerable soils. In these states, vulnerable soils are defined to include sandy loams, loamy sands 

and sands. In Colorado, Delaware, Kansas, Kentucky, Louisiana, Maryland, Missouri, 

Mississippi, North Carolina, Tennesee, Virginia, and West Virginia, a 300 ft buffer is required 

around vulnerable wells in vulnerable soils. For all other uses in Florida (other than peanuts and 

cotton) a 300 ft buffer is required around all drinking water wells. For all uses, applications 

cannot be made within 50 ft of any drinking water well. 

The Meymik label also has a number of precautionary label statements for the protection of 

wildlife and water resources. The statements for the protection of wildlife are: 

“This pesticide is extremely toxic to birds and other wildlife. Birds feeding on 

exposed granules may be killed. Cover or immedieately soil incorporate granules 

spilled during loading, at row ends, or elsewhere to ensure the granules are 

completely covered with soil. 

“This pesticide is toxic to fish and aquatic invertebrates. Run-off from treated 

areas may be hazardous to fish in neighboring areas. Do not apply directly to 

water, to areas where surface water is present or to intertidal area below the 

mean high water mark. Do not contaminate water when disposing equipment 

washwaters”. 

“This product is potentially toxic to honey bees through translocated residues in 

pollen and nectar if application is made during bloom.” 

There is also additional language regarding the Endangered Species Act: 

“Under the Endangered Species Act, it is a Federal Offense to use any pesticide 

in a manner that results in the death of a member of an endangered species.” 
12 

“This Act protects Attwater’s Prairie Chicken in the Texas counties of Aransas, 

Austin, Brazoria, Colorado, Galveston, Goliad, Harris, Refugio, and Victoria.” 

“Prior to making applications in these counties, the user must determine that this 

species is not located in or immediately adjacent to the area to be treated. If the 

user is in doubt whether or not the above named endangered species may be 

affected, he should contact either the regional U.S. Fish & Wildlife Service Office 

(Endangered Species Specialist) or personnel of the State Fish and Game Office.” 

Precautionary language for the protection of groundwater is: 

“Aldicarb is known to leach through soil into ground water under certain 

conditions. Use of this chemical in areas where soils are permeable, particularly 

where the water table is shallow, may result in ground water contamination. 

Apply this product only as specified on this label. Read the use directions and the 

appended Environmental Precautions and Soil Type Restrictions Tables prior to 

making applications.” 

“This product is readily decomposed to harmless residues under most use 

conditions. However, a combination of permeable and acidic soil conditions, 

moderate to heavy irrigation and/or rainfall, use of 20 or more pounds per acre, 

and soil temperatures below 50o F (10o C) at application time tend to reduce 

degradation and promote movement of residues into ground water.” 

Table 4-1 Labeled Aldicarb Use Pattern of Maximum Exposure1

. 

Use 

Max. Single 

App. Rate 

(lbs a.i./A) 

Max. No. of 

App. per Year

Min. Reapp. 

Interval (A)

Max. 

Annual 

App. Rate

(lbs a.i./A)

Application Method 

Peanuts4 1.5 2 NS2 2.55 

at-plant: incorporated band or 

T-band 

post-emergent: banded over 

foliage 

Cotton5 2.1 2 21 d 3.15 at-plant: in furrow and T-band

post-emergent: in furrow 

Sugar Beets6 4.95 3 NS 4.95 

at-plant: incorporated band 

post-emergent: incorporated 

side band 

Dry Beans7 2.1 1 NA3 2.1 at-plant: in furrow 

Soybeans8 1.05 1 NA 1.05 at-plant: T-band 

Sweet Potatoes9 3 1 NA 3 pre-plant or at-plant: band 

covered by hilling 

1) Additional language for ground water protection are discussed in the text. 
13 

2) NS: not specified 

3) NA: not applicable 

4) Post-emergent applications must be irrigated immediately after application. Post-emergent applications 

must be made to dry foliage. At-plant applications are restricted to 1.05 lb-ai/acre. Post-emergent 

applications are restricted to Alabama, Florida, Georgia, North Carolina, Oklahoma, Texas, and Virginia. 

5) Second application is restricted to 0.75 lb and must be placed in furrow at least 2 inches deep. Applications 

must be between March 1 and September 1 in California. 

6) Use on sugar beets is restricted to California, Colorado, Idaho, Montana, Nebraska, Oregon, Washington, 

and Wyoming. Applications must be made within 60 days of planting. 

7) Applications to dry beans are restricted to Colorado, Oregon, Washington, Idaho, and Michigan. 

8) Use on soybeans is restricted to Georgia, North Carolina, South Carolina, and Virginia. 

9) Use on sweet potatoes is restricted to Louisiana and Mississippi. Application must be made with positive 

displacement applicators. 

Cotton. There is a special local needs registration (24c) for aldicarb use on cotton in the state of 

California that allows up to 2.1 lb·acre-1 for a second side dress application and 3.15 lb·acre-1

total to be applied per year. For other states, the side dress application is limited to 0.75 lb·acre-1

and the maximum seasonal rate is 1.8 lb·acre-1. In either case, two applications can be made per 

season to cotton with the first application made at-plant, in-furrow with the requirement that the 

granules in the furrow be immediately covered with soil by mechanical means. Side dress 

applications are to be made 3 weeks after planting to first bloom (24c) or first squaring (Section 

3 label). Side dress applications are to be to a depth of 2 to 3 inches in a furrow 6 to 10 inches on 

one or both sides of the the row. The label restrictions include a note to deep-disk any spills at 

row ends or elsewhere to ensure the granules are covered with a layer of soil. Applications in 

California are restricted to between March 1 and September 1. Specific restrictions for 

applications to cotton around drinking water wells are discussed above. 

Dry Beans. While ‘dry beans’ can be used to describe a large number of legumes, in most cases 

it refers to the mature fruit of Phaseolus vulgaris, the common edible bean (e.g., kidney bean, 

red bean, black bean, navy bean, etc.). It does not include the use on the same crop when they are 

picked immature (e.g., green beans, wax beans, pole beans, or snap beans). The use of aldicarb 

on dry beans is restricted to Colorado, Oregon, Washington, Idaho, and Michigan. Only one 

application can be made per year at up to 2.1 lb·acre-1. Applications must be made at-plant either 

in the seed furrow or in a separate furrow 2 to 3 inches deep to the side of the seed furrow and 

covered with soil by mechanical means. The label restrictions include a note to immediately 

deep-disk any spills at row ends or elsewhere to ensure the granules are covered with a layer of 

soil. 

Peanuts. Either one or two applications of aldicarb can be made to peanuts. However, two 

applications and applications not made at planting can only be made in Alabama, Florida, 

Georgia, North Carolina, Oklahoma, Texas and Virginia. At-plant applications can be made 

either in-furrow or in a T-band over the open seed furrow. In either case the label states to cover 

immediately with soil by mechanical means. At-plant applications can also be made as a 6 to 12 

inch band which is mechanically incorporated from 2 to 4 inches in depth into which the peanuts 

are subsequently planted. Post-emergent applications are to be made at or just prior to peg 

initiation (when the peanuts start to enter the ground) but no later than 40 days after emergence 

and prior to the last cultivation. At-plant applications can be made at up to 1.05 lb·acre-1 while 

the maximum post-emergent application rate is 1.5 lb·acre-1. The seasonal maximum application 

is 2.55 lb·acre-1. A second application cannot be made to Spanish peanuts and other short-season 
14 

varieties that do not have at least 90 days between pegging and harvest. The label restrictions 

include a note to immediately deep-disk any spills at row ends or elsewhere to ensure the 

granules are covered with a layer of soil. 

Soybeans. Applications of aldicarb to soybeans can only be made in four states: Georgia, North 

Carolina, South Carolina, and Virginia. Only one application can be made per year at planting at 

1.5 lb·acre-1 for control of Mexican bean beetle, thrips, three-cornered alfalfa hopper and 

nematodes. Application can be made in-furrow or as a T-band 4 to 6 inches wide across the open 

seed furrow. In either case, the label says that the aldicarb must be immediately covered by 

mechanical means. The label restrictions include a note to immediately deep-disk any spills at 

row ends or elsewhere to ensure the granules are covered with a layer of soil. 

Figure 4-2. Estimated National Usage of Aldicarb from 1999 to 2002 (USGS, 2011). 

Sugar Beets. Applications of aldicarb to sugar beets can only be made in California, Colorado, 

Idaho, Montana, Nebraska, Oregon, Washington, and Wyoming. Applications in California can 

only be made between March 1 and September 1. The maximum annual application rate is 4.2 

lb·acre-1 in California and 4.95 lb·acre-1 in all other states. No more than three applications can be 
15 

made per year, one application at planting, and two post-emergent applications. The maximum 

single application rate at-plant is 2.1 lb·acre-1 in California and 4.95 lb·acre-1 in other states. The 

maximum single application rate for post-emergence applications is 2.1 lb·acre-1 in California 

and 3 lb·acre-1 in other states. For control of nematodes, applications can be made up to a week 

before planting in a band 4 to 6 inches wide which is immediately incorporated. Planting is then 

done into the incorporated band. Alternatively, the granules can be drilled in a row 3 to 4 inches 

deep and three inches to the side of the seed row if furrow irrigation is employed for seed 

germination. For aphid control, granules can be placed in the seedline if the application does not 

exceed 1.05 lb-ai·acre-1. Otherwise, the granules should be drilled 1 to 3 inches below the 

seedline. For sugar beet root maggot control, granules can be applied in a band 2 to 3 inches 

wide over the seed row and immediately incorporated, or, if furrow irrigation is employed for 

seed germination, granules can be drilled in a row 2 inches deep 2 inches from the seed furrow. 

Post-emergent applications are to be made on both sides of the plant row and immediately 

covered with soil or, if furrow irrigation is present, 4 to 8 inches on the water side of the plants at 

furrow depth. Post-emergent applications must be made within 30 days of planting in California 

and within 60 days of planting elsewhere. 

Sweet Potatoes. Applications of aldicarb to sweet potatoes can only be made in Louisiana and 

Mississippi. Only one application can be made at planting. Applications are restricted to 3 lbai·acre-1. Application are to be made in a 12 inch band over open furrow or on the soil surface 

and covered immediately during bed formation by mechanically hilling up to 8 to 10 inches. 

Transplants should be made in the center of the treated zone. 

The estimated use of aldicarb from 1999 to 2002 is in Figure 4-1. Note that a number of uses 

which were allowed in this period, namely citrus, pecans, and tobacco are no longer allowed on 

the label. The bulk of aldicarb use is concentrated along the south Atlantic Coastal Plain, the 

Mississippi Delta, Texas, California and the northwestern states. 

The Biological and Economic Analysis Division completed a review of aldicarb usage in 

December 2011 (Brassard et al.,2011). This assessment did not include any data for the sweet 

potato use. In the period 1998 to 2010 BEAD found that the total usage of aldicarb had not 

changed substantially, though the use on citrus increased in latter half of the 2000s. In the period 

of 2006 to 2010, the average use of aldicarb on all crops was 3.6 million pound on 3.7 million 

acres. In this period, the top crops were cotton (47%), oranges (23%), peanuts (13%), and 

potatoes (6%).The use on oranges and other citrus is no longer a registered use. In the same time 

period, the top states in terms of pounds applied are Florida (28%), Georgia (22%), and Texas 

(12%). 

4.3. Environmental Fate and Transport 

Aldicarb rapidly degrades to aldicarb sulfoxide and aldicarb sulfone – both of which are as toxic 

or nearly as toxic as, and are more persistent than, the parent compound. Other aldicarb 

degradates may form as well, but are substantially less toxic and/or produced only in small 

amounts (<5%) and so are not included in this evaluation. Aerobic soil metabolism is the primary 

dissipation route for parent aldicarb in unsaturated soil. Half-lives for parent aldicarb range from 

1 to 17 days (MRIDs 00102051, 00093642, 00080820, 00093640, 00053366, 00101934, 
16 

00035365, and 00102071). There is currently insufficient data to accurately estimate the 

formation and dissipation rates of the sulfoxide and sulfone degradates. However, the rapid 

oxidation of parent aldicarb to these forms and their substantially greater persistence than the 

parent, have been well documented in the published literature (e.g., Bull et al., 1970; Smelt et al., 

1979). 

Laboratory studies suggest that degradation of all three aldicarb forms (i.e., parent, sulfoxide, 

and sulfone) to relatively non-toxic, non-carbamate residues (oximes and nitriles) occurs slowly 

(t1/2 up to 3 months) in aerobic soils, as a result of soil-catalyzed hydrolysis rather than aerobic 

metabolism (Lightfoot et al., 1987; Bank and Tyrrell, 1984). Parent aldicarb is generally stable 

to hydrolysis, slowly hydrolyzing only at a pH of 9 (MRID 00102065). Aldicarb sulfoxide 

hydrolyzed more quickly (t1/2 = 2.3 days) at pH 9 than at pH 7 (about 6% at 28 days) (MRID 

00102066). Aqueous photolysis rapidly degraded aldicarb to oxime and nitrile forms (i.e. with a 

t1/2 of four days: MRID 42498201). However, this process will only be dominant in clear, 

shallow waters, and will not affect residues in the subsurface. 

While there is limited information on aerobic metabolism of aldicarb in aquatic environments, a 

published laboratory study (Vink et al., 1997) reported half-lives ranging from 70 to 173 days in 

surface waters in the Netherlands. The fate of parent aldicarb under anaerobic aquatic conditions 

(particularly ground water) is of less concern than that of the degradates (i.e., aldicarb sulfoxide 

and aldicarb sulfone), which have been detected in ground water long after application of the 

parent chemical had ceased. Published studies have reported increased degradation rates under 

low redox conditions, perhaps due to catalysis by reduced metal species in these environments 

(Bromilow et al., 1986). For example, Smelt et al. (1983) reported laboratory half-lives of 

aldicarb sulfone and sulfoxide ranging from 2 to 131 days in Dutch subsoils under “anaerobic 

conditions” (310 mV), and from 84 to 1100 days under aerobic conditions. Given this 

information, it is likely that aldicarb sulfoxide and aldicarb sulfone, which degrade relatively 

slowly in aerobic soil (MRID 44005001), can gradually leach into ground water and continue to 

provide detectable levels of these materials over long time periods. 

In published field studies, dissipation half-lives for total carbamate residues in soil have ranged 

from approximately 0.3 to 5 months in the unsaturated zone, and 1 to 36 months in the saturated 

zone (Jones and Estes, 1995), in apparent contradiction to the observation of faster degradation 

under anaerobic (saturated) conditions reported above (Smelt et al.,1983). The reasons for the 

extreme variability in reported transformation rates (3 hours to 36 months) for aldicarb residues 

under anaerobic/saturated conditions are uncertain, but may be related to temperature, pH, and 

the presence of soils surface catalysts (Lightfoot, et al., 1987). Also, not all saturated zones are 

necessarily anoxic; if they are shallow, there can be sufficient interaction with the unsaturated 

zone such that the ground water may be sub-oxic or even atmosphere-equilibrated (oxic). 

Monitoring data in areas with historical aldicarb contamination confirm the high persistence of 

total aldicarb residues in some ground water. For example, twenty years after cessation of 

aldicarb use on Long Island, New York, aldicarb sulfone and sulfoxide were the most frequently 

detected pesticide compounds in ground water there in year 2000 (Suffolk County Dept. of 

Health Services, 2000). 

The sulfoxide and sulfone degradates are nearly as mobile as the parent and are more persistent. 

They are generally of lower toxicity than the parent, although the sulfoxide is approximately the 
17 

same toxicity to aquatic invertebrates (See 5.35.3). For aquatic exposures the parent aldicarb may 

undergo some transformation to the sulfoxide and sulfone residues between the time of 

application to the soil and a runoff event. A selection of environmental fate and transport 

properties of aldicarb are summarized in Table 4.2. 

Table 4.2. General Physical/Chemical Properties and Environmental Fate Parameters of 

Aldicarb. 

Parameter Value Reference

Physical/Chemical Parameters

Molecular mass 190.26 g/mol calculated

Vapor pressure (23°C) 6.25 x 10-6 torr MRID 4822504

Henry’s Law constant (23°C) 3.0 x 10-10 atm·m3/mol calculated

Water solubility (20°C) 5.191g/L MRID 4822504

Octanol-water partition coefficient 

( KOW)

11.48 MRID 4822504

Persistence in Water

Hydrolysis half-life pH 5: no significant degradation @ 30 d 

pH 7: no significant degradation @ 30 d 

pH 9: < 10% degradation of parent @ 30 d 

 T1/2 < 197 d 

MRID 00102065

Aqueous photolysis half-life 4 d MRID 42498201

Persistence in Soil

Aerobic soil metabolism half-life parent only: 

 NJ sandy loam: 2.3 d 

 Houston clay: 11 d 

 Lakeland sandy loam: 17 d 

 Norwood silty clay: 12 d 

 unspecified: 1 d 

 Illinois silt: 6 d 

 NC loamy sand: 10 d 

total toxic residues: 

 Houston clay: 28 d 

 Lakeland sandy loam: 47 d 

 Norwood silty clay: 136 d 

 unspecified: 44 d 

MRID 44005001 

MRID 00093642 

MRID 45602904 

MRID 45739801 

MRID 00093642 

MRID 45602904 
18 

Parameter Value Reference

Mobility

Fruendlich Adsorption 

Coefficients (Kf) 

parent 

 sandy loam: 0.18 6 L·kg-1

 silt: 0.36 L·kg-1

 clay: 0.6 L·kg-1

 sand: 0.2 L·kg-1

aldicarb sulfoxide:

 Tujunga loamy sand: 0.22 L·kg-1

 Wedowee sandy loam: 0.17 L·kg-1

 Huntington silt loam: 0.26 L·kg-1

 Huntington sandy clay loam: 0.26 L·kg-1

aldicarb sulfone:

 Tujunga loamy sand: 0.09 L·kg-1

 Wedowee sandy loam: 0.12 L·kg-1

 Huntington silt loam: 0.22 L·kg-1

 Huntington sandy clay loam: 0.22 L·kg-1

MRID 42498202 

MRID 43560301 

MRID 43560302 

Parent aldicarb and its degradates are higly mobile and are known to move to ground water in 

sandy acidic soils. In poorly permeable soils, it will move with runoff. Following a rain event, 

aldicarb may reach aquatic environments as sheet and channel flow from areas of application, 

since aldicarb is moderately persistent in terrestrial environments and soluble in water. It is 

unlikely, though, that undissolved granules will reach surface water bodies as the granules 

themselves are not particularly mobile and in most cases buried below the surface. The toxic 

degradates (aldicarb sulfoxide and aldicarb sulfone) are more prone to move vertically down 

through the soil profile, and potentially into ground water, as they form primarily in the shallow 

subsurface. Ground water that contains aldicarb residues may then be discharged into surface 

waters as baseflow. If the receiving ground water is cool, acidic, and oxic, the sulfoxide and 

sulfone degradates will be very persistent and capable of long-distance subsurface transport. 

Aldicarb and its oxidation products are all highly mobile in soil. Aldicarb itself has Freundlich 

Kads values ranging between 0.19 ml/g (for sandy loam) and 0.60 ml/g (for clay) (MRID 

42498202). Aldicarb sulfoxide has Freundlich Kads values between 0.17 ml/g (sandy loam soil) 

and 0.26 ml/g (sandy clay loam) (MRID 43560301). Aldicarb sulfone had slightly lower values, 

ranging between 0.09 ml/g and 0.22 ml/g for the same set of soils as the sulfoxide (MRID 

43560302). Aldicarb is not expected to be mobile into or through the atmosphere because 

aldicarb is applied as a granule, and because its potential to enter the air from water or soil is 

considered insignificant based on its Henry’s Law constant (3.0 x 10-10 atm·m3

/mol) and vapor 

pressure (6.25 x 10-6 torr). 

In 2006, Bayer CropScience, submitted 5 retrospective ground water monitoring studies to look 

for residues of aldicarb and its sulfoxide and sulfone metabolites in potable water from private 

wells in aldicarb use areas. This study monitored 1,673 drinking water wells and collected 

information on ground-water depth, well depth, casing depth, well type and age, soil types, 

recent aldicarb use history, crops, and distance of the well from the treated field. The study 

sampled drinking water wells in five regions of the country: the Southeastern US (800 wells), the 
19 

Mississippi Delta (169 wells), the Pacific Northwest (303 wells), Texas (201 wells), and 

California (200 wells). The study found that aldicarb residues – predominantly the sulfoxide and 

sulfone metabolites – were detected in 10 percent of the wells sampled. The greatest frequencies 

of detections were in the Southeastern US (16%, with a maximum detect of 2.9 ug/L) and the 

Mississippi Delta (9%, with a maximum detect of 2.6 ug/L) regions. Because the single samples 

represent a snapshot in time, the Agency assumed that the measured concentrations reflected a 

median concentration for that particular well. Frequency and magnitudes of detection for 

aldicarb residues were generally greater for wells located within 300 feet of a field (~10% of 

wells had detections); aldicarb residues were detected in 4-6% of wells located >300 feet from 

the field, although detections were < 1ug/L. A comparison of wells located near fields with 

restricted soils (as identified in the Temik 15G label) to those where the surrounding fields 

contained no restricted soils showed that, while the frequency of aldicarb detections was greater 

for wells near restricted soil types, the magnitude of aldicarb residues was greater for wells with 

no restricted soil types. 
20 

5. Receptors 

Consistent with the process described in the Overview Document (USEPA, 2004), the risk 

assessment for aldicarb will rely on a surrogate species approach. Toxicological data generated 

from surrogate test species, which are intended to be representative of broad taxonomic groups, 

are used to extrapolate to potential effects on a variety of species (receptors) included under 

these taxonomic groupings. 

The Agency evaluates the potential for adverse affects as a result of aldicarb usage. As 

described in the Agency’s Overview Document (USEPA, 2004), the most sensitive endpoint for 

each taxon is used for RQ calculations. Assessment endpoints include direct toxic effects on the 

survival, reproduction, and growth of terrestrial and aquatic life, as well as indirect effects, such 

as reduction in prey base and/or modification of habitat. The evaluated taxa include freshwater 

fish, freshwater aquatic invertebrates, birds, small mammals, terrestrial invertebrates, algae, and 

terrestrial plants. 

Acute (short-term) and chronic (long-term) toxicity information is characterized based on 

registrant-submitted studies and a comprehensive review of the open literature on aldicarb. 

Other sources of information, including use of the acute probit dose response relationship to 

establish the probability of an individual effect and reviews of the Ecological Incident 

Information System (EIIS), are conducted to further refine the characterization of potential 

ecological effects associated with exposure to aldicarb. A summary of the available ecotoxicity 

information and the incident information for aldicarb is provided below. 

Table 5.1 provides a summary of the assessment endpoints previously identified as a measure of 

effects. A detailed summary of available toxicity data is provided in the Appendix. 

Table 5.1 Measures of Ecological Effects for Aldicarb 

Assessment Endpoint Selected Surrogate Species and Measure of Ecological 

Effect Comments 

Birds Survival Mallard duck oral LD50 = 1 mg ai/kg-bw MRID 00107398 

Survival 

Mallard duck subacute dietary LC50 = 594 ppm 

Bobwhite quail subacute dietary LC50 = 71 ppm 

MRID 1096727 

MRID 00102132 

Reproduction 

and growth 

Mallard duck NOAEC/LOAEC = not established 

Bobwhite quail NOAEC = 1.8 ppm, LOAEL = 8.3 ppm 

MRID 48198801 

MRID 48156905 

Mammals Survival Rat LD50 = 0.9 mg ai/kg bw MRID 00057333 

Reproduction 

and growth 

Rat NOAEL = 0.4 ppm MRID 42148401 

Freshwater fish Survival Rainbow trout acute 96-hr LC50 = 0.560 ppm ai 

Bluegill sunfish 96-hr LC50 = 0.052 ppm ai 

MRID 40098001 

MRID 40098001 

Reproduction 

and growth 

Fathead minnow NOAEC = 0.078 ppm; LOAEC = 0.156 

ppm 

MRID 44598601 

Freshwater 

invertebrates 

Survival Chironomus acute 48-hr EC50 = 0.020 ppm ai Moore et al.

1998 

Reproduction 

and growth 

Daphnia NOAEC = 0.020 ppm ai; LOAEC = 0.058 ppm 

ai 

MRID 45592112 
21 

Assessment Endpoint Selected Surrogate Species and Measure of Ecological 

Effect Comments 

Estuarine/marine 

fish 

Survival Sheepshead minnow LC50 = 0.041 ppm ai MRID 40228401 

Reproduction 

and growth 

Sheepshead minnow NOAEC =0.05 ppm; LOAEC = 0.088 

ppm 

MRID 00066341

Estuarine/marine 

invertebrates 

Survival Pink shrimp LC50 = 0.012 ppm ai 

Oyster 96-hr EC50 = 8.8 ppm ai 

MRID 40228401 

MRID 00066341 

Reproduction 

and growth 

Mysid NOAEC = 0.0013 ppm MRID 00066341 

Terrestrial plants Survival and 

growth 

Seedling Emergence: >25% effects observed in ryegrass 

(shoot weight) and tomato (shoot length and weight) 

Vegetative Vigor: No data but prior waiver was granted 

MRID 47904401 

Insects Survival Acute contact LD50 = 0.285 ug/bee MRID 00036935 

Aquatic plants Biomass and 

Growth Rate 

7 day Duckweed EC50 > 88.7 ppm ai; NOAEC = 5.50 

ppm 

5 day Marine Diatom EC50 > 50 ppm ai 

MRID 47904402 

MRID 40228401 

LD50 = Lethal dose to 50% of the test population; NOAEC = No observed adverse effect concentration; NOAEL = 

No observed adverse effect level; LC50 = Lethal concentration to 50% of the test population; EC50 = Effect 

concentration to 50% of the test population; IC50= concentration resulting in a 50% inhibition in the test population 

response (e.g., growth) 

5.1. Effects to Terrestrial Species 

5.1.1. Birds and Mammals 

The acute oral LD50 is 1.0 mg/kg-bw for aldicarb and 33.5 mg/kg-bw for aldicarb sulfone. The 

most sensitive species tested for both chemicals is the mallard duck. Aldicarb and aldicarb 

sulfone are categorized as very highly toxic and highly toxic to avian species on an acute oral 

basis, respectively (MRID 107398). 

The most sensitive species tested on a subacute 5-d dietary basis for both aldicarb and aldicarb 

sulfone is the bobwhite quail. The LC50 is 71 ppm for aldicarb and 5706 ppm for aldicarb 

sulfone. Aldicarb and aldicarb sulfone are categorized as very highly toxic and practically nontoxic to avian species, respectively, based on the subacute dietary exposure data (MRID 

00102132 & 1096727). 

Avian reproduction data suggests that Aldicarb has reproductive effects at 8.3 ppm with a 

NOAEC of 1.8 ppm (MRID 48198801). Although none of the endpoints in the treated groups 

displayed statistically significant differences compared to controls, several of the endpoints had 

10-25% difference in the two highest treatments. These endpoints include: number of eggs 

laid/pen, number of eggs set/pen, number of viable embryos/pen, number of live embryos/pen, 

number of hatchlings/pen, hatchling survival/pen. In addition, adult body weight gain was also 

decreased in these treatments. These differences may be biologically significant. Therefore, the 

NOAEC was 1.8 ppm and the LOAEC was 8.3 ppm. 
22 

Acute oral LD50 and reproduction data for laboratory rats submitted to the Health Effects 

Division (HED) for evaluation of human toxicity were used to assess the mammalian acute and 

chronic toxicity of aldicarb. The LD50 for rats is 0.9 mg ai/kg (MRID 00057333). These results 

classify aldicarb as very highly toxic to mammals on an acute exposure basis. In a 2-generation 

reproduction study (MRID 42148401), rats were exposed to aldicarb in their diet at 

concentrations of 0, 2, 5, 10, and 20 ppm. Exposure consistently led to decreased dam body 

weight gain (parental LOAEL = 0.7 - 0.9 mg/kg-bw; NOAEL = 0.4 mg/kg-bw). Aldicarb 

treatment also caused lower survivability and pup weights in offspring of all litters (reproductive 

LOAEL = 1.4 - 1.7 mg/kg-bw; NOAEL = 0.7 - 0.9 mg/kg-bw). These toxicity values are similar 

to the acute oral LD50 mammalian values and suggest that mammals that survive acute aldicarb 

exposure may suffer adverse reproductive effects from chronic exposure. 

5.1.2. Beneficial Insects 

An acute contact study using aldicarb resulted in an LD50 of 0.285 μg/bee and the compound was 

classified as very highly toxic (MRID 00036935). Because of its granular formulation, it is 

unlikely that there is a direct contact exposure scenario for honeybees. Other soil dwelling 

beneficial insects and invertebrates could be exposed to aldicarb and aldicarb residues through 

contact with the granules and/or with plants due to its systemic nature. 

5.1.3. Plants 

A seedling emergence study was submitted (MRID 47904401) but was classified as 

supplemental. The most sensitive monocot species was ryegrass, with a 12 and 44% difference 

in shoot length and weight, respectively, compared to the control. The most sensitive dicot 

species was tomato, with a 28 and 25% difference in shoot length and weight, respectively, 

compared to the control. Phytotoxic effects, including stunting and necrosis, were observed in 

ryegrass and tomatoes. Based on the observance of >25% effects in ryegrass and tomato, a tier II 

study with these two species is necessary to fulfill the guideline requirement for 850.4100. A 

vegetative vigor study was not available since a waiver was previously granted for it. 

5.2. Effects to Aquatic Species 

5.2.1. Parent Aldicarb Toxicity 

5.2.1.1. Fish 

Acute Exposure 

Since the LC50 falls in the range of 52 to 8860 ppb, aldicarb is categorized as very highly to 

moderately toxic to freshwater fish on an acute basis. The most sensitive freshwater fish species 

tested for aldicarb was the bluegill sunfish. The LC50 for aldicarb was 52 ppb for the bluegill 

sunfish which is characterized as very highly toxic to freshwater fish [MRID 40098001 and 

MRID 3503 (Mayer and Ellersieck 1986)]. This same study found n LC50 of 560 ppb for the 

rainbow trout. A supplemental acute toxicity test conducted under static conditions found an 

LC50 for aldicarb of 110 ppb for juvenile bluegill sunfish. Because of the static conditions, it is 

likely this value reflects contribution of parent aldicarb and its degradates. This study 
23 

characterized aldicarb as very highly toxic to juvenile bluegill sunfish. A supplemental study 

from the open literature also concluded that aldicarb was moderately toxic to the fathead minnow

Pimephales promelas with a reported 48-hour EC50 of 8860 ppb (Moore. et al. 1998). The LC50

of 52 ppb for the bluegill sunfish was used to calculate risk quotients in prior assessments 

because it was the most sensitive endpoint. 

Chronic Exposure 

A freshwater fish early life-stage test using aldicarb has been conducted with the fathead 

minnow. The NOAEC was 78 ppb, the LOAEC was 156 ppb. The most sensitive endpoint was 

the survival of juveniles after 30-days exposure. [MRID 44598601 also identified as 

BOWOAL07/4 (Q.H. Pickering and W.T. Gilliam 1982)]. 

A saltwater fish chronic study was conducted using the sheepshead minnow (MRID 00066341). 

The NOAEC was 50 ppb, the LOAEC was 88 ppb. The most sensitive endpoint was growth 

(mean standard length). 

5.2.1.2. Aquatic Invertebrates 

Acute Exposure 

A Daphnia magna acceptable study determined the EC50 to be 410 ppb (Acc #096683, also 

identified as BOWOAL08, and MRID 107395), categorizing aldicarb as highly toxic to aquatic 

freshwater invertebrates on an acute exposure basis. Because this test was conducted under 

static rather than flow-through conditions, it is likely that this value reflects the contributions of a 

mixture of parent aldicarb and various degradates. A supplemental study from the literature 

reported the LC50 of aldicarb to Daphnia magna, Aedes aegypti, Atermia sp., and Aedes 

taeniorhynchus as 75, 290, 5460, and 150 ppb respectively, in 48-hour static tests (Song et al., 

1997). A supplemental study from open literature also concluded that aldicarb was very-highly 

toxic to Daphnia magna with a reported 48-hour EC50 was of 583 ppb (Moore et al. 1998). This 

same study reported a 48-hour EC50 of 3990 ppb for Hyalella azteca (categorized as moderately 

toxic) and a reported 48-hour EC50 of 20 ppb for Chironomus dilutus (formerly known as C. 

tentans). A supplemental study obtained from open literature (Foran et al. 1985) determined the 

48-hr EC50 of juvenile Daphnia laevis to be 65 ppb and 51 ppb for adult Daphnia laevis

categorizing aldicarb as very highly toxic. Because Moore et al. (1998) is classified as a 

supplemental study of high quality, the 48-hr Chironomus dilutus EC50 value of 20 ppb was used 

in prior risk characterizations. 

Because Moore et al. (1998) is classified as a supplemental study of high quality, the 48 hr 

Chironomus tetans EC50 value of 20 ppb was used in prior risk characterizations. 

Chronic Exposure 

A chronic estuarine/marine invertebrate full life-cycle test using aldicarb has been conducted 

with mysid shrimp. The NOAEC was 1 ppb and the LOAEC was 1.5 ppb. The most sensitive 

endpoint was average number of offspring (MRID 00066341). 
24 

5.2.1.3. Aquatic Plants 

A 7-day acute toxicity study with Duckweed (Lemna gibba) resulted in a LC50 of >88.7 mg ai/L 

(the highest concentration). The NOAEC was 5.50 mg ai/L based on effects to frond number, 

biomass and dry weight at the LOAEC of 14.3 mg ai/L (MRID 47904402). A 5 day study with 

the diatom produced an EC50 of >50 ppm (MRID 40228401). 

5.3. Degradate Toxicity 

Aldicarb’s sulfone and sulfoxide degradates have been shown to be 1 to 2 orders of magnitude 

less toxic compared with parent aldicarb to aquatic organisms. For more detailed information 

see the Appendix. 

5.4. Incident Database Review 

A search was made on October 27, 2011 of the Ecological Incident Information System (EIIS, 

version 2.1), which is maintained by the Agency’s Office of Pesticide Programs, and the Avian 

Incident Montoring System (AIMS), which is maintained by the American Bird Conservancy. A 

total of 36 incidents for aldicarb were reported to the Agency. There were 17 (47%) incidents 

(most using WDG bait applications) classified as “highly probable” of which 15 were classified 

as “intentional misuse”, 1 was classified as “accidental misuse” and another was classified as 

“unknown”. There were 9 (25%) incidents classified as “probable”, 10 (28%) classified as 

“possible” and 0 classified as “unlikely”. The following table summarizes these incidents. 
25 

Table 5.2. Summary of Aldicarb Incidents Incident # Date County State Certainty Legality Formulation Appl 

Method 

Total Magnitu

AQUATIC Agricultural Area I000165-052 6/12/92 NC 2 RU WDG Soil Incorp. Sm Number oN/R I003826-002 6/12/95 Johnston NC 2 UN N/R N/R Unknown PLANTS Cotton I010837-012 5/18/00 Williamsburg SC 2 UN 655 acres of 6Peanut I011838-085 Caddo OK 2 UN 106 acres I011838-010 5/27/00 Houston GA 2 UN N/R N/R All 141 acres I011838-061 5/21/01 Caddo OK 2 UN 217 acres I011838-059 5/21/01 Caddo OK 2 UN 78 acrea Potato I012089-009 8/7/01 Bingham ID 2 RU N/R Pre-Broadcast All 1050 acres TERRESTRIAL Agricultural Area I001267-001 10/3/94 4 MI WDG Unknown 1 Hawk I010439-001 6/1/00 Pearl River MS 4 MI N/R Bait 1 Coyote & 1 I013168-001 7/25/02 Carroll TN 4 MI Bait 9 birds I021411-012 10/29/0

8 

Eastland TX 3 M WDG Animal control 

Device 

1 Hawk & 1 B

Bait I002352-001 4/9/92 Edgefield SC 4 MI WDG Bait 3 Hawks, 1 Ra

1 Opossum, 1 & a number of 

I008694-001 2/10/98 Marengo AL 2 MI WDG Bait 1 Golden EaglI007595-001 7/15/98 Evangeline LA 3 MA WDG Bait 1 Raccoon I011213-007 2/28/01 VA 3 MI WDG Bait 1 Great horned I016407-062 5/15/05 ID 4 MI Bait 1 Gray Wolf I017085-001 3/1/06 Floyd GA 4 MI Bait 1 Dog & 2 OpI019925-001 2/23/08 Hancock GA 4 MI WDG Bait 1 Coyote, 1 R

Hawk & 23 ot
26 

Table 5.2. Summary of Aldicarb Incidents Bait, carcass/meat B000178-001 12/1/88 NE 4 UN 3 Magpie & 1 I010439-002 7/1/00 Hancock MS 3 MI N/R Bait 1 Dog, 1 Racc

1 Buzzard 

I013928-001 2/7/03 Columbia GA 4 MI Bait 1 Coyote, 1 R

1 Yellow-rum

I017141-001 1/3/06 Floyd GA 2 MI 2 Dogs & 2 OI019363-003 1/29/08 Pike AL 3 MI WDG Bait 2 Dogs & 3 OI019647-014 2/12/08 MS 4 MI WDG Bait 10 Hawks & s

Vultures 

I019647-015 2/27/08 Montgomery AR 4 MI WDG Bait 30-35 I019647-016 3/24/08 McDuffie GA 4 MI Bait 20-25 Cotton I005364-001 Mississippi AR 4 MA Soil incorp 2 Dogs & 1 RN/R I011300-001 2/7/01 Putnum GA 4 MI Bait 2 Hawks I014343-001 7/9/03 Effingham GA 3 UN 2 Vultures I017462-001 3/27/06 Troup GA 4 MI 2 Vultures & Potato B0000-400-7 3/17/91 Hertford NC 4 MI Unincorp 

Broadcast 

24 Gulls, 2 FinBlackbirds 

I000799-005 3/18/91 Hertford NC 3 MI WDG N/R 37 Quarry I015916-001 1/1/99 3 MI Bait 3 Peregrine FaRangeland I000637-001 1/1/93 Uvalde TX 3 MI N/R N/R Woodlands I007372-003 1/27/97 Kent DE 4 MI N/R N/R 1 Dog, 1 Red 

Red-tailed haw

MI= Intentional Misuse UN= unknown MA= Accidental Misuse 
27 

6. Ecosystems Potentially at Risk 

The ecosystems potentially at risk are often extensive in scope; therefore, it may not be possible 

to identify specific ecosystems during the development of a nation-wide ecological risk 

assessment. However, in general terms, terrestrial ecosystems potentially at risk could include 

the treated field and immediately adjacent areas that may receive drift or runoff. Areas adjacent 

to the treated field could include cultivated fields, fencerows and hedgerows, meadows, fallow 

fields or grasslands, woodlands, riparian habitats, and other uncultivated areas. 

Aquatic ecosystems potentially at risk include water bodies adjacent to, or down stream from, the 

treated field and might include impounded water bodies such as ponds, lakes and reservoirs, or 

flowing waterways such as streams or rivers. For uses in coastal areas, aquatic habitat also 

includes marine ecosystems, including estuaries. 

7. Assessment Endpoints 

Assessment endpoints represent the actual environmental value that is to be protected, defined by 

an ecological entity (species, community, or other entity) and its attribute or characteristics 

(USEPA, 1998). For aldicarb, the ecological entities include the following: birds, reptiles, 

terrestrial-phase amphibians, mammals, freshwater fish, freshwater aquatic-phase amphibians 

and invertebrates, estuarine/marine fish and invertebrates, terrestrial plants, insects, aquatic 

plants, and algae. The attributes for each of these entities include growth, reproduction, and 

survival. The assessment endpoints and their associated measures of effect that will be included 

in ecological risk assessments of aldicarb are included in Table 7.1. 

 Table 7.1 Summary of assessment endpoints and their measures of effects.

Assessment Endpoint Measures of Effect 

1. Abundance (i.e., survival, 

reproduction, and growth) of 

individual birds 

● Avian (at least mallard duck) acute oral (single dose) LD50

● Avian (at least mallard duck and bobwhite quail) subacute 5-day dietary 

LC50

● Avian (at least mallard duck) reproduction NOAEL (e.g., number of eggs 

laid, set, cracked, hatched; number of viable embryos; 14 day hatchling 

survival and growth; egg thickness; parental survival and weight gain/loss) 

2. Abundance (i.e., survival, 

reproduction, and growth) of 

individual mammal 

● Mammal (at least laboratory rat) acute oral (single dose) LD50 (male and 

female) 

● Mammal (at least laboratory rat) chronic (reproductive) NOAEC or 

NOAEL 

3. Survival and reproduction of 

freshwater fish and invertebrates 

● Fish (at least rainbow trout and bluegill sunfish) acute 96-h LC50

● Fish (at least rainbow trout or bluegill sunfish, prefer species tested match 

that of the more acutely sensitive species tested) chronic early life stage or 

life-cycle NOAEC (e.g., number hatched, time to hatch, mortality, growth of 

young) 

● Invertebrate (at least Daphnia magna) acute 96-h (48-h for cladocerans like 

D. magna) LC50 or EC50 where the effect measured is a surrogate for death 

● Invertebrate (at least Daphnia magna) chronic reproductive NOAEC (e.g., 

number of young produced, time to first brood release, parental survival, 

parental growth) 

4. Survival and reproduction of 

estuarine/marine fish and 

invertebrates 

● Fish (at least Atlantic silverside or sheepshead minnow) acute 96-h LC50

● Mollusk (at least Eastern oyster) acute 96-h EC50 where the effect 

measured is shell deposition or embryo/larval fertilization, survival, and 
28 

Assessment Endpoint Measures of Effect 

 normal shell development 

● Other invertebrates (at least pink shrimp or mysid shrimp) acute 96-h LC50

or C50 where the effect measured is a surrogate for mortality 

● Fish (prefer species that matches the most acutely sensitive fish tested) 

early life stage or life cycle NOAEC (e.g., number hatched, time to hatch, 

growth of young, overall survival) 

● Invertebrate (at least mysid shrimp, prefer species tested is the more 

acutely sensitive species tested) chronic NOAEC 

5. Perpetuation of individuals 

and populations of non-target 

terrestrial plants (crops and noncrop plant species) 

● Monocot and dicot seedling emergence EC25

● Monocot and dicot seedling emergence EC05 or NOAEC 

● Monocot and dicot vegetative vigor EC25

● Monocot and dicot vegetative vigor EC05 or NOAEC 

6. Survival of beneficial insects ● Honeybee acute contact LD50

7. Maintenance and growth of 

aquatic plants from standing 

crop or biomass 

● Aquatic plants (at least an algae (green, and blue-green), a diatom and a 

vascular plant (at least duckweed)) acute EC50

● Aquatic plants (at least an algae (green and blue-green), a diatom, and a 

vascular plant (at least duckweed)) EC05 or NOAEC 

LD50 = median lethal dose (mg/kg-bw/d) is the dose that results in 50% mortality of an exposed test population. 

NOAEC = No observed adverse effect concentration. 

LOAEC = Lowest observed adverse effect concentration. 

LC50 = median lethal concentration is the concentration that results in 50% mortality of an exposed test population. 

EC50 = median effect concentration is the concentration that results in a specific effect (e.g., immobility, emergence) 

to 50% of the exposed test population. 

EC25 = the concentration that results in a specific effect to 25% of the exposed test population. 

8. Conceptual Model 

For a pesticide to pose an ecological risk, it must reach ecological receptors in biologically 

significant concentrations. An exposure pathway is the means by which a pesticide moves in the 

environment from a source to an ecological receptor. For an ecological 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. 

The conceptual model for aldicarb provides a written description and visual representation of the 

predicted relationships between aldicarb, potential routes of exposure, and the predicted effects 

for the assessment endpoint. A conceptual model consists of two major components: risk 

hypothesis and a conceptual diagram (USEPA, 1998). 

Based on an examination of the physical/chemical properties of aldicarb, its fate and disposition 

in the environment, and its mode of application, a conceptual model was developed that 

represents the possible relationships between this pesticide as a stressor, ecological receptors, 

and the assessment endpoints. The conceptual model depicts the potential pathways for 

ecological risk associated with aldicarb use (see Figures 8.1 and 8.2). The conceptual model 

provides an overview of the expected exposure pathways and effects of aldicarb on terrestrial 

and aquatic environments. Solid arrows depict the most likely routes of exposure and effects; 

dashed lines depict potential routes of exposure that are not considered likely for aldicarb. 
29 

Figure 8-1. Conceptual model for aldicarb effects on aquatic organisms. Dotted lines 

indicate exposure pathways that have a low likelihood of contributing to ecological risk.

Based on the the use patterns, which are all granular, no off-site spray drift is expected to occur 

for aldicarb. Because aldicarb is not volatile with a vapor pressure of (6.25 x 10-6 torr) transport 

through the atmosphere is also unlikely to occur. While aldicarb and its degradates are known to 

contaminate ground water and it is possible that base flow from ground water into streams may 

contain aldicarb residues. Aldicarb residues in water from runoff are expected to be higher and 

assessment of concentrations from surface runoff will be used to be protective of risks due to 

base flow from ground water. Because aldicarb is highly soluble and poorly sorbed on soil 

particles, concentrations of aldicarb in puddles that may occur after rainfall or an irrigation event 

may be a significant route of exposure and will be assessed for risks to terrestrial mammals and 

birds. 

8.1. Risk Hypothesis 

A risk hypothesis describes the predicted relationship among the stressor, exposure, and 

assessment endpoint response along with the rationale for their selection. For aldicarb, the 

Stressor 

Source

Receptors 

Attribute 

Change 

Aldicarb applied to use site as granule 

Fish/aquatic-phase 

amphibians 

Eggs 

Larvae 

Juveniles / Adults 

Individual organisms 

Reduced survival 

Reduced growth 

Reduced reproduction 

Food chain 

Reduction in algae 

Reduction in prey 

Habitat integrity 

Reduction in primary productivity

Reduced cover 

Community change 

Surface water/ 

Sediment 

Runoff 

Aquatic Animals 

Invertebrates 

Vertebrates 

Exposure 

Media 

Uptake/gills 

or integument 

Ingestion Ingestion

Soil Groundwater 

Uptake/gills 

or integument 

Aquatic Plants 

Non-vascular 

Vascular 

Uptake/cell, 

roots, leaves Riparian plant

terrestrial 

exposure 

pathways see 

Figure 2 
30 

following ecological risk hypothesis is being employed for this national-level ecological risk 

assessment: 

Aldicarb, when used in accordance with current labels, can result in off-site 

movement of the compound to surface water via runoff, leaching to ground water, 

or exposure to terrestrial plants and animals. Exposure in these environmental 

compartments will result in adverse effects upon the survival, growth, and 

reproduction of non-target terrestrial and aquatic organisms. These non-target 

organisms include federally-listed threatened and endangered species. 

Figure 8-2. Conceptual model for aldicarb effects on terrestrial organisms.

9. Analysis Plan 

In order to address the risk hypothesis, the potential for adverse effects on the environment is 

estimated. The use, environmental fate, and ecological effects of aldicarb are characterized and 

integrated to assess the risks. This is accomplished using a risk quotient (ratio of exposure 

concentration to effects concentration) approach. Although risk is often defined as the likelihood 

and magnitude of adverse ecological effects, the risk quotient-based approach does not provide a 

quantitative estimate of likelihood and/or magnitude of an adverse effect. However, after 

calculating the risk quotient values, the likelihood of effects to individual organisms from 

Stressor 

Source

Receptors 

Attribute 

Change 

Aldicarb applied to use site as granule 

Direct 

application 

Birds / Terrestrialphase amphibians 

/ reptiles / 

mammals 

Terrestrial 

insects 

Individual organisms 

Reduced survival 

Reduced growth 

Reduced reproduction 

Food chain 

Reduction in prey 

Habitat integrity 

Reduction in primary productivity

Reduced cover 

Community change 

Terrestrial/riparian plants 

grasses/forbs, fruit, seeds 

(trees, shrubs) 

Atmosphere 

Mammals

Exposure 

Media 

Soil 

Ingestion 

Ingestion

Ingestion

Ingestion

Dermal uptake/Ingestion 

Root uptake 

Birds / 

Amphibians 

Ingestion 

Runoff 
31 

particular uses of aldicarb is estimated using the probit dose-response slope and either the level 

of concern (discussed below) or actual calculated risk quotient value (USEPA, 2004). 

This analysis plan will be revisited and may be revised depending upon the information 

submitted by the public in response to the opening of the registration review docket for aldicarb. 

9.1. Measures of Exposure 

In order to estimate risks of aldicarb exposures in aquatic and terrestrial environments, all 

exposure modeling and resulting risk conclusions will be based on maximum application rates 

and methods and will be estimated for each use of aldicarb. Measures of exposure are based on 

aquatic and terrestrial models that predict estimated environmental concentrations (EEC) of 

aldicarb residues of concern. 

Because levels of concern to aquatic organisms have been exceeded in previous assessments, the 

aquatic exposure assessment will be performed at Tier 2. The models used to predict aquatic 

EECs are PRZM and EXAMS – PRZM is used to model processes on the agricultural field and 

generates inputs for EXAMS which simulates processes in the waterbody. The model used to 

predict screening level (Tier 1) terrestrial EECs is the Terrestrial Residue EXposure (T-REX) 

model. The model used to derive screening level EECs relevant to terrestrial and wetland plants 

is TerrPlant. These models are parameterized using relevant reviewed environmental fate data 

from registrant submissions and the literature; model input values will be consistent with the 

most recent version of the input parameter guidance (USEPA, 2009). 

The measure of exposure for aquatic species is the modeled peak or rolling mean concentration 

which recurs once every ten years. The 1-in-10 year peak concentration is used for estimating 

acute exposures of direct effects to aquatic organisms. The 1-in-10-year 60-day mean is used for 

assessing chronic exposure to fish and aquatic-phase amphibians. The 1-in-10-year 21-day mean 

is used for assessing aquatic invertebrate chronic exposure. 

Because aldicarb is a granule, exposure and risk to terrestrial animals will be assessed using the 

LD50/sq. ft method using the most current version of T-REX at the time of the assessment. In 

addition, given the high toxicity of aldicarb to terrestrial animals, potential for secondary 

exposure (animals that consume contaminated prey) will also be evaluated. 

As stated above, screening level EECs for terrestrial plants inhabiting dry and wetland areas are 

derived using TerrPlant (version 1.2.2, 12/26/2006). This model uses estimates of pesticides in 

runoff to calculate EECs (spray drift will not be evaluated due to the granular formulation). 

EECs are based upon solubility, application rate and minimum incorporation depth. 

Available monitoring data will be used to qualitatively characterize exposure and compare with 

modeling results. The Agency is aware of monitoring conducted by federal and state agencies 

and this information will be considered in the assessment to the extent that data on aldicarb are 

available. 
32 

AgDRIFT is normally used to assess exposures of terrestrial plants by deposited residue in 

terrestrial habitats through spray drift. Since aldicarb applications are all granular in nature, drift 

is not expected to be an issue and will not be assessed. 

The Screening Imbibition Program (SIP v.1.0, Released June 15, 2010) was used to calculate an 

upper bound estimate of wildlife exposure from drinking water using aldicarb’s solubility (5100 

ppm), the most sensitive acute and chronic avian toxicity endpoints (Avian LD50 = 1 mg/kg-bw 

and 1.8 ppm, respectively) and the most sensitive acute and chronic mammalian toxicity 

endpoints (Rat LD50 = 0.9 mg/kg-bw and 0.4 ppm, respectively). Drinking water exposure alone 

was determined to be a potential acute and chronic pathway of concern for avian or mammalian 

species. Therefore, this exposure route will be further evaluated during the conduct of the 

registration review risk assessment. Results for mammalian and avian species are presented in 

the following tables. 

Table 9A . Mammalian SIP Results 

Parameter Acute Chronic 

Upper bound exposure (mg/kg-bw) 1032.00 1032.00 

Adjusted toxicity value (mg/kg-bw) 0.6922 0.0154 

Ratio of exposure to toxicity 1490.8027 67086.12 

Conclusion* 

Drinking water exposure 

alone is a potential acute 

concern for mammals 

Drinking water exposure 

alone is a potential chronic 

concern for mammals 

 

Table 9B. Avian SIP Results 

Parameter Acute Chronic 

Upper bound exposure (mg/kg-bw) 4860.00 4860.00 

Adjusted toxicity value (mg/kg-bw) 0.5192 0.1913 

Ratio of exposure to toxicity 9360.09 25400.2131 

Conclusion* 

Drinking water exposure 

alone is a potential acute 

concern for birds 

Drinking water exposure 

alone is a potential chronic 

concern for birds 

*Conclusion is for drinking water exposure alone. This does not combine all routes of exposure. Therefore, when 

aggregated with other routes (i.e., diet, inhalation, dermal), pesticide exposure through drinking water may 

contribute to a total exposure that has potential for effects to non-target animals. 

9.2. Measures of Effect 

Ecological effects data are used as measures of direct and indirect effects to biological receptors. 

Data were obtained from registrant-submitted studies or from literature studies identified by the 

ECOTOXicology database (ECOTOX). ECOTOX was searched in order to provide more 

ecological effects data to bridge existing data gaps. ECOTOX is a source for locating single 

chemical toxicity data and potential chemical mixture toxicity data for aquatic life, terrestrial 

plants, and wildlife. ECOTOX was created and is maintained by the USEPA, Office of Research 

and Development, and the National Health and Environmental Effects Research Laboratory's 

Mid-Continent Ecology Division (USEPA, 2007a). 
33 

Information on the potential effects of aldicarb on non-target animals is also collected from the 

Ecological Incident Information System (EIIS; USEPA, 2007). The EIIS is a database 

containing adverse effect (typically mortality) reports on non-target organisms where such 

effects have been associated with the use of pesticides. 

Quantitative assessments of risks are limited to those endpoints that can be directly linked to the 

Agency’s assessment endpoints of impaired survival, growth and reproduction. Where available, 

additional sublethal effects observed in both registrant-submitted and open literature studies will 

be evaluated qualitatively. Such effects have included behavioral changes (e.g., lethargy, changes 

in coloration and effects olfaction). 

The screening level assessment of risk for direct effects to non-target organisms makes the 

assumption that toxicity of aldicarb to birds is similar to terrestrial-phase amphibians and 

reptiles. The same assumption is made for fish and aquatic-phase amphibians. 

The acute measures of effects used for animals in this screening-level assessment are the LD50, 

LC50 and EC50. LD stands for "Lethal Dose", and LD50 is the amount of a material, given all at 

once, that is estimated to cause the death of 50% of the test organisms. LC stands for “Lethal 

Concentration” and LC50 is the concentration of a chemical that is estimated to kill 50% of the 

test organisms. EC stands for “Effective Concentration” and the EC50 is the concentration of a 

chemical that is estimated to produce a specific effect in 50% of the test organisms. Endpoints 

for chronic measures of exposure for listed and non-listed animals are the NOAEL/NOAEC. 

NOAEL stands for “No Observed-Adverse-Effect-Level” and refers to the highest tested dose of 

a substance that has been reported to have no harmful (adverse) effects on test organisms. The 

NOAEC (i.e., “No-Observed-Adverse-Effect-Concentration”) is the highest test concentration at 

which none of the observed effects were statistically different from the control. For non-listed 

plants, only acute exposures are assessed (i.e., EC25 for terrestrial plants and EC50 for aquatic 

plants); for listed plants, either the NOAEC or EC05 is used. 

9.3. Integration of Exposure and Effects 

Risk characterization is the integration of exposure and ecological effects characterization to 

determine the potential ecological risk from the use of aldicarb on crops listed and the likelihood 

of direct and indirect effects to non-target organisms in aquatic and terrestrial habitats. The 

exposure and toxicity effects data are integrated in order to evaluate the risks of adverse 

ecological effects on non-target species. For the assessment of aldicarb risks, the risk quotient 

(RQ) method is used to compare exposure and measured toxicity values. EECs are divided by 

acute and chronic toxicity values. The resulting RQs are then compared to the Agency’s LOCs 

(USEPA, 2004). These criteria are used to indicate when aldicarb’s uses, as directed on the 

label, have the potential to cause adverse direct or indirect effects to non-target organisms. As 

noted previously, where data are lacking on the toxicity of aldicarb, risk will be presumed. 

Risk presumptions, along with the corresponding RQs and LOCs are tabulated in Tables 9.3-9.5 

below. 
34 

Table 9.3. Risk Presumptions for Terrestrial Animals 

Risk Presumption RQ LOC 

Birds: 

Acute Risk EEC1/LC50 or LD50/sqft2 or LD50/day3 0.5 

Acute Restricted Use EEC/LC50 or LD50/sqft or LD50/day (or LD50 < 

50 mg/kg) 

0.2 

Acute Endangered Species EEC/LC50 or LD50/sqft or LD50/day 0.1 

Chronic Risk EEC/NOAEC 1 

Wild Mammals: 

Acute Risk EEC/LC50 or LD50/sqft or LD50/day 0.5 

Acute Restricted Use EEC/LC50 or LD50/sqft or LD50/day (or LD50 < 

50 mg/kg) 

0.2 

Acute Endangered Species EEC/LC50 or LD50/sqft or LD50/day 0.1 

Chronic Risk EEC/NOAEC 1 

1

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

2

 mg/ft2 3 mg of toxicant consumed/day

 LD50 * wt. of bird LD50 * wt. of bird 

Table 9.4. Risk Presumptions for Aquatic Animals 

Risk Presumption RQ LOC 

Acute Risk EEC1/LC50 or EC50 0.5 

Acute Restricted Use EEC/LC50 or EC50 0.1 

Acute Endangered Species EEC/LC50 or EC50 0.05 

Chronic Risk EEC/MATC or NOAEC 1 

1

 EEC = (ppm or ppb) in water 

Table 9.5. Risk Presumptions for Plants

Risk Presumption RQ LOC 

Terrestrial and Semi-Aquatic Plants:

Acute Risk EEC1/EC25 1 

Acute Endangered Species EEC/EC05 or NOAEC 1 

Aquatic Plants:

Acute High Risk EEC2

/EC50 1 

Acute Endangered Species EEC/EC05 or NOAEC 1 

1

 EEC = lbs ai/A 

2

 EEC = (ppb/ppm) in water 

 

9.4. Deterministic and Probabilistic Assessment Methods 

The quantitative assessment of risk will primarily depend on the deterministic approach 

described above. An effort will be made to further qualitatively describe risk using probabilistic 

tools that the Agency has developed. These tools have been reviewed by FIFRA Scientific 

Advisory Panels and have been deemed as appropriate means of refining assessments where 

deterministic approaches have identified risks. 

9.5. Endangered Species Assessments 

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the 

Agency will evaluate risks to Federally-listed threatened and/or endangered (listed) species from 

registered uses of aldicarb. This assessment will be conducted in accordance with the Overview 
35 

Document (USEPA, 2004), provisions of the ESA, and the Services’ Endangered Species 

Consultation Handbook (USFWS/NMFS, 1998). 

The assessment of effects associated with the registration of aldicarb is based on an action area. 

The action area is considered to be the area directly or indirectly affected by the federal action, as 

indicated by the exceedance of Agency LOCs used to evaluate direct or indirect effects. The 

Agency’s approach to defining the action area under the provisions of the Overview Document 

(USEPA, 2004) considers the results of the risk assessment process to establish boundaries for 

that action area with the understanding that exposures below the Agency’s defined LOCs 

constitute a no-effect threshold. For the purposes of this assessment, attention will be focused on 

the footprint of the action (i.e., the area where aldicarb application occurs), plus all areas where 

offsite transport may result in potential exposure that exceeds the Agency’s LOCs. Specific 

measures of ecological effect that define the action area for listed species include any direct and 

indirect effects and/or potential modification of its critical habitat, including reduction in 

survival, growth, and reproduction as well as the full suite of sub-lethal effects available in the 

effects literature. Therefore, the action area extends to a point where environmental exposures 

are below any measured lethal or sub-lethal effect threshold for any biological entity at the whole 

organism, organ, tissue, and/or cellular level of organization. In situations where it is not 

possible to determine the threshold for an observed effect, the action area is not spatially limited 

and is assumed to be the entire United States. 

9.6. Drinking Water Assessment 

A drinking water exposure assessment will be conducted to support future human health risk 

assessments of aldicarb. The drinking water assessment will incorporate model estimates of 

aldicarb residues of concern in surface and ground waters. Currently, the residues of concern 

include aldicarb parent, aldicarb sulfoxide, and aldicarb sulfone. Both surface and ground water 

will be modeled at Tier 2 using PRZM for ground water and coupled PRZM and EXAMS with 

the index reservoir watershed for surface water. Scenarios modeled for surface water will be the 

same as those chosen for ecological risk assessment. The drinking water assessment will also 

include a summary of available surface and ground water monitoring data. 

10. Endocrine Disruptor Screening Program 

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potential adverse 

outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and 

chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, 

reproductive, and general or systemic toxicity. These studies include endpoints which may be 

susceptible to endocrine influence, including effects on endocrine target organ histopathology, 

organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, 

and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and 

chronic studies that assess growth, developmental and reproductive effects in different 

taxonomic groups. As part of its reregistration decision, EPA reviewed these data and selected 

the most sensitive endpoints for relevant risk assessment scenarios from the existing hazard 

database. However, as required by FFDCA section 408(p), aldicarb is subject to the endocrine 

screening part of the Endocrine Disruptor Screening Program (EDSP). 
36 

EPA has developed the EDSP to determine whether certain substances (including pesticide 

active and other ingredients) may have an effect in humans or wildlife similar to an effect 

produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator 

may designate.” The EDSP employs a two-tiered approach to making the statutorily required 

determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a 

chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal 

systems. Chemicals that go through Tier 1 screening and are found to have the potential to 

interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA 

will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 

testing is designed to identify any adverse endocrine-related effects caused by the substance, and 

establish a dose-response relationship between the dose and the E, A, or T effect. 

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between 

October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67 

chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. Aldicarb is not 

among the group of 58 pesticide active ingredients on the initial list to be screened under the 

EDSP. Accordingly, as part of registration review, EPA may issue future EDSP orders/data callins, requiring the submission of EDSP screening assays for aldicarb. For further information on 

the status of the EDSP, the policies and procedures, the list of 67 chemicals, future lists, the test 

guidelines and the Tier 1 screening battery, please visit our website: http://www.epa.gov/endo/. 

11. Preliminary Identification of Data Gaps 

The fate and toxicity database for aldicarb is substantially complete. However, the Agency needs 

additional environmental fate and ecological effects studies prior to conducting the planned 

assessments. Data gaps, uncertainties and potential paths forward for the assessment of aldicarb 

are described below. Tables 11.1 and 11.2 identify studies by MRID that offer data for each 

guideline requirement, as well as study classifications and whether or not further data are needed 

in order to support risk assessment. 

835.6100, Footnote 7: the Environmental Chemistry Method for soil is still needed because of 

risks posed by aldicarb and its degradates in soil. The method should be able to measure the 

parent, aldicarb sulfoxide and aldicarb sulfone. This method must be accompanied by an 

independent laboratory validation. 

835.6200, Footnote 7: the Environmental Chemistry Method for water is still needed because of 

risks posed by aldicarb and its degradates in aquatic environments. The method should be able to 

measure the parent, aldicarb sulfoxide and aldicarb sulfone. This method must be accompanied 

by an independent laboratory validation. 
37 

850.2100 An acute passerine study 

Since aldicarb is acutely very highly toxic to other bird species, small passerines may be even 

more susceptible due to their higher metabolic rates. This data will be useful in characterizing 

risks to passerine endangered species. 

850.2300 Avian reproduction study with the mallard duck. 

An avian reproduction study should be repeated since valid endpoints could not be used from the 

previously submitted study. This data will be useful in characterizing risks to passerine 

endangered species and in assessing chronic risks from the exposure from drinking water 

exposure and secondary exposure from consumption of contaminate prey items. 

850.4100 Tier II vegetative vigor and seedling emergence studies

A Tier I seedling emergence study (MRID 47904401) was classified supplemental and cannot be 

used to fulfill the guideline requirement for guideline 850.4100. This study is upgradable if a 

Tier II seedling emergence study is submitted for ryegrass and tomato. Generally a seedling 

emergence study is not required for granular formulations but can be requested on a case-by-case 

basis. A waiver request was granted for the vegetative vigor study in 2009 (DP299878). 

However, aldicarb is a systemic pesticide and plants can uptake the compound. Phytotoxic 

effects (including stunting & necrosis) were observed in ryegrass and tomato in the available 

seedling emergence study. 

 
38 

Table 11-1. Available environmental fate data for aldicarb

158 

Guideline 

(OPPTS) 

Description MRID Classification 

Additional 

Data 

Needed? 

Comments 

835.1230 

(163-1) 

 Leaching 00053380 

00053381 

00053385 

00101915 

00101939 

00102079 

supplemental 

supplemental 

supplemental 

unacceptable 

unacceptable 

supplemental 

no 

mobility 

requirement 

fulfilled by 

835.1240 

835.1240 

(163-1) Adsorption/Desorption 42498202 acceptable no 

 835.1410 

(163-2) Laboratory Volatility not required no 

 835.2120 

(161-1) 

Hydrolysis 00053377 

00096547 

00102011 

00102048 

00102057 

00102072 

00102065 

unacceptable 

unacceptable 

unacceptable 

unacceptable 

unacceptable 

unacceptable 

acceptable 

no 

 835.2240 

(161-2) 

Photodegradation in water 00102067 

00102068 

42498201 

unacceptable 

supplemental 

acceptable 

no 

835.2370 

(161-4) 

Photodegradation in air waived no 

835.2410 

(161-3) 

Photodegradation on soil waived no 

 835.4100 

(162-1) 

Aerobic soil metabolism 00029989 

00035365 

00053366 

00080820 

00093640 

00093641 

00093642 

00096968 

00101934 

00102050 

00102051 

00102054 

00102071 

00101915 

43805702 

44005001 

unacceptable 

acceptable 

acceptable 

acceptable 

acceptable 

supplemental 

acceptable 

unacceptable 

acceptable 

unacceptable 

supplemental 

supplemental 

acceptable 

supplemental 

unacceptable 

acceptable 

no 

835.4200 

(162-2) 

Anaerobic soil metabolism no open literature 

data is 

sufficient for 

data needs 

 835.4300 

(162-4) 

Aerobic aquatic 

metabolism 

 no open literature 

data is 

sufficient for 
39 

Table 11-1. Available environmental fate data for aldicarb

data needs 

 835.4400 

(162-3) 

Anaerobic Aquatic 

Metabolism 43805701 

unacceptable no open literature 

data is 

sufficient for 

data needs 

 835.6100 

(164-1) 

Terrestrial Field 

Dissipation 

00036313 

00053364 

00068252 

00080815 

00101910 

00101923 

00101935 

00101936 

00101937 

00101968 

00102061 

00102064 

00102078 

unacceptable 

unacceptable 

unacceptable 

unacceptable 

unacceptable 

unacceptable 

supplemental 

supplemental 

supplemental 

unacceptable 

unacceptable 

supplemental 

supplemental 

no 

results of all 

studies taken 

together 

satisfies data 

needs 

835.6200 

(164-2) 

Aquatic Field Dissipation 00094799 

00101940 

unacceptable 

unacceptable not required no aquatic 

uses 

835-6300 

(164-3) 

Forestry Field Dissipation not required no forestry 

uses 

850.1730 

(165-4) 

Fish Bioconcentration 

Factor not required Kow < 1000 

835.6100 

Footnote 7 

Environmental Chemistry 

Method in soil 

 yes 

835.6200 

Footnote 7 

Environmental Chemistry 

Method in Water 

 yes 

Non-Guideline Retrospective Monitoring 

Studies 

46793701 

46793702 

46793703 

46793704 

46793705 

46793706 

supplemental 

supplemental 

supplemental 

supplemental 

supplemental 

supplemental 

no 

 
40 

11.1. Ecological Effects 

Table 11.2 identifies studies by MRIDs that offer data for each guideline requirement, as well as 

study classifications and whether or not further data are needed in order to support risk 

assessment.

Table 11.2 Submitted Ecological Toxicity Data for Aldicarb. 

Guideline Data 

Requirement 

Submitted 

Studies (MRID)

Study 

Classification

Additional 

Data 

Needed? 

Current Additional Data Need 

850.2100 Avian Acute Oral MRID 00107398 Acceptable Yes A passerine study is needed (see 

explanation above) 

850.2200 Avian Subacute 

Dietary 

MRID 1096727 

MRID 00102132

Acceptable 

Acceptable 

No 

850.2300 Avian 

Reproduction 

MRID 48156905

MRID 48198801

Supplemental 

Supplemental 

Yes A new reproduction study is needed with 

the mallard duck (see explanation above)

870.3100 Mammal Acute MRID 00057333 Acceptable No 

870.3800 Mammal 

Reproduction 

MRID 42148401 Acceptable No 

850.3020 Honey Bee Acute 

Contact 

MRID 00036935 Acceptable No 

850.1075 Freshwater Fish 

Acute 

MRID 40098001

MRID 40098001

Acceptable 

Acceptable 

No 

No 

850.1400 Freshwater Fish 

Chronic 

MRID 44598601 Acceptable No 

850.1010 Freshwater 

Invertebrate 

Acute 

Moore et al 1998 Acceptable No 

850.1300 Freshwater 

Invertebrate 

Chronic 

MRID 45592112 Acceptable No 

850.1025 Estuarine/Marine 

Fish Acute 

MRID40228401 Acceptable No 

850.1400 Estuarine/Marine 

Fish Chronic 

MRID 00066341 Acceptable No 

850.1035 Estuarine/Marine 

Invertebrate 

Acute 

MRID 40228401

MRID 00066341

Acceptable 

Acceptable 

No 

No 

850.1350 Estuarine/Marine 

Invertebrate 

Chronic 

MRID 00066341 Acceptable No 

850.4100 

850.4150 

Terrestrial plants MRID 47904401 Supplemental Yes Tier II Vegetative Vigor and Seedling 

Emergence studies are needed (see 

explanation above) 
41 

Guideline Data 

Requirement 

Submitted 

Studies (MRID)

Study 

Classification

Additional 

Data 

Needed? 

Current Additional Data Need 

850.4400 

850.5400 

Aquatic plants MRID 47904402

MRID 40228401

Acceptable 

Acceptable 

No 

No 

12. References 

Brassard, David, Katherine Stebbins, and Derek Berwald. 2011. BEAD Chemical Profile for 

Registration Review: Aldicarb. Internal EPA Memorandum to Susan Bartow, Ann 

Overstreet, and Eric Olsen dated December 8, 2011. 

 Bromilow, R.H., Briggs, G.G., Williams, M.R., Smelt, J.H., Tuinistra, Th.L.G.M., and W.A. 

Traag. 1986. The role of ferrous ions in the rapid degradation of oxamyl, methomyl, and 

aldicarb in anaerobic soils. Pesticide Science 17:535-547. 

Fellers, G.M, L.L. McConnell, D. Pratt, S. Datta. 2004. Pesticides in Mountain Yellow-Legged 

Frogs (Rana Mucosa) from the Sierra Nevada Mountains of California, USA. 

Environmental Toxicology & Chemistry 23 (9):2170-2177. 

Fletcher, J.S., J.E. Nellessen, and T.G. Pfleeger. 1994. Literature review and evaluation of the 

EPA food-chain (Kenaga) nomogram, and instrument for estimating pesticide residues on 

plants. Environmental Toxicology and Chemistry 13 (9), 1383-1391. 

Health Effects Division. 2005. Estimation Of Cumulative Risk From N-Methyl Carbamate 

Pesticides: Preliminary Assessment. United States Environmental Protection Agency 

EPA-HQ-OPP-2003-0360-0013.

Hoerger, F., and E.E. Kenaga. 1972. Pesticide residues on plants: Correlation of representative 

data as a basis for estimation of their magnitude in the environment. In F. Coulston and F. 

Korte, eds., Environmental Quality and Safety: Chemistry, Toxicology, and Technology, 

Georg Thieme Publ, Stuttgart, West Germany, pp. 9-28. 

LeNoir, J.S., L.L. McConnell, G.M. Fellers, T.M. Cahill, J.N. Seiber. 1999. Summertime 

Transport of Current-use pesticides from California’s Central Valley to the Sierra Nevada 

Mountain Range,USA. Environmental Toxicology & Chemistry 18(12): 2715-2722. 

Lightfoot, E.N., Thorne, P.S., Jones, R.L., Hansen, J.L., and R.R. Romine. 1987. 

Laboratory studies on mechanisms for the degradation of aldicarb, aldicarb sulfoxide, and 

aldicarb sulfone. Environmental Toxicology and Chemistry. 6:377-394. 

Mayer, F.L. and M.R. Ellersieck. 1986. Manual of acute toxicity: Interpretation and data base 

for 410 chemicals and 66 species of freshwater animals. USDI, FWS Publication 160, 

Washington, DC. 506 pp. MRID 40098001. 
42 

McConnell, L.L., J.S. LeNoir, S. Datta, J.N. Seiber. 1998. Wet deposition of current-use 

pesticides in the Sierra Nevada mountain range, California, USA. Environmental 

Toxicology & Chemistry 17(10):1908-1916. 

Office of Pesticide Programs. 2007. Revised N-Methyl Carbamate Cumulative Assessment.

United States Environmental Protection Agency. 

http://www.epa.gov/oppsrrd1/REDs/nmc_revised_cra.pdf

Sparling, D.W., G.M. Fellers, L.L. McConnell. 2001. Pesticides and amphibian 

population declines in California, USA. Environmental Toxicology & Chemistry 20(7): 

1591-1595. 

Suffolk County Dept. of Health Services. 1999. Water Quality Monitoring Program to 

Detect Pesticide Contamination in Groundwaters of Nassau and Suffolk Counties, NY, 

June, 1999. 

Suffolk County Dept. of Health Services. 2000. Water Quality Monitoring Program to 

Detect Pesticide Contamination in Groundwaters of Nassau and Suffolk Counties, NY, 

December, 2000. 

U.S. Environmental Protection Agency (U.S. EPA). 1998. Guidance for Ecological Risk 

Assessment. Risk Assessment Forum. EPA/630/R-95/002F, April 1998. 

USEPA. 2004. Overview of the Ecological Risk Assessment Process in the Office of Pesticide 

Programs, United States Environmental Protection Agency (USEPA). Washington, D.C.: 

Government Printing Office. Available at http://www.epa.gov/espp/consultation/ecoriskoverview.pdf . 

USEPA. 2007. Ecological Incident Information System. 

http://www.epa.gov/pesticides/science/efed/policy_guidance/team_authors/endangered_s

pecies_reregistration_workgroup/esa_incident_guidance.htm#eiis

USEPA. 2007a. ECOTOXicology Database. Office of Research and Development National 

Health and Environmental Effects Research Laboratory’s (NHEERL’s) Mid-Continent 

Ecology Division (MED). http://cfpub.epa.gov/ecotox/. 

U.S. EPA. 2006. Aldicarb Ecological Risk Assessment (RED). Office of Prevention, 

Pesticides, and Toxic Substances. Office of Pesticide Programs, EFED. Washington, 

D.C. September 2006. 

USFWS/NMFS 2004. Memorandum to Office of Prevention, Pesticides, and Toxic Substances, 

U.S. EPA conveying an evaluation by the U.S. Fish and Wildlife Service and National 

Marine Fisheries Service of an approach to assessing the ecological risks of pesticide 

products. 
43 

USEPA. 2009. Guidance for Selecting Input Parameters in Modeling the Environmental Fate 

and Transport of Pesticides. Version 2.1. U.S. Environmental Protection Agency, Office 

of Pesticide Programs, Environmental Fate and Effects Division, Oct. 22, 2009. Online 

at: http://www.epa.gov/oppefed1/models/water/input_parameter_guidance.htm

U.S. Fisheries and Wildlife Service and National Marine Fisheries Service (USFWS/NMFS). 

1998. Endangered Species Consultation Handbook: Procedures for Conducting 

Consultation and Conference Activities Under Section 7 of the Endangered Species Act. 

Final Draft, United States Fish and Wildlife Service (USFWS) and National Marine 

Fisheries Service (NMFS), Washington, D.C.: Government Printing Office. 

U.S. Geological Survey (USGS). 2011. 2002 Pesticide Use Maps. U.S. Geological Survey, 

National Water-Quality Assessment (NAWQA) Program, Pesticide National Synthesis 

Program. Accessed on July 14, 2011. Online at: 

http://water.usgs.gov/nawqa/pnsp/usage/maps/compound_listing.php?year=02

Vink, J.P.M. and S.E.A.T.M. Van der Zee. 1997. Pesticide biotransformation in surface waters: 

multivariate analyses of environmental factors at field sites. Water Research 

31(11):2858-2868. 

Internal EPA Documents

Dutta, Subijoy. 1999. Drinking Water Memorandum for Aldicarb for the Reregistration 

Eligibility Decision Document (RED). Internal EPA Memorandum to Robert McNally 

dated April 4, 1999. 

D247759. Dutta, Subijoy. 1999. Updated Drinking Water Assessment for Aldicarb (Temik®

15G). Internal EPA Memorandum dated September 21, 1999. Same as D254590. 

D246940. 2001. Carlton, James and Richard Feldhausen. 2003 RED.

D246901. Environmental Fate and Effects Division. EFED Chapter for the Reregistration 

Eligibility Document for Aldicarb. Dated May 15, 2001.

D299881. Shanaman, Lucy. Refinement to Tier 2 Drinking Water Assessment Tobacco Uses of 

Aldicarb and its Major Degradates Aldicarb Sulfoxide and Aldicarb Sulfone. Internal 

EPA Memorandum to Christine Olinger dated April 10, 2009. 

D316754. Angier, Jonathan. 2005. Tier 2 Drinking Water Assessment for Aldicarb and its Major 

Degradates Aldicarb Sulfoxide and Aldicarb Sulfone. Internal EPA Memorandum to 

Robert McNally dated April 4, 2005. 

D332265. Angier, Jonathan, Diana Eignor, Michelle Embry, Jeannette Martinez, Donna Randall, 

Dana Spatz, and Nelson Thurman. 2006. Environmental Fate and Effects Division 

Aldicarb Revised RED. Internal EPA Memorandum to Bob McNally, Ann Overstreet, 

and Sherri Kinard dated September 27, 2006. 
44 

D333309. Thurman, Nelson and Jonathan Angier. 2006. Drinking Water Exposure Assessment 

for Total Aldicarb Residues (Parent, Aldicarb Sulfoxide, and Aldicarb Sulfone) Based on 

the N-Methyl Carbamate Cumulative Risk Assessment. Internal EPA Memorandum to 

Sherri Kinard and Felicia Fort dated October 23, 2006. 

D348436. Thurman, Nelson and Jonathan Angier. 2008. Drinking Water Exposure Assessment 

for Proposed Expansion of Aldicarb Use on Potatoes Into 6 Additional States (CO, MI, 

MN, ND, SD, WY). Internal EPA Memorandum to John Hebert and Christine Olinger 

dated August 26, 2008. 
45 

Appendix A. Submitted Environmental Fate & Ecological Effects Studies 

Environmental Fate Studies 

00035365. Bull, D.L., R. A. Stokes, J. R. Coppedge, .1970. Further studies of the fate of 

Aldicarb in soil. Journal of Economic Entomology 63(4):1283-1289. Also in unpublished 

submission received Jul 26, 1971. Submitted by Union Carbide Corp., Washington, D.C. 

00036313. Gunther, F.A., G. E. Carman, and R. C. Baines, 1975. Aldicarb (Temik®) Residues in 

Oranges, Orange Leaves, and Soil after Soil Application in an Orange Grove. 

Unpublished study received Oct 10, 1975 under 6G1689. Prepared in cooperation with 

Univ. of California - Riverside, Citrus Research Center and Agricultural Experiment 

Station, Dept. of Entomology and others. Submitted by Union Carbide Corp., 

Washington, D.C. 

00053364. Bull, D. L. 1968. Metabolism of UC-21149 (2-Methyl-2-(methythio)- 

propionaldehyde-O-(methylcarbamoyl)oxime) in cotton plants and soil in the field. 

Journal of Economic Entomology 61(6):1598- 1602. Also in unpublished submission 

received Jan 18, 1977 under 1016-Ex-37; Submitted by Union Carbide Corp., Arlington, 

Va. 

00053377. Andrawes, N.R., and G. C. Holsing. 1976. Hydrolysis of UC-21865 Sulfo-carb 

Pesticide in Aqueous Buffer Solutions. Project No. 111A14. (Unpublished study received 

Jan 18, 1977. Submitted by Union Carbide Corp., Arlington, Va. 

00053380. Richey, F.A., Jr., and W. J. Bartley, W.J. 1972. Temik Aldicarb Pesticide: Water 

Leaching of Aldicarb, Aldicarb Sulfoxide, Aldicarb Sulfone and Internal Standard 

Chloride Ion in Columns of Four Soil Types. Project No. 111A12. Unpublished study 

received Jan 18, 1977 under 1016-EX-37; submitted by Union Carbide Corp., Arlington, 

Va. 

00053381. Richey, jr., F.A., H. H. Moorefield. 1972. Temik--Aldicarb Pesticide: Upward 

Movement of Aldicarb through Soil during Water Evaporation: Project No. 111A12. 

(Unpublished study received Jan 18, 1977. Submitted by Union Carbide Corp., Arlington, 

Va. 

00053385. Romine, R.R., C. B. Halstead., and C. E. Gibson. 1968. Temik Insecticide: Leaching 

Characteristics of Temik 10G in Soils. Project No. 111A13. Unpublished study received 

Jan 18, 1977 under 1016-EX-37; submitted by Union Carbide Corp., Arlington, Va. 

00068252. Romine, R. R. and R. L. Meeker. 1972. Temik Aldicarb Pesticide: Leaching of 

Aldicarb into Sandy Soil with Irrigation of a Temik Treated Sugar Beet Field. UCC 

Project Report No. 17079. Unpublished study received Aug 4, 1977 under 1016-79; 

submitted by Union Carbide Corp., Arlington, Va. 

00096547. Spiegel, M.H. and R. A. Conway. 1982. Hydrolysis Studies of Aldicarb, Aldicarb 
46 

Sulfoxide, and Aldicarb Sulfon. Project III. (Unpublished study received Mar 9, 1982. 

Submitted by Union Carbide Agricultural Products Co., Inc., Ambler, Pa. 

00102011. Lykins, H. 1969. Temik Insecticide: The Effect of Temperature and pH on the 

Stability of Temik, Temik Sulfoxide and Temik Sulfone in Water. Project No. 111A13. 

(Unpublished study received Jun 25, 1973. Submitted by Union Carbide Corp., 

Washington, DC. 

00101935. Andrawes, N., W. Bagley., and R. Herrett. 1968. Temik Metabolism: Fate of 14CTemik in Cultivated Soil. File No. 9218. Unpublished study received Apr 18, 1969 under 

9F0798. Submitted by Union Carbide Corp. 

00101939. Clarkson, V., B. Rowe, and R. Romine. 1968. Temik Insecticide: Field Evaluation of 

the Persistence and Movement of Temik and Its Carbamate Metabolites in Soil. File No. 

10485. (Unpublished study received Apr 18, 1969. Submitted by Union Carbide Corp., 

New York, NY. 

00101940. Clarkson, V., B. Rowe, an R. Romine. 1968. Temik Insecticide: Field Evaluation of 

the Persistence of Temik and Its Carbamate Metaolites in Pond Water and Their Effect 

on Pond Fauna. File No. 10491. Unpublished study received Apr 18, 1969. Submitted 

by Union Carbide Corp., New York, NY. 

00101968. Union Carbide Corp. 1969. Soil Decline of Aldicarb. Unpublished study received Aug 

20, 1970. 

00102048. Lykins, H. and R. Meeker. 1971. Aldicarb Pesticide: Stability of Aldicarb in Water. 

Project No. 111A13, File No. 16060. Unpublished study received Dec 6, 1977. Submitted 

by Union Carbide Corp., Arlington, VA. 

00102057. Stephen, J. and J. Durden. 1969. A Study of the Decomposition of Temik, Temik 

Sulfoxide and Temik Sulfone in Water at 100 (degrees). Project No. 111A28, File No. 

11815. Unpublished study received Dec 6, 1977 under 1016-69; submitted by Union 

Carbide Corp., Arlington, VA. 

00102065. Andrawes, N. and R. Meeker. 1976. Hydrolysis of Temik Aldicarb Pesticide in 

Aqueous Buffer Solutions. Project No. 111A13, File No. 22263. Unpublished study 

received Dec 6, 1977 under 1016- 69; submitted by Union Carbide Corp., Arlington, VA. 

00102067. Andrawes, N. and R. Meeker. 1976. Photochemical Transformation of Aldicarb.

Project No. 111A13, File No. 22335. (Unpublished study received Dec 6, 1977 under 

1016-69; submitted by Union Carbide Corp., Arlington, VA. 

00102061. Woodham, D., R. Edwards, and R. Reeves. 1973. Total toxic aldicarb residues in soil, 

cottonseed, and cotton lint following a soil treatment with the insecticide on the Texas 

high plains. J. Agr. Food Chem. 21(2):303-307. Also in unpublished submission received 

Dec 9, 1977. Submitted by Union Carbide Corp., Arlington, VA. 
47 

00102064. Andrawes, N., W. Bagley, and R. Herrett. 1971. Fate and carryover properties of 

Temik aldicarb pesticide (2-methyl-2-(methylthio)- propionaldehyde -O-

(methylcarbamoyl)oxime| in soil. Agricultural and Food Chemistry 19(4):727-730. Also 

in unpublished submission received Dec 6, 1977. Submitted by Union Carbide Corp., 

Arlington, VA. 

00102068. Andrawes, N. and R. Meeker, R. 1976. Photostability of Aldicarb Sulfoxide. Project 

No. 111A13, File No. 22325. Unpublished study received Dec 6, 1977 under 1016-69; 

submitted by Union Carbide Corp., Arlington, VA. 

00102072. Bartley, W., and D. Heywood. 1965. Metabolism Studies: Hydrolytic Stability of UC 

21149. Project No. 855-31101-7073. Unpublished study received Dec 6, 1977 under 

1016-69; submitted by Union Carbide Corp., Arlington, VA. 

00102079. Leistra, M. and J. Smelt, and T. Lexmond. 1976. Conversion and leaching of aldicarb 

in soil columns. Pestic. Sci. 7:471-482. Also in unpublished submission received Dec 6, 

1977 under 1016-69; submitted by Union Carbide Corp., Arlington, VA. 

42498201. Das, Y. 1990. Photodegradation of (S-Methyl-14C)-Aldicarb in Aqueous Solution 

Buffered at pH 5 under Artificial Sunlight. Lab Project Number: 90021. Unpublished 

study prepared by Innovative Scientific Services, Inc. 91 p. 

42498202. Dykes, J. 1990. Soil Adsorption/Desorption with 14C-Aldicarb. Lab Project Number: 

37352. Unpublished study prepared by Analytical Bio-Chemistry Laboratories, Inc. 326 

p. 

46793701. Jones, R.L., and T.S. Ramanarayanan. 2006. TEMIK® brand 15G Aldicarb Pesticida: 

Summary of Five Retrospective Ground Water Monitoring Studies conducted for 

Aldicarb and Its Metabolites in the Pacific Northwest, California, Texas, Mississippi 

Delta and the Southeast Regions of the United States in 2005. Bayer CropScience Study 

No. RAAVY010. 

46793702. Freeseman, P.I., R.L. Jones, R.E. Lee, U.B. Handihalli, and D.R. Wyatt. 2006. A 

Retrospective Groundwater Monitoring Study for Aldicarb and Its Metabolites in the 

Pacific Northwest. Bayer CropScience Study No. RAAVY005. 

46793703. Lenz, M, R.L. Jones, D.R. Wyatt, U.B. Handihalli, and R.E. Lee. 2006. A 

Retrospective Groundwater Monitoring Study for Aldicarb and Its Metabolites in 

California. Bayer CropScience Study No. RAAVY006. 

46793704. Mosier, D.G., R.L. Jones, U.B. Handihalli, and R.E. Lee. 2006. A Retrospective 

Groundwater Monitoring Study for Aldicarb and Its Metabolites in Texas. Bayer 

CropScience Study No. RAAVY007. 
48 

46793705.Wyatt, D.R., R.L. Jones, U.B. Handihalli, and R.E. Lee. 2006. A Retrospective 

Groundwater Monitoring Study for Aldicarb and Its Metabolites in Mississippi Delta 

Region. Bayer CropScience Study No. RAAVY008. 

46793706. Lee, R.E., R.L. Jones, D.R. Wyatt, and U.B. Handihalli. 2006. A Retrospective 

Groundwater Monitoring Study for Aldicarb and Its Metabolites in the Southeastern 

United States. Bayer CropScience Study No. RAAVY009. 
49 

Ecological Effects Studies 

098301 Aldicarb Eco Effects Bibliography 

71-1 Avian Single Dose Oral Toxicity

MRID Citation Reference 

102038 Hudson, R.; Tucker, R.; Haegele, M. (1972) Effect of age on sensitivity: Acute oral toxicity of 14 pesticides to mallard ducks of several 

ages. Toxicology and Applied Pharmacology (22):556- 561. (Also In 

unpublished submission received Oct 26, 1977 under 1016-69; 

submitted by Union Carbide Corp., Arlington, VA; CDL:096397-E) 

107398 Fink, R.; Beavers, J.; Brown, R. (1979) Final Report: Acute Oral LD50--

Mallard Duck: Technical Grade Aldicarb: Project No. 142- 119. 

(Unpublished study received Dec 12, 1979 under 1016-78; prepared by 

Wildlife International, Ltd., submitted by Union Carbide Corp., Arlington, 

VA; CDL:099120-A) 

148695 Balcomb, R.; Stevens, R.; Bowen, C. (1984) Toxicity of 16 granular 

insecticides to wild-caught songbirds. Bulletin of Environmental 

Contamination and Toxicology 33:302-307. 

148698 Benjamini, L. (1981) Testing aldicarb as a bird repellent in a sprouting 

sugar beet field. Phytoparasitica 9(2):89-94. 

148703 Hill, E.; Camardese, M. (1984) Toxicity of anticholinesterase insecticides to birds: Technical grade versus granular formula- tions. 

Ecotoxicology and Environmental Safety 8:551-563. 

148704 Hilbig, V.; Westphal, D.; Lucas, K.; et al. (1979) Vergleichende 

Untersuchungen zur Vogeltoxizitaet mit Zwei Granulatformulier- ungen 

des Nematizides Temik [Comparative Studies of the Toxicity to Birds of 

Two Granulated Formulations of Temik Nematocides]: Vetmed-Berichte 

2/1979. Unpublished study prepared by Institute of Veterinary Medicine. 

24 p. 

148707 Medd, R.; Burrows, I.; Roberts, N.; et al. (1972) The Determination of 

the Single Dose Oral LD50 (24 Hour Value) and Residual Levels of 

Temik (Coal) in the Pheasant: Amended: 5355/72/751. Unpub- lished 

study prepared by Huntingdon Research Centre. 28 p. 

148709 Ross, D.; Roberts, N.; Cameron, D. (1977) A Comparison of the Acute 

Oral Toxicity (LD50) of Three Formulations of Temik to the Japanese 

Quail: UNC 68 W/771042. Unpublished study prepared by Hun- tingdon 

Research Centre. 12 p. 

5008363 Hudson, R.H.; Haegele, M.A.; Tucker, R.K. (1979) Acute oral and 

percutaneous toxicity of pesticides to mallards: correlations with 

mammalian toxicity data. Toxicology and Applied Pharmacology 

47(3):451-460. 

42446501 Kendall, R. (1992) Behavior, Survivability and Biochemical Response of 

Wild Northern Bobwhites (Colinus virginianus) Dosed with Temik: Lab 

Project Number: 08034. Unpublished study prepared by Clemson Univ., 

Inst. of Wildlife and Environ. Tox. 34 p. 

00160000 Hudson, R.; Tucker, R.; Haegele, M. (1984) Handbook of toxicity of 
50 

pesticides to wildlife: Second edition. US Fish and Wildlife Service: 

Resource Publication 153. 91 p. 

71-2 Avian Dietary Toxicity 

MRID Citation Reference 

76066 Woodard Research Corporation (1965) UC-21149: Safety Evaluation on 

Fish and Wildlife: (Bobwhite Quail and Rainbow Trout). (Unpublished 

study received Jul 26, 1966 under 1016-69; submitted by Union Carbide 

Corp., Arlington, Va.; CDL:231174-B) 

76067 Beliles, R.P.; Knott, W.; Wright, L. (1966) UC-21149 10%: Summary of 

Safety Evaluation on Fish and Wildlife. Summary of studies 231174-A 

and 231174-B. (Unpublished study received Jul 26, 1966 under 1016-

69; prepared by Woodard Research Corp., submitted by Union Carbide 

Corp., Arlington, Va.; CDL:231174-D) 

80706 Beliles, R.P.; Knott, W.; Wright, L. (1966) UC-21149: Safety Evaluation 

on Fish and Wildlife: (Bobwhite Quail and Rainbow Trout). (Unpublished 

study received Mar 2, 1967 under 7F0573; prepared by Woodard 

Research Corp., submitted by Union Carbide Corp., Charleston, W.Va.; 

CDL:090072-O) 

102132 Fink, R.; Beavers, J.; Brown, R. (1979) Final Report: Eight-day Dietary 

LC50--Bobwhite Quail: Technical Grade Aldicarb: Project No. 142-118. 

(Unpublished study received Dec 12, 1979 under 1016-78; prepared by 

Wildlife International Ltd., submitted by Union Carbide Corp., Arlington, 

VA; CDL:099120-B) 

115301 Hill, E.; Camardese, M. (1981) Subacute toxicity testing with young 

birds: Response in relation to age and interest variabil- ity of LC50 

estimates. Avian and Mammalian Wildlife Toxicology 2:41-65. (Also In 

unpublished submission received Oct 7, 1982 under 201-142; submitted 

by Shell Chemical Co., Washington, DC; CDL:248514-U) 

148706 Medd, R.; Roberts, N. (1972) Palatability and Acceptability of Te- mik 

(Corn Cob and Coal Formulations) to the Pheasant and the Pi- geon: 

5419/72/815. Unpublished study prepared by Huntingdon Re- search 

Centre. 31 p. 

22923 Hill, E.F.; Heath, R.G.; Spann, J.W.; et al. (1975) Lethal Dietary 

Toxicities of Environmental Pollutants to Birds: Special Scientific Report-

-Wildlife No. 191. (U.S. Dept. of the Interior, Fish and Wildlife Service, 

Patuxent Wildlife Research Center; unpublished report) 

45592114 Handley, J.; Grant-Salmon, D.; Bartlett, A. (1995) The Acute Toxicity of 

Aldicarb Sulfoxide to Daphnia Magna: Lab Project Number: 282/442. 

Unpublished study prepared by Safepharm Laboratories Limited. 26 p. 

Aldicarb sulfone = PC Code 110802 

71-3 Mammal Acute 

101957 Lavoie, K. (1963) Bioassay Record: UC-21149: Peromyscus: Test No. 

R-14. (U.S. Fish and Wildlife Service, Denver Wildlife Research Center; 

unpublished study, CDL:091373-AC) 

43961101 McCann, J.; Teeters, W.; Urban, D. et al. (1981) A short-term dietary 
51 

toxicity test on small mammals. p. 132-142 of the Second Conference of 

Avian and Mammalian Wildlife Toxicology, Lamb, D.; Kenaga, E. Eds.; 

Published in American Society for Testing and Materials, ASTM STP 

757; 1981. 

71-5 Simulated or Actual Field Testing 

MRID Citation Reference 

100231 or 

101959 

 Lund, R.C.; Haines, R.G. (1969) Field Evaluation of Temik 10G Aldicarb 

Pesticide Potential Hazard to Whitetail Deer and Cottontail Rabbits from 

Simulated Spills. (Unpublished study re- ceived Oct 27, 1969 under 

1016-EX-30; prepared in cooperation with New Jersey, Fish and Game 

Commission, Black River State Game Field Station, submitted by Union 

Carbide Corp., Arlington, Va.; CDL:126506-C) 

101956 Back, R. (1968) Temik 10G Granular Pesticide: Field Evaluation of 

Potential Hazard to Bobwhite Quail. (Unpublished study received Apr 

18, 1969 under 9F0798; submitted by Union Carbide Corp., New York, 

NY; CDL:091373-AB) 

101960 Clarkson, V.; Haines, R.; Hennsley, W.; et al. (1969) Report on 

Additional Field Tests with Temik 10G Aldicarb Pesticide on the 

Potential Hazard to Bobwhite Quail. (Unpublished study received Aug 

20, 1970 under 0F1008; submitted by Union Carbide Corp., 

Washington, DC; CDL:091748-C) 

101961 Haines, R. (1970) Field Evaluation of Potential Hazard of Temik 10G 

Aldicarb Pesticide to Valley Quail and Ring-necked Pheasants: Trial I.

(Unpublished study received Aug 20, 1970 under 0F1008; submitted by 

Union Carbide Corp., Washington, DC; CDL:091748-D) 

101962 Haines, R. (1970) Field Evaluations of Potential Hazard of Temik 10G 

Aldicarb Pesticide to Valley Quail and Ring-necked Pheas- ants: Trial II.

(Unpublished study received Aug 20, 1970 under 0F1008; submitted by 

Union Carbide Corp., Washington, DC; CDL:091748-E) 

102167 Union Carbide Corp. (1968) Temik 10G Insecticide: Field Evaluation of 

Potential Hazard to Bobwhite Quail. (Unpublished study re- ceived Dec 

5, 1968 under 1016-EX-30; CDL:131937-A) 

132989 Ashton, A.; Jackson, W. (1983) Letter sent to Union Carbide dated Nov 

18, 1983: Temik field trial (Michigan): Effects on wild- life|. (Unpublished 

study received Dec 13, 1983 under 264-330; prepared by Bowling 

Green State Univ., submitted by Union Carbide Agricultural Products 

Co., Inc., Research Triangle Park, NC; CDL:251947-A) 

144970 Jackson, W. (1984) Letter sent to T. DeWitt dated June 21, 1984: [A 

Field study to evaluate the hazard to birds in Corn Fields treated with 

Temik. 6 p. 

148685 Ross, D.; Roberts, N.; Eichler, A. (1977) Temik 10G--Gypsum Formulation (Blue): Wildlife Surveys following Application to Four Sugar Beet 

and Four Potato Fields: UNC 57/774581. Unpublished study prepared 

by Huntingdon Research Centre. 255 p. 

148691 Tait, F. (1972) Aldicarb: Wild Life Survey 1972. Unpublished study 

prepared by Duphar-Midox Ltd. 28 p. 
52 

148692 United Kingdom, Ministry of Agriculture, Fisheries & Food, Pest 

Infestation Control Laboratory (1974) A Study of the Effects of Aldicarb 

or Wildlife. Unpublished study. 65 p. 

148693 Brown, P.; Bunyan, P.; Stanley, P.; et al. (1975) Field Surveil- lance of 

the Possible Wildlife Hazards Associated with the Use of the 

Nematicide, Aldicarb: Chemistry Department Report No. 17. 

Unpublished study prepared by U.K. Ministry of Agriculture, Fisheries 

and Food, Pest Infestation Control Laboratory. 57 p. 

148696 Back, R. (1968) Temik 10G Granular Pesticide: Field Evaluation of 

Potential Hazard to Bobwhite Quail. Unpublished study prepared by 

Union Carbide Corp. 15 p. 

148697 Benjamini, L. (1981) The efficacy of seed treatment with aldicarb to 

establish conditioned aversion in birds to sprouting sugar beets. 

Phytoparasitica 9(1):3-9. 

148698 Benjamini, L. (1981) Testing aldicarb as a bird repellent in a sprouting 

sugar beet field. Phytoparasitica 9(2):89-94. 

148699 Clarkson, V.; Rowe, B. (1970) Temik Insecticide: Field Evaluations of 

the Toxic Hazard of Temik Formulations 10G, 10GV, 10GC and 

10GVB4 to Bobwhite Quail: Project No. 111B32: File No. 12676. 

Unpublished study prepared by Union Carbide Corp. 15 p. 

148700 or 

101962 or 

101961 

 Haines, R. (1970) Temik 10G Granular Pesticide: Field Evaluations of 

Potential Hazard of Temik 10G Aldicarb Pesticide to Valley Quail and 

Ring-necked Pheasants in Sugar Beet Plantings: Trial III. Unpublished 

study prepared by Union Carbide Corp. 8 p. 

148701 Haines, R. (1971) Continued Field Evaluations on the Potential Haz- ard 

of Temik 10G Aldicarb Pesticide to Valley Quail and Ring- necked 

Pheasants in a Cotton Planting. Unpublished study pre- pared by Union 

Carbide Corp. 7 p. 

148702 Haines, R. (1971) Continued Field Evaluations on the Potential Hazards of Temik 10G Aldicarb Pesticide to Bob White Quail in Cot- ton 

Plantings. Unpublished study prepared by Union Carbide Corp. 7 p. 

148705 Lund, R. (1970) Summary of Field Observations: Potential Hazard of 

Temik 10G Aldicarb Pesticide to Ring-necked Pheasant ... from 

Simulated Spills. Unpublished study prepared by State of New Jersey, 

Dept. of Conservation and Economic Development, Black River Wildlife 

Management Area. 2 p. 

148706 Medd, R.; Roberts, N. (1972) Palatability and Acceptability of Te- mik 

(Corn Cob and Coal Formulations) to the Pheasant and the Pi- geon: 

5419/72/815. Unpublished study prepared by Huntingdon Re- search 

Centre. 31 p. 

40607502 Fletcher, D. (1988) Application of Temik Brand 15G Aldicarb to Three 

Major Crops: A Terrestrial Verbebrate Field Study: BLAL Study No. 87 

FV 3. Unpublished study prepared by Bio-Life Associates, Ltd. 536 p. 

100230 Clarkson, V.A.; Haines, R.G.; Hennsley, W.H.; et al. (1969) Report on 

Additional Field Tests with Temik 10G Aldicarb Pesticide on the 

Potential Hazard to Bobwhite Quail. (Unpublished study re- ceived Oct 

27, 1969 under 1016-EX-30; submitted by Union Carbide Corp., 
53 

Arlington, Va.; CDL:126506-B) 

100409 Haines, R. (1970) Field Evaluations of Potential Hazard of Temik 10G 

Aldicarb Pesticide to Valley Quail and Ring-necked Pheas- ants: Trial 

Two. (Unpublished study received Jan 25, 1978 under 1016-79; 

submitted by Union Carbide Corp., Arlington, VA; CDL:096734-K) 

 72-1 Acute Toxicity to Freshwater Fish 

MRID Citation Reference 

60555 or 

92405 

 Borash, A.J. (1965) Test Report on Union Carbide Agricultural Products. 

(Unpublished study received Jun 1, 1965 under unknown admin. no.; 

submitted by Union Carbide Corp., Arlington, Va.; CDL:128692-G) 

60556 Cope, O.B. (1964) Letter sent to Robert G. Harris dated Oct 30, 1964 

Toxicity of various pesticides to rainbow trout and blue- gill sunfish|. 

(U.S. Fish and Wildlife Service, Fish-Pesticide Research Laboratory; 

unpublished study; CDL:128692-H) 

61089 Borash, A.J.; Bryant, H.M., Jr. (1965) Test Report on Union Carbide 

Agricultural Products. (Unpublished study received Jun 10, 1965 under 

1016-EX-18; submitted by Union Carbide Corp., Arlington, Va.; 

CDL:126458-K) 

76065 Knott, W.; Beliles, R.P. (1966) UC-21149: Acute Toxicity in Sunfish. 

(Unpublished study received Jul 26, 1966 under 1016-69; prepared by 

Woodard Research Corp., submitted by Union Carbide Corp., Arlington, 

Va.; CDL:231174-A) 

76066 Woodard Research Corporation (1965) UC-21149: Safety Evaluation on 

Fish and Wildlife: (Bobwhite Quail and Rainbow Trout). (Unpublished 

study received Jul 26, 1966 under 1016-69; submitted by Union Carbide 

Corp., Arlington, Va.; CDL:231174-B) 

76067 Beliles, R.P.; Knott, W.; Wright, L. (1966) UC-21149 10%: Summary of 

Safety Evaluation on Fish and Wildlife. Summary of studies 231174-A 

and 231174-B. (Unpublished study received Jul 26, 1966 under 1016-

69; prepared by Woodard Research Corp., submitted by Union Carbide 

Corp., Arlington, Va.; CDL:231174-D) 

80706 Beliles, R.P.; Knott, W.; Wright, L. (1966) UC-21149: Safety Evaluation 

on Fish and Wildlife: (Bobwhite Quail and Rainbow Trout). (Unpublished 

study received Mar 2, 1967 under 7F0573; prepared by Woodard 

Research Corp., submitted by Union Carbide Corp., Charleston, W.Va.; 

CDL:090072-O) 

80707 Knott, W.; Beliles, R.P. (1966) UC-21149: Acute Toxicity in Sun- fish. 

(Unpublished study received Mar 2, 1967 under 7F0573; prepared by 

Woodard Research Corp., submitted by Union Carbide Corp., 

Charleston, W.Va.; CDL:090072-P) 

81883 Union Carbide Corporation (1965) Toxicity to Fish and Wildlife. 

(Compilation; unpublished study received May 10, 1965 under 5G0452; 

CDL:090494-B) 

100296 Clarkson, V.A.; Hensley, W.H. (1968) Temik Insecticide: Toxicity of 
54 

Temik, Temik Sulfoxide, and Temik Sulfone to Bluegill Sunfish: File No. 

10493. (Unpublished study received Jan 25, 1978 under 1016-79; 

submitted by Union Carbide Corp., Arlington, Va.; CDL:096727-B) 

102133 Schneider, C. (1979) The Acute Toxicity of Aldicarb Technical to the 

Rainbow Trout (Salmo gairdneri Richardson): UCES Proj. No. 11504-

14-03. (Unpublished study received Dec 12, 1979 under 1016-78; 

submitted by Union Carbide Corp., Arlington, VA; CDL:099120-C) 

102134 Schneider, C. (1979) The Acute Toxicity of Aldicarb Technical to the 

Bluegill Sunfish (Lepomis macrochirus Rafinesque): UCES Proj. No. 

11504-14-04. (Unpublished study received Dec 12, 1979 under 1016-

78; submitted by Union Carbide Corp., Arlington, VA; CDL:099120-D) 

102145 Borash, A.; Bryant, H. (1965) Test Report on Union Carbide Agricultural 

Products: (Toxicity to Goldfish). (Unpublished study received Sep 9, 

1965 under 1016-EX-24; CDL:126467-A) 

139863 or 

53353 

 Clarkson, V.A.; Hensley, W.H. (1968) Temik Insecticide: Toxicity of 

Temik, Temik Sulfoxide, and Temik Sulfone Bluegill Sunfish. Project No. 

111B32. (Unpublished study received Jan 18, 1977 under 1016-EX-37; 

submitted by Union Carbide Corp., Arlington, Va.; CDL:238153-C) 

5010817 Coppage, D.L. (1977) Anticholinesterase action of pesticidal 

carbamates in the central nervous system of poisoned fishes. Pages 93-

102, In Physiological Responses of Marine Biota to Pollutants, 

Proceedings of a Symposium; Nov, 1975, Milford, Connecticut. Edited 

by F.J. Vernberg, A. Calabrese, F.P. Thurberg and W.B. Vernberg. New 

York: Academic Press. 

40098001 Mayer, F.; Ellersieck, M. (1986) Manual of Acute Toxicity: Interpretation and Data Base for 410 Chemicals and 66 Species of 

Freshwater Animals. US Fish & Wildlife Service, Resource Pub- lication 

160. 579 p. 

44598601 Pickering, Q.; Gilliam, W. (1982) Toxicity of aldicarb and fonofos to the 

early-life-stage of the fathead minnow. Arch. Environ. Contam. Toxicol. 

11:699-702. 

45592113 Odin-Feurtet, M. (1999) Aldicarb: Acute Toxicity (96-Hour) to Bluegill 

Sunfish (Lepomis macrochirus) under Static Conditions: Lab Project 

Number: SA 99331. Unpublished study prepared by Rhone-Poulenc 

Agro. 74 p. 

45592115 Odin-Feurtet, M. (1998) Aldicarb Sulfoxide: Acute Toxicity (96 Hours) to 

Rainbow Trout (Oncorhynchus mykiss) under Flow-Through Conditions: 

Lab Project Number: SA 98081. Unpublished study prepared by RhonePoulenc Agro. 65 p. PC Code 110802 

45592117 McElligott, A. (1998) Aldicarb Sulfone: Acute Toxicity (96 Hours) to 

Rainbow Trout (Oncorhynchus mykiss) under Flow-Through Conditions: 

Lab Project Number: SA 98082. Unpublished study prepared by RhonePoulenc Agro. 64 p. Aldicarb Sulfone = PC Code 118201 

72-2 Acute Toxicity to Freshwater Invertebrates 

MRID Citation Reference 

107395 Vilkas, A. (1977) The Acute Toxicity of Aldicarb Technical to the Water 
55 

Flea ...: UCES Proj. #11504-14-01. (Unpublished study received Dec 

19, 1977 under 1016-69; submitted by Union Carbide Corp., Arlington, 

VA; CDL:096683-A) 

45592114 

72-3 Acute Toxicity to Estuarine/Marine Organisms 

MRID Citation Reference 

66341 U.S. Environmental Protection Agency, Environmental Research Laboratory (1981) Acephate, Aldicarb, Carbophenothion, DEF, EPN, 

Ethoprop, Methyl Parathion, and Phorate: Their Acute and Chronic 

Toxicity, Bioconcentration Potential, and Persistence as Related to 

Marine Environments: EPA-600/4-81-023. (Unpublished study) 

102036 Heitmuller, T. (1972) Letter sent to S. Ichikawa dated Jan 7, 1972 

Toxicity of Temik to grass shrimp|. (U.S. Environmental Protection 

Agency, Gulf Breeze Laboratory; unpublished study; CDL:096397-B) 

40228401 USEPA Gulbreeze Laboratory Study Reports- multiple species 

72-4 Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study 

MRID Citation Reference 

66341 U.S. Environmental Protection Agency, Environmental Research Laboratory (1981) Acephate, Aldicarb, Carbophenothion, DEF, EPN, 

Ethoprop, Methyl Parathion, and Phorate: Their Acute and Chronic 

Toxicity, Bioconcentration Potential, and Persistence as Related to 

Marine Environments: EPA-600/4-81-023. (Unpublished study) 

44598601 Pickering, Q.; Gilliam, W. (1982) Toxicity of aldicarb and fonofos to the 

early-life-stage of the fathead minnow. Arch. Environ. Contam. Toxicol. 

11:699-702. 

72-7 Simulated or Actual Field Testing 

MRID Citation Reference 

61078 Mulla, M.S. (1964) Letter sent to R.G. Haines dated Oct 20, 1964 

Information on toxicity of some compounds against mosquito fish|. 

(Unpublished study received Oct 20, 1964 under unknown admin. no.; 

prepared by Univ. of California--Riverside, Div. of Agricultural Sciences, 

Citrus Research Center and Agricultural Experiment Station, Dept. of 

Entomology, submitted by Union Car- bide Corp., Arlington, Va.; 

CDL:131936-A) 

 

141-1 Honey bee and Beneficial Insect Acute Toxicity 

117840 Johansen, C.; Eves, J. (1967) Bee Research Investigations, 1967. 

(Unpublished study received Oct 13, 1969 under 0F0897; prepared by 

Washington State Univ., submitted by Fisons Corp., Wilming- ton, MA; 

CDL:091551-H) 

149696 Johansen, C.; Mayer, D.; Eves, J.; et al. (1983) Pesticides and bees. 
56 

Environ. Entomology 12(5):1513-1518. 

91958 Ridgway, R.L.; Cowan, C.B. (1966) A Report on Laboratory and Field 

Studies on the Effect of Several Insecticides on Beneficial Arthropods in 

1966: ?Mobay| 20268. (U.S. Agricultural Research Service, Entomology 

Research Div., Cotton Insects Systemic Chemicals Investigations and 

Southwestern Cotton Insects In- vestigations; unpublished study; 

CDL:120463-D) 

36935 Atkins, E.L.; Greywood, E.A.; Macdonald, R.L. (1975) Toxicity of 

Pesticides and Other Agricultural Chemicals to Honey Bees: Laboratory Studies. By University of California, Dept. of Entomolo- gy. ?: UC, 

Cooperative Extension. (Leaflet 2287; published study.) 

142-3 Simulated or Actual Field Testing 

MRID Citation Reference 

102104 Atkins, E.; Kellum, D.; Atkins, K. (1977) Repellent Additives to Reduce 

Pesticide Hazards to Honey Bees: Maximizing the Effec- tiveness of 

Bees as Pollinators of Agricultural Crops: Project No. 3565-RR (W-139). 

Final rept. (Unpublished study received Jan 27, 1978 under 10182-17; 

prepared by Univ. of California-- Riverside, Citrus Research Center and 

Agricultural Experiment Station, Dept. of Entomology, submitted by ICI 

Americas, Inc., Wilmington, DE; CDL:096765-N) 

Non Guideline Selections 

53386 Spurr, H.W., Jr.; Sousa, A.A. (1974) Potential interactions of Al- dicarb 

and its metabolites on nontarget organisms in the envi- ronment. 

Journal of Environmental Quality 3(2):130-133. (Also In unpublished 

submission received jan 18, 1977 under 1016-EX- 37; submitted by 

Union Carbide Corp., Arlington, Va.; CDL: 228979-AA) 

93913 Westlake, G.E.; Bunyan, P.J.; Martin, A.D.; et al. (1981) Carbam- ate 

poisoning: Effects of selected carbamate pesticides on plasma enzymes 

and brain esterases of Japanese quail (Coturnix cotornix japonica). 

Journal of Agricultural and Food Chemistry 29(4):779-784. (Also In 

unpublished submission received Jan 26, 1982 under 239-2471; 

submitted by Chevron Chemical Co., Richmond, Calif.; CDL:246657-J) 

98468 Stauffer Chemical Company (1980) Comparison of Acute Oral Avian 

Toxicology between Dyfonate^(R)I 20-G Insecticide and Other Corn 

Granular Insecticides. (Unpublished study received Oct 24, 1980 under 

476-2028; CDL:243582-A) 

102197 Yu, C.; Kearns, C.; Metcalf, R. (1972) Acetylcholinesterase in- hibition 

by substituted phenyl N-alkyl carbamates. J. Agr. Fd. Chem. 20(3):537-

540. (Also In unpublished submission re- ceived Dec 11, 1979 under 

264-322; submitted by Union Carbide Agricultural Products Co., Inc., 

Ambler, PA; CDL:241454-C) 

102198 Hastings, F.; Main, A.; Iverson, F. (1970) Carbamylation and affinity 

constants of some carbamate inhibitors of acetylcholinesterase and 

their relation to analogous substrate constants. J. Agr. Food Chem. 
57 

18(3):497-502. (Also In unpublished submission received Dec 11, 1979 

under 264-322; submitted by Union Carbide Agricultural Products Co., 

Inc., Ambler, PA; CDL:241454-D) 

102199 Reiner, E. (1971) Spontaneous reactivation of phosphorylated and 

carbamylated cholinesterases. Bull Wld Hlth Org. 44:109-112. 

(Published study; CDL:241454-E) 

148686 Ross, D.; Roberts, N.; Cameron, D. (1978) A Comparison of the Palatability to the Ring-necked Pheasant of Three Formulations of Temik 

10 G with Other Granular Pesticides: UNC/69C/78938. Un- published 

study prepared by Huntingdon Research Centre. 23 p. 

148687 Ross, D.; Roberts, N.; Cameron, D. (1978) A Comparison of the Palatability to the Zebra Finch of Two Formulations of Temik: UNC 69 

G/78398. Unpublished study prepared by Huntingdon Research Centre. 

16 p. 

148688 Ross, D.; Roberts, N.; Cameron, D. (1978) A Comparison of the Palatability to the Ring-necked Pheasant of Two Formulations of Te- mik: 

UNC 69 G/78399. Unpublished study prepared by Huntingdon 

Research Centre. 14 p. 

148689 Ross, D.; Roberts, N.; Cameron, D. (1979) The Effect of Granule Size 

on the Toxic Hazard to Passeriformes of Temik 10G: UNC 69B/ 78721. 

Unpublished study prepared by Huntingdon Research Cen- tre. 16 p. 

148690 Stickel, W. (1979) Letter sent to R. Back dated May 29, 1979: [Comments on "Report on palatability studies and trials regarding the acute 

toxicity of the plant protection products Temik 10 G and Temik 10 GGF 

(gypsum) with Japanese quails, chickens and sparrows"]. Prepared by 

the US Fish and Wildlife Service, Pa- tuxent Wildlife Research Center. 3 

p. 

148694 Spencer, D. (1985) A Review of the Research Conducted on the Toxicity and Potential Hazard of Granular Formulations of Aldicarb (Temik) to 

Bird Life. Unpublished study. 32 p. 

148708 Relton, J. (1970) Wild Life Survey: Temik 10G Aldicarb Pesticide on 

Sugar Beets: Suffolk, England, 1970. Unpublished study. 11 p. 

41255501 U. S. Fish and Wildlife Service (1989) Biological Opinion on Selected 

Pesticides. Unpublished study. 891 p. 

41377100 U.S. Fish and Wildlife Service (1990) Submission of Biological Opinion 

Data for Selected Pesticides. Transmittal of 1 study. 

41377101 U. S. Fish and Wildlife Service (1989) Biological Opinion Log on 

Selected Pesticides. Unpublished study. 677 p. 

 1982 Biological Opinion 

41708603 Hobson, J. (1990) Aldicarb: Response to the Review by the Ecologi- cal 

Effects Branch of the 1987 Temik Terrestrial Vertebrate Field Study. 

Unpublished study prepared by Rhone-Poulenc Ag Co. 20 p. 

41708604 Kendall, R. (1990) Behavior, Survivability and Biochemical Response of 

Wild Mourning Doves (Zenaida macroura) Dosed with Aldicarb: Final 

Research Report Phase I: Lab Project Number: 08035. Unpub- lished 
58 

study prepared by Clemson Univ., Institute of Wildlife and Environ. 

Toxicology. 29 p. 

42316001 Smith, K. (1992) Clinical Necropsy report on three red-tailed hawks 

found near Edgefield, South Carolina. Prepared by Univ. of Ga., College 

of Veterinary Med. 2 p. 

42316100 Univ. of Georgia (1992) Submission of an incident report involving 

Temik in the wildlife kill of a gray fox. Data submitted under FIFRA 

6(a)(2). Transmittal of 1 study. 

42316101 Smith, K. (1992) Clinical Necropsy Report on a Gray Fox Found near 

Edgefield, South Carolina. Unpublished study prepared by Univ. of 

Georgia, College of Veterinary Med. 2 p. 

42316200 Univ. of Georgia (1992) Submission of an incident report involving 

Temik in a wildlife kill of raccoons. Data submitted under FIFRA 6(a)(2). 

Transmittal of 1 study. 

42316201 Smith, K. (1992) Clinical Necropsy Record on a Raccoon Found near 

Edgefield, South Carolina. Unpublished study prepared by Univ. of Ga., 

College of Veterinary Med. 2 p. 

42316500 Rhone-Poulenc Ag. Co. (1992) Submission of incident reports under 

FIFRA 6(a)(2) Status (Adverse effects and incident report) to support 

the reregistration of Temik (Aldicarb) pesticide. Transmittal of 1 study. 

42316501 Davis, W. (1992) Letter Sent to S. Haddad dated May 11, 1992: ?Death 

of dogs and cats in two separate incidents related to Temik (Aldicarb)|. 2 

p. 

46655401 Moore, D.; Thompson, R.; Purbrick, S. (2005) Problem Formulation for 

the Refined Aquatic Risk Assessment of Aldicarb. Project Number: 

201373, 88380. Unpublished study prepared by Cantox Environmental 

Inc. 31 p. 

46655402 Moore, D.; Purbrick, S.; Thompson, R. (2005) Problem Formulation for 

the Refined Wildlife Risk Assessment of Aldicarb. Project Number: 

201374, 88380. Unpublished study prepared by Cantox Environmental 

Inc. 37 p. 

46792601 Hall, L. (2006) Temik Brand 15G Aldicab Pesticide Crop and 

Geographical Usage Information (A Reference Provided for an 

Endangered Species Assessment of Aldicarb). Project Number: 

G201481. Unpublished study prepared by Bayer Cropscience LP. 76 p. 

46796102 Moore, D.; Thompson, R.; Purbrick, S. (2006) Refined Aquatic Risk 

Assessment for Aldicarb. Project Number: 201482. Unpublished study 

prepared by Cantox Environmental Inc. 234 p. 

46796103 Moore, D.; Purbrick, S.; Teed, R.; et. al. (2006) Refined Wildlife Risk 

Assessment for Aldicarb. Project Number: 201483, 88390. Unpublished 

study prepared by Cantox Environmental Inc. 493 p. 

46873101 Best, L.; Brewer, L.; Klaine, S.; et. al. (2006) Refined Ecological Risk 

Assessment for Aldicarb Expert Peer Review Panel Process and 

Comments. Project Number: EPR/32306. Unpublished study prepared 

by Bayer CropScience LP. 10 p. 

47124601 Fisher, D.; Ramanarayanan, T.; Moore, D.; et al. (2007) Effects 
59 

Determination for California Red-Legged Frog Potentially Exposed to 

Aldicarb. Project Number: 88380, 201692. Unpublished study prepared 

by Cantox Environmental, Inc. 138 p. 

47164600 Croplife America (2007) Submission of Environmental Fate and 

Exposure and Risk Data in Support of the Preservation of the California 

Red Legged Frog. Transmittal of 2 Studies. 

47164601 Moore, D.; Breton, R.; Rodney, S.; et al. (2007) Generic Problem 

Formulation for California Red-Legged Frog. Project Number: 89320, 

05232007. Unpublished study prepared by Cantox Environmental Inc. 

87 p. 

47164602 Holmes, C.; Vamshi, R. (2007) Data and Methodology Used for Spatial 

Analysis of California Red Legged Frog Observations and Proximate 

Land Cover Characteristics. Project Number: 3152007, WEI/252/03. 

Unpublished study prepared by Waterborne Environmental, Inc. (WEI). 

19 p. 

101909 Union Carbide Corp. (1969) Temik Aldicarb Pesticide: The Potential 

Hazard from Ingestion of Treated Plant Tissue. (Unpublished study 

received Nov 5, 1969 under 1016-69; CDL:024310-F) 

102199 Reiner, E. (1971) Spontaneous reactivation of phosphorylated and 

carbamylated cholinesterases. Bull Wld Hlth Org. 44:109-112.

(Published study; CDL:241454-E) 

42243301 W. Davis (1992) Letter Sent to S. Haddad dated February 19, 1992: 

Concerning deaths of an ocelot, two oppossums, and four raccoons at 

Atascosa Wildlife Refuge in Rio Hondo, Texas|. Prepared by RhonePoulenc Ag. Co. 1 p. 

53383 or 

102053 or 

104568 

 Romine, R.R.; Meeker, R.L. (1973) Accumulation of Aldicarb Residues 

in Fish Tissue from Chronic Exposure to Aldicarb, Aldicarb sulfoxide 

and Aldicarb sulfone in Aquaria Water: Project No. 111A13. 

(Unpublished study received Jan 18, 1977 under 1016-EX-37; 

submitted by Union Carbide Corp., Arlington, Va.; CDL:228979-X) 
60 

Appendix A. Ecological Effects Data 

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. Mammalian 

acute studies are usually limited to Norway or New Zealand 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 the aquatic 

environment. The following information was taken from previous assessments and updated if 

recent studies were submitted. 

Toxicity to Terrestrial Animals 

Birds, Acute and Subacute

The acute oral LD50 is 1.0 mg/kg-bw for aldicarb, and 33.5 mg/kg-bw for aldicarb sulfone. The 

most sensitive species tested for both aldicarb and aldicarb sulfone is the mallard duck. Aldicarb 

and aldicarb sulfone are categorized as very highly toxic and highly toxic to avian species on an 

acute oral basis, respectively (MRID 107398). 

The most sensitive species tested on a subacute 5-d dietary basis for both aldicarb and aldicarb 

sulfone is the bobwhite quail. The 5-d LC50 is 71 ppm for aldicarb, and 5706 ppm for aldicarb 

sulfone (or sulfocarb). Aldicarb and aldicarb sulfone are categorized as very highly toxic and 

practically nontoxic to avian species, respectively (MRID 00102132 & 1096727). 

Birds, Chronic 

The avian reproduction studies submitted by the registrant were both classified as supplemental 

(MRIDs 48156905 & 48198801). 

MRID 48156905 is a one-generation reproductive toxicity study involving dietary exposures of 

Northern bobwhite quail (Colinus virginianus) to aldicarb. Aldicarb was administered to the 

birds in the diet at nominal concentrations of 0 (vehicle control), 2, 10, and 50 mg ai/kg diet 

(corrected for purity). Mean-measured concentrations were <0.2 (<LOQ, control), 1.8, 8.3, and 

43 mg ai/kg diet, respectively. This study is scientifically sound but classified supplemental 

because of small cage sizes and because the test was unable to detect up to 25% difference in 

treatment animal endpoints compared to controls. This study may not be used to fulfill the 

guideline requirement. Although none of the endpoints in the treated groups displayed 

statistically significant differences compared to controls, several of the endpoints had 10-25% 

difference in the two highest treatments. These endpoints include: number of eggs laid/pen, 

number of eggs set/pen, number of viable embryos/pen, number of live embryos/pen, number of 

hatchlings/pen, hatchling survival/pen. In addition, adult body weight gain was also decreased in 

these treatments. The reviewer concluded that these differences may be biologically significant. 

Therefore, the NOAEC of this study is set to the lowest test concentration (i.e., 1.8 mg a.i./kgdiet) and the LOAEC is 8.3 mg a.i./kg-diet. 
61 

MRID 48198801 is a one-generation reproductive toxicity study involving dietary exposures of 

mallard duck (Anas platyrhynchos) to aldicarb. Aldicarb was administered to the birds in the 

diet at nominal concentrations of 0 (vehicle control), 3, 15, and 75 mg ai/kg diet (corrected for 

purity). Mean-measured concentrations were <1.0 (<LOQ, control), 3, 15, and 72 mg ai/kg diet, 

respectively. There were slight, but statistically-significant (p<0.05) effects on several endpoints 

at the 15 mg ai/kg diet level; however, these effects were not observed at the next highest level 

(i.e., 72 mg a.i./kg diet). At the 15 mg a.i./kg diet level, there was a significant (p=0.016) 

increase in the number of eggs cracked, with an average of 0.25 eggs cracked per pen in the 

control versus 1.31 eggs per pen in the 15 mg ai/kg diet group. No other treatment level 

exhibited a higher incident of cracked eggs, but the 15 mg ai/kg diet level continued to exhibit 

reductions in the number of eggs set to eggs laid (p=0.010; 3.5% reduction from control), ratio of 

14-day survivors to number hatched (p=0.04; 0.6% reduction), and hatchling weights (p=0.004; 

5.8% reduction). No other treatment-related effects were observed at any concentration level for 

any adult, reproductive, or offspring parameter. Despite the observation of statistically 

significant effects at the 15 mg ai/kg level, the reviewer concluded that these effects were not 

related to the test substance because similar effects were not observed at the next highest 

treatment level (i.e., 72 mg a.i./kg diet), which was a factor of 5 greater than the level were 

effects were observed. This study is scientifically sound; however, it does not satisfy the 

guideline requirement for a mallard duck (Anas platyrhynchos) reproductive toxicity study. This 

study is classified supplemental because a LOAEC was not established in the study and the study 

report does not indicate the maximum field residue that would be expected based on application 

rates of aldicarb. Therefore, it is unknown if the highest level tested was an appropriate level to 

approximate the maximum expected field residues. 

Mammals, Acute

Rat toxicity values obtained from the Agency's Health Effects Division (HED) substitute for wild 

mammal testing. Aldicarb is categorized as very highly toxic to small mammals on an acute oral 

basis with a rat LD50 of 0.9 mg/kg-bw (MRID 00057333). 

Mammals, Chronic

In a 2-generation reproduction study reviewed by HED (MRID 42148401), rats were exposed to 

aldicarb in their diet at concentrations of 0, 2, 5, 10, and 20 ppm. Exposure consistently led to 

decreased dam body weight gain (parental LOAEL = 0.7 - 0.9 mg/kg-bw; NOAEL = 0.4 mg/kgbw). Aldicarb treatment also caused lower survivability and pup weights in offspring of all 

litters (reproductive LOAEL = 1.4 - 1.7 mg/kg-bw; NOAEL = 0.7 - 0.9 mg/kg-bw). These 

toxicity values are similar to the acute oral LD50 mammalian values and suggest that mammals 

that survive acute aldicarb exposure may suffer adverse reproductive effects from chronic 

exposure. 

Beneficial Insects

A honey bee acute contact study using the TGAI is not required for aldicarb due to its granular 

formulation. However, aldicarb is categorized highly toxic to bees on an acute contact basis with 

an LD50 of 0.285 ug/bee (MRID 00036935). It is recognized that potential honey bee exposure 

may occur due to the systemic nature of aldicarb. Because of its granular formulation, it is 
62 

unlikely that there is a direct contact exposure scenario for honey bees; however, these and other 

beneficial insects could be exposed to aldicarb and aldicarb residues through contact with plants 

and soil. 

Earthworms

Soil-dwelling invertebrates, such as earthworms, can play important roles in maintaining soil 

fertility and facilitating organic matter degradation, as well as an important food source for birds 

and mammals. A study by Mosleh et al (2003) demonstrated an earthworm (Aporrectodea 

caliginosa) 28-day LC50 of 0.68 ppm. 

Toxicity to Terrestrial Plants 

Terrestrial plant testing is required for pesticides other than herbicides if data from the literature 

indicate that a pesticide is phytotoxic. A tier I seedling emergence study (MRID 4704401) is 

classified supplemental and cannot be used to fulfill the guideline requirement for 850.4100. 

This study is upgradable if a Tier II seedling emergence study is submitted for ryegrass and 

tomato. 

Summary of review of MRID 47904401 

The effect of Temik 15 G (AI: Aldicarb) on the seedling emergence of monocot (corn, Zea mays; 

oat, Avena sativa; onion, Allium cepa; and ryegrass, Lolium perenne) and dicot (cucumber, 

Cucumis sativus; oilseed rape, Brassica napus; sugarbeet, Beta vulgaris; soybean, Glycine max; 

sunflower, Helianthus annuus; and tomato, Lycopersicon esculentum) crops was studied at 

nominal concentrations of 0 (negative control) and 75 kg product/ha, which is equivalent to 11.5 

kg ai/ha (10.3 lb ai/A). The growth medium used in the seedling emergence test was a mixture 

of natural soil (silt loam) and washed sand; pH 7.24, organic carbon 0.63%. On day 21, the 

surviving plants per pot were recorded and cut at soil level for measuring the plant height and 

dry weight. 

The most sensitive monocot species was ryegrass, with a 12 and 44% difference in shoot length 

and weight, respectively, compared to the control. The most sensitive dicot species was tomato, 

with a 28 and 25% difference in shoot length and weight, respectively, compared to the control. 

Phytotoxic effects, including stunting and necrosis, were observed in ryegrass and tomatoes. 

Based on the observance of >25% effects in ryegrass and tomato, a tier II study consistent with 

OCSPP guideline 850.4225 and using these two species is necessary to fulfill the guideline 

requirement for 850.4100. The Tier I studies with ryegrass and tomato are considered 

supplemental. The data from the Tier I studies with corn, oat, onion, cucumber, oilseed rape, 

soybean, sugarbeet and sunflower are all considered acceptable. Overall, this toxicity study is 

classified supplemental and does not satisfy the guideline requirement for a seedling emergence 

toxicity study because >25% effects were observed in two species (i.e., ryegrass and tomato) and 

tier II studies have not been submitted for those species. 
63 

Toxicity to Freshwater Animals

Freshwater Fish, Acute

Aldicarb

Since the 96-h LC50 values ranged from 52 to 110 ppb ai, aldicarb is categorized as very highly 

toxic to highly toxic to freshwater fish on an acute basis. The most sensitive of these results was 

the 52 ppb ai for the bluegill sunfish (Mayer and Ellersieck 1986) conducted under static 

conditions. A supplemental acute toxicity test conducted under static conditions reported a 96-h 

LC50 for aldicarb of 110 ppb ai for juvenile bluegill sunfish. Because of the static conditions, it 

is likely this value reflects contribution of parent aldicarb and its degradates. The bluegill sunfish 

96-h LC50 of 52 ppb ai was chosen to calculate acute risk quotients from exposure to aldicarb 

because it is the most sensitive endpoint of the 96-h LC50 values. There was an acute value for 

fathead minnow exposed to aldicarb found in the public literature but it was only for a 48 hour 

study, therefore it is likely an underestimate of aldicarb toxicity to this species at 96 hours and is 

therefore classified as supplemental information. 

Acute Toxicity Endpoints for Freshwater Fish 

Species Endpoint (ppb ai) MRID/Reference

Aldicarb

Bluegill sunfish 96-h LC50 = 52 ppb ai MRID 40098001and MRID3503 

(Mayer and Ellersieck 1986) 

Rainbow trout 96-h LC50 = 560 ppb ai MRID 40098001and MRID 

3503 (Mayer and Ellersieck 

Fathead minnow 48-hr LC50 = 8,860 ppb ai Moore. et al. 1998 

(Supplemental information as 

this is only a 48-h study) 

Aldicarb sulfoxide

Rainbow trout 96-h LC50 = 7,140 ppb ai MRID 45592115

Aldicarb sulfone

Rainbow trout 96-h LC50 = 42,000 ppb ai Acc# 096727 (Anonymous 

1976) 

Rainbow trout 96-h LC50 > 106,000 ppb ai MRID 45592117 

Aldicarb sulfoxide

A flow through acute toxicity test using the degradate aldicarb sulfoxide was conducted on 

rainbow trout. A 96-h LC50 of 7,140 ppb was reported which is classified as moderately toxic 

(MRID 45592115). 

Aldicarb sulfone
64 

An acute toxicity test conducted on rainbow trout using the degradate aldicarb sulfone had a 96-h 

LC50 of 42,000 ppb ai. This is characterized as slightly toxic [Acc# 096727 (Anonymous 1976)]. 

A flow through acute toxicity test using aldicarb sulfone had a 96-h LC50 greater than 106,000 

ppb ai for rainbow trout, which is characterized as practically non toxic (MRID 45592117). 

Based on the acute toxicity studies for freshwater fish, the relative toxicity relationship is: 

aldicarb>aldicarb sulfoxide> aldicarb sulfone.

Freshwater Fish, Chronic

Aldicarb

A freshwater fish early life-stage test using aldicarb (99% ai) has been conducted with the 

fathead minnow. The NOAEC was 78 ppb ai and the LOAEC was 156 ppb ai. The most 

sensitive endpoint was the survival of larvae-juveniles after 30-days exposure (MRID 44598601 

also known as BOWOAL07/4 (Q.H. Pickering and W.T. Gilliam 1982)). However, according to 

the acute freshwater fish data the bluegill sunfish was the most sensitive freshwater fish tested 

with a 96-h LC50 of 52 ppb ai. This 96-h LC50 of 52 ppb ai is lower than the NOAEC of 78 ppb 

ai for the fathead minnow, indicating that the bluegill is much more sensitive to aldicarb than the 

fathead minnow. Therefore, a screening level chronic RQ for fish cannot be calculated using the 

fathead minnow chronic NOAEC directly. However since both a supplemental acute (48-h 

LC50= 8,860 ppb ai; Moore. et al. 1998) and acceptable chronic (NOAEC = 78 ppb ai) aldicarb 

value exist for fathead minnow, an acute-to-chronic ratio (ACR) can be calculated for this 

species and then used to determine an estimated NOAEC for the bluegill sunfish. 

The ACR for the fathead minnow of 114 is calculated by dividing the fathead minnow 48-hr 

EC50 of 8,860 ppb ai by the fathead chronic NOAEC of 78 ppb ai. The 96-h LC50 of 52 ppb ai 

for the bluegill sunfish is then divided by the ACR of 114 which results in an estimate of the 

chronic NOAEC for the bluegill sunfish of 0.46 ppb ai. A 48-h LC50 value was used to calculate 

the ACR rather than a 96-h LC50 because none was available, this potentially over estimates the 

ACR for fathead minnow. Additionally, a robust estimate of an ACR (i.e., geometric mean of 

ACRs for at least three fish species with at least one coldwater and one warmwater species) for 

aldicarb could not be calculated because only one fish species, the fathead minnow, had both 

acute and chronic endpoints available for determination of an ACR. While a more robust 

estimate of the ACR is desirable, the use of the fathead minnow ACR is a reasonable estimate 

but may be either a slight over or underestimate of ACR for fish. 

Chronic Toxicity Endpoints for Freshwater Fish 

Species Endpoint MRID/Reference

Aldicarb

Fathead minnow fish early life stage NOAEC 

= 78 ppb ai 

MRID 44598601 also known as 

BOWOAL07/4 (Q.H. Pickering and W.T. 

Gilliam 1982) 
65 

Bluegill sunfish Estimated NOAEC = 0.46 

ppb ai 

96-h LC50 for bluegill sunfish (52 ppb ai) 

divided by ACR (fathead minnow 48-h 

EC50 of 8860 ppb ai divided by NOAEC 

of 78 ppb ai) 

Freshwater Invertebrates, Acute

Aldicarb

A Daphnia magna core study determined the 48-h EC50 to be 410 ppb ai (Acc #096683, also 

known as BOWOAL08 and MRID 107395 (Vilkas 1977), categorizing aldicarb as highly toxic 

to aquatic freshwater invertebrates on an acute basis. Because this test was conducted under 

static rather than flow-through conditions, it is likely that this value reflects the contributions of a 

mixture of parent aldicarb and various degradates. A supplemental study from the literature 

reported the 48-h LC50 of aldicarb to Daphnia magna, Aedes aegypti, Atermia sp., and Aedes 

taeniorhynchus as 75, 290, 5460, and 150 ppb ai respectively, in 48 hour static tests (Song et al., 

1997). A supplemental study from open literature also concluded that aldicarb was very-highly 

toxic to Daphnia magna with a reported 48-h EC50 of 583 ppb (Moore. et al. 1998). This same 

study reported a 48-h EC50 of 3990 ppb for Hyalella azteca (categorized as moderately toxic) 

and a reported 48-h EC50 of 20 ppb for Chironomus tentans. A supplemental study obtained 

from open literature (Foran et al. 1985) determined the 48-h EC50 of juvenile Daphnia laevis to 

be 65 ppb and 51 ppb for adult Daphnia laevis categorizing aldicarb as very highly toxic. 

Because Moore et al. (1998) is classified as a supplemental study of high quality, the 48-h 

Chironomus tentans EC50 value of 20 ppb will be used in the risk characterization. 

Aldicarb sulfoxide

Foran et al. 1985 also found that aldicarb sulfoxide is also very highly toxic to Daphnia laevis, 

with a 48-h EC50 of 57 ppb for juveniles and 43 ppb for adults. Thus, aldicarb sulfoxide toxicity 

to freshwater invertebrates appears to be similar in toxicity to aldicarb. A supplemental static 

acute toxicity test was performed using the degradate aldicarb sulfoxide with the test species 

Daphnia magna. The 48-h EC50 was 696 ppb, which is classified as highly toxic to daphnids 

(MRID 45592114). 

Aldicarb sulfone

Based on a core study, the 48-h EC50 for aldicarb sulfone is 280 ppb for Daphnia magna which 

is categorized as highly toxic to freshwater invertebrates on an acute basis [Acc# 096727 

(Anonymous 1976) ]. Foran et al. (1985) also found that the toxicity of aldicarb sulfone to 

daphnids is in the highly toxic category (juvenile 48-h EC50=556 ppb and adult 48-h EC50=369 

ppb). 

Based on the acute toxicity studies for freshwater invertebrates, the relative toxicity relationship 

is: aldicarb aldicarb sulfoxide > aldicarb sulfone. 
66 

Acute Toxicity Endpoints for Freshwater Invertebrates 

Species Endpoint MRID/Reference

Aldicarb

Daphnia magna 48-h EC50 = 410 ppb Acc #096683, also known as 

BOWOAL08 and MRID 

107395 (Vilkas 1977), 

Daphnia magna 48-hr LC50 = 75 ppb Song et al., 1997 

Aedes aegypti 48-hr LC50 = 290 ppb Song et al., 1997 

Atermia sp. 48-hr LC50 = 5460 ppb Song et al., 1997 

Aedes taeniorhynchus 48-hr LC50 = 150 ppb Song et al., 1997 

Daphnia magna 48-hr EC50 = 583 ppb Moore. et al. 1998 

Hyalella azteca 48-hour EC50 = 3990 ppb Moore. et al. 1998 

Chironomus tentans 48-hour EC50 = 20 ppb Moore. et al. 1998 

Daphnia laevis (juvenile) 48 hr EC50 =65 ppb Foran et al. 1985 

Daphnia laevis (adult) 48 hr EC50 = 51 ppb Foran et al. 1985 

Aldicarb sulfoxide

Daphnia magna 48-h EC50 = 696 ppb MRID 45592114 

Daphnia laevis (adult) 48 hr EC50 = 43 ppb Foran et al. 1985 

Daphnia laevis (juvenile) 48 hr EC50 =57 ppb Foran et al. 1985 

Aldicarb sulfone

Daphnia magna 48-h EC50 = 280 ppb Acc# 096727 (Anonymous 

1976) 

Daphnia laevis (adult) 48-h EC50=369 ppb Foran et al. (1985) 

Daphnia laevis (juvenile) 48-h EC50=556 ppb Foran et al. (1985) 

Qualitative Studies

Midge, Chironomus riparius Symptoms of intoxication Kallander et al. 1997 

Midge, Chironomus riparius 24-hr LC50 (water only) = 

9.9 ppb 

24-hr LC50 (spiked water) = 

10.0 ppb, 

24-hr LC50 (spiked sediment) 

= 26.7 ppb 

Lydy et al. 1990 

Gammarus italicus Goedm. 96-hr LC50 = 420 ppb Pantani et al. 1997 
67 

Species Endpoint MRID/Reference

Echinogammarus tibaldii 

Pink. 

96-hr LC50 = 220 ppb Pantani et al. 1997 

Midge Chironomus riparius 24 hr EC50 value = 23 ppb Sturm and Hansen 1999 

Daphnid Daphnia magna 24 hr EC50 value = 227.6 ppb Sturm and Hansen 1999 

Aedes taeniorhynchus 48-hr LC50 = 150 ppb 

(hyperosmotic condition) 

72-hr LC50=200 ppb ( 

isosmotic conditions) 

Song and Brown 1998 

Artemia sp. 48-hr LC50 = 5460 ppb ( 

hyperosmotic) 

72-hr LC50=17250 ppb 

(isosmotic conditions)

Song and Brown 1998 

Pond snail Lymnaea 

acuminata

48-hr LC50 = 20000 ppb Singh and Agarwal 1981 

Apple snail Pila globosa 

Swainson 

48-hour LC50 value could not 

be determined 

Singh and Agarwal 1981 

Midge Chironomus riparius None Fisher et al. 1993 

Midge Chironomus riparius 24-hour LC50 values ranged 

from 17-28 ppb at pH 4-8 

Suorsa and Fisher 1986 

Aldicarb sulfoxide 

Daphnia magna EC50 = 696 ppb MRID 45592114 

Daphnia laevis (adult) 48 hr EC50 = 43 ppb Foran et al. 1985 

Daphnia laevis (juvenile) 48 hr EC50 =57 ppb Foran et al. 1985 

Aldicarb sulfone 

Daphnia magna EC50 = 280 ppb Acc# 096727 (Anonymous 

1976) 

Daphnia laevis (adult) EC50=369 ppb Foran et al. (1985) 

Daphnia laevis (juvenile) EC50=556 ppb Foran et al. (1985) 

Freshwater Invertebrate Qualitative Studies

Using the database ECOTOX to identify additional data from the open literature, several 

supplemental studies were identified that can be used qualitatively to discuss the effects of 

aldicarb on freshwater invertebrates. These studies were not appropriate for quantitative use in 

calculation of risk quotients (see Appendix L for more detailed explanations). 
68 

A one day test identified aldicarb as very highly toxic to the midge and daphnid on an acute 

toxicity basis under static conditions. The 24-h EC50 value was reported to be 23 ppb a.i. for the 

midge and 227.6 ppb a.i. for the daphnid (Sturm and Hansen 1999). 

Several studies examined the effects of aldicarb to freshwater invertebrates and the effects of 

pulse dosing, pH, and different modes of exposure. In a pulsed exposure test, Kallander et al. 

(1996) studied midges (Chironomus riparus) exposed to aldicarb under static conditions. 

Midges exposed to aldicarb for two, pulsed 1-hour periods with a recovery period in clean water 

for 6 or more hours showed significantly fewer symptoms of intoxication than those exposed 

continuously for 2 hours. This indicates that continuous exposure to aldicarb from runoff events 

with no recovery time would exacerbate the symptoms of intoxication for freshwater 

invertebrates. 

The 24 hour acute toxicity of aldicarb to Chironomus riparus was studied under static conditions 

at pH 4, 6, and 8 (Suorsa and Fisher 1986). The 24-h LC50 values ranged from 17-28 ppb for 

aldicarb at pH 4-8. Toxicity of aldicarb to midges did not differ significantly as a function of 

pH. 

A 24 hour static study by Lydy et al (1990) evaluated three modes of exposure of aldicarb to 

Chironomus riparius: treated water only with no sediment (water only); treated water with 

untreated sediment (spiked water); and treated sediment with untreated water (spiked sediment). 

The reported 24-h LC50 for the water only, spiked water, and spiked sediment treatments were 

9.9, 10.0 and 26.7 ppb respectively, which classifies aldicarb as very highly toxic to C. riparius 

on an acute toxicity basis for all three routes of exposure. In addition, these tests indicate that the 

water exposure pathways produce more sensitive endpoints than sediment exposure. This 

affirms the use of acute aquatic toxicity tests using aldicarb for freshwater invertebrates to be the 

most sensitive route of exposure. 

Fisher et al. 1993 studied the toxicity of aldicarb to the midge with and without sediment. Five 

molecular descriptors (molecular volume, Henry’s law constant, n-octanol/water partition 

coefficient, molecular connectivity, and linear solvation energy) were used in regression analysis 

as potential predictors of pesticide activity. Quantitative structure activity relationships indicate 

sediment sorption plays a large role in the ultimate toxicity of aldicarb to the midge. 

Several studies were identified that deal with species not normally tested in registrant submitted 

studies. These studies classified aldicarb in a range of slightly toxic to highly toxic. The 96-hr 

acute toxicity of aldicarb to Gammarus italicus Goedm and Echinogammarus tibaldii Pink was 

studied under static conditions (Pantani et al. 1997). The 96-h LC50 value was determined to be 

420 ppb a.i. and 220 ppb a.i., respectively, which categorizes aldicarb as highly toxic on an acute 

toxicity basis. 

The 240-hr acute toxicity of aldicarb to the pond snail Lymnaea acuminata and the apple snail 

Pila globosa Swainson was studied under static conditions (Singh and Agarwal 1981). Paralysis 

was observed in the test organisms within 24 hours of exposure even though the animals 

remained alive for varying lengths of time; no mortality was observed in the control group. The 

48-h LC50 value was 20000 ppb a.i., which categorizes aldicarb as slightly toxic to L. acuminata

on an acute toxicity basis. The 48-h LC50 value could not be determined for the apple snail 

within the range of doses tested. The LC50 values from 72 hours to 240 hours ranged from 
69 

210000-78000 ppb, which categorizes aldicarb as practically non-toxic to slightly toxic to P. 

globosa on an acute to subchronic toxicity basis. 

The 48-h hyperosmotic and 72-hour isosmotic acute toxicities of aldicarb to the mosquito Aedes 

taeniorhynchus and brine shrimp Artemia sp. were studied under static conditions (Song and 

Brown 1997). Mosquito and nauplii larvae were exposed to the test material at two different 

salinities, hyperosmotic and isosmotic. Under hyperosmotic conditions, the reported Aedes 48-

hour LC50 was 150 ppb a.i and the Artemia 48-hour LC50 was 5460 ppb a.i. Aldicarb is thus, 

classified as highly toxic to Aedes and moderately toxic to Artemia sp. Under isosmotic 

conditions, the reported 72-hour LC50 was 200 ppb a.i. for Aedes (highly toxic) and the 72-hour 

LC50 was 17250 ppb a.i. for Artemia (slightly toxic).

Freshwater Invertebrate, Chronic

Aldicarb

The chronic risk to freshwater invertebrates is based on the estuarine/marine chronic study using 

Mysidopsis bahia. The reason for using this endpoint is based on the memorandum dated 

December 14, 1993, from A. Maciorowski, EFED to P. Poli, SRRD (D196663): “EEB has 

previously received and reviewed a valid Mysid shrimp chronic toxicity study that resulted in a 

calculated MATC of 1-1.5 ppb. Since the acute data indicates that the Mysid shrimp is more 

sensitive to aldicarb than Daphnia magna (Mysid shrimp LC50 = 16 ppb, Daphnia magna LC50 = 

410.7 ppb) and EEB does have valid Mysid shrimp chronic toxicity data, EEB is willing to waive 

the requirement for the Guideline 72-4(b) Freshwater Invertebrate Life Cycle Study. However, as 

a result all aquatic risk assessments utilizing invertebrate chronic toxicity data will be based on 

the Mysid shrimp data.” The mysid shrimp NOAEC is 1.0 ppb. 

A supplemental chronic toxicity study was submitted that evaluated the effect of aldicarb (99.9% 

a.i.) on Daphnia magna. An EC50 of 90 ppb, NOAEC of 20 ppb, and LOAEC of 60 ppb were 

reported for mortality and immobilization. An EC50 with a range of 190 to 570 ppb, NOAEC of 

190 ppb and LOAEC greater than 190 ppb were reported for reproductive effects. The most 

sensitive endpoint was reproductive effects (MRID 45592112). This study is classified as 

supplemental and is not upgradeable to core due to the study’s deviations. 

Chronic Toxicity Endpoints for Freshwater Invertebrates

Species Endpoint MRID/Reference

Aldicarb

Daphnia magna NOAEC = 20 ppb MRID 45592112 
70 

Toxicity to Estuarine and Marine Animals

Estuarine and Marine Fish, Acute

Aldicarb

Based on results from the preferred test species, sheepshead minnow, 96-h LC50 values range 

from 41 to 170 ppb. Therefore, aldicarb is categorized very highly to highly toxic to 

estuarine/marine fish on an acute basis. The most sensitive estuarine/marine fish species tested 

was the sheepshead minnow with a 96-h LC50 of 41 ppb [MRID 40228401 (U.S. EPA 1986)]. A 

supplemental study obtained from open literature (Landau and Tucker 1984) found a similar 

magnitude value for a snook (Centropomus undecimalis) embryo/larva bioassays with a 36-hr 

LC50 of 40 ppb. After 96-hr of exposure the snook may have a lower LC50; therefore, the snook 

may be more sensitive than the sheepshead minnow.

Acute Toxicity Endpoints for Estuarine and Marine Fish 

Species Endpoint MRID/Reference

Aldicarb

Sheepshead minnow 96-h LC50 = 41 ppb MRID 40228401 (U.S. EPA 

1986) 

Snook (Centropomus 

undecimalis)

36-h LC50 = 40 ppb Landau and Tucker 1984 

Sheepshead minnow 

(Cyprinodin variegates)

96-h LC50 = 170 ppb MRID 40228401 (U.S. EPA 

1986) 

Estuarine and Marine Fish, Chronic

Aldicarb

A chronic estuarine/marine fish early life-stage test using aldicarb (99% ai) has been conducted 

with the sheepshead minnow. The NOAEC was 50 ppb and the LOAEC was 88 ppb. The most 

sensitive endpoint was growth based on the mean standard length [MRID 00066341 (U.S. EPA 

1981b)]. The lowest chronic endpoint value available for sheepshead minnow is higher than the 

lowest acute endpoint value for sheepshead minnow. Therefore, it not appropriate to screen for 

chronic risks to estuarine/marine fish with this value. However, since there is an ACR of 114 

available for fish (freshwater fathead minnow ACR, see the Freshwater Fish, Chronic Aldicarb 

section above) this value was used to estimate a chronic NOAEC using the acute 96-h LC50 for 

sheepshead minnow from MRID 40228401. 

The estimated chronic NOAEC for the sheepshead minnow is 0.36 ppb and is calculated by 

dividing the 96-h LC50 of 41 ppb for the sheepshead minnow by the ACR for fathead minnow of 

114. As discussed in the Freshwater Fish, Chronic Aldicarb section above a 48-h LC50 value was 

used to calculate the ACR rather than a 96-h LC50 because none was available, this potentially 

over estimates the ACR for fathead minnow. Additionally, a robust estimate of an ACR (i.e., 
71 

geometric mean of ACRs for at least three fish species with at least one coldwater, one 

warmwater and one saltwater species) for aldicarb could not be calculated because only one fish 

species, the fathead minnow, had both acute and chronic acceptable endpoints available for 

determination of an ACR. While a more robust estimate of the ACR is desirable, the use of the 

fathead minnow ACR is a reasonable estimate but may be either a slight over or underestimate of 

ACR for fish. 

Chronic Toxicity Endpoints for Estuarine and Marine Fish

Species Endpoint (NOAEC) MRID/Reference 

Aldicarb

Sheepshead minnow Early life stage NOAEC = 50 

ppb 

MRID 00066341 (U.S. EPA 

1981b)

Sheepshead minnow Estimated NOAEC = 0.36 

ppb 

96-h LC50 for sheepshead 

minnow (41 ppb ai) divided 

by ACR (fathead minnow 48-

h EC50 of 8860 ppb ai divided 

by NOAEC of 78 ppb ai)

Estuarine and Marine Invertebrates, Acute

Aldicarb

Based on results from the preferred test species, pink shrimp and Eastern oyster, following test 

guidelines, the toxicity values fall in the range of 12 to 8800 ppb. Therefore, aldicarb is 

categorized as very highly to moderately toxic to estuarine/marine invertebrates on an acute 

basis. The 48-h EC50 for the Eastern oyster is reported as 8800 ppb. Therefore, the most 

sensitive estuarine/marine invertebrate tested was the pink shrimp, with a 96-h LC50 of 12 ppb 

[MRID 40228401 (U.S. EPA 1986)].

Acute Toxicity Endpoints for Estuarine and Marine Invertebrates 

Species Endpoint MRID/Reference 

Aldicarb

Eastern oyster 48-h EC50 = 8800 ppb MRID 40228401 (U.S. EPA 

1986) 

Pink shrimp 96-h LC50 = 12 ppb MRID 40228401 (U.S. EPA 

1986) 
72 

Estuarine and Marine Invertebrate, Chronic

Aldicarb

A chronic estuarine/marine invertebrate full life-cycle test using aldicarb (99% ai) has been 

conducted with the mysid shrimp. The NOAEC was 1 ppb and the LOAEC was 1.5 ppb. The 

most sensitive endpoint was average number of offspring [MRID 00066341(U.S. EPA 1981b)]. 

Chronic Toxicity Endpoints for Estuarine and Marine Invertebrates 

Species Endpoint MRID/Reference 

Aldicarb

Mysid shrimp Full life cycle NOAEC = 1 

ppb

MRID 00066341

Toxicity to Aquatic Plants

Aldicarb

According to CFR 40 Part 158.540, aquatic plant testing is generally not required for nonherbicides unless there is evidence of potential phytotoxicity at use rates from other lines of 

evidence. At this time, EFED has one study conducted on the marine diatom, Skeletonema 

costatum (MRID 40228401) and a study on Duckweed (MRID 47904402). The EC50 is >50 

ppm for the diatom and >88.7 ppm for duckweed. 

Toxicity Endpoints for Aquatic Plants

Species Endpoint MRID/Reference 

Aldicarb

Marine diatom, Skeletonema 

costatum

EC50 > 50 ppm MRID 40228401 

Duckweed, Lemna gibba EC50 >88.7 ppm MRID 47904402 

Summary of review of MRID 47904402 

In a 7 day acute toxicity study, Duckweed (Lemna gibba; freshwater floating aquatic vascular 

plants) were exposed to Aldicarb Technical at nominal concentrations of 0 (negative control), 

2.56, 6.40, 16.0, 40.0, and 100 mg ai/L under static renewal conditions. Measured 

concentrations were <0.20 (<LOQ, control), 2.17, 5.50, 14.3, 35.9, and 88.7 mg ai/L. 

The % growth inhibition of frond number in the treatment groups as compared to the control 

ranged from 4 to 41%. For biomass based on frond number, inhibitions ranged from 3 to 38%. 

For dry weight, inhibitions ranged from 5 to 46%. There were no compound related phytotoxic 

effects. The NOAEC for this study was 5.50 mg a.i./L, based on effects to frond number, 

biomass and dry weight at 14.3 mg a.i./L. For all endpoints that were included in this study (i.e.,

frond number, dry weight and growth rate), <50% effects were observed, resulting in an EC50 
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value >88.7 mg ai/L (i.e., the highest test concentration). Since a dose-response relationship was 

observed in this test and the highest test concentrations resulted in almost 50% effects, 

extrapolated EC50 values were calculated by the reviewer. The lowest extrapolated EC50 was 

110 (95% confidence interval: 90-130; slope = 1.74+/- 0.251) based on effects to dry weight. 

Although an EC50 value was not bound by the concentrations used in this test and the highest 

test concentration was not 100 mg a.i./L, the extrapolated EC50 value for dry weight and the 

available NOAECs are sufficient to establish endpoints from this study. This toxicity study is 

considered scientifically sound and classified acceptable. This study may be used to satisfy the 

guideline requirement for an aquatic plant toxicity study using Lemna sp.