Docket Number: EPA-HQ-OPP-2010-0243 

www.regulations.gov

United States Chemical Safety June 2010 

 Environmental Protection and Pollution Prevention 

 Agency (7510P) 

 

 Dichromic Acid Summary Document: 

Registration Review 

Docket Number: EPA-HQ-OPP-2010-0243 

www.regulations.gov

TABLE OF CONTENTS 

Dichromic Acid Registration Review Team ................................................................... 4 

I. PRELIMINARY WORK PLAN – DICHROMIC ACID.......................................... 5 

II. FACT SHEET ............................................................................................................ 14 

III. GLOSSARY of TERMS & ABBREVIATIONS ................................................... 17 

IV. APPENDIX A............................................................................................................ 19 

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Dichromic Acid Registration Review Team 

Human Health & Environmental Effects 

Nathan Mottl 

A. Najm Shamim 

 

Risk Management

Rebecca von dem Hagen 

Lance Wormell 

Office of General Counsel

Philip Ross 

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I. PRELIMINARY WORK PLAN – DICHROMIC ACID 

Introduction

The Food Quality Protection Act (FQPA) of 1996 mandated the registration 

review program. All pesticides distributed or sold in the United States generally must be 

registered by the U.S. Environmental Protection Agency (USEPA, EPA, or the Agency), 

based on scientific data showing that they will not cause unreasonable risks to human 

health or the environment when used as directed on product labeling. The registration 

review program is intended to make sure 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 or the environment. Changes 

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

registration review program, the Agency periodically reevaluates pesticides to make sure 

that as change occurs, products in the marketplace can be used safely. Information on 

this program is provided at http://www.epa.gov/oppsrrd1/registration_review/. 

The Agency is implementing the registration review program pursuant to Section 

3(g) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and will review 

each registered pesticide every 15 years to determine whether it continues to meet the 

FIFRA standard for registration. The Agency will consider benefits information and data 

as required by FIFRA. The public phase of registration review begins when the initial 

docket is opened for each case. The docket is the Agency’s opportunity to state what it 

knows about the pesticide and what additional risk analyses and data or information it 

believes are needed to make a registration review decision. After reviewing and 

responding to comments and data received in the docket during this initial comment 

period, the Agency will develop and commit to a final work plan and schedule for the 

registration review of the active ingredient dichromic acid. 

The sole pesticidal use of dichromic acid (PC Code 068306) is for the formulation 

of tank mix solutions for chromated copper arsenate (CCA). CCA is sold as a restricted 

use wood preservative primarily for commercial and institutional uses in indoor and 

outdoor sites. Effective December 31, 2003, CCA registrants terminated through 

voluntary amendments to product registrations virtually all residential uses. The only 

remaining residential uses are shakes/shingles and permanent wood foundations. There 

are currently no food uses, tolerances or exemptions from the requirement of a tolerance 

for dichromic acid. 

A pesticide product containing dichromic acid was first registered in 1994. 

Because dichromic acid was registered after November 1984, this ingredient was not 

considered under EPA’s reregistration program. However, a Reregistration Eligibility 

Decision (RED) for chromated arsenicals was completed in 2008. The 2008 RED 

addressed potential exposure and risk from chromium (VI) oxide (also known as 

“chromic acid”). Chromic acid and dichromic acid are both created through the same 

chemical processes and composed of chromium in the hexavalent form (CR(VI)), with 

dichromic acid being a relatively unstable form of chromic acid. Because chromic acid 

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and dichromic acid are composed of the same chemical of toxicological significance 

(hexavalent chromium), the Agency intends to incorporate data received in response to 

the chromic acid RED DCI into the risk assessments to be performed for the registration 

review of dichromic acid. The Agency anticipates issuing the chromic acid RED DCI in 

FY2011 and anticipates reviewing any data received in response to the RED DCI prior to 

conducting the registration review risk assessments for dichromic acid. Also, the Agency 

notes that this registration review will be based on updated labels received in response to 

the 2008 chromated arsenicals RED and approved by the Agency in May 2010 for the 

two active registrations. The updated labels reflect mitigation measures outlined in the 

2008 RED. 

Risk Assessment Status & Anticipated Data Needs

Human Health Risk Assessment Status and Anticipated Data Needs 

The Agency reviewed the hazard and exposure databases for dichromic acid. As 

a result of this review, EPA confirmed that the data to be required for dichromic acid as a 

result of the September 2008 chromated arsenicals RED are still needed. The studies that 

will be required upon issuance of the RED Data Call-In (DCI) can be found in the 

Agency’s chromated arsenicals RED at http://www.regulations.gov in docket number 

EPA-HQ-OPP-2003-0250. The Agency does not anticipate the need to require any other 

human health data for dichromic acid through the registration review program. 

Dietary Assessment

 Acute and chronic dietary assessments are not necessary for dichromic acid 

because there are no uses of dichromic acid attributable to the dietary route of exposure.

 Because wood preservative use is not expected to result in drinking water 

exposure, a drinking water assessment is not anticipated to be needed. According to the 

RED, “studies of sorption into soils from utility poles, have shown that the release of 

metals into soils/sediments from the base of treated wood, decks or utility poles or from 

the pressure treatment facilities, do not show a high degree of migration, either to 

groundwater or to the surface. In most cases, after migration of the metals a few meters 

down into soil, these metals attain the background level concentration of soil.”

Tolerances

There are currently no tolerances or exemptions for the requirement of a tolerance 

for dichromic acid. 

Occupational and Residential Assessment and Risk

The Agency reviewed all available data associated with dichromic acid and has 

determined that the currently registered uses of dichromic acid may result in occupational 

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exposure. An occupational risk assessment for inhalation exposure to Cr (VI) was 

performed in 2008 for the chromated arsenicals RED. The Agency reviewed the 2008 

risk assessment and determined that the data to be called in upon the issuance of the 

chromated arsenicals RED DCI are still needed and does not anticipate the need to 

require any other human health data for dichromic acid through the registration review 

program. Contingent upon the receipt of the data for chromic acid to be required through 

the reregistration process from chromated arsenicals, the Agency may develop new 

occupational inhalation risk assessments for the dichromic acid registration review. 

CCA is no longer registered for use on wood intended to be used for decks or play 

sets and the remaining two residential uses (shakes/shingles and permanent wood 

foundations) are not expected to result in significant exposure to dichromic acid. 

Therefore, a residential assessment is not required for these uses. 

Aggregate Exposure and Risk

In examining aggregate exposure, EPA takes into account the available and 

reliable information concerning exposures to pesticide residues in food and drinking 

water, and non-occupational pesticide exposures. As previously stated, acute and chronic 

dietary assessments will not be conducted for dichromic acid because there are no uses of 

dichromic acid which would be attributable to the dietary route of exposure. The 

remaining residential uses of dichromic acid are not expected to result in significant 

residential exposure. Therefore, no need is anticipated for an aggregate exposure 

assessment. 

Anticipated Human Health Data Needs

EPA confirmed that the data to be required for dichromic acid as a result of the 

September 2008 chromated arsenicals RED are still needed and the Agency does not 

anticipate the need to require any other human health data for dichromic acid through the 

registration review program. 

For further information see the document titled, “Summary of Human Health 

Effects Data for the Dichromic Acid Registration Review Decision Document,” dated 

May 27, 2010. 

Anticipated Physical/Chemical Property Data Needs 

All product chemistry data requirements have been fulfilled for dichromic acid. 

Therefore, it is anticipated that additional product chemistry data will not be needed for 

dichromic acid. 

For further information see the document titled, Dichromic Acid: Product 

Chemistry/Environmental Fate and Eco-Effects Scoping Document dated May 6, 2010. 

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Environmental Fate and Ecological Risk Assessment Status and Anticipated Data 

Needs

The Agency reviewed the environmental fate and ecological hazard databases for 

dichromic acid. As a result of this review, EPA confirmed that the data to be required for 

dichromic acid as a result of the chromated arsenicals RED are still needed. The studies 

that will be called in for reregistration can be found in the Agency’s chromated arsenicals 

RED at http://www.regulations.gov in docket number EPA-HQ-OPP-2003-0250. The 

Agency does not anticipate the need to require any additional environmental fate data for 

dichromic acid through the registration review program. 

For further information see the document titled, “Dichromic Acid: Product 

Chemistry/Environmental Fate and Eco-Effects Scoping Document” dated May 6, 2010. 

Endangered Species 

 The Agency has not conducted a risk assessment that supports a complete 

endangered species determination for dichromic acid. The ecological risk assessment 

planned during registration review will allow the Agency to determine whether 

chromium (VI), the chemical of toxicological concern found in pesticide products 

containing dichromic acid (Case 5012) and chromic acid (Case 0132), has “no effect” or 

“may affect” federally listed threatened or endangered species (listed species) or their 

designated critical habitats. Because the chemical of toxicological concern and use 

patterns are the same for chromic acid and dichromic acid, the Agency intends to perform 

a comprehensive endangered species assessment for chromium (VI). When an assessment 

concludes that a pesticide’s use “may affect” a listed species or its designated critical 

habitat, the Agency will consult with the U.S. Fish and Wildlife Service and/or National 

Marine Fisheries Services (the Services), as appropriate. 

Incidents:

In the chromated arsenicals RED only limited incident reports are associated with 

exposure to end-use products containing chromated arsenicals. In contrast, a large body 

of literature exists on the health effects (acute and chronic) in humans of exposure to the 

components of chromated arsenicals, particularly arsenic and, to a lesser degree, 

chromium and copper. Itching, burning rashes, neurological symptoms, and breathing 

problems associated with handling unmarked CCA-treated wood have been reported. Sap 

draining from CCA treated wood stairs has been reported as a potential source of dermal 

and inhalation exposure leading to dermatitis and development of film on the teeth. At 

least one individual reported “ruined” nerves in feet and legs which he attributed to 

exposure to saw dust and fumes from cutting and routing CCA-treated lumber. No new 

incidents have been reported for dichromic acid since the chromated arsenicals RED has 

been completed. 

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Timeline:

EPA has created the following estimated timeline for the completion of the 

dichromic acid registration review: 

Anticipated Schedule

Activities Estimated Month/Year

Phase 1: Opening the docket 

Open Public Comment Period for Dichromic Acid Docket June 2010 

Close Public Comment Period August 2010 

Phase 2: Case Development 

Develop Final Work Plan (FWP) December 2010 

Issue DCI December 2011 

Data Submission December 2015 

Open Public Comment Period for Preliminary Risk Assessments June 2016 

Close Public Comment Period September 2016 

Phase 3: Registration Review Decision 

Open Public Comment Period for Proposed Reg. Review Decision December 2016 

Close Public Comment Period March 2017 

Final Decision and Begin Post-Decision Follow-up 2017 

Total (years) 7 

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Guidance for Respondents:

The public is invited to comment on EPA’s preliminary registration review work 

plan and rationale. The Agency will carefully consider all comments as well as any 

additional information or data provided in a timely manner prior to issuing a final work 

plan for the dichromic acid registration review case. 

Trade Irritants 

Through the registration review process, the Agency intends to solicit information 

on trade irritants and, to the extent feasible, take steps toward facilitating irritant 

resolution. Growers and other stakeholders are asked to comment on any trade irritant 

issues resulting from lack of Maximum Residue Limits (MRLs) or disparities between 

U.S. tolerances and MRLs in key export markets, providing as much specificity as 

possible regarding the nature of the concern. 

Water Quality 

Dichromic acid is not identified as a cause of impairment for any water bodies 

listed as impaired under section 303(d) of the Clean Water Act, based on information 

provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_grou

p_id=885. In addition, no Total Maximum Daily Loads (TMDL) have been developed 

for dichromic acid, based on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_gr

oup_id=885&p_pollutant_group_name=PESTICIDES. More information on impaired 

water bodies and TMDLs can be found at http://www.epa.gov/owow/tmdl/. The Agency 

invites submission of water quality data for this pesticide. To the extent possible, data 

should conform to the quality standards in Appendix A of the OPP Standard Operating 

Procedure: Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s 

Registration Review Risk Assessment and Management Process (see: 

http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm) in order to 

ensure they can be used quantitatively or qualitatively in pesticide risk assessments. 

Environmental Justice 

EPA seeks to achieve environmental justice, the fair treatment and meaningful 

involvement of all people, regardless of race, color, national origin, or income, in the 

development, implementation, and enforcement of environmental laws, regulations, and 

policies. To help address potential environmental justice issues, the Agency seeks 

information on any groups or segments of the population who, as a result of their 

location, cultural practices, or other factors, may have atypical, unusually high exposure 

to dichromic acid compared to the general population. Please comment if you are aware 

of any sub-populations that may have atypical, unusually high exposure compared to the 

general population. 

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Structure Activity Relationships 

EPA must rely upon information of appropriate quality and reliability for each 

decision made by the Agency. In the Office of Pesticide Programs (OPP), the evaluation 

process for a pesticide chemical traditionally begins with the applicant’s submission of a 

set of studies conducted with the specific pesticide chemical of interest. The use of the 

results of such testing (measured data) is a logical, scientifically rigorous process that 

identifies the physical, chemical, and environmental fate properties of the pesticide, as 

well as the dose and endpoints at which an adverse effect can occur in various animal 

species. 

Today, there is significant interest in alternative techniques, i.e., techniques other 

than data generation that could significantly inform the Agency’s decision-making 

process. Recently, OPP has made increasing use of structure activity relationship (SAR) 

as part of its regulatory decision-making process. In the SAR process, a chemical's 

molecular structure is compared to that of other chemicals for which data are available. 

These structural similarities are then used to make predictive judgments about a 

chemical’s physical, chemical, and biological properties. Thus, the chemical’s physical, 

chemical, and biological properties are a function of (or directly related to) the chemical’s 

molecular structure. Quantitative SAR is referred to as QSAR. To develop a QSAR, a 

selected set of measured data on a single physical, chemical, or biological property is 

used to derive a model (an equation) to predict the value of that property. 

 Since SAR assessments and QSAR modeling are another set of tools that are 

available to Agency scientists, OPP has begun a process shift that envisions shifting from 

the current study-by-study approach to an approach in which the use of predicted data, 

generated using validated models, is considered along with information from open 

literature and studies specifically generated under Part 161 requirements. All relevant 

information would be considered as part of a weight-of-the-evidence evaluation. 

At this time, EPA believes that for certain endpoints, especially physical/chemical 

and fate properties, that SAR and QSAR might be effectively utilized to fulfill these data 

requirements for many antimicrobial pesticide chemicals. When considering biological 

properties, at this time, EPA believes that SAR and QSAR can be most effectively 

utilized in the evaluation of chemicals that exhibit lower toxicity for human health and/or 

ecotoxicity parameters. This is appropriate because the risk assessment for lower toxicity 

chemicals can be stream-lined, i.e., a screening-level assessment procedure rather than 

multiple tiers of assessments with progressively more data requirements. 

If stakeholders believe that submission of predicted data can fulfill one of the data 

needs for dichromic acid, then the Agency invites submission of this information. The 

submitter would be expected to supply a rationale describing the utility of the information 

and provide documentation on the scientific validity of the information. The 

determination that the predicted data fulfills the data requirement would be at the sole 

discretion of the Agency. Pre-submission consultation with the Agency is encouraged. 

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Endocrine Disruptor Screening Program 

As required under FFDCA section 408(p), EPA has developed the Endocrine 

Disruptor Screening Program (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. 

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. This list of chemicals was selected based on the potential for human 

exposure through pathways such as food and water, residential activity, and certain postapplication agricultural scenarios. This list should not be construed as a list of known or 

likely endocrine disruptors. 

Dichromic acid is not among the group of 58 pesticide active ingredients on the 

initial list to be screened under the EDSP. Under FFDCA sec. 408(p) the Agency must 

screen all pesticide chemicals. Accordingly, EPA anticipates issuing future EDSP test 

orders/data call-ins for all pesticide active ingredients. 

For further information on the status of the EDSP, the policies and procedures, the 

list of 67 chemicals, the test guidelines and the Tier 1 screening battery, please visit our 

website: http://www.epa.gov/endo/. 

Additional Information 

Stakeholders are also specifically asked to provide available information and data 

that will assist the Agency in refining the risk assessments. The Agency is interested in 

receiving the following information: 

1. Confirmation on the following label information: 

a. Sites of application 

b. Formulations 

c. Application methods and equipment 

d. Maximum application rates 

e. Frequency of application, application intervals and maximum 

number of applications 

f. Geographic limitations on use 

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2. Use or potential use distribution 

3. Use history 

4. Usage/use information for non-agricultural uses (e.g., materials 

preservation) 

5. Typical application interval 

6. State or local use restrictions 

7. Ecological incidents (non-target plant damage and avian, fish, 

reptilian, amphibian and mammalian mortalities) not already reported 

to the Agency 

8. Monitoring data 

9. Structure Activity Relationships 

Next Steps: 

After the 60-day comment period closes, the Agency will review and respond to 

any comments received in a timely manner, and then issue a Final Work Plan for 

dichromic acid. 

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II. FACT SHEET 

Background Information

 Chemical Name: Dichromic Acid 

 Common Names: Dichromic Acid, Disodium Salt, Dihydrate; Sodium 

Bichromate 

 Registration review case number: 5012 

 PC Code: 068306 

 CAS#: 7789-12-0 

 Technical Registrant: Elementis Chromium, LP 

 First approved for use in a registered product: 1994 

 Two active registrations: one manufacturing use product and one end use product. 

 Antimicrobials Division Chemical Review Manager (CRM): Rebecca von dem 

Hagen, Vondem-Hagen.Rebecca@epa.gov 

 Antimicrobials Division Product Manager (PM): Jacqueline CampbellMcFarlane, campbell-mcfarlane.jacqueline@epa.gov 

Chemical Structure:

Use & Usage Information

 Type of Pesticide: Fungicide, Insecticide, Miticide and Molluscicide 

 Antimicrobial Use Sites:

o Formulation intermediate in the production of CCA wood preservatives. 

Use sites of CCA-treated wood include: 

 Commercial and institutional uses in indoor and outdoor sites 

 Limited residential uses including shakes/shingles and permanent 

wood foundations 

Recent Regulatory Actions

Updated labels received in response to the 2008 chromated arsenicals RED were 

approved by the Agency in May 2010. The updated labels reflect the mitigation 

measures outlined in the 2008 RED. The chromated arsenicals RED can be viewed at 

http://www.regulations.gov in docket number EPA-HQ-OPP-2003-0250 

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Human Health Risk Assessment Status

EPA confirmed that the data that will be required for dichromic acid upon the 

issuance of the chromated arsenicals RED DCI are still needed and the Agency does not 

anticipate needing to require any other human health data for dichromic acid through the 

registration review program. 

For further information see the document titled, “Summary of Human Health 

Effects Data for the Dichromic Acid Registration Review Decision Document,” dated 

May 27, 2010.

Environmental Fate & Ecological Risk Assessment Status

The Agency reviewed the environmental fate and ecological hazard databases for 

dichromic acid. As a result of this review, EPA confirmed that the data to be required for 

dichromic acid upon the issuance of the chromated arsenicals RED DCI are still needed 

and the Agency does not anticipate the need to require any other environmental fate and 

ecological risk studies for dichromic acid through the registration review program. 

For further information see the document titled, “Dichromic Acid: Product 

Chemistry/Environmental Fate and Eco-Effects Scoping Document” dated May 6, 2010.

Tolerances 

There are currently no tolerances or exemptions for the requirement of a tolerance 

for dichromic acid. 

Data Call-In Status

 

In addition to the data call-in (DCI) scheduled to be issued through the chromated 

arsenicals RED in FY 2011, the Agency anticipates the need to require additional data to 

complete a risk assessment during the registration review of this case. 

Labels 

There are 2 registered products that contain dichromic acid. The EPA 

Registration Numbers are provided in Tables 1 below. For future reference, during 

registration review a list of product registration numbers will be included in the docket. 

Product registration labels may be obtained from the Pesticide Product Label System 

(PPLS) website at: http://oaspub.epa.gov/pestlabl/ppls.home. 

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Table 1. Registered Active Antimicrobial Products of Dichromic Acid 

Registration # Registration Name Company Name Formulation Type % of Active 

Ingredient 

75449-1 Sodium Bichromate 

Liquid

Elementis 

Chromium

Formulation 

Intermediate 69.0%

75449-3 Sodium Bichromate 

Solution

Elementis 

Chromium

Soluble 

Concentrate 69.0%

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III. GLOSSARY of TERMS & ABBREVIATIONS

ai Active Ingredient 

AR Anticipated Residue 

ASTM American Society for Testing and Materials 

AWPA American Wood Preserver’s Association 

CFR Code of Federal Regulations 

cPAD Chronic Population Adjusted Dose 

CSF Confidential Statement of Formula 

CSFII USDA Continuing Surveys for Food Intake by Individuals 

DCI Data Call-In 

DEEM Dietary Exposure Evaluation Model 

DFR Dislodgeable Foliar Residue 

DNT Developmental Neurotoxicity 

DWLOC Drinking Water Level of Comparison 

EC Emulsifiable Concentrate Formulation 

EDWC Estimated Drinking Water Concentration 

EEC Estimated Environmental Concentration 

EPA Environmental Protection Agency 

EUP End-Use Product 

FDA Food and Drug Administration 

FIFRA Federal Insecticide, Fungicide, and Rodenticide Act 

FFDCA Federal Food, Drug, and Cosmetic Act 

FQPA Food Quality Protection Act 

FOB Functional Observation Battery 

GENEEC Tier I Surface Water Computer Model 

IR Index Reservoir 

LC50 Median Lethal Concentration. A statistically derived concentration of a 

substance that can be expected to cause death in 50% of test animals. It is 

usually expressed as the weight of substance per weight or volume of water, air 

or feed, e.g., mg/l, mg/kg or ppm. 

LD50 Median Lethal Dose. A statistically derived single dose that can be expected to 

cause death in 50% of the test animals when administered by the route indicated 

(oral, dermal, inhalation). It is expressed as a weight of substance per unit 

weight of animal, e.g., mg/kg. 

LOC Level of Concern 

LOAEL Lowest Observed Adverse Effect Level 

μg/g Micrograms Per Gram 

μg/L Micrograms Per Liter 

mg/kg/day Milligram Per Kilogram Per Day 

mg/L Milligrams Per Liter 

MOE Margin of Exposure 

MRID Master Record Identification (number). EPA's system of recording and tracking 

submitted studies. 

MUP Manufacturing-Use Product 

NA Not Applicable 

NAWQA USGS National Ambient Water Quality Assessment 

NPDES National Pollutant Discharge Elimination System 

NR Not Required 

NOAEL No Observed Adverse Effect Level 

OPP EPA Office of Pesticide Programs 

OPPTS EPA Office of Prevention, Pesticides and Toxic Substances 

PAD Population Adjusted Dose 

PAIRA Pure Active Ingredient Radiolabelled 

PCA Percent Crop Area 

PDP USDA Pesticide Data Program 

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PHED Pesticide Handler's Exposure Data 

PHI Preharvest Interval 

ppb Parts Per Billion 

PPE Personal Protective Equipment 

ppm Parts Per Million 

PRZM/EXAMS Tier II Surface Water Computer Model 

Q1* The Carcinogenic Potential of a Compound, Quantified by the EPA's Cancer 

Risk Model 

RAC Raw Agriculture Commodity 

RED Reregistration Eligibility Decision 

REI Restricted Entry Interval 

RfD Reference Dose 

RQ Risk Quotient 

SCI-GROW Tier I Ground Water Computer Model 

SAP Science Advisory Panel 

SF Safety Factor 

SLN Special Local Need (Registrations Under Section 24©) of FIFRA) 

TGAI Technical Grade Active Ingredient 

TEP Typical End-Use Product 

USDA United States Department of Agriculture 

UF Uncertainty Factor 

WPS Worker Protection Standard 
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IV. APPENDIX A

Use Patterns for DICHROMIC ACID 

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Wood Preservatives Production of wood preservative pesticide formulations

Formulation Intermediate 75449-1 

Pour Product is for manufacturing use 

only for the production of pesticide formulations for use as wood preservatives to control fungi, insects and mites. 

Wood preservative 

Lumber, timber, post, poles and piles 

Soluble Concentrate 75449-3 

Pour CCA Type C Instructions: 

For a 1.5% working solution to one thousand gallons of water, add 32 gallons of 25% copper sulfate solution. Add 10 gallons of Sodium Dichromate Solution 69%. The final component to be added is 4.9 gallons of arsenic acid 75%. CCA Type A Instructions: For a 1.5% working solution 10 one thousand gallons of water, add 30 gallons of 25% copper sulfate solution. Add 13 gallons of Sodium Dichromate Solution 69%. The final component to be added is 2.6 gallons of arsenic acid 75%. 

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