# TSCA New Chemicals Program (NCP) Categories in Support of SNURs for 17 Chemical Substances

EPA Docket: EPA-HQ-OPPT-2008-0920

May 14, 2010http://www.epa.gov/oppt/newchems/chemcat.htm



# TSCA NEW CHEMICALS PROGRAM (NCP) CHEMICAL CATEGORIES

Contact: Office of Pollution Prevention and Toxics

U.S. Environmental Protection Agency 1200 Pennslyvania Avenue, N.W Wa shington, D.C. 20460 Telephone: (202) 564-8996 Miriam Wi ggins-Lewis (mail code 7405M; wigginslewis.m i riam@epa.gov) J. Vincent Nabholz (mail code 7403M; nabholz.joe@epa.gov)

Rebecca Jones (mail code 7403M; jones.rebecca@epa.gov) Last revised: October, 2002Note on Test Guidelines Cited in this Document: This document contains references to test guidelines that originally appeared in title 40, chapter I, subchapter R of the Code of Federal Regul ations (CFR). Since that tim e, the "OPPTS Harmonized Test Guidelines" have been developed by EPA's Office of Prevention, Pesticides and Toxic Substances for use in the testing of pesticides and toxic substances, and the development of test data that m u st be submitted to the Agency for review under Federal regulations. These guidelines can be found at http://www.epa.gov/docs/OPPTS_Harmonized/. Until we fully update all the references contained within this categories document, you can find any new OPPTS guideline that corresponds to an old CFR citation. For example, the fish acute toxicity test at 40 CFR 797.1400 has been replaced by OPPTS 850.1075, and Ready Biodegradability at 40 CFR 796.3180, etc. has been replaced by OPPTS 835.3110.
Disclaimer: EPA's Office of Pollution Prevention and Toxics (OPPT) groups chem icals with shared chem ical and toxicological properties into categories so that PMN reviews are facilitated. PMN submitters and EPA reviewers benefit from the accum u lated data and past decisions represented by a category. EPA considers all PMNs, including new chemical substances which fall within such categories, on a case-by-case basis and uses the m o st appropriate structural analogue to support any concerns for health or environmental effects. For any new chemical substance, if EPA determines, under TSCA section 5(e), that the substance "may present an unreasonable risk of injury to health or the environment,” the PMN substance can be subjected to appropriate control actions and/or testing under TSCA section 5(e). This “may present” finding is developed through the application of category-based or chemical-by-chemical assessment of hazard endpoints and case-specific exposure assessment. The categories included in this com p ilation represent chem icals for which sufficient assessm ent experience has been accum u lated so that hazard concerns and testing recomme ndations vary little from chemical to chemical within the category. Thus, these categories do not necessarily represent the chemicals of greatest concern to the Agency. By the sam e token, the categories are also not intended to be a com p rehensive list of all substances that m a y be subject to further action in the New Chemicals Program

. If a new chemical substance is structurally similar to a substance f o r which EPA has positive toxicity data and there is sufficient exposure, EPA m a y regulate that substance under section 5(e) of the Toxic Substances Control Act (TSCA) based on its potential unreasonable risk. The hazard potential of a PMN substance is dependent on the m o lecular weight of the compound, the presence/absence of activating/deactivating substituents, other physical/chem i cal properties, and the likely route of exposure. Typically, concerns are confined to chemicals with m o lecular weights <1,000 whenever inhalation exposure to humans or environmental release is expected, and to species <500 when dermal exposure to humans is expected. Additional information on testing conditions and testing options for specific PMN chemical substances that appear to fall within one of these categories is available by contacting the New Chemicals Branch at 202-260-3725 or the TSCA Hotline at 202-554-1404. This is to serve only

iias a guide f o r PMN submitters. PMN submitters are urged to have protocols and testing schem es evaluated by the New Chemicals Program prior to comme ncing testing on a PMN substance. However, under no circumstance does such an evaluation mean that the new chemical substance is not subject to further review during any TSCA section 5 review period for the PMN substance or that additional testing or regulatory action ma y not be recomme nded. Finally, even if EPA does not m a ke the potential unreasonable risk finding for a new chemical substance, the Agency ma y still recomme nd the use of engineering controls or personal protective equipment to reduce exposures in the workplace if the PMN substance is a potential irritant or sensitizer.

iiiTable of Contents

Acid Chlorides ................................................................1 Acid Dyes and Am photeric Dyes .................................................2
Ac rylamides ..................................................................5
A crylates/Methacrylates ........................................................8 Aldehydes ..................................................................1 0 Al iphatic Amines .............................................................1 4 Alkoxysilanes ................................................................1 6 Aluminum Compounds ........................................................1 8 Aminobenzothiazole Azo Dyes ..................................................2 3 Anhydrides, Carboxylic Acid ...................................................2 5 Anilines ....................................................................2 6 Dianilines .............................................................3 0
A nionic Surfactants ...........................................................3 4
A zides .....................................................................3 6
B enzotriazoles ...............................................................3 9
B enzotriazole-hindered phenols .................................................4 2
Boron Com pounds ............................................................4 5
Ca tionic Dyes ................................................................5 0
C ationic (quaternary ammonium) surfactants .......................................5 1
C obalt ......................................................................5 2
D iazoniums .................................................................5 6
D ichlorobenzidine-based Pigments ...............................................6 0

ivDithiocarbamates .............................................................6 2 Epoxides ....................................................................6 4
Es ters ......................................................................6 5
Et hylene Glycol Ethers ........................................................6 8 Hydrazines and Related Com pounds ..............................................7 0 Hi ndered Amines .............................................................7 3
I mides ......................................................................7 4
D iisocyanates ................................................................7 7 

### $ -Naphthylamines, Sulfonated ..................................................8 0 Lanthanides or Rare Earth Metals ................................................8 2
N eutral Organics .............................................................8 6 Nickel Com pounds ............................................................8 8 Noni onic Surfactants ..........................................................9 0
O rganotins ..................................................................9 2
P eroxides ...................................................................9 6 Persistent, Bioaccum u lative,

a nd Toxic (PBT) Chemical s...................................9 8 Phenolphthaleins ............................................................1 01
P henols ....................................................................1 03
P hosphates, Inorganic ........................................................1 06
P hosphinate Esters ...........................................................1 09 Polyanionic Polym e rs (& Monom ers) ............................................1 12
P olycationic Polymers ........................................................1 13
P olynitroaromatics ...........................................................1 14

vRespirable, Poorly Soluble Particulates ...........................................1 18 Rosin .....................................................................1 23 Stilbene, derivatives of 4,4-bis(triazin-2-ylam ino)- .................................1 25
T hiols .....................................................................1 28 Substituted Triazines .........................................................1 31 Triarylm ethane Pigments/Dyes with Non-solubilizing Groups ...............................1 32
V inyl Esters ................................................................1 37
V inyl Sulfones ..............................................................1 39
S oluble complexes of Zinc .....................................................1 43 Zirconium Compounds .......................................................1 44

viCategory: Acid Chlorides Environmental Toxicity
Definition

. This category includes carbonyl chlorides (R-C[=O]Cl) and sulfochlorides (RS[=O] C l) where R m a y be either aliphatic or aromatic. Toxicity is limited by the fact that this class of compounds hydrolyzes and also, probabl y, if the octanol/water partition coefficient (Kow) is above a log Kow value of 8. It has been assum e d that these compounds need to be absorbed to be toxic, therefore, compounds with MWs > 1000 will probably be excluded in the future once this assum p tion is confirm e d with toxicity information. However, toxicity information is needed to confirm this assum p tion.
Haz a rd Concerns

. Acute toxicity for three m e mb ers of this category are available and all have been shown to be moderately toxic to aquatic organisms (i.e., acute toxicity values between 1 and 100 m g /L): benzoyl chloride, fish 96-h LC50 = 35.0 m g /L, an aromatic dicarboxyl dichloride, fish 96-h LC50 = 6.2 m g /L, and benzene sulfochloride, fish 48-h LC50 = 3.0 m g /L. All of these tests have been done with the static m e thod using nominal concentrations. It is unclear just how acid chlorides are toxic to aquatic organisms. It is known that acid chlorides hydrolyze to the carboxylic/sulfonic acid and HCl. It is not known if the toxic effect is the result of (1) absorption of the acid chloride and hydr olysis within the m emb rane, or (2) the HCl produced from the hydrolysis. It is known th at the carboxylic/sulfonic-acid hydrolysis products are of low toxicity.
Boundaries

. There are no known lower boundaries. The upper boundaries will be based on K ow and MW when enough information is obtained. In general, when the log K ow value is < 8, the environmental base set of tests will be requested f o r aquatic releases and the terrestrial base set of tests will be recomme nded for terrestrial exposures. Wh en the log K ow is > 8, testing will be requested until enough information is obtained to determine whether these compounds will have no toxic effects at saturation. Generally, m emb ers of this category will have MWs of less than 1000 but testing of m emb ers with a MW > 1000 m a y be requested to confirm whether acid chlorides have to be absorbed to be toxic. General Testing Strategy. The testing strategy f o r acid chlorides will consist of two steps. (1) Hydrolysis as a function of pH at 25 °C (40 CFR 796.3500) will be recomme nded. Depending on the outcom e of this environmental fate testing and reassessment, (2) the aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures with the fish acute toxicity test done once or twice. Chronic toxicity testing for aquatic organisms include: the fish early life state toxicity test, the daphnid partial life cycle toxicity test and the algal toxicity test. The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm acute toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity te sting for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay. October, 1990

1Category: Acid Dyes and Amphoteric Dyes Environmental Toxicity
Definition. Organic dyes are divided into four classes depending on the type of electronic charge of the dye: nonionic (neutral dyes); anionic (negative charge or acid dyes); cationic (positive charge) dyes; and amphoteric (mixture of positive and negative charges on sam e mo lecule) dyes. Nonionic or neutral dyes are assessed as neutral organic chem icals for which there is a separate category description, and cationic dyes also have a separate category description. Amphoteric dyes are assessed either as cationic or anionic dyes depending on dominant net charge.
Haz a rd Concerns. Analysis of over 200 acid dyes (Auer et al. 1990, Nabholz 1990, Sigman et al. 1983, Tonogai et al. 1979, Little and Lam b 1972, ADMI 1974) have indicated that som e m onoacid and diacid dyes can show moderate to high toxicity (i.e., acute values < 100 m g /L and < 1 m g /L) to fish and aquatic organisms. Dyes with three or m o re acid groups showed low toxicity (i.e., acute values > 100 m g /L) towards fish and invertebrates. Som e me tal chelated dyes, i.e., Al, Co, Cr, Fe, have shown moderate toxicity towards fish and daphnids and the toxicity has not been explained by the residual free (un-chelated) m e tal ion in the dye product. All acid dyes showed moderate toxicity towards green algae. Analysis of available data (Auer et al. 1990, Nabholz 1990) has suggested that effects to algae were not the result of direct toxicity but represented an indirect effect due to shading. Senior regulatory decision-m a kers in OPPT (then OTS) decided in 1988 that the risk to alg ae from indirect (shading) toxicity was not an unreasonable risk for two m a in reasons: (1) algae grew quickly as soon as the dye was diluted, and (2) the release of colored effluents in the U. S. generally results in imme diate com p laints by citizens to their local authorities, e.g., county and state governm e nts. The rapid response by the public generally results in quick regulatory action by local officials. Since there is no SAR for acid dyes (Auer et al. 1990), hazard profiles for m onoacid dyes are developed using measured data or data for the nearest analog(s).
Boundaries. Acids dyes m u st have som e water solubility and m o lecular weights generally need to be near or below 1000. General Testing Strategy.
I. Release to Aquatic Ecosystem s : Tier 1. Because of the above boundary conditions, and the need to assess human exposure as well as environmental toxicity, if there is insufficient knowledge about the water solubility of the dye, then it should be measured (40 CFR §796.1860). The fish and daphnid acute toxicity tests f r om the aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures. The acute toxicity tests for fish (40 CFR §797.1400) and daphnids (40 CFR §797.1300) will be done using the flow-through m e thod with measured concentrations, and effective concentrations will be based on 100% active ingredients (AI) and m ean measured concentrations. If there is no significant risk from the PMN after the results of the fish and daphnid acute

2toxicity tests have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Direct and Indirect Photolysis Screening Test (40 CFR 796.3765). If t1⁄2 < 2 days, go to Tier 3; if t1⁄2 > 2 days, go to Tier 4. Tier 3a. If t1⁄2 < 2 days and photolysis products are known and/or identified, then assess photolysis products for environmental hazards. Tier 3b. If t1⁄2 < 2 days and photolysis products are not known and/or identifiable, then prepare a stock solution of PMN using the sta ndard humic-containing solution described in the direct and indirect photolysis screening test [40 CFR 796.3765 (b)(2) and (c)(2)], expose to sunlight for at least 6 half-lives (t1⁄2), and test photolysis products for toxicity with m o st sensitive species from environmental base set. Tier 4. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR 797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; and statistical analysis of effective concentrations at days 7, 14, 21, and 28. Daphnid chronic toxicity testing ( 40 CFR 797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21. Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation Modified Sturm Test Closed Bottle Test Modified OECD Screening Test Modified MITI Test (I) Modified AFNOR Test
II. Release to Terrestrial Ecosystem s : 40 CFR 796.3100 40 CFR 796.3260 40 CFR 796.3200 40 CFR 796.3240 40 CFR 796.3220 40 CFR 796.3180

The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded f or terrestrial exposures. Chronic toxicity testing fo r terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay.

3References . American Dye Manufacturers Institute, Inc. (ADMI), 1974, "Dyes and the Environment: Reports on Selected Dyes and Their Effects," Vol. II, ADMI, New York. Auer, C.M., Nabholz, J.V. and Baetcke, K.P., 1990, "Mode of Action and the Assessment of Chemical Hazards in the Presence of Limited Data: Use of Structure-Activity Relationships (SAR) under TSCA, Section 5," Environmental Health Perspectives , Vol. 87, pp. 183-197. Little, L.W

. and Lam b J.C., III, 1972, "Acute Toxicity of 46 Selected Dyes to the Fathead Minnow, Pim e phales promelas ,"Final Report to the American Dye Manufacturers Institute,Inc., UNC W a stewater Research Ce nter, Departm e nt of Environmental Sciences and Engineering, School of Public Health, Un iversity of North Carolina, Chapel Hill, NC. Nabholz, J.V., 1990, "The OTS PMN ECOTOX Data Base: a Confidential Business Information (CBI) Collection of Environmental Toxic ity Data from New Chemical Submissions Under Sec. 5," Unpublished, Environmental EffectsBranch, Health and Environmental Review Division (TS-796),U. S. Environm ental Protection Agency, W a shington, DC. Sigman, C.C., Helms, C.T., Papa, P.A., Atkinson, D.L., Doeltz, M.K. and W i nship-Ball, A., Jan. 1983, "Anthraquinone Dyes and Related Chemicals: Review and Assessment of Potential Environmental and Health Aspects," Final Report to the Dyes Environmental and Toxicology Organization, Inc., SRI International, Menlo Park, CA. Tonogai, Y., Ito, Y., Iwaida, M., Tati, M., Ose, Y. and Sato, T., 1979, "Studies on the Toxicity of Coal-Tar Dyes. II. Examination of the Biological Reaction of Coal-Tar Dyes to Vital Body," The Journal of Toxicological Sciences , Vol. 4, pp. 211-219. July, 1991; revised June, 1994

4Category: Acrylamides Hum a n Health and Environmental Toxicity
Definition. Any new chemical with the following structure is considered to be a m emb er of the category:

A typical acrylamide in the new chemical program is used as a monomer and has a mo lecular weight of < 500. The acrylamides of greatest concern are those with a labile substituent, e.g., m e thylol acrylamides, that m a y release acrylamide per se under m e tabolic conditions. For toxicity to aquatic organisms, there is a concern f o r all substituted acrylamides with m o lecular weights of <1000 and log Kow of <8.0.
Haz a rd Concerns. Based on analogy to acrylamide per se , m emb ers of the class are considered potential carcinogens, heritable m u tagens, reproductive and developmental toxicants, and toxic to aquatic organisms. Acrylam i des are also potential neurotoxins based on data for a number of low m o lecular weight acrylamides.
Boundaries. Structures with an acrylamide equivalent weight of > 5,000 are presumed not to pose a hazard under any conditions. Typically, concerns are confined to those species with mo lecular weights <1,000 whenever inhalation (or environmental) exposure is expected, and to species <500 when dermal, but not inhalation, exposure to humans is expected. Occupational Exposure Controls. Because acrylamides are expected to be absorbed via the dermal route, glove permeation testing conducted in accordance with standard ASTM testing protocols m a y be required, depending upon estimated workplace exposures and the hazard identified f o r the particular acrylamide submitted as a PMN.

5General Testing Strategy . Tier 1. To properly assess human and environm ental toxicity or exposure, certain physicalchemical or environmental fate properties need to be measured: water solubility (40 CFR §796.1860) Kow (40 CFR §796.1570 or 40 CFR §796.1550) vapor pressure (40 CFR §796.1950) m e lting point-melting range (OECD 102 or OPPTS 830.7200) Aerobic biodegradability can be determined using one of the following test guidelines, listed in approxim a te order of preference: Aerobic aquatic biodegradation Modified Sturm test Closed bottle test Modified OECD screening test Modified MITI test (I) Modified AFNOR test 40 CFR 796.3100 40 CFR 796.3260 40 CFR 796.3200 40 CFR 796.3240 40 CFR 796.3220 40 CFR 796.3180 The physical state and electronic charge of the PMN substance should also be reported. Tier 2. EPA considers the following tests to be the m o st appropriate for acrylamides found to pose an unreasonable risk to hum an health: - 90-day subchronic toxicity (40 CFR §798.2650) with functional observational battery (40 CFR §798.6050) and neuropathology (40 CFR §798.6400). - A rodent dominant lethal assay (40 CFR §798.5450). If positive, a rodent heritable translocation test (40 CFR §798.5460) would be the appropriate followup test. - A 2-year carcinogenicity test (40 CFR §798.3300) in rats and m i ce. To address environmental toxicity concerns, the following testing is recomme nded, for acrylamides with log Kow <5 : acute aquatic toxicity testing in algae, daphnid, and fish. The acute toxicity tests for fish (40 CFR 797.1400) and daphnids (40 CFR 797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control <2 m g TOC/L; the highest treatm e nt concentration on a mean m easured-basis should equal the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. The algal toxicity testing (40 CFR 797.1050), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and

696 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; and the highest treatm e nt concentration on a mean measured-basis equal to the aqueous solubility limit. Solvent can be used to assist the PMN substance to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN substance beyond its aqueous solubility limit. For acrylamides with log Kow >5 and <8 , aquatic toxicity testing should be for chronic effects only: (1) fish chronic toxicity testing, i.e., fish early life stage (ELS) toxicity testing with rainbow trout (40 CFR 797.1600), with flow-thr ough m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; and statistical analysis of effective concentrations at days 30, 45, 60, 75, and 90; (2) daphnid chronic toxicity testing (40 CF R 797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m e an m easured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; and (3) algal toxicity testing (40 CFR 797.1050), with static m e thods; measured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test me dium with at least 0.300 m g /L EDTA as a final concentration; and the highest treatment concentration on a mean measured-basis equal to the aqueous solubility limit. Solvent can be used to assist the PMN substance to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN substance beyond its aqueous solubility limit.
Novem b er 1990; revised July 1993; revised October 1995

7Category: Acrylates/Methacrylates Environmental Toxicity (Human Health, case-by-case) Definition. Any m o lecular structure containing one or m o re of the following reactive groups is considered to be a m emb er of the class:
O 5 - acrylate, CH 2 =CH-C-O-

O 5 - methacrylate, 	CH 2 =C-C-O­ | CH 3

Haz a rd Concerns.
Hum a n Health: As a result of testing conducted under an agreement between the Agency and the Specialty Acrylates and Methacrylates (SAM) Panel of the Chemical Manufacturers Association (CMA), EPA no longer controls new chemical acrylates or m e thacrylates as a category based on health concerns. However, if a new acrylate is structurally similar to a substance for which EPA has positive toxicity data, EPA m a y regulate that substance under TSCA section 5(e) based on its potential unreasonable risk. This will be done on a case-by-case basis and is expected to effectively eliminate m o st regulation of acrylates, especially higher mo lecular weight and polymeric substances. Despite the fact that EPA no longer expects to ma ke a potential unreasonable risk to human health finding for m a ny of the new acrylates, EPA still recomme nds the use of engineering controls or personal protective equipment to reduce exposures in the workplace in recognition of their potential as irritants and sensitizers. Environmental Toxicity: The ecotoxicity of acr ylates and m e thacrylates is a function of the octanol-water partition coef fi cient. They exhibit sim p le narcosis at log P' s >5, but display excess toxicity at lower log P's. The toxicity of acrylates and m e thacrylates can be predicted by a QSAR (quantitative structure-activity relationship), although there are som e memb ers of the class such as allyl m e thacrylate that are significantly m o re toxic than predicted by the QSAR.
Boundaries. Typically, environmental toxicity concerns are confined to those species with mo lecular weights <1,000. Acute and chronic toxi city is possible at log P’s <5, and chronic toxicity is possible at log P’s <8. General Testing Strategy Tier 1. To properly assess environmental toxicity or exposure, certain physical-chem i cal or environmental fate properties need to be measured:
8water solubility (40 CFR §796.1860) log Kow (40 CFR §796.1570 or 40 CFR §796.1550) vapor pressure (40 CFR §796.1950) me lting point-melting range (OECD 102 or OPPTS 830.7200) aquatic biodegradation (40 CFR §796.3100). The physical state and electronic charge of the PMN substance should also be reported. Tier 2. To address environmental toxicity concerns, the following testing is recomme nded: acute aquatic toxicity testing in algae, daphnid, and fish (all tests using m e asured concentrations; algae: static m e thod, daphnid and fish: flow-through m e thod). Septem ber, 1988; Revised July, 1993 and January, 1997.

9Category: Aldehydes Environmental ToxicityAldehydes are a class of organic compounds characterized by the functional group RC(=O)-H. Aldehydes are ionizable in water and exhibit excess aquatic toxicity in addition to narcosis. Polyaldehydes are m o re toxic than monoaldehydes to aquatic organisms and acrylic/vinyl/allylic aldehydes , e.g., acrolein, are m o re toxic than polyaldehydes. Vinyl/allylic/acrylic aldehydes are a class of organic compounds characterized by both the aldehyde, R-C(=O)-H, and vinyl, H 2 C=C-R, or allylic, R-C=C-R, functional groups. Allylic and vinyl aldehydes, e.g., acrolein, C=CC(=O), exhibit excess toxicity. It is assum e d that aldehydes need to be absorbed to be toxic, therefore, aldehydes with MW >1000 will be excluded from this category. Acute toxicity for aldehydes is known to be limited by the octanol/water partition coef fi cient (K ow ). Above a log K ow value of >6.0, aldehydes show no effects at saturation during 96-h exposures to fish. Aldehydes which are solids at room tem p erature m a y show no toxicity at saturation at lower K ow values depending on the m e lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no toxicity will be observed at saturation. For solids, the no effects at saturation has to be determined on a case-by-case basis. There are no measured upper K ow limits f o r chronic toxicity at this time, but it m a y not be m u ch above a log K ow = 8. Future testing will determine K ow limits.
Haz a rd Concerns : The toxicity for aldehydes has been determ ined through SAR Analysis: SARs for monoaldehydes : log fish 96-h LC50 (moles/L) = -0.449 log K ow -3.314 where n=54, R2 =0.53, CLOGP<6, MW<1000; log daphnid 48-h LC50 (millimoles/L) = -0.059 -0.608 log K ow where n=5, R2 =1.0, CLOGP<6, MW<1000; log green algal 96-h EC50 (mmo l/L) = 0.994 -0.812 log K ow (CLOGP) where n=2, R2 =1.0, CLOGP<6.4, MW<1000; log fish ChV (millimoles/L) = -0.810 -0.680 log K ow (CLOGP) where n=3, R2 =0.97, CLOGP<8, MW<1000; log daphnid ChV (millimoles/L) = -1.090 -0.576 log K ow (CLOGP) where n=2, R2 =1.0, CLOGP<8, MW<1000; and log algal ChV (mmo l/L) = 0.053 -0.644 log K ow (CLOGP) where n=5, R2 =0.99, CLOGP<8, MW<1000. SARs for polyaldehydes :

10log fish 96-h LC50 (millimoles/L) = -1.176 -0.371 log K ow (CLOGP) where n=2, R2 =1.0, CLOGP<6, MW<1000; log fish 96-h LC50 (millimoles/L) = -1.021 -0.396 log K ow (SRC) where n=2, R2 =1.0, SRC<6, MW<1000; log daphnid 48-h LC50 (mmo l/L) = -1.059 -0.440 log K ow (CLOGP) where n=2, R2 =1.0, CLOGP<6, MW<1000; log daphnid 48-h LC50 (mmo l/L) = -0.875 -0.471 log K ow (SRC) where n=2, R2 =1.0, SRC<6, MW<1000; log green algal 96-h EC50 (mmo l/L)= -1.772 -0.364 log K ow (CLOGP) where n=3, R2 =0.99, CLOGP<6.4, MW<1000; log green algal 96-h EC50 (mmo l/L)= -1.620 -0.388 log K ow (SRC) where n=3, R2 =0.99, CLOGP<6.4, MW<1000; log fish ChV (millimoles/L) = -2.298 -0.488 log K ow (CLOGP) where n=2, R2 =1.0, CLOGP<8, MW<1000; log fish ChV (millimoles/L) = -2.092 -0.513 log K ow (SRC) where n=2, R2 =1.0, CLOGP<8, MW<1000; log daphnid ChV (millimoles/L) = -1.798 -0.488 log K ow (CLOGP) where n=2, R2 =1.0, CLOGP<8, MW<1000; log daphnid ChV (millimoles/L) = -1.592 -0.513 log K ow (SRC) where n=2, R2 =1.0, CLOGP<8, MW<1000; log algal ChV (millimoles/L) = -2.313 -0.348 log K ow (CLOGP) where n=2, R2 =1.0, CLOGP<8, MW<1000; and log algal ChV (millimoles/L) = -2.166 -0.367 log K ow (SRC) where n=2, R2 =1.0, CLOGP<8, MW<1000 SARs for vinyl/allylic/acrylic aldehydes : log fish 96-h LC50 (mmo les/L) = -3.502 +0.017 log K ow (CLOGP) where n=3, R2 =0.25, CLOGP<6, MW<1000; and log fish ChV (millimoles/L) = -4.377 -0.228 log K ow (CLOGP) where n=2, R2 =1.0, CLOGP<8, MW<1000.

11Environmental Fate :

Boundaries : MW <1000. Log K ow <6.4 for toxicity to green algae as a 96-h EC50; and log K ow assum e d to be <8.0 for chronic toxicity to aquatic organisms, but could be higher. <6.0 for acute toxicity to fish and aquatic invertebrates; log K ow General Testing Strategy : I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity tests for fish (CFR §797.1400) and daphnids (CFR §797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; ideally, m e an measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; and solvent can be used to assist the aldehyde to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the aldehyde beyond its aqueous solubility limit. Stock solutions in water should be adjusted to pH near 7.0. The algal toxicity testing (CFR §797.1050), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; ideally, mean m easured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; and solvent can be used to assist the aldehyde to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the aldehyde beyond its aqueous solubility limit. Stock solutions in water should be adjusted to pH near 7.0. If there is no significant risk from the aldehyde after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180

12If there is no significant risk from the aldehyde after the results of biodegradation testing have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 3. Tier 3. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (CFR §797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; m easured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because the 7-d ELS toxicity test m a y underestimate chronic toxicity measured by the 28-d ELS toxicitytest when the Chronic Values are com p ared. Stock solutions in water should be adjusted to pH near 7.0. Daphnid chronic toxicity testing (C FR §797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean m easured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substitu ted for the 21-d toxicity test because the fish 7-d ELS toxicity test m a y underestimate chronic toxicity measured by the fish 28-d ELS toxicity test when the chronic values are com p ared.
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay. July, 1996

13Category: Aliphatic Amines Environmental Toxicity This category includes primary amines, secondary amines and tertiary amines; or monoalkyl amines, dialkly amines and trialkyl amines, respectively. This group includes alkanes, alkenes and alkynes; substitutions on carbon (alkyl) chains m a y include but not be limited to halogens and hydroxyls; insertions in alkyl chain m a y include but not be limited to ethoxys, propoxys, ethers, sulfides, disulfides and polysulfides; amine oxides are also included in this category; fatty polyam i nes (e.g., diamines, triam i nes, tetraamines, pentamines, etc) are also included; amines m a y either be un-ionized (free) or i onized; and strong ion pairs m a y also be included.

Haz a rd Concerns: Mem b ers of this category can be highly toxic to all groups of freshwater organisms (i.e., fish, aquatic invertebrates and green algae). Toxicity is related to the length of the hydrophobic carbon chains: the longer (or greater the number of carbons) the chain the m o re toxic to aquatic organisms when the number of amines is constant; and the greater the number of amines, the greater the toxicity given a constant carbon chain length. Small aliphatic amines are mo re toxic to algae than fish and invertebrates; higher m o lecular weight amines are equally toxic to all aquatic organisms. Small aliphatic amines which are un-ionized are m o re toxic to fish than when they are ionized; toxicity to algae appears to be unaffected by ionization. Strong ion pairs are generally m u ch less toxic to fish and invertebrates because of solubility limitations, but rem a in highly toxic to green algae. The toxicity of each amine will be predicted using structure-activity relationships (SARs) and analogs contained in a generic standard environmental hazard review for aliphatic amines.
Boundaries: There are no lower boundaries and the upper boundary is unknown at this time. It is known that a C13-NH3 Cl is still toxic to fish at less than 1 m g /L. An upper boundary for carbon chain length will probably be about 20 carbons but m o re information is needed at this time. Generally, m emb ers of this category will have m o lecular weights less than 1000.

14General Testing Strategy Tier 1. The base set of environmental toxicity tests in clean dilution water and two fish acute toxicity tests done in the presence of humic acid (i.e., TOC) will be recom me nded. These test will be done under static m e thods with nominal concentrations. Smaller amines (e.g., Schiff bases) are expected to demonstrate less mitigation by humic acid (larger log P, greater m itigation; increase log P correlates to increased MW). If hydrolysis 1/2 life is less than one hour, test the hydrolysis product; if it is greater than one hour, test parent m a terial. Tier 2. If TOC significantly reduces the toxicity to water columnspecies, then toxicity testing f o r toxicity to benthic organism s (i.e., organisms that ingest sedim e nt) will be recomme nded; however, if TOC does not significantly reduce the toxicity to water column species, then chronic toxicity with f i sh and aquatic invertebrates will be recomme nded as well as aerobic biodegradation testing. Aerobic biodegradability can be determined using one of the following test guidelines, listed in approxim a te order of preference: Aerobic aquatic biodegradation Modified Sturm test Closed bottle test Modified OECD screening test Modified MITI test (I) Modified AFNOR test
September 1988; revised Novem b er 1995. 40 CFR 796.3100 40 CFR 796.3260 40 CFR 796.3200 40 CFR 796.3240 40 CFR 796.3220 40 CFR 796.3180

15Category: Alkoxysilanes Hum a n Health Environmental Toxicity Definition. Any m o lecular structure containing one or m o re of the following reactive groups is considered to be a m emb er of the category. | | -C-O-Si­ | | The "typical" new chemical of concern is a polymer with a substantial fraction of species with mo lecular weights <1000 and pendant trimethoxy- or triethoxysilane groups.
Haz a rd Concerns. Health- Concern for lung toxicity from inhalation of vapors or aerosols is based on data for a number of low-m o lecular-weight alkoxysilanes. Trimethoxysilane (TMS) is clearly the mo st toxic m emb er of the class causing irreversible lung effects at low doses, but the Agency does not consider it appropriate to use TMS as a regulatory benchmark for all alkoxysilanes. For trimethoxysilane monomers and polymers with a low trimethoxysilyl equivalent weight, a NOAEL of 10 ppm (about 11 mg /kg/day) based on a 90-day study with vinyltrimethoxysilane in monkeys is deemed an appropriate generic benchmark. Alkoxysilanes in which the alkyl substituent is not a m e thyl group do not appear to be as toxic as m e thoxysilanes. The New Chemicals Program currently uses a generic benchmark NOAEL of 75 m g /kg/day, based on a 90-day inha lation study with tri(isopropenoxy)silane, for alkoxysilanes other than m e thoxysilanes. Ecotoxicity- Alkoxysilanes are highly toxic to algae and moderately toxic to aquatic invertebrates. For example, the daphnid 48-hr LC 50 for dim e thyldiethoxysilane is 1.25 m g /L, and the 15-day algal EC 95's for vinyltriethoxysilane, tetraethoxy-silane, and trifluoropropenyl(methyl)diethoxysilane are all approxim a tely 10 

### : g/L.
Boundaries. Methoxy- and ethoxysilanes are presumed not to pose a hazard under any conditions if the equivalent weight is 

### $ 5,000 and no m o re than 25% of species have m o lecular weights less than 1,000 and no m o re than 10% of species have m o lecular weights less than 500. For alkoxysilanes with alkyl substituents larger than propyl groups, the equivalent weight cutoff is 1,000. The degree of concern depends on the relative abundance of lower m o lecular weight species, but there is no m o lecular weight threshold above which there would be no concern. To better define the boundaries of the category, EPA seeks testing on a limited number of alkoxysilanes that focuses on (1) the relationship between m o lecular weight (or alkoxysilyl equivalent weight) and inhalation toxicity and (2) the importance of increasing alkoxy chain length in lim iting toxicity.

16General Testing Strategy The Agency recomme nds the following testing as appropriate to address health and environmental toxicity concerns for this category: 1. 90-day subchronic test in rodents by the inhalation route (40 CFR 798.2650). 2. Hydrolysis testing (40 CFR 796.3500). If t 1/2 is less than one hour, base set ecotoxicity testing (see "3," below) is conducted with the hydrolysis products only. If t 1/2 is greater than one hour, base set ecotoxicity testing is conducted with the parent m a terial; the PMN submitter has the option of also testing with the hydrolysis products. 3. Base-set ecotoxicity testing to include fish (40 CFR 797.1400) using the static m e thod, daphnids (40 CFR 797.1300) using the static me thod and algae (40 CFR 797.1050) using the static m e thod, all nominal concentrations. Direct dilution of the test alkoxysilane and organism s is added within 10 m i nutes. The static-renewal m e thod is used for fish and daphnid test, plus an additional fish test using aged stock solution. Results of the acute ecotoxicity testing m a y trigger chronic fish (40 CFR 797.1600) and daphnid (40 CFR 797.1350) testing. 4. Physical-chem i cal or environmental fate testing including, as appropriate, m e lting point (40 CFR 796.1300) or boiling point (40 CFR 796.1220), water solubility (40 CFR 796.1840 or 796.1860), log K ow (40 CFR 796.1550, 796.1570 or 796.1720), vapor pressure (40 CFR 796.1950), direct photolysis and indirect phot olysis (40 CFR 796.3765). Need for water solubility, log K ow , and photolysis testing determined by outcom e of above hydrolysis testing. September, 1988; revised June, 1994

17Category: Aluminum Compounds Risk Management Statement. Greatest concern is for soluble forms of aluminum (Al). If water solubility is greater than 1 part per billion (1 ppb), the Agency will prohibit releases of the PMN substance to water pending the submission of environmental toxicity testing.
Definition. This category includes inorganic salts of Al, com p lexes between Al and organic acids or chelates of Al by polyanionic monom er s, and organoAl compounds, i.e., Al covalentlybonded with carbon. For example, som e inorganic Al salts include: Al hydroxide, Al chloride, Al fluoride, Al nitrate, Al phosphate, and Al su lfate. Not included in this category are dyes com p lexed with Al (see dye categories addressed elsewhere within this “TSCA New Chemicals Program Chemical Categories” document).
Haz a rd Concerns. Soluble salts of Al are known to be highly toxic to green algae and m oderately toxic to fish and aquatic invertebrates at pH values between 6.5 to 9.0 and in terms of soluble Al in m g Al/L. Toxicity information are available for Al chloride, Al sulfate, and Na aluminate. The Office of W a ter (USEPA, 1988, EPA440/5-86-008) cited Seipt et al. (1984, Wa ter Air Soil Pollut. 23:81-95) who concluded that "the sim p le hydroxides (Al(OH) 2+ and Al(OH) 2 + ) are regarded as the m o st dangerous forms while organically bound Al and polymeric forms are less toxic or essentially harmless." The Office of W a ter (USEPA, 1988) also concluded that solutions of Al in water approach chemical equilibrium rather slowly and that Al can form strong com p lexes with fulvic and humic acids. The toxicity profile for soluble Al salts , listed below, is based on (1) available m e asured (M) toxicity data, (2) m g Al/L (ppm Al), (3) pH between 6.5 and 9.0, and (4) moderate hardness (about 150.0 m g /L as CaCO 3 ). fish (FHM) 96-h LC50 = 35.0 M pH7.3 H220 fish (RT) 96-h LC50 = 8.6 M pH7.5 H47 fish (RT) 96-h LC50 = 7.4 M pH6.6 H47 fish (RT) 96-h LC50 = 14.6 M pH7.3 H47 m ean RT 96-h LC50 = 10.0 P n3 fish (BT) 96-h LC50 = 3.6 M pH6.5 H? mean fish 96-h LC50 = 11.0 P n3 daphnid (Cd) 48-h LC50 daphnid (Cd) 48-h LC50 mean Cd 48-h LC50 daphnid (Dm) 48-h LC50 daphnid (Dm) 48-h LC50 m ean Dm 48-h LC50 m ean daphnid 48-h LC50
OW FW Acute W QC = 1.9 = 3.7 = 2.7 = 3.9 = 38.0 = 12.0 = 5.7

= 1.5 M pH7.4 H50 M pH7.7 H47 P n2 M pH7.0 H45 M pH7.1 H220 P n2 P n2

18---------------------------------------------------

--------------------------------------------------- green algal 96-h EC50 green algal 96-h EC50 m ean algal 96-h EC50 fish (FHM) ChV fish (FHM) ACR daphnid (Dm) ChV daphnid (Dm) ChV m ean Dm ChV Dm ACR daphnid (Cd) ChV Cd ACR m ean daphnid ChV m ean daphnid ACR OW FW Chronic W QC algal ChV Biological Fate = = =

= =

= = = = = = = =

=

= 0.570 M pH7.6 H15 0.460 M pH8.2 H15 0.510 P n2 3.3 M pH7.7 H220 11.0 M 0.742 M pH8.3 H220 0.320 M pH7.7 H45 0.490 P n2 24.0 M

1.9 M pH7.2 H50 1.4 M 0.970 P n2 5.9 M
0.087
0.100 P EC50÷4

Fish (BT-eyed embryo) 30-d BCF (wb) = 50.0 M pH7.2 H242 Fish (BT-fry) 30-d BCF (wb) = 136.0 M pH7.2 H242 m ean fish BCF = 93.0 P n2 The toxicity profile for soluble inorganic com p lexes of Al can be predicted via MW adjustm e nt of the toxicity f o r Al to the toxicity of the com p lex. Ca Al hydroxy phosphites [141 728-04-3] Ca x Al 2 (OH) 2 (x+3-y) (HPO 3 ) y 

### @ mH 2 O with x = 2 to 12, (2x+5)÷2 >y>0, and m = 0 to 12; typical composition = 31% Ca, 9.5% Al, & 8.0% P; solid with m p >250 °C (dec); S = 680 m g /L; pH 11.5; Concentration (mg/L) Effect

---------------------------- Com p lex Al Notes fish 96-h LC50 120.0 11.0 P fish 96-h LC50 409.0 6.0 M daphnid 48-h LC50 60.0 5.7 P daphnid 48-h LC50 24.0 nm M green algal 96-h EC50 5.4 0.510 P fish ChV 35.0 3.3 P

19---------------------------------------------------

--------------------------------------------------------------

--------------------------------------------------------------

-------------------------------------------------------------- daphnid ChV 10.0 0.970 P algal ChV 1.0 0.100 P

Na Al fluoride [15 096-52-3] sodium fluoalum i nate; sodium fluoride aluminum ; cryolite; kryolith; M12,2673; Na 3 Al F 6 ; MW210; composition: 13% Al; solid with m p 1000 °C; S = 610 m g /L with pH 6.2; used as an insecticide since 1929; Concentration (mg/L) Effect

------------------------------------------- Com p lex Al N otes fish 96-h LC50 85.0 11.0 P fish 96-h LC50 21.0 2.8 M daphnid 48-h LC50 44.0 5.7 P green algal 96-h EC50 3.9 0.510 P fish ChV 25.0 3.3 P daphnid ChV 7.5 0.970 P algal ChV 0.770 0.100 P

The toxicity profile for chelates of Al with polyanionic monomers can be predicted via MW adjustm e nt of the toxicity for Al to the toxicity of the chelate. The toxicity profile for organoAl compounds are developed for only the hydrolysis product(s) of Al. OrganoAl compounds are unstable in air and water. MethylAl and ethylAl are pyrophoric and dodecylAl slowly hydrolyses in water.
Boundaries. The toxicity of Al compounds depends on the their water solubility, the bioavailability of Al, and their stability. The m o st important property determining the toxicity of Al compounds is water solubility. Wa ter solubility cannot be predicted accurately and has to be m easured. Molecular weight (MW ) is only important when Al com p lexes are water soluble and stable. Stable com p lexes of Al with MWs > 1000 are not expected to be absorbed by aquatic organisms and Al is not expected to be bioavailable even if they are water soluble. Therefore, only unstable Al compounds with MWs < 1000 are expected to be toxic. General Testing Strategy Tier 1. Fate testing

. Physical state (OPPTS 830.6303) and corresponding property, i.e., me lting point-melting point range (OPPTS 830.7200) or boiling point-boiling point range (OPPTS 830.7220), water solubility (OPPTS 830.7840 or 7860), octanol/water partition coefficient (K ow ) (OPPTS 830.7550 or 7570), and vapor pressure (OPPTS 830.7950); and/or

20Acute environmental toxicity testing

. The aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures: fish acute t oxicity, daphnid acute toxicity, and green algal toxicity. The acute toxicity tests for fish (40 CFR §797.1400 or OPPTS 850.1075) and daphnids (40 CFR §797.1300 or OPPTS 850.1010) will be done using the static m e thod; effective concentrations will be based on 100% active ingredients (ai) and nominal concentrations; the total organic carbon (TOC) concentration of dilution water in the control m u st be less than 2.0 mg TOC/L; TOC m u st be measured in the control just prior to the start of the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; solvent can not be used; and hardness of dilution water has to be less than 180.0 m g /L as CaCO 3 . The algal toxicity testing (40 CFR §797.1050 or OPPTS 850.5400), should be done with the static m e thod; effective concentrations based on 100% ai and nominal concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with no mo re than 0.300 m g /L EDTA as a final concentration; the TOC of the test/growth m e dium should be less than 2.0 m g TOC/L; TOC should be measured just prior to the start of the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; and solvent can not used;

. In addition fish-toxicity-mitigation testing (OPPTS 850.1085) with known amounts of humic acid (HA) added to dilution water, i.e., 20 m g HA/L and 10 m g HA/L, will be recomm e nded. If there is no significant risk from the Al compound after the results of tier one testing set have been integrated into the risk assessment, then no f u rther testing will be recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Fate testing

. Aerobic biodegradation, i.e., ready biodegradation (OPPTS 835.3110) or sealed-vessel test (OPPTS 835.3120); and/or Fish chronic toxicity testing , i.e., fish early life stage (ELS) toxicity testing (40 CFR §797.1600 or OPPTS 850.1400), with the flow-through m e thod; effective concentrations based on 100% ai and mean measured concentrations of soluble Al; statistical analysis of effective concentrations at days 7, 14, 21, and 28; the TOC of dilution water in the control should be less than 2.0 m g TOC/L; TOC should be measured in the controls just prior to and during the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; solvent can not be used; and hardness of dilution water has to be less than 180.0 m g /L as CaCO 3 ; and Daphnid chronic toxicity testing (40 CFR §797.1330 or OPPTS 850.1300), with the flowthrough m e thod; effective concentrations based on 100% ai and mean measured concentrations of soluble Al; statistical analysis of effectiv e concentrations at days 7, 14, and 21; the TOC of dilution water in the control should not exceed 2.0 m g TOC/L; TOC m u st be m e asured in the controls just prior to and during the test; the highest treatm e nt concentration on a nominal-basis

21should not exceed the aqueous solubility limit of the tested compound; solvent can not be used; and hardness of dilution water has to be less than 180.0 m g /L as CaCO 3 . II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests will be recomme nded for terrestrial exposures. The terrestrial base set includes: the early seeding growth test (40 CFR 797.2800 or OPPTS 850.4230), the earthworm toxicity test (40 CFR.795.150 or OPPTS 850.6200), the soil m i crobial comm unity bioassay (40 CFR 797.3700 or OPPTS 850.5100), and the avian acute oral t oxicity test (40 CFR 797.2175 or OPPTS 850.2100). Chronic toxicity testing for terrestrial organism s include: the plant whole life cycle test (OPPTS 850.xxxx), the plant uptake test (40 CFR 797.2850 or OPPTS 850.4800), and the avian reproduction test (OPPTS 850.2300).
Abbreviations. ACR10 = acute-to-chronic ratio = 10; ai = active ingredients; BCF = bioconcentration factor; BT = brook trout; Cd = Ceriodaphnia ; ChV = Chronic value; Dm = Daphnia magna ; EC = effective concentration; FHM = fathead m i nnow; FT = flow-through m e thod; FW = fresh water; H = hardness in m g CaCO 3 /L; H? = hardness unknown; LOEC = lowest-observed-effect concentration; M = measured concentrations; n# = sam p le size used in calculation of the mean; nm = not measured; NOEC = no-observed-effect concentration; OW = Office of Water; P = predicted; RT = rainbow trout; S = static m e thod; SAR = structure activity relationship; SR24 = static renewal m e thod with renewals every 24 h; TOC = total organic carbon; wb = whole body; WQC = water quality criterion; August, 1997

22Category: Aminobenz o thiaz o le Az o Dyes Hum a n Health Environmental Toxicity

Definition . A ny disperse azo dye containing the substructure 2-aminobenzothiazole or 2-(pamino)phenylbenzothiazole, or phenyl ring-substituted derivatives of the sam e , is considered to be a m emb er of the category.

Haz a rd Concerns . T here are oncogenicity/mutagenicity concerns for intact aminobenzothiazole azo dyes by analogy to dim e thyl aminostyryl benzothiazole and Butter Yellow-type dyes, such as 4-ethyl-N,N-diethylaminoazobenzene. In addition, there are liver and thyroid concerns for reduction products by an alogy to 2-aminothiazole, and neuro-toxicity concerns by analogy to chlorinated 2-aminobenzothiazole. Ecotoxicity concerns are generally chronic concerns only and are based on QSAR predictions for neutral organic compounds. Neutral organic compounds are an established ecotoxicity category, of which these dyes are part of the disperse dye subclass.
Boundaries . T he boundaries are not strictly defined. For a typical m emb er of the category, R = N- and/or ring substituted p-aminophenyl groups, and R2 1 = halogens or nitro groups. General Testing Strategy

The New Chemicals Program considers the following tests to be the m o st appropriate for aminobenzothiazole azo dyes found to pose an unreasonable risk:

- Invivo m ouse m i cronucleus assay in bone m a rrow by the i.p. route (40 CFR 798.5395). - 90-day subchronic toxicity test in rats by the oral route, with special attention to the thyroid and liver (40 CFR 798.2650).

23- Fish early life stage test (40 CFR 797.1600). Chronic daphnid test (40 CFR 797.1350). Algae toxicity test (40 CFR 797.1050). - If the mouse m i cronucleus assay is positive, further characterization of the potential cancer risk m a y be recomme nded: 2-year cancer bioassay by the oral route in 2 species of rodents (40 CFR 798.3260). Potentially significant ecotoxicity risk, as well as human health risks, resulting from releases to water ONLY , m a y be addressed by environm ental fate testing prior to the chronic ecotoxicity and human health testing. The results of the environmental fate testing m ay preclude the need for further testing. - Jar test to determine the settling rate and extent of removal of suspended solids f r om solution (draft protocol available). If the results of the jar test do not mitigate the health and/or ecotoxicity concerns, f u rther characterization of the environm ental fate of the dye m a y be recomme nded. - Coupled units test (40 CFR 796.3300).
January, 1992.

24Category: Anhydrides, Carboxylic Acid Hum a n Health
Definition. Any m o lecular structure containing one or m o re carboxylic acid anhydride groups is considered to be a m e mb er of the category for new chemical purposes. Mem b ers of the class include new carboxylic acid anhydrides as well as new oligomers, polymers, prepolymers, or reaction products of existing carboxylic acid anhydrides. As illustrated below, a typical new chemical carboxylic acid anhydride of concern is a polymer or oligomer containing a monomer such as m a leic anhydride.

Haz a rd Concerns. Carboxylic acid anhydrides are of concern for potential pulmonary sensitization based on data for phthalic, trimellitic, isopropylidene bis(phthalic), and sulfonyl bis(phthalic) anhydrides. Carboxylic acid anhydrides are also of concern for potential developmental or reproductive toxicity based on data for m a leic, succinic, and phthalic anhydrides.

Boundaries. Structures with a carboxylic acid anhydride equivalent weight of > 5,000 are presumed not to pose a hazard under any conditions. Typically, concerns for health effects are confined to those species with m o lecular weights <1,000. The new chemical program has thus far been concerned only with those carboxylic acid anhydrides with potentially significant inhalation exposure, and has pursued developmental toxicity only for low m o lecular weight (<500) carboxylic acid anhydrides which are thought to have a significant potential for systemic uptake via the lung. For pulmonary sensitization, extensive systemic uptake m a y not be necessary for a biological response and we have therefore sought to regulate som e oligomeric or polymeric carboxylic acid anhydrides only for that effect. General Testing Strategy The following tests are usually prescribed for carboxylic acid anhydrides found to pose a potentially unreasonable risk:

- P ulmonary sensitization by either the m e thod of Karol (Toxicol. Appl. Pharm a col. 68:229-241, 1983), or an equivalent m e thod.

- Oral developmental toxicity study in two species (40 CFR §798.4900). May, 1991

25Category: Anilines Environmental Toxicity This category includes all anilines, both monoanilines and polyanilines. It is assum e d that these compounds need to be absorbed to be toxic, therefore, compounds with MWs > 1000 will be excluded f r om this category. Acute toxicity f o r anilines which are liquids at room tem p erature is known to be limited by the octanol/water partition coefficient (K ow ). Above a log K ow value of => 7.38, anilines show no effects at saturation during 96-h exposures (Veith and Broderius (1987). Anilines which are solids at room tem p erature m a y show no toxicity at saturation at lower Kow values depending on the m e lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no toxicity will be observed at saturation. For solids, the no effects at saturation has to be determined on a case-by-case basis. There are no known Kow limits for chronic toxicity at this time, but it m a y not be m u ch above a log K ow = 8 for liquid anilines. Future testing will determine this K ow limit.
Haz a rd Concerns. The acute toxicity for anilines has been determined through SAR Analysis: fish 96-h LC50 (Veith and Broderius 1987); fish 14-d LC50 (Deneer et al 1987); fish 14-d LC50 (Herm e ns et al 1984); daphnids 48-h LC100 (Nendza and Seydel 1988a and 1988b); and green algal 96-h EC50 (Nendza and Seydel 1988a and 1988b).; The neutral organic SARs can be used to predict green algal 96-h EC50. Aromatic diamines (i.e., two amines on one benzene) and dinitroanilines are known to be m o re toxic than predicted by these SARs.
Mem b ers of this category exhibit toxicity rangi ng from low toxicity (i.e., > 100 m g /L) to high

ow , MW and substitutions (e.g., dinitroanilines). toxicity (i.e., < 1 m g /L) depending on their K
Environmental Fate

. Som e recent studies have shown that certain anilines are subject to rapid direct and indirect photolysis under environm entally realistic conditions (Leifer 1990).
Boundaries. There are no known lower boundaries. The upper boundaries will be based on K ow and MW

. Acute toxicity expected with log K ow < 7.38; no effects at saturation during 96-h exposures when log K ow >= 7.38. Chronic toxicity has no known upper bound for log K ow , but it is probably near 8. MW will be < 1000. The environmental base set of tests will be requested fo r aquatic releases and the terrestrial base set of tests will be recom me nded f o r terrestrial exposures. Wh en the log K ow is >= 7.38, chronic toxicity testing with fish and daphnids will be recomme nded.

26General Testing Strategy . I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity tests for fish (40 CFR 797.1400) and daphnids (40 CFR 797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should equal the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. The algal toxicity testing (40 CFR 797.1050), should be done with static m e thods; m easured concentrations.; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nominal-basis equal to the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. If there is no significant risk from the PMN after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Direct and Indirect Photolysis Screening Test (40 CFR 796.3765). If t1⁄2 < 2 days, go to Tier 3; if t1⁄2 > 2 days, go to Tier 4. Tier 3a. If t1⁄2 < 2 days and photolysis products are known and/or identified, then assess photolysis products for environmental hazards. Tier 3b. If t1⁄2 < 2 days and photolysis products are not known and/or identifiable, then prepare a stock solution of PMN using the sta ndard humic-containing solution described in the direct and indirect photolysis screening te st [40.796.3765 (b)(2) and (c)(2)], expose to sunlight for at least 6 half-lives (t1⁄2), and test photolysis products for toxicity with m o st sensitive species fr om environmental base set. For example, the m o st sensitive species f r om the environmental base set has an EC50 value = 2.0 m g PMN/L (based on 100% active ingredients [AI]), therefore, prepare a 5.0 m g PMN per liter stock solution based on 100% AI using the standard humiccontaining solution. This stock solution is exposed to sunlight for at least 6 half-lives to ensure that all of the PMN has been photolyzed, and then this stock solution is used to retest the m o st sensitive aquatic species to determine if the photolysis products of the PMN are m o re or less toxic that the PMN.

27Tier 4. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR 797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because Van Leeuwen et al ( 1990) have demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen); Daphnid chronic toxicity testing ( 40 CFR 797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; the highest treatment concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test because Van Leeuwen et al (1990) have demonstrated that the fish 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the fish 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay.

28References

. Deneer JW, Sinnige TL, Seinen W and Hermens JLM. 1987. Quantitative structure-activity relationships for the toxicity and bioconcentration factor of nitrobenzene derivatives towards the guppy ( Poeciliareticulata ). Aquatic Toxicology 10:115-129. Hermens J, Leeuwangh P, and Musch A. 1984. Quantitative structure-activity relationships and mi xture toxicity studies of chloro- and alkylanilines at an acute lethal toxicity level to the guppy, Poeciliareticulata

. Ecotoxicology and Environmental Safety 8:388-394. Leifer A. 1990 (14 Dec). Review of Section 5 test data for o -phenylenediam i ne, m phenyldiamine, and p -phenylenediam i ne. Mem o randum . Wa shington, DC: Exposure Assessment Branch, Exposure Evaluation Division (TS-798), Office of Toxic Substances, United Stated Environmental Protection Agency, 401 M St, SW, 20460-0001. Nendza M and Seydel JK. 1988a. Multivariate data analysis of various biological test system s used for the quantification of ecotoxic compounds. Quantitative Structure-Activity Relationships 7:165-174. Nendza M and Seydel JK. 1988b. Quantitative structure-activity relationships for ecotoxicologically relevant biotest systems and chemicals. Chemosphere 17:1585-1602. Van Leeuwen CJ, Adema DMM, and Hermens J. 1990. Quantitative structure-activity relationships for fish early life stag e toxicity. Aquatic Toxicology 16:321-334. Veith GD and Broderius SJ. 1987. Structure-toxi city relationships for industrial chemicals causing type (II) narcosis syndrome. In Kaiser KLE (ed), QSAR In Environmental Toxicology - II, p 385-391. Reidel Publishing Com p any. May, 1991

29Subcategory of Anilines: Dianilines Hum a n Health Environmental Toxicity
Definition. A PMN m u st have the following m i nim um structural requirem e nts to be considered a m emb er of this category: -it m u st have at least two phenyl rings w ith a bridging carbon, oxygen, nitrogen, or sulfur -each terminal phenyl ring m u st have a primary am ino group (or a group that can be readily m e tabolized to a primary amino group) either m e ta- or para- to the bridging atom Compounds with one or m o re additional phenyl ring(s), with or without ring substituents, and one or m o re bridging atom s are also included in the category.

Minim um Structure f o r Dianiline Category

The compounds of greatest concern are those having X = C, N, or O and n = 0 or 1.
Haz a rd Concerns: Mem b ers of the class are considered to be potential carcinogens and m

u tagens by analogy to 4,4'-methylendianiline, 4,4'-methylene bis(o-toluidine), and 4,4'

- oxydianiline. Class m emb ers are potential retinotoxic agents by analogy to 4,4'

- me thylenedianiline, 4,4'-oxydianiline, and the diaminodiphenyl alkane drugs and are also potential reproductive and systemic toxicants by analogy to 4,4'-methylenedianiline.

30General Testing Strategy The New Chemicals Program has considered the following toxicity tests to be the m o st appropriate for dianilines found to pose an unreasonable risk:
I. Exposure to Hum a ns - rat acute oral retinopathy screening study (protocol to be approved by EPA) - pigmented rat 90-day subchronic toxicity study by the oral (40 CFR 798.2650) or inhalation (40 CFR 798.2450) route to include histopathological examination of the eyes and reproductive organs (eyes to be examined by both light and electron m i croscopy) - 2-year carcinogenicity bioassay (40 CFR 798.3300) in rats and m i ce. In the 90-day subchronic toxicity study, the com p any m a y opt to carry a group of animals at each dose level for a 90-day recovery period to determ ine whether potential retinopathy is reversible.
For som e compounds in this class, short-term mu tagenicity testing m a y be appropriate. Wh en appropriate, specif i c testing will be determined by EPA m u tagenicity assessors on a case by case basis by referral to "short question." Wh ere the general population is at a significant risk from drinking water exposure (via surface water releases) to PMN chem icals of this class, the following fate testing m a y be appropriate: -direct and indirect photolysis 40 CFR 796.3765 and 796.3700 -aerobic aquatic biodegradation 40 CFR 796.3100 -see aniline category description f o r details Results of the above fate tests m a y mitigate concern for drinking water exposure to PMN of this class. However, fate test results W I LL NOT CHANGE AGENCY CONCERNS FOR OCCUPATIONAL EXPOSURE to PMNs of this category.
II. Release to Aquatic Ecosystem s Tier 1. Because of the above boundary conditions, and the need to assess human exposure as well as environmental toxicity, if there is insufficient knowledge about the water solubility of the dye, then it should be measured (40 CFR §796.1860). The fish and daphnid acute toxicity tests f r om the aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures. The acute toxicity tests for fish (40 CFR §797.1400) and

31daphnids (40 CFR §797.1300) will be done using the flow-through m e thod with measured concentrations, and effective concentrations will be based on 100% active ingredients (AI) and m ean measured concentrations. If there is no significant risk from the PMN after the results of the fish and daphnid acute toxicity tests have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Direct and Indirect Photolysis Screening Test (40 CFR 796.3765). If t1⁄2 < 2 days, go to Tier 3; if t1⁄2 > 2 days, go to Tier 4. Tier 3a. If t1⁄2 < 2 days and photolysis products are known and/or identified, then assess photolysis products for environmental hazards. Tier 3b. If t1⁄2 < 2 days and photolysis products are not known and/or identifiable, then prepare a stock solution of PMN using the sta ndard humic-containing solution described in the direct and indirect photolysis screening test [40 CFR 796.3765 (b)(2) and (c)(2)], expose to sunlight for at least 6 half-lives (t1⁄2), and test photolysis products for toxicity with m o st sensitive species from environmental base set. Tier 4. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR 797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; and statistical analysis of effective concentrations at days 7, 14, 21, and 28. Daphnid chronic toxicity testing ( 40 CFR 797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21. Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation Modified Sturm Test Closed Bottle Test Modified OECD Screening Test Modified MITI Test (I) Modified AFNOR Test
III. Release to terrestrial Ecosystem s : 40 CFR 796.3100 40 CFR 796.3260 40 CFR 796.3200 40 CFR 796.3240 40 CFR 796.3220 40 CFR 796.3180

The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded f or terrestrial exposures. Chronic toxicity testing fo r terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay.

32References American Dye Manufacturers Institute, Inc. (1974). "Dyes and the Environment: Reports on Selected Dyes and Their Effects," Vol. II, ADMI, New York. Auer, C.M., Nabholz, J.V. and Baetcke, K.P. (1990). "Mode of Action and the Assessment of Chemical Hazards in the Presence of Limited Data: Use of Structure-Activity Relationships (SAR) under TSCA, Section 5," Environmental Health Perspectives , Vol. 87, pp. 183-197. Little, L.W., and Lam b J.C., III (1972). "Acute Toxicity of 46 Selected Dyes to the Fathead Minnow, Pim e phales promelas , "Final Report to the American Dye Manufacturers Institute, Inc., UNC W a stewater Research Center, Departm e nt of Environmental Sciences and Engineering, School of Public Health, University of North Carolina, Chapel Hill, NC. Nabholz, J.V. (1990). "The OTS PMN ECOTOX Data Base: a Confidential Business Information (CBI) Collection of Environmental Toxicity Data from New Chemical Submissions Under Sec. 5," Unpublished, Environmental Eff ects Branch, Health and Environmental Review Division (TS-796), U. S. Environmenta l Protection Agency, W a shington, DC. Sigman, C.C., Helms, C.T., Papa, P.A., Atkinson, D.L., Doeltz, M.K., and W i nship-Ball, A. (Jan. 1983). "Anthraquinone Dyes and Related Chemicals: Review and Assessm ent of Potential Environmental and Health Aspects," Final Report to the Dyes Environmental and Toxicology Organization, Inc., SRI International, Menlo Park, CA. Tonogai, Y., Ito, Y., Iwaida, M., Tati, M., Ose, Y., and Sato, T. (1979). "Studies on the Toxicity of Coal-Tar Dyes. II. Examination of the Biol ogical Reaction of Coal-Tar Dyes to Vital Body," The Journal of Toxicological Sciences , Vol. 4, pp. 211-219.
August 1991; revised January 1995; revised October 1995

33Category: Anionic Surfactants Environmental Toxicity
Definition. Any m o lecular structure with a net negative charge and having surfactant activity is a m emb er of this category. The category includes for example, alkyl sulfonates, alkyl benzene sulfonates, alkyl silicic acids, alkyl phosphates, alkyl carboxylic acids, or com b inations of these anionic groups, e.g., alkyl sulfonate with carboxylic acid substitutions.

Haz a rd Concerns. Anionic surfactants are toxic to a wide variety of aquatic organisms. Toxicity increases exponentially with increasing carbon chain length up to 16 carbons [for linear alkyl sulfonate (LAS) surfactants], and then decr eases with additional carbons. At a chain length of 16 carbons, fish and daphnids are m o st sensitive, but at lower chain lengths green algae are mo re sensitive than fish and daphnids. There are a number of structure-activity relationships (SARs) to predict the toxicity of m emb ers of this category. Most are parabolic regression equations and others rely on nearest analog m e thodology.
Boundaries. There is no m o lecular weight boundary. Surfactants with m o lecular weights > 1000 are still toxic. Acute toxicity m a y be low, i.e., > 100 m g /L, if a strong cationic surfactant counterion and the anionic surfactant form a tight ion pair. Testing. To address ecotoxicity concerns, base set acute aquatic toxicity testing (green algae: static m e thod, daphnid and fish: flow -through m e thod, all measured concentrations). Tier 1. The acute aquatic base setof environmental toxicity tests will be recom me nded for aquatic exposures and the terrestrial base setof environmental toxicity tests (i.e., the early seeding growth test, the earthworm acute toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for any terrestrial exposures. Acute fish toxicity test Acute daphnid toxicity test Green algae toxicity test Early seedling growth test Earthworm acute toxicity test Soil m i crobial comm unity bioassay OPPTS 850.1075 OPPTS 850.1010 OPPTS 850.5400
OPPTS 850.4230 OPPTS 850.6200 O PPTS 850.5100

34Tier 2. If acute toxicity testing indicates a significant risk, then environmental fate testing in the form of aerobic biodegradation testing is recomme nded. Aerobic biodegradability can be determined using one of the following test guidelines, listed in approxim a te order of preference:
CO 2 evolution Closed bottle Modified OECD screening Modified MITI (I) DOC die-away Manometric respirometry O PPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 Tier 3. In addition, if acute toxicity testing indicates a significant risk, then chronic aquatic toxicity testing with f i sh and aquatic invertebrates will be recomme nded. Fish early life stage test OPPTS 850.1400 Daphnid chronic toxicity testing O PPTS 850.1300
September 1988, revised September, 1996

35Category: Azides Environmental Toxicity Azides are a class of chemicals consisting of both inorganic and organic compounds and characterized by the functional group N=N=N. Substitutions m a y be either m e tals or organic compounds, e.g., acetic acid and benzene. So far, only monomeric aromatic azide compounds have been submitted as PMNs. No aliphatic azides, e.g., alkyl azides, have been submitted as PMNs. Aliphatic azides m a y be too explosive to isolate, however, diazidoacetic acid ester is known to exist and has been tested in rats.
Haz a rd Concerns: It is assum e d that azides have to be absorbed to be toxic, therefore, azides with MW >1000 will be excluded from this category. Acute toxicity for monomeric azides is assum e d to be correlated and limited by the octanol/water partition coef fi cient (K ow ). Above a log K ow value of >5.0, azides are assum e d to show no effects at saturation during 96-hour exposures to fish. Organic azides which are solid s at room tem p erature m a y show no toxicity at saturation at lower K ow values depending on their m e lting point and/or their water solubility. For example, for organic azides, the higher the m e lting point at a given K ow , the greater the likelihood that no toxicity will be occur at saturation. For solids, no effects at saturation has to be determined on a case-by-case basis. There are no measured upper K ow limits f o r chronic toxicity at this time, but it m a y not be m u ch above a log K ow = 8. Future testing will determine K ow limits. The aquatic toxicity of organic azides has been determined through SAR Analysis: log fish 96-h LC 50 (millimoles/L) = -1.881 -0.124 log K ow where n=2, R2 =1.0, LOGKOW(SRC)<5, MW<1000; The toxicity for inorganic azides has to be determined by integrating the toxicity of Na azide with the toxicity of any other inorganic element, e.g., Pb, with a MW adjustm e nt for differences in toxicity between Na azide and the other inorganic element. Na azide [26628-22-8] has been tested by the USEPA ERL-Duluth: fathead m i nnow 96-h LC 50 = 5.46 m g /L based on a flow-through m e thod with 18 volume changes per day and nominal concentrations. The SAR for organic azides is based on (1) this toxicity value, (2) a calculated log K ow value of -6.3 using SRC's LOGKOW, and (3) no acute effects to fish at saturation assum e d to occur at a log K ow > 5.0 which is equivalent to a log fish 96-h LC 50 = -2.5 in millimoles per liter. CLOGP has a mi ssing fragm e nt constant for the azide group.
Environmental Fate: Na azide is known to hydrolyze in water to form hydrazoic acid (or , [7782-79-8], MW43, M12,4815). Hydrogen azide is extremely explosive according to Merck. In addition, azides can be transform e d to nitrenes by uvlight. hydrogen azide, NH 3

Boundaries: MW <1000. Log K ow 50 ; and log K ow assum e d to be <8.0 for chronic toxicity to aquatic organisms, but could be higher. <5.0 for acute toxicity to fish and aquatic invertebrates; log K ow <6.4 for toxicity to green algae as a 96-h EC

36General Testing Strategy : I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity test s for fish (OPPTS 850.1075) and daphnids (OPPTS 850.1010) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (ai) and mean measured concentrations; m easured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; and solvent can be used to assist the aldehyde to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the test chemical significantly above its aqueous solubility limit. The algal toxicity testing (OPPTS 850.5400), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (ai) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; ideally, mean m easured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; and solvent can be used to assist the aldehyde to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the test chemical significantly above its aqueous solubility limit. If there is no significant risk from the PMN chemical after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Aerobic biodegradabilityaccording to either of the following test guidelines: Ready Biodegradability OPPTS 835.3110 Sealed Vessel CO2 Production Test OPPTS 835.3120 If there is no significant risk from the PMN chemical after the results of biodegradation testing have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 3. Tier 3. Fish chronic toxicity testing , i.e., f i sh early life stage (ELS) toxicity testing (OPPTS 850.1400), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrati ons at days 7, 14, 21, and 28; me asured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN significantly above its aqueous solubility limit; and the 7-d ELS

37stage toxicity test cannot be substituted for the 28-d ELS toxicity test because the 7-d ELS toxicity test m a y underestimate chronic toxicity measured by the 28-d ELS toxicity test when the Chronic Values are com p ared. Daphnid chronic toxicity testing (O PPTS 850.1300), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN significantly above its aqueous solubility limit; and the 7-d daphnid short-term chronic toxicity test cannot be substituted for the 21-d toxicity test because the daphnid 7-d short-term toxicity test m a y underestimate chronic toxicity m easured by the 21-d toxicity test when the chronic values are com p ared.
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test [O PPTS 850.4230], the earthworm toxicity test [OPPTS 850.6200], and the soil m i crobial comm unity bioassay [OPPTS 850.5100]) will be recomme nded for terrestrial exposures. Chronic toxicity te sting for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay.
References: L’Abbe, G. (1969). Decomposition and addition r eactions of organic azides. Chemical Review, 69, 345-363. Scriven, E.F. (Ed.). (1984). Azides and nitrenes: Reactivity and utility. pp.95-204. New York: Academic Press.
September 1996

38Category: Benzotriazoles Environmental Toxicity
Definition. This category includes all benzotriazoles.
Haz a rd Concerns. The toxicity for benzotriazoles with -NH has been determined through SAR Analysis (Clem e nts 1988). Benzotriazoles with -NH are known to be m o re toxic than neutral organic chemicals, and this excess toxicity decreases with increasing K ow . The toxicity of benzotriazoles with aliphatic substitutions on the nitrogen are expected to act like neutral organic compounds. Other substitutions on the N, e.g., -SH, have to be evaluated on a case-by-case basis.
Mem b ers of this category exhibit toxicity rangi ng from low toxicity (i.e., > 100 m g /L) to high

ow , MW, and m e lting point. toxicity (i.e., < 1 m g /L) depending on their K
Boundaries

. There are no known lower boundaries. The upper boundaries will be based on K ow , MW, and m e lting point (mp). These compounds need to be absorbed to be toxic, therefore, compounds with MWs < 1000 are expected to cause toxicity, while compounds with MWs > 1000 are no expected to show toxicity at saturation. Acute toxicity for benzotriazoles which are liquids at room tem p erature is known to be limited by the octanol/water partition coef f i cient (K ow ). Above a log K ow value of 5.0, benzotriazoles show no effects at saturation during 96-h exposur es (Clem e nts 1988). Benzotriazoles which are solids at room tem p erature m a y show no toxicity at saturation at lower K ow values depending on the m e lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no acute toxicity will be observed at saturation. For solids, the no-effects-at-saturation point for acute toxicity has to be determined on a case-by-case basis. The K ow limit f o r chronic toxicity is set at a log K ow chronic toxicity testing will determine the K ow limit. = 8 for liquid benzotriazoles. For solids,
Therefore, acute toxicity is expected when log K ow =< 5.0 and MW < 1000; no effects at saturation during 96-h exposures are expected when log K ow > 5.0 and MW < 1000. The upper boundary for chronic toxicity is 8.0. Only chronic toxicity is expected when log K ow > 5.0 and < 8.0, and MW < 1000. Wh enever MW > 1000, no effects are expected at saturation because it is assum e d that benzotriazoles have to be absorbed to be toxic. Aerobic biodegradation is expected to be the dominant route of transform a tion in the environment.

39General Testing Strategy . I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity tests for fish (40 CFR §797.1400) and daphnids (40 CFR §797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested chemical; and solvent can be used to assist the chemical to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the chemical beyond its aqueous solubility limit. The algal toxicity test (40 CFR §797.1050) should be done with the static m e thod; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the chemical; and solvent can be used to assist the chemical to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the chemical beyond its aqueous solubility limit. If there is no significant risk from the benzotriazole after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recom me nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180 If there is no significant risk from the benzotriazole after the results of the aerobic biodegradation testing have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 3. Tier 3. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR §797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit for the chemical; solvent can be used to assist the chemical to reach its aqueous solubility limit quicker, but cannot
40be used to artificially enhance the water solubility of the chemical beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because Van Leeuwen et al (1990) have demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). Both anilines and benzotriazoles with -NH are m o re toxic than predicted based on narcosis alone, i.e., both benzotriazoles and anilines have excess toxicity due to a m o re specific mode(s) of toxic action. A seven day exposure m a y not allow enough time for this excess toxicity to be expressed either because of not enough exposure and/or not enough time for m e tabolic activation. Daphnid chronic toxicity testing ( 40 CFR §797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the chemical; solvent can be used to assist the chemical to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the chemical above its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test (Van Leeuwen et al 1990).
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test, the avian acute oral toxicity test, and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, the avian reproductive toxicity test, and the soil m i crobial comm unity bioassay. In addition, the fate test for Inherent Biodegradability in soil (40 CFR §796.3400) m a y be recomme nded.
References Clements, RG (editor). 1988. Estimating toxicity of industrial chemicals to aquatic organism s using structure-activity relationships. EP A-560-6-88-001. Wa shington, DC: Environmental Effects Branch, Health and Environmental Revi ew Division, Office of Toxic Substances (TS796), United States Environmental Protection Agency. Available from the National Technical Information Service, Springfield, VA 22161, PB89-117592. Van Leeuwen CJ, Adema DMM, and Hermens J. 1990. Quantitative structure-activity relationships for fish early life stag e toxicity. Aquatic Toxicology 16:321-334. March, 1992

41Category: Benzotriazole-hindered phenols Hum a n Health Environmental Toxicity (see “Phenols”) The predominant use of m emb ers of this category is as a UV light stabilizer in coating or plastic formulations.
Definition. Any m o lecular structure containing the following substructure is considered to be a me mb er of the category.

Note : Health ef f ects m a y vary depending on the nature of the ring substituents.
Haz a rd Concerns. I. Health Systemic toxicitybased on 8(e) and PMN data on analogues. These data are generally consistent across compounds, with the following endpoints occurring in subacute, subchronic, and chronic oral feeding studies in rats and dogs in which doses ranged from 5 to 15,000 ppm

. Increased organ weights (liver and kidney, w ith associated histopathology at higher doses); hem a tological effects (decreased hemoglobin, packed cell volume, and erythrocytes); and imm une system effects (weight changes in thymus, spleen, lymph nodes; decreased leukocytes). Generally, treatm e nt-related effects are dose-related, increasing in frequency and severity with increasing dose. Males appear to be m o re sensitive than f ema les, and similar toxic ef f ects occur in both rats and dogs. The lowest available NOAEL for systemic effects, from a 90-day rat study, is 5 ppm, or 0.25 mg/kg/day

. Reproductive toxicity- Concern is also based on 8(e) and PMN data on analogues. As with

42systemic toxiciy, the data are generally consistent, with the following endpoints occurring in subacute and subchronic oral feeding studies in rats and dogs in which doses ranged from 5 to 15,000 ppm. Atrophy of the sem i nal vesicles, significant reduction in absolute and relative testes weight, significant reduction in absolute and relative prostate weight, and abnorm a l sperm a togenesis. A subchronic dog study also provided evidence of fem a le reproductive toxicity. Generally, treatm e nt-related effects are dose-related, increasing in both frequency and severity with increasing dose. Males appear to be m o re sensitive than f em a les, and similar toxic ef f ects occur in both rats and dogs. The lowest NOAEL for reproductive toxicity, from a 90-day dog study, is 15 mg/kg/day

. Dermal sensitization- Dermal sensitization test data were positive in 3/4 compounds tested. Two of the compounds showed strong sensitizing potential based on results obtained from ma xim i zation tests in which 70% and 90% of the treated guinea pigs became sensitized, respectively. II. Environmental - The environmental concerns for the substances described in this category have already been described in the Phenol category. Boundaries. Not enough is known about the structure-activity relationships of these compounds to set any boundaries on m emb ers of the category; compounds with both "sm a ll" and "large" substituents have shown effects, and the effects are generally consistent from compound to compound. General Testing Strategy I. Health Systemic Toxicity and Reproductive Toxicity

. A 90-day gavage study in rats with special attention to hem a tology; weight and histopat hology of lymphoid organs (spleen, thymus, and bone m a rrow); cellularity of the bone m a rrow, thymus, and spleen; and histopathology of the liver, kidney, heart, and all endocrine glands fo r which weight changes are observed. Particular attention should be directed toward achieving satisfactory quality from fixation and embedding of the testes, f o llowing the recomme ndations of Russell et al. [ R ussell LD, Ettlin RA, Sinha Hikim AP, Clegg ED. 1990. Histological and hist opathological evaluation of the testis. Cache River Press, Clearwater, FL]. A gavage study, as opposed to an oral feeding study, is recomme nded because decreased body weight gain, final body weight, and/or food c onsumption have been reported in som e oral feeding studies with analogues.

43If imm unopathology and hem a tology in the 90-day study support the concern for adverse effects of the PMN substances on the imm une system, then a further battery of tests, such as the NTP's Imm unotoxicology Tier II Screening Panel, will be recomme nded. Dermal Sensitization

. Because dermal sensitization is not routinely pursued under TSCA 5(e) as a regulatory endpoint, testing is not recomme nded. A letter be sent to the PMN submitter expressing the Agency' s belief that the compounds are likely to be dermal sensitizers and that protective measures should be taken for workers. II. Environmental toxicity If exposure to the aquatic environment demonstrates a potential risk, testing of the substances described in this category is the sam e as that prescribed for the Phenols category. June, 1993.

44Category: Boron Compounds Human Health Environmental Toxicity
Definition. This category includes borates, organoborates, borate esters, boron hydrides, boranes, and boroxines.
Hum a n Health : Haz a rd Concerns. Reproductive toxicity (males/females), blood toxicity, and neurotoxicity

. The Agency has an oral RfD for boron of 0.09 mg/kg/day (uncertainty factor 100) based on the finding of testicular atrophy and sperm a togenic a rrest in dogs in a 2-yr feeding study (Weir and Fisher 1972, as summa rized in IRIS 1995). [All toxicity information presented here are summa rized in an assessment of various aqueous cleaner chemicals prepared in 1990 for the Office of Air and Radiation. Reproductive toxic ity information also summa rized in IRIS 1995.] Reproductive Toxicity

. The m o st significant effect seen in animals is reproductive toxicity (i.e., sterility in m a les and fem a les, and testicular atrophy in m a les). A three-generation reproductive study in rats demonstrated sterility in m a les (lack of sperm a tozoa in atrophied testes) and fem a les (decreased ovulation) after exposure to 58.5 m g boron/kg in the diet. NOAEL (rats) 17.5 m g boron/kg

. Sterility was also found in m a les (at 50 or 100 m g boron/kg) in a serial ma ting adjunct to a 60-day feeding study; NOAEL (rats) 25 m g boron/kg

. Data from oral subchronic and chronic studies in rats, dogs, and m i ce also provide evidence that boron produces adverse effects on the m a le reproductive system

. A statistically significant reduction in relative and absolute testes weights was seen in a 2-yr and a 90-day dietary study in ma le rats at 58.5 and 26.3 m g boron/kg, respectively. NOAEL’s (rats) 17.5 and 8.8 m g boron/kg, respectively

. In m a le rats, dietary exposure to 50 m g /kg boron resulted in a significant reduction in f e rtility, a signif i cant reduction in epididymal weight, and a reduction in sperm number after 30 days of treatm e nt. A significan t reduction in testicular weight and further reduction in sperm occurred after 60 days of treatm e nt. NOAEL (rats) 25 m g boron/kg

. Similar results were observed in several drinking water studies in rats.
In m a le dogs, dietary exposure to 29.4 m g boron/kg for 2 yr resulted in severe testicular atrophy and sperm a togenic arrest. NOAEL (dogs) 8.8 m g boron/kg

. In m a le and fem a le dogs, dietary exposure to 43.8 and 4.4 m g boron/kg for 90 days did not affect the fem a le reproductive system , but produced decreased testes weights (statis tically significant at 43.8 m g boron/kg). NOAEL (dogs) 0.4 m g boron/kg

. In m a le m i ce, dietary exposure to 131 m g boron/kg for 103 wk (only dose tested) caused an increased incidence of testicular atrophy and interstitial hyperplasia. Blood Toxicity

. In a chronic feeding study in rats, packed cell volume and hemoglobin levels were significantly decreased in m a les and fem a les at 58.5 m g boron/kg. NOAEL ( rats) 17.5 m g boron/kg

. In a subchronic drinking water study in rats, a significant decrease in plasm a triglyceride levels was noted at 23.7 and 47.4 m g boron/kg (only doses tested). LOAEL (rats) 23.7 m g boron/kg

. In a subchronic feeding study in dogs, 43.8 m g boron/kg but not 4.4 or 0.4

45mg boron/kg produced decreased packed cell volumes and hemoglobin levels. NOAEL (dogs) 4.4 m g boron/kg

. In a subchronic feeding study in m i ce, m i nim a l to mild extramedullary hem a topoiesis of the spleen was observed in all dosed groups (ca. 34, 68, 136, 272, or 544 m g boron/kg). LOAEL (mice) 34 m g boron/kg

. There is also a case study in which an infant exposed to 43 m g boron/kg/day for 12 weeks developed anemia. Neurotoxicity

. Ingestion of borax by human infants results in neurotoxicity. Case reports of nine infants who were exposed by sucking pacifiers dipped in a borax-honey m i xture document similar findings of neurological sym p tom s (not specified) and seizures. For seven infants, doses are reported as 2 to 3 g borax/wk for 4 to 10 wk (ca. 4 to 16 m g boron/kg/day ). Serum boron levels measured in three of the seven infants were elevated. For the other two infants, doses are reported as 125 m g borax/kg over a 12-wk period and 9 g borax over a 5-wk period (ca. 43 and 8 mg boron/kg/day , respectively). The effects appear to be reversible upon cessation of exposure. Neurotoxicity testing is not recomme nded because animal studies do not appear to be predictive of this effect.
Boundaries. The boundaries of this category are not yet well defined for health effects. All of the toxicity data are on boric acid or borax. A m o lecular weight cutoff of 1,000 is proposed, but there is no inf o rmation f r om available toxicity data on a proper water solubility cutof f. General Testing Strategy. The OECD reproductive toxicity screen (OECD 421) with special additional attention to hem a tology. If this screen is positive for reproductive toxicity, a reproductive fertility study in rats according to the OPPTS Harmonized Test Guidelines (870.3800) is recomme nded. In cases in which exposures are exclusively dermal, a dermal absorption study (either in vivo or in vitro) could be conducted to refine the dermal risk assessment. If the in vivo study is selected, the test m a terial should not be corrosive. If there is som e uncertainty as to the corrosivity of the neat test m a terial, a dermal irritation study should be undertaken first. If the neat m a terial is corrosive, dilution to a noncorrosive concentration with a vehicle such as acetone or the alcohol used to m a ke the ester is recomme nded. Environmental Toxicity : Most of the toxicity information for boron compounds is for boric acid and sodium tetraborate. These boron compounds show low acute toxicity towards fish (250.0 m g /L as a m ean acute toxicity value) and daphnids (70.0 m g /L as a mean acute toxicity value), but m oderate toxicity towards green algae (20.0 m g /L as a mean EC50 value). However, these compounds exhibit large acute to chronic ratios (ACR) towards fish (125 as a mean ACR) and the difference between the EC50 value and the chronic value (ChV) in green algae is large (about 117 as a mean difference). The mean ACR for daphnids is 8. The mean ChVs for fish, daphnids, and green algae are 2.0 m g /L, 9.0 m g /L, and 0.170 m g /L, respectively. Green algae appears to be the m o st sensitive group of species with respect to boric acid and sodium tetraborate.

46There are only screening data for fish for borate esters, specifically, only for tributylborate. These screening data showed no effects at 10.0 m g /L for 24 hours towards three species of fish. However, the purity of the tributylborate was not given. The only data for boranes are for tert-butylamine borane. These data are: fish 96-h LC50 = 13.0 m g /L, daphnid 96-h LC50 = 0.700 m g /L, green algal 7-d EC50 = 3.0 m g /L, and algal ChV = 0.300 m g /L. The only toxicity information for boron hydrides are for m amma ls. These data show that all boron hydrides are highly toxic and m o re toxic than borates. The m a jor environmental hazard concerns for this category are for chronic toxicity towards fish and toxicity towards green algae. Since there is no SARs for boron com pounds, hazard profiles are developed using the nearest analog(s).
Boundaries. Boron compounds m u st have water solubilities equal to or greater than 1.0 

### : g/L (ppb) and m o lecular weights generally need to be near or below 1000.
Environmental Fate. Certain borates are subject to hydrolysis under environmentally realistic conditions. General Testing Strategy. The f o llowing testing strategy will address aquatic toxicity concerns:
I. Release to Aquatic Ecosystem s : Tier 1a. If the hydrolysis rate for any m emb er of this class is predicted to be slow (t1⁄2 > 2 days) or if hydrolysis will result in one or m o re products which are expected to be just as toxic as the parent borate, then the fish and daphnid acute toxicity tests from the aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures. The acute toxicity tests for fish (40 CFR 797.1400 or OPPTS 850.1075) and daphnids (40 CFR 797.1300 or OPPTS 850.1010) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; measured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should equal the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. The algal toxicity testing (40 CFR 797.1050 or OPPTS 850.5400), should be done with static m e thods; measured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective

47concentrations at 24, 48, 72, and 96 hours; test m e di um with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nominal-basis equal to the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. If there is no significant risk from the PMN after the results of the environmental base set of tests have been integrated into the risk assessment, then no further testing is recom me nded. However, if there is a significant risk, then go to Tier 2. Tier 1b. If the hydrolysis rate for any m emb er of this class is predicted to be rapid (t1⁄2 < 2 days) and if hydrolysis will result in products which are expected to be significantly less toxic as the parent borate, then hydrolysis as a function of pH and tem p erature (40 CFR 796.3510 or OPPTS 835.2130) will be recomm e nded. If the resulting hydrolysis t1⁄2 is < 2 days, then this result will be integrated into a new risk assessment for the PMN. However, the resulting hydrolysis t1⁄2 > 2 days, then the environmental base set will be recom me nded. If there is no significant risk from the PMN after the results of the environmental base set of tests have been integrated into the risk assessment, then no further testing is recom me nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR 797.1600 or OPPTS 850.1400), with flow-through m e thods; measured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; and statistical analysis of effective concentrations at days 7, 14, 21, and 28. Daphnid chronic toxicity testing ( 40 CFR 797.1330 or OPPTS 850.1300), with flowthrough m e thods; measured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21. Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 or OPPT 835.3100 Modified Sturm Test 40 CFR 796.3260 or OPPT 835.3110 Closed Bottle Test 40 CFR 796.3200 or OPPT 835.3110 Modified OECD Screening Test 40 CFR 796.3240 or OPPT 835.3110 Modified MITI Test (I) 40 CFR 796.3220 or OPPT 835.3110 Modified AFNOR Test 40 CFR 796.3180 or OPPT 835.3110
II. Release to terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e.,

48the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial expos ures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay. July, 1991; revised August, 1997.

49Category: Cationic Dyes Environmental Toxicity
Definition. Any dye bearing one or m o re net permanent positive charges is considered to be a memb er of this class. A "typical" new chemical of concern is a water soluble monoazo dye with a single delocalized positive charge.
Haz a rd Concerns. Wa ter soluble cationic dyes are toxic to fish, daphnids, and algae. Poorly soluble dyes tend to be toxic only to algae. No relationship between structure and activity has been found for cationic dyes.
Boundaries. There are no established boundaries for cationic dyes. There is no m o lecular weight threshold - one dye with a m o lecular weight of 3,000 and bearing four positive charges was found to be toxic to fish. Testing. To adress environmental concerns, the base set of environmental toxicity tests (i.e., the fish acute toxicity test, the daphnid acute toxicity test and the green algal toxicity test) is recomme nded. These tests are to be done using the static m e thod and nominal concentrations. In addition, two additional fish acute toxicity tests are recomme nded with known amounts of humic acid added to the dilution water. This testing is necessary to measure the mitigating effects of dissolved organic carbon (DOC) on the t oxicity of the cationic dye. One test will be done with 20 m g humic acid/L in dilution and the second test will have 10 m g humic acid/L in dilution water. Total organic carbon (TOC) will be measured three times in each test and the TOC of the clean dilution water will also be measured at the beginning of the test. If DOC mitigates the environmental risk to water columnorganism s, then testing using natural sedim e nts and organism s known to ingest sedim e nt m a y be recomme nded. March, 1990

50Category: Cationic (quaternary ammonium) surfactants Environmental Toxicity
Definition. Any cationic surfactant is a m emb er of this category, for example:
CH 3 | CH 3 -N + -(CH 2 -) 15 -CH 3 Br ­ | CH 3 Haz a rd Concerns. Cationic surfactants are biocidal to a wide array of species in the environment. Toxicity increases exponentially with increasing carbon chain length up to 16 carbons and then decreases with increasing chain length. QSAR (quantitative structure-activity relationships) have been developed to predict toxicity.
Boundaries. Little toxicity is observed when the carbon chain length exceeds 22. Tight ion pairs will not be signif i cantly toxic. General Testing Strategy . To address ecotoxicity concerns, base set aquatic toxicity testing in algae, daphnids, and fish, plus humic acid testing in fish (20 m g /L humic acid in dilution water and 10 m g /L) is recomme nded. All testing uses static m e thod, nominal concentrations. March, 1990

51Category: Cobalt Environmental Toxicity This category includes but is not limited to inorganic and organic compounds of cobalt (Co), e.g., soluble cobalt cations, cobalt esters, and organocobalt compounds.
Haz a rd Concerns

. Most of the toxicity inform ation for inorganic cobalt compounds is for the soluble salts: chloride, nitrate, and sulfate. There are no known data for organoCo compounds, organic acid chelates with Co, or for Co esters. The best toxicity data for Co are listed below with predicted (P) and measured (M) toxicity values indicated and effective concentrations in m g Co/L (ppm): fish (FHM) 96-h LC 50 daphnid 48-h LC 50 daphnid 48-h LC 50 WQ 2° acute value green algal 7-d EC 50 RTELS 28-d LC 50 fish ChEC 20 fish Chronic Value (ChV) fish ACR daphnid ChEC 20 daphnid ChV daphnid ChV daphnid ACR WQ 2° chronic value algal ChV Abbreviations: = = = = = = = = = = = = = = = 48.0 M S,?,H130,Cl E86 1.32 M Cl B&S74 1.11 M S,N,H45,Cl B&C72 0.195 P S96 0.160 M S,? NO3,Cl,SO4 St81 0.470 M SR12h,?,H104,NO3 B78 0.810 M S96 0.290 M S96 170.0 P 0.004 M S96 0.010 M S,N,H45,Cl B&C72 0.005 M S96 110.0 P B&C72 0.003 P S96 0.040 P EC50÷ChV=4

ACR = acute-to-chronic ratio; Ch = chronic; ChV = chronic value; CC = concern concentration; ELS = early life stage; FHM = fathead minnow; H = hardness as CaCO 3 ; N = nominal concentrations; ? = m e thod unknown; RT = rainbow trout; S = static m e thod; SR12h = static renewal m e thod with renewals every 12 hours; and

52WQ = water quality value.
Predictions were based on SARs for inorganic Co compounds; pH 7; hardness <180.0 m g /L as CaCO 3 ; 100% active ingredients; m ean measured concentrations of Co; and total organic carbon (TOC) <2.0 m g /L; Environmental concerns for Co compounds:

m oderate concern for acute toxicity to fish; m oderate concern for acute toxicity to daphnids; high concern for toxicity to green algae; m oderate concern for chronic toxicity to fish; high concern for chronic toxicity to daphnids; high concern for toxicity to green algae; assessment factor (AsF) = 10.0 COC for fish = 0.030 COC for daphnids = 0.001 COC for green algae = 0.004 The aquatic toxicity for the chelates and esters of Co are expected to be less than predicted using toxicity data based on the soluble ion and with a MW adjustm e nt. The aquatic toxicity for organoCo could be higher than predicted using toxicity data based on the soluble ion and with a MW adjustm e nt because the organic portion could enhance uptake in aquatic organisms. It is assum e d that (1) the MWs of organoCo compounds would have to be less than 1000 daltons and (2) the log K ow of any organoCo would have to be less than 8.0 for toxicity to aquatic organisms to occur. It is also assum e d that the aquatic toxicity of organoCo compounds will increase with increasing K ow when the log K ow <8.0. The m a jor environmental toxicity concerns for this category are for chronic toxicity towards daphnids and toxicity towards green algae. The acute-to-chronic ratios of Co towards fish and daphnids are both greater than 100. The SAR m e thod for Co compounds is the nearest analog(s) m e thod.
Boundaries. Cobalt compounds m u st have water solubilities equal to or greater than 1.0 

### : g/L (ppb) and m o lecular weights generally need to be near or below 1000. The log K compounds has to be <8.0. ow of organoCo

53Fate: General Testing Strategy : I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity test s for fish (OPPTS 850.1075) and daphnids (OPPTS 850.1010) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; ideally, m e an measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; and solvent can be used to assist the test chemical to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the test chemical beyond its aqueous solubility limit. Stock solutions in water should be adjusted to pH near 7.0. The algal toxicity testing (OPPTS 850.5400), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; ideally, mean m easured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; and solvent can be used to assist the test chemical to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the test chemical beyond its aqueous solubility limit. Stock solutions in water should be adjusted to pH near 7.0. If there is no significant risk from the test chemical after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recom me nded. However, if there is a significant risk, then go to Tier 2. Tier 2. For organoCo compounds, or chelates or esters of Co, aerobic biodegradability according to either of the following test guidelines: Ready Biodegradability OPPTS 835.3110 Sealed Vessel CO2 Production Test OPPTS 835.3120 If there is no significant risk from the test chemical after the results of biodegradation testing have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 3. Tier 3. Fish chronic toxicity testing, i.e., fish early life stage (ELS) toxicity testing (OPPTS 850.1400), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrati ons at days 7, 14, 21, and 28; me asured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; solvent can be used to assist the test chemical to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance

54the water solubility of the test chemical beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because the 7-d ELS toxicity test m a y underestimate chronic toxicity measured by the 28-d ELS toxicity test when the Chronic Values are com p ared. Stock solutions in water should be adjusted to pH near 7.0. Daphnid chronic toxicity testing (O PPTS 850.1300), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; solvent can be used to assist the test chemical to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the test chemical beyond its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test because the fish 7-d ELS toxicity test m a y underestimat e chronic toxicity measured by the fish 28-d ELS toxicity test when the chronic values are com p ared.
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil mi crobial comm unity bioassay.
References. B78 = Birge. 1978. USDOE Tech Info B&C72 = Biesinger&Christensen. 1972. J Fish Res Brd Can 29:1691 B&S74 = Baudouin&Scoppa. 1974. Bull Environ Contam Toxicol 12:745 E86 = Ewell etal. 1986. Environ Toxicol Chem 5:831 S96 = Suter, GW. 1996. Environ Toxicol Chem 15:1234 St81 = Stokes. 1981. J Plant Nutrit 3:667 September, 1996.

55Category: Diazoniums Environmental Toxicity This category includes only aromatic diazoniums (N 

### / N + ). Aliphatic diazoniums are very explosive and are only used as synthesizing agents

. Aromatic diazoniums are used as fungicides on seeds and in soil, e.g., Fenam i nosulf. It is known that diazoniums need to be absorbed to be toxic. Test data submitted to the Agency in the New Chemicals Program showed that diazo compounds with a number average m o lecular weight (MWn ) > 1000 have no effects at saturation to fish in the acute toxicity test. Therefore, compounds with MWn's > 1000 will be excluded f r om this category regardless of water solubility. In the NEAT state, diazoniums are solids, i.e., salts, and are m o st are soluble in aqueous m e dia. Acute toxicity for diazoniums is assum e d to be limited by the octanol/water partition coef fi cient (K ow ; with a m i ssing fragm e nt for N 

### / N + ) and MW

. Above a log K ow value of => 8.0 and/or MW = 1000, diazoniums are not expected to be toxic at saturation during 96-h exposures. Diazoniums are expected to be similar to anilines with respect to their K ow cutof f value f o r acute toxicity. This assum e s that the m i ssing fragment for N 

### / N + = -1.0. The acute toxicity of anilines dim i nishes at about a log K ow = 7.0 (Veith and Broderius 1987). There are no known K ow limits f o r chronic toxicity at this time, but it m a y not be m u ch above a log K ow = 10.0 for diazoniums. Future testing will determine this K ow limit.
Haz a rd Concerns. The acute toxicity for diazoniums has been determ ined through SAR Analysis: log fish 96-h LC 50 (millimoles/L) = -2.456 - 0.331 log K ow based on a log K ow for the diazonium using CLOGP Ver. 3.3 with a m i ssing fragm e nt for N 

### / N + , N = 3, and R2 = 0.98. Acute toxicity values are assum e d to be valid through log K ow = 8.0. Daphnids are assum e d to have similar sensitivity to fish, but green algae are expected to be m o re sensitive based on the use of diazoniums as fungicides.
Fate : Diazonium fungicides, e.g., Fenam i nosulf, ar e sensitive to light but is stabilized with Na sulphite. Fenam i nosulf is stable in alkaline m e dia. Diazoniums are also used in photography, e.g., diazo reproduction paper and film

. Therefor e, diazoniums are expected to be subject to rapid direct and indirect photolysis under environmentally realistic conditions. Diazoniums are also expected to slowly hydrolyze to phenols.
Boundaries. : There are no known lower boundaries. The upper boundaries will be based on K ow and MW

. Acute toxicity expected with log K ow < 8.0 with a m i ssing fragm e nt for N 

### / N + .; no effects at saturation during 96-h exposures when log K ow >= 8.0. Chronic toxicity has no known upper bound for log K ow , but it is probably near 10.0 with a m i ssing fragm e nt for N 

### / N +

. MWmu st be < 1000. The environmental base set of tests will be requested for aquatic releases and the terrestrial base set of tests will be recomme nded for terrestrial exposures. Wh en the log K ow is >= 10.0, chronic toxicity testing with fish and daphnids will be recomme nded.

56General Testing Strategy . I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. Since diazoniums compounds are photosensitive to uv light, it is best to avoid the use of fluorescent lights in toxicity tests. If they are used, then glass filters should be used. The acute toxicity tests for fish (CFR §797.1400) and daphnids (CFR §797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. The algal toxicity testing (CFR §797.1050), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nominal-basis cannot exceed the PMN's aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. If there is no significant risk from the PMN after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Direct and Indirect Photolysis Screening Test (40 CFR 796.3765). If t1⁄2 < 2 days, go to Tier 3; if t1⁄2 > 2 days, go to Tier 4. Tier 3a. If t1⁄2 < 2 days and photolysis products are known and/or identified, then assess photolysis products for environmental hazards. Tier 3b. If t1⁄2 < 2 days and photolysis products are not known and/or identifiable, then prepare a stock solution of PMN using the sta ndard humic-containing solution described in the direct and indirect photolysis screening te st [40.796.3765 (b)(2) and (c)(2)], expose to sunlight for at least 6 half-lives (t1⁄2), and test photolysis products for toxicity with m o st sensitive species fr om environmental base set. For example, the m o st sensitive species f r om the environmental base set has an EC50 value = 2.0 m g PMN/L (based on 100% active ingredients [AI]), therefore, prepare a 5.0 m g PMN per liter stock solution based on 100% AI using the standard humiccontaining solution. This stock solution is exposed to sunlight for at least 6 half-lives to ensure that all of the PMN has been photolyzed, and then this stock solution is used to retest the m o st sensitive aquatic species to determine if the photolysis products of the PMN are m o re or less

57toxic that the PMN. Tier 4. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (CFR §797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the PMN; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because Van Leeuwen et al (1990) have demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28- d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen); Daphnid chronic toxicity testing (C FR §797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean m easured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; the highest treatment concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test because Van Leeuwen et al (1990) have demons trated that the fish 7-d ELS toxicity test underestim ated the chronic toxicity of anilines m easured by the fish 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test, the avian acute oral toxicity test, and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, avian reproduction toxicity test, and the soil m i crobial comm unity bioassay.

58References. Van Leeuwen CJ, Adema DMM, and Hermens J. 1990. Quantitative structure-activity relationships for fish early life stag e toxicity. Aquatic Toxicology 16:321-334. Veith GD and Broderius SJ. 1987. Structure-toxi city relationships for industrial chemicals causing type (II) narcosis syndrome. In Kaiser KLE (ed), QSAR In Environmental Toxicology - II, p 385-391. Reidel Publishing Com p any.

Novem b er, 1991

59Category: Dichlorobenzidine-based Pigments Hum a n Health Environmental Toxicity
Other Names: Diarylide Pigments, DCB Pigments, Pigment Yellows
Definition: Any diazo pigment containing the substructure, dichlorobenzidine, and coupled with acetoacetanilide.

Haz a rd Concerns. There are oncogenicity/mutagenicity concerns for dichlorobenzidine-based pigments based on the potential release of 3,3'-dichlorobenzidine and on the presence of residual (unbound) dichlorobenzidine. DCB is a known animal carcinogen and a suspect human carcinogen. In addition, DCB is known to bioconcentrate in the tissues of aquatic organisms.
Boundaries. Concern for the intact pigment is restricted to uses at tem p eratures exceeding 200 o C. Data submitted to the Agency under TSCA section 8(e) show that DCB pigments break down to release DCB as a vapor from colored polymers when heated to extrusion tem p eratures (> 200 o C) and, from sheetm e tal coatings during curing. Though little information exists on the biodegradation of pigments in sedim e nts, data on other low water soluble colorants, indicate that biodegradation m a y occur over a period of months, possibly resulting in the release of DCB. General Testing Strategy. EPA's New Chemicals Program considers the follo wing tests to be appropriate to address the potential for DCB pigments to pose a significant risk to health or the environment: 1. Monitoring data to detect the presence of DCB under actual conditions of use; tem p erature, dwell time, % pigm ent in polymer or coating, and type of polymer or coating. 2. If there are releases to water, an anaerobic biodegradation assay.

60References: Appleton HT, Sikka HC. 1980. Accum u lation, elimination, and m e tabolism of 3,3'

- dichlorobenzidine in the bluegill sunfish. Environ Sci Technol 14:50-54. Pliss GB. 1963. On som e regular relationship between carcinogenicity of aminobiphenyl derivatives and the structure of the substance. Acta Unio Int Cancrum 19:499-501. Stula EF, Sherm a n H, Reinhardt CF. 1975. Expe rim e ntal neoplasia in rats from oral adm i nistration of 3,3'-dichlorobenzidine, 4,4'-methylene-bis(2-chloroaniline), and 4,4'

- me thylene-bis(2-m e thylaniline). Toxicol Appl Pharmacol 32:159-176. Stula EF, Barnes JR, Sherm a n H. 1978. Liver and urinary bladder tum o rs in dogs from 3,3- dichlorobenzidine. 1978. J Environ Pathol Toxicol 1:475-490. TSCA Section 8(e) Docum e nts: 8EHQ-0490-0962 INIT 8EHQ-0590-0962 SUPPL 8EHQ-0690-0962 FLW P 8EHQ-0790-0962 SUPPL 8EHQ-0890-0962 SUPPL

March, 1994

61Category: Dithiocarbamates Environmental Toxicity This category includes N,N-dialkyldithiocarbam a tes (DDC); ethylenebisdithiocarbam a tes (BDC); and their m e tal salts which include but are not limited to zinc, sodium, iron, m a nganese, copper, lead, m e rcury, silver and selenium

. The alkyl groups of the DDCs generally include, me thyl through butyl, but m a y be larger. This cat egory also includes the degradation products of DDC and BDC which m a y include disulfide m o ieties, sulfide m o ieties, thiourea m o ieties, urea mo ieties, polymeric sulfide m o ieties, dithizaole-3-thiones, cyclic thioureas and cyclic ureas as indicated in the generic environmental hazard assessment.

Haz a rd Concerns: Many m emb ers of this category are comme rcial insecticides, fungicides, disinfectants, rodenticides, antioxidants, slimicides, algalicides, bactericides and heavy m e tal chelators. Their mode of toxic action apparently results from interference with m e tallo-enzymes in living cells; the toxicity has been attributed to either DDCs and BDCs or their degradation products. All of the known dithiocarbam a tes are acutely toxic to fish, algae and bacteria at < 10 mg /L, and to aquatic invertebrates at < 1 m g /L. Chronic toxicity to fish and aquatic invertebrates ranges from 0.001 to 2 m g /L and 0.011 to 0.111 m g /L, respectively. In general, the SARs for the dithiocarbam a tes and their degradation products are sigmoidal with acute and chronic toxicity increasing with increasing Kow. The sigmoidal relationship between Kow and toxicity of the dithiocarbam a tes is very poor statistically. Consequently, toxicity predictions will be m a de using either the closest analog or averaging data for the two closest analogs which bracket the dithiocarbam a te under question. The SAR for the degradation products is m u ch m o re robust and a series of SARs will be used to predict acute toxicity of degradation products toward fish, daphnids and Photobacterim phosphoreum ; and chronic toxicity toward fish, daphnids and green algae.
Boundaries: There are no known lower boundaries. The upper boundaries are based on K and MW . Wh en the log Kow value is < 5 m g /L, the environmental base set of tests will be requested f o r aquatic releases and the terrestrial base set of tests will be recom me nded f or ow

62terrestrial exposures. Wh en the log K ow is between 5 and < 19, only chronic toxicity testing will be recomme nded. Wh en the log K ow is > 19 (CLOGP), no testing will be requested because no toxic ef f ects at saturation will be expected. Generally, m emb ers of this category will have MW s of less than 1000. General Testing Strategy Tier 1. The acute aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures and the terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm acute toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Tier 2. If acute toxicity testing indicates a si gnificant risk, then chronic toxicity with fish and aquatic invertebrates will be recomme nded as well as aerobic biodegradation testing. Aerobic biodegradability can be determined using one of the following test guidelines, listed in approxim a te order of preference: Aerobic aquatic biodegradation Modified Sturm test Closed bottle test Modified OECD screening test Modified MITI test (I) Modified AFNOR test
August 1989; revised Novem b er 1995 40 CFR 796.3100 40 CFR 796.3260 40 CFR 796.3200 40 CFR 796.3240 40 CFR 796.3220 40 CFR 796.3180

63Category: Epoxides Hum a n Health Environmental Toxicity Definition. Any m o lecular structure containing one or m o re epoxy groups is considered to be a memb er of the category:
O / \ -C---C­

| |
Haz a rd Concerns. Health concerns for epoxides are for cancer and reproductive effects based on data for several analogous chemicals. There is greater concern for primary epoxides,
O / \ -C---CH

H H than for epoxides with substitutions on both of the epoxy carbons. Environmental toxicity is a function of the octanol-water partition coefficien t. Compounds with log P's >5 act as neutral organics producing sim p le narcosis, but at lower log P' s, epoxides display toxicity greater than that predicted f o r sim p le narcotics. A QSAR (quantitative structure-activity relationship) to predict the environmental toxicity of epoxides is under development.
Boundaries. Structures with epoxy equivalent weights of > 1,000 are presumed not to pose a hazard under any conditions. Concerns are confined to those species with m o lecular weights <1,000. Health concerns are restricted to species with m o lecular weights <500 if exposure is limited to the dermal route. Testing. To address health concerns the following tests are usually recomme nded for m emb ers of this class: (1) a lifetime cancer bioassay by the expected route of exposure, and (2) a 90-day subchronic with attention to pathology of the reproductive organs. To address ecotoxicity concerns, base set acute aquatic toxicity testing (algae: static m e thod, daphnid and fish: flowthrough m e thod, all measured concentrations). September, 1988

64Category: Esters Environmental Toxicity This category includes all esters, polyesters, vinyl esters, allylic esters, propargylic esters, aliphatic esters, aromatic esters, carboxylic acid esters, and sulfonate esters. These compounds need to be absorbed to be toxic, therefore, compounds with MWs > 1000 will be excluded from this category. Acute toxicity for esters which are liquids at room tem p erature is known to be limited by the octanol/water partition coef fi cient (K ow ). Above a log K ow value of => 5.0, esters show no effects at saturation during 96-h exposures (Veith et al 1984). Esters which are solids at room tem p erature m a y show no toxicity at saturation at lower K ow values depending on the me lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no acute toxicity will be observed at saturation. Fo r solids, the no-effects-at-saturation point has to be determined on a case-by-case basis. The K ow limit f o r chronic toxicity is set at a log K ow = 8 fo r liquid esters. For solid esters, chronic toxicity testing will determine this K ow limit.
Haz a rd Concerns. The toxicity for sim p le esters has been determ ined through SAR Analysis (Clem e nts 1988). Esters are known to be m o re toxic than neutral organic chemicals, and this excess toxicity decreases with increasing K ow . The toxicity for vinyl esters, allylic esters, and propargylic esters is expected to be greater than for sim p le esters. Again, the additional excess toxicity of these vinyl esters, allylic esters, and propargylic esters is expected to decrease with increasing K ow . Mem b ers of this category exhibit toxicity rangi ng from low toxicity (i.e., > 100 m g /L) to high

ow , MW, and m e lting point. toxicity (i.e., < 1 m g /L) depending on their K
Boundaries

. There are no known lower boundaries. The upper boundaries will be based on K ow and MW

. Acute toxicity is expected when log K ow < 5.0; no effects at saturation during 96-h exposures when log K ow > 5.0. The upper boundary for chronic toxicity is 8.0. MW will be < 1000. The environmental base set of tests will be requested for aquatic releases and the terrestrial base set of tests will be recomme nded for terrestrial exposures. Wh en the log K ow is > 5.0, chronic toxicity testing with fish and daphnids will be recomme nded.
Fate : Esters are subject to both abiotic and biotic hydrolysis, i.e., ester hydrolysis, and aerobic biodegradation. Aerobic biodegradation is expected to be the dominant route of transform a tion in the environment. General Testing Strategy

. I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity tests for fish (40 CFR §797.1400) and daphnids (40 CFR §797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit; and solvent can be used to assist the ester to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the ester
65beyond its aqueous solubility limit. The algal toxicity test (40 CFR §797.1050) should be done with the static m e thod; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nom inal-basis should not exceed the aqueous solubility limit of the ester; and solvent can be used to assist the ester to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the ester beyond its aqueous solubility limit. If there is no significant risk from the ester after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180 If there is no significant risk from the ester after the results of the aerobic biodegradation testing have been integrated into the risk assessm ent, then no further testing is recomm e nded. However, if there is a significant risk, then go to Tier 3. Tier 3. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR §797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested chemical; solvent can be used to assist the ester to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the ester beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because Van Leeuwen et al (1990) ha ve demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). Both anilines and esters are m o re toxic than predicted based on narcosis alone, i.e., both esters and anilines have excess toxicity due to a m o re specific mode(s) of toxic action. A seven day exposure m a y not allow enough time for this excess toxicity to be expressed either because of not enough exposure and/or not enough time for m e tabolic activation. Daphnid chronic toxicity testing ( 40 CFR §797.1330), with flow-through m e thods;
66m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the ester; solvent can be used to assist the ester to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the ester above its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test (Van Leeuwen et al 1990).
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test, the avian acute oral toxicity test, and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, the avian reproductive toxicity test, and the soil m i crobial comm unity bioassay.
References. Clements, RG (editor). 1988. Estimating toxicity of industrial chemicals to aquatic organism s using structure-activity relationships. EP A-560-6-88-001. Wa shington, DC: Environmental Effects Branch, Health and Environmental Revi ew Division, Office of Toxic Substances (TS796), United States Environmental Protection Agency. Available from the National Technical Information Service, Springfield, VA 22161, PB89-117592. Van Leeuwen CJ, Adema DMM, and Hermens J. 1990. Quantitative structure-activity relationships for fish early life stag e toxicity. Aquatic Toxicology 16:321-334. Veith GD, DeFoe D, and Knuth M. 1984. Structur e-activity relationships for screening organic chemicals for potential ecotoxicity effect s. Drug Metabolism Reviews 15(7):1295-1003.
Novem b er, 1991

67Category: Ethylene Glycol Ethers Hum a n Health
Definition. The ethylene glycol ether category is defined as follows: R-(OCH 2 CH 2 ) n -OR' n = 1, 2, or 3 R = alkyl C 7 or less or phenyl or alkyl substituted phenyl R' = H or alkyl C 7 or less or any group that can be chemically or me tabolically removed to yield a glycol ether
Haz a rd Concerns. Short-chain ethylene glycol ethers are absorbed by all routes of exposure and have caused irritation of skin, eyes, and m u cous m e mb ranes; hem o lysis, bone-marrow dam a ge, and leukopenia of both lymphocytes and granulocytes; direct and indirect kidney dam a ge; liver dam a ge, immunotoxicity, and central nervous system (CNS) depression. Shortchain ethylene glycol ethers are also developmental and reproductive toxicants. 2- Phenoxyethanol is known to cause hem o lysis and eye irritation.
Boundaries. There is evidence that developmental toxicity is reduced going from the m e thyl to the butyl ether, and that it is reduced going from the ethylene glycol to the triethylene glycol. However, there is still a concern f o r m a ternal toxicity as ref l ected in developmental and subchronic toxicity studies. The systemic toxic ity of longer-chain glycol ethers and alkylphenyl glycol ethers is uncertain because data are not available. The alkyl chain length of C 7 or less was chosen as a boundary for short-chain ethylene glycol ethers based on the available data. General Testing Strategy The New Chemicals Program considers the following tests to be the m o st appropriate for ethylene glycol ethers with sufficient exposure to potentially pose an unreasonable risk: Tier 1 - Com b ined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screen Test (OECD Guideline 422). If signs of hem a turia are seen red and white blood cell counts should be taken 2 days later except for fem a le animals during pregnancy and lactation. Tier 2 - The need for further testing would be determined by the results of Tier 1. This could include any of the following tests. Prenatal Developmental Toxicity via the m o st appropriate route (40 CFR 799.9370) 2-Generation Reproduction Study via the mo st appropriate route (40 CFR 799.9380) 90-Day Subchronic Study via the m o st appropriate route (40 CFR 799.9346 - inhalation route; 870.3250 - dermal route; 870.3150 - oral route)

68Imm unotoxicity Study via the m o st appropriate route (OPPTS 870.7800) June 1992, revised December 1997

69Category: Hydrazines and Related Compounds Hum a n Health Environmental Toxicity

Definition: Any structure containing one or m o re of the following groups is considered to be a m em b er of the category:

Haz a rd Concerns: Concerns for carcinogenicity and chronic effects to liver, kidney, and blood are based on data for a number of hydrazines and related chemicals. In humans, hydrazine, itself, m a y affect the central nervous system, liver, and kidneys. The toxic effects of hydrazine exposure to humans m a y range from m ild skin and eye irritation, and skin sensitization, to severe irritation and burns, pulmonary edema, CNS depression, as well as liver and kidney dam a ge, which can lead to death. Hydrazine m a y also present a serious hazard to plant life and aquatic organisms. Ecotoxicity concerns are based on structure activity relationships (SAR) using data for a number of hydrazines and hydrazides. Hydrazine itself (N 2 H 4 ), is known to be acutely toxic to aquatic organisms at low levels, algae at < 100 ppb, 200 ppb for fish, and 30 ppb for daphnids.

Boundaries: There are no established boundaries for this category. The "typical" new chemical m emb er of the category is a discrete (class I) chemical with a m o lecular weight <500. There is a greater concern for chemicals with few substitutions on the functional group than for

70those with m u ltiple substitutions.
General Testing Strategy EPA considers the following tests to be appropriate to address health and ecotoxicity concerns: 1. Lifetime cancer bioassay by the expected route of exposure in two species of rodents (40 CFR 798.3300). 2. 90-Day subchronic in one species of rodent by the expected route of exposure to assess effects to the liver, kidney, and blood (40 CFR 798.2650). 3. Base-set ecotoxicity testing to include fish (40 CFR 797.1400) using the flow-through me thod, daphnids (40 CFR 797.1300) using the flow-through m e thod and algae (40 CFR 797.1050) using the static m e thod, all measured concentrations. Results of the acute ecotoxicity testing m a y trigger chronic fish (40 CFR 797.1600) and daphnid (40 CFR 797.1350) testing.
4. Environmental fate testing including, as appropriate, m e lting point (40 CFR 796.1300) or boiling point (40 CFR 796.1220), water solubility (40 CFR 796.1840 or 796.1860), log K ow (40 CFR 796.1550, 796.1570 or 796.1720), vapor pressure (40 CFR 796.1950) and hydrolysis (40 CFR 796.3500). For aromatic hydrazines and related compounds, the following additional testing is recomme nded; direct and indi rect photolysis (40 CFR 796.3765), and aerobic biodegradation. Aerobic biodegradability can be determined using one of the following test guidelines, listed in approxim a te order of preference: Aerobic aquatic biodegradation Modified Sturm test Closed bottle test Modified OECD screening test Modified MITI test (I) Modified AFNOR test

References. 40 CFR 796.3100 40 CFR 796.3260 40 CFR 796.3200 40 CFR 796.3240 40 CFR 796.3220 40 CFR 796.3180

1. Bhide, S.V., R.A. D'Souza, M.M. Sawai, & K.J. Ranadive (1976). International Journal of Cancer 18: 530. 2. Biancifiori, C (1970). Journal of the National Cancer Institute 44: 943.

713. Biancifiori, C (1971). Lav. 1 st Anat. Istol. Pat., Univ. Studi Perugia 31: 5.
4. Biancifiori, C., E. Bucciarelli, D.B. Clayson, & F.E. Santilli (1964). British Journal of Cancer 18: 543.
5. Hydrazine-RM2 Exit Docum e nt. OPPT Office Director' s Meeting, Monday, Decem b er 13, 1993. 6. Juhasz, J., J. Balo, & B. Szende (1966). Nature (London) 210: 1377. 7. Juhasz, J., J. Balo, & B. Szende (1967). Z. Krebsforsch 70: 150. 8. Toth, B. (1969). Journal of the National Cancer Institute 42: 469. 9. Toth, B. (1972). International Journal of Cancer 9: 109. September, 1988; revised June, 1994, revised October 1995.

72Category: Hindered Amines Hum a n Health
Definition. The category is at present not well de fined. A "typical" new chemical hindered amine of concern has two or m o re hindered amine functional groups, usually the 2,2,6,6- tetramethyl-4-piperidinyl group, and is used as a UV light stabilizer.

Haz a rd Concerns. Health concerns f o r the category are based on data submitted to the Agency under §8(e) of TSCA for Tinuvin 144 and Chimassorb 944. The data indicate that these hindered amines, and presumably hindered amines similar in structure, are toxic to the im m une system, liver, blood, the m a le reproductive system, and the G.I. tract.
Boundaries. The boundaries of the category are not well defined. Tinuvin 144 has a m o lecular weight of 685, whereas Chimassorb 944 is a polym er with a number average m o lecular weight well in excess of 1,000. As a consequence, there is at present no m o lecular weight cutoff for hindered amines of concern to the new chemical program

. It is assum e d that there is little or no dermal absorption of problematic hindered amines because of their high m o lecular weights. Consequently, hindered am ines in the new chemical program are only of concern if there is signifi cant inhalation exposure associated with their ma nufacture, processing, or use. General Testing Strategy For hindered amines found to pose a potentially unreasonable risk, a 90-day oral subchronic test in rats is the recomme nded test. We have requested that emphasis be placed on hem a tology, the imm une system, and on the m a le reproductive system

. June 1990; revised March 1995

73Category: Imides Environmental Toxicity This category includes all imides and m a leimides. Substitutions m a y be aliphatic, aromatic, and/or halogens. The mode of toxic action of imides is unknown, but halogenated imides are used as m i crobial pesticides, specifically, fungicides, bactericides, slimicides, and algicides. It is assum e d that these compounds need to be absorbed to be toxic, therefore, compounds with MW s > 1000 will be excluded from this category. Acute toxicity for imides which are liquids at room tem p erature is assum e d to be limited by the octanol/water partition coef fi cient (K ow ), and the limiting K ow value for acute toxicity is assum e d to be about 5.0. The limiting value for chronic toxicity is assum e d to be about 8.0. Imides which are solids at room tem p erature m a y show no toxicity at saturation at log K ow values < 5.0 depending on the m e lting point, i.e., the higher the me lting point at a given K ow , the greater the likelihood that no toxicity will be observed at saturation. For solids, the no-effects-at-saturation determination has to be m a de on a case-bycase basis.
Haz a rd Concerns. The acute toxicity f o r im ides and m a leimides towards f i sh has been determined through SAR Analysis by EPA. The SAR for acute toxicity to fish is defined by the following regression equation: log 96-h LC50 = 1.256 - 0.76 log K ow where the LC50 is in milliMoles per Liter (mM/L), N = 4, and R2 = 0.98. The acute toxicity of imides towards daphnids is expected to be similar to that of fish, but their toxicity towards green algae is expected to be greater because of their use as m i crobial pesticides. Polyimides m a y be m o re toxic than predicted using this SAR. The toxicity of imides towards aquatic organism s can range from low (i.e., > 100.0 m g /L) to

ow and MW

. The higher the K lower the MW, the higher the toxicity (or the lower the EC50 value). high toxicity (i.e., < 1.0 m g /L) depending on their K ow and the

Boundaries. : There are no known lower log K ow and MW boundaries. The upper boundaries fo r acute toxicity will be set at a log K ow < 5.0; chronic toxicity limits will be set at a log K ow < 8.0. MW will be < 1000 for stable compounds. The environmental base set of tests will be requested f o r aquatic releases and the terrestrial base set of tests will be recom me nded f or terrestrial exposures. General Testing Strategy. The aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures. The acute toxicity tests for fish (40 CFR 797.1400) and daphnids (40 CFR 797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis

74should equal the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility. The algal toxicity testing (40 CFR 797.1050), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nom inal-basis equal to the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility. Fish chronic toxicity testing, i.e., fish early life stage (ELS) toxicity testing (40 CFR 797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because Van Leeuwen et al (1990) have demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen); Daphnid chronic toxicity testing ( 40 CFR 797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean m easured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; the highest treatment concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test because Van Leeuwen et al (1990) have demonstrated that the fish 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the fish 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test [40 CFR 797.2800], the earthworm acute toxicity test [40 CFR 795.150], and the soil m i crobial comm unity bioassay [40 CFR 795.3700]) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organism s include: the plant whole life cycle test [40 CFR 797.2830], the plant uptake test [40 CFR 797.2850], and the soil m i crobial comm unity bioassay.

75References. Van Leeuwen CJ, Adema DMM, and Hermens J. 1990. Quantitative structure-activity relationships for fish early life stag e toxicity. Aquatic Toxicology 16:321-334. April, 1991

76Category: Diisocyanates Hum a n Health
Definition. Any m o lecular structure containing two or m o re isocyanate groups is considered to be a m emb er of the category for new chemical purposes:
R-(N=C=O) > 2

Mem b ers of the class include new isocyanate monomers as well as new oligomers, polymers, prepolymers, or reaction products of existing isocyanate monomers. Most new chemical diisocyanates of concern are polymers or oligomers containing well-known diisocyanate monomers such as toluene diisocyanate (TDI) or 4,4'-methylenediphenyl diisocyanate (MDI).
Haz a rd Concerns. Diisocyanates are of concern for potential dermal and respiratory sensitization, and for pulm onary toxicity. Ba sed on conflicting animal and human data for respiratory sensitization, the Agency has determined that there is presently not a reliable animal m odel for testing diisocyanates for potential respiratory sensitization. At this time, it is assum ed that all diisocyanates m a y be potential human respiratory sensitizers.
Most m emb ers of the diisocyanate category have not been tested for carcinogenic potential. Though the arom atic diisocyanates [MDI, TDI, dianisidine diisocyanate (DADI)] tested positive and one aliphatic diisocyanate [ h examethylene diisocyanate (HDI)] tested negative in one species, it is premature to m a ke any generalizations about the carcinogenic potential of aromatic versus aliphatic diisocyanates.
Boundaries. Structures with an isocyanate equivalent weight of > 5,000 are presumed not to pose a hazard under any conditions. Typically, concerns are confined to those species with mo lecular weights <1,000. Frequently, new chemical isocyanates are m a nufactured with a significant excess of isocyanate monomer. Under these circumstances, the excess monomer is usually regarded as mo re hazardous than the "new" chemical component, and these PMN substances are ordinarily not regulated under §5 of TSCA. For the purposes of risk assessment within the New Chemicals Program, a PMN substance is considered "existing" if m o re than 50% of the free isocyanate groups in the PMN substance (new chemical component + existing chemical monomer) reside on unreacted monomer(s). This does not relieve a Com p any, however, of any obligations to submit a PMN for the new chemical isocyanate if indeed it is not listed on the TSCA Inventory. General Testing Strategy . T he following testing is recomme nded to address the potential for pulmonary toxicity and dermal sensitization.

1. Dermal sensitization (OPPTS 870.2600).

772. 90-day Subchronic inhalation toxi city test in rodents (OPPTS 870.3465). In addition, appropriate hazard comm unication needs to be developed and implemented. Health and Safety Information. The following information provides guidance in developing hazard comm unication and protective measures language to accom p any new diisocyanate chemicals and form ulations. It is based on the Agency’s current understanding of the hazards associated with diisocyanates and the m o st effective means to limit exposure. Warnings

. Exposure to diisocyanates m a y cause the following human health effects: skin irritation and allergic reactions, respiratory irritation, respiratory sensitization, and lung toxicity; som e diisocyanates also m a y cause cancer. The likelihood that these effects will occur depends on a number of factors; among them, the level of exposure, frequency of exposure, part of the body exposed, and sensitivity of the exposed individual. Sym p tom s of allergic reaction and respiratory sensitization include rashes, cough, shortness of breath, asthm a , chest tightness and other breathing dif f i culties. There is uncertainty as to the m echanism by which sensitization occurs. In sensitized individuals, exposure to even small amounts of diisocyanates (below governm e nt-recomme nded workplace exposure levels) m ay cause allergic respiratory reactions like asthm aand severe breathing dif fi culties. It is especially important to note that contact with skin m a y lead to respiratory sensitization or cause other allergic reactions

. In som e cases, the effects of diisocyanate exposure m a y be imme diate and life-threatening; in others, the effects m a y be delayed and occur hours after the exposure has ended. Repeat or prolonged exposure to diisocyanates m a y also cause irritation to eyes, skin, respiratory tract and lungs, as well as adverse chronic lung effects, like decreased lung capacity and function. Individuals experiencing shortne ss of breath, tightness in the chest or other problems breathing should seek im me diate m e dical attention.
Protective Measures. In workplaces where individuals handle diisocyanates or coatings or other formulations that contain them, an industrial hygiene and safety program should be operative. Important components of this program include: hazard comm unication and training on safe handling practices; use of efficient and well-m a intained application equipment, engineering controls and personal protective equipment; housekeeping procedures including spill prevention and cleanup practices; and, if feasible, means to measure airborne levels of polyisocyanates and diisocyanates. During spray applications, workers should take precautions to avoid breathing vapors, m i sts or aerosols. Inhalation exposures should be limited to <0.05 m g /m 3 as an 8-hour time-weighted

78average (TW A ) for com b ined polyisocyanates and diisocyanates. 1 Engineering controls should serve as the first, m o st effective means of reducing airborne polyisocyanate and diisocyanate concentrations; an appropriate NIOSH/MSHA-approved respirator should be used as a secondary tool to lower exposures. Curren tly, downdraft spray booths and high-volume lowpressure (HVLP) spray guns appear to offer th e m o st efficient technology to reduce inhalation exposures; a m a intenance program should always be used to ensure optimal operating efficiencies. To limit dermal contact, individuals should wear impermeable gloves, protective clothing and goggles or glasses with side shields.

May 1990, revised July 1993, February 1995, and February, 1997

1 0.05 m g /m 3 or 0.005 ppm TWA is the American Conference of Governm e nt Industrial Hygienists (ACGIH) Threshold Limit Value (TLV ) for each hexam e thylene diisocyanate (HMDI), toluene-2,4-diisocyanate (TDI), and m e thylene bi sphenyl isocyanate (MDI). Also, OSHA has set 0.02 ppm as exposure ceilings for both TDI and MDI. 79Category: 

### $ -Naphthylamines, Sulfonated Hum a n Health
Definition: Any new chemical whose structure is consistent with the following general structure is considered to be a m emb er of the category of monosulfonated 

### $ -naphthylamines:

Included in the category are azo dyes which release a sulfonated $ -naphthylamine upon reduction of azo bonds. Also included in the category are N-acetylated sulfonated $

­ naphthylamines.
Haz a rd Concerns. Based on analogy to $ -naphthylamine per se , m emb ers of the class are considered potential carcinogens. A number of mono- and disulfonated $ -naphthylamines are positive in the Ames assay, and som e are active in the mouse lung adenoma assay. The presence of one or two sulfonate groups or the sulfatoet hylsulfone group is likely to slow systemic uptake and enhance excretion, however, the extent of these mitigating effects is unknown.
Boundaries. Concern is restricted to sulfonated $ -naphthylamines where not m o re than two sulfonate or sulfatoethylsulfone group(s) are on the ring distal to the $ -am i no group. The Agency has sufficient data to indicate that $ -naphthylam ines where a sulfonate group is on the proxim a l ring are unlikely to be carcinogenic. General Testing Strategy . The New Chemicals Program considers the following tests to be the m o st appropriate for monoand di-sulfonated $ -naphthylamines found to pose an unreasonable risk:

- An Ames test or, for azo dyes, an Ames test with the Prival modification, and - An unscheduled DNA synthesis test in rat hepatocytes. For azo dyes, it is necessary that the specific sulfonated $ -naphthylamine in question be isolated prior to testing. For both tests, $ -naphthylamine is to serve as an additional positive control. If the results of the genotoxicity testing indicate that the new chemical is genotoxic, a

80two- year, two-species cancer bioassay would be required. April 1991, updated June 1999

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------------------------------------ Category: Lanthanides or Rare Earth Metals Environmental Toxicity
Definition. This category includes inorganic salts, com p lexes organic acids, and organometallic com pounds or lanthanides or rare earth m e tals. There are 14 naturally-occurring lanthanides or rare earth m e tals:

Nam e Symbol MW CASRN Lanthanum La 139 [7439-91-0] Cerium Ce 140 [7440-45-1] Praseodymium Pr 141 [7440-10-0] Neodymium Nd 144 [7440-00-8] Sam a rium Sm 150 [7440-19-9] Europium Eu 152 [7440-53-1] Gadolinium Gd 157 [7440-54-2] Terbium Tb 159 [7440-27-9] Dysprosium Dy 163 [7429-91-6] Holmium Ho 165 [7440-60-0] Erbium Er 167 [7440-52-0] Thulium Tm 169 [7440-30-4] Ytterbium Yb 173 [7440-64-4] Lutetium Lu 175 [7439-94-3]

The lanthanide rare earth m e tals are very similar to each other. Their m o st im portant oxidation state is +3 for all. None are known to be essential to biological species. Across the lanthanide series from La to Lu, there is a general or steady decrease in their (1) atomic radii, (2) covalent radii, and (3) radii of their tripositve ions due to the addition of electrons at the 4f electron shell. This decrease in radii leads to a corresponding increase in the polarizing power of their ions and in the stability of com p lexes of their ions. They all have similar chemistry behaviors.
Haz a rd Concerns. The only toxicity data available for the lanthanide series are for La [7439- 91-0]. Soluble salts of La are known to have high chronic toxicity towards fish, m oderate chronic toxicity towards green algae, and low acute toxicity towards daphnids based on exposures in moderately hard water and in terms of m g La/L. Toxicity information are only available for La trichloride [10099-58-8] and La triacetate [917-70-4]. The toxicity profile for La based on available toxicity data, i.e., measured (M) and predicted (P), m g La/L (ppm La), and m oderate hardness (i.e., <180.0 m g /L as CaCO 3 ) is:

82fish 96-h LC50 < 1.0 P ACR10 daphnid 48-h LC50 = 160.0 M S,N BK59 green algal 96-h EC50 < 1.0 P EC50/ChV=4 fish chronic value(ChV) = 0.020 M SR12,M H104 B78 daphnid ChV = 20.0 P ACR10 algal ChV = 0.150 M S,N BK59

The lanthanides are assum e d to be m o re toxic in soft water than hard water based on data for other heavy m e tals.
Boundaries. The toxicity of the lanthanide rare earth m e tals depends on the their physical/chem i cal properties and the hardness of receiving waters. The toxicity of their salts and their com p lexes with organic acids are expected to be related to their water solubility, their MWs, and the stability of their com p lexes. The toxicity of lanthanide organometallic compounds, if they exist, are expected to be related to their octanol/water partition coefficient (Kow). The m o st important property determ ining the toxic ity of chemicals derived from lanthanide rare earth m e tals is their water solubility. Wa ter solubility cannot be estimated accurately and has to be measured. The water solubility of organometallic compounds is expected to decrease as Kow increases. There is no lower bound for Kow and the upper bound cannot be determined at this time since the Kow fragm e nt-constant for any of the lanthanide rare earth m e tals are not known. In addition to solubility, MW is also an important boundary. Highly stable com p lexes and organometallics with MWs > 1000 are not expected to be absorbed by aquatic organisms even if they are water soluble. Therefore, only lanthanide rare earth m e tal-compounds with MWs < 1000 are expected to be toxic. General Testing Strategy.
I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity tests for fish (40 CFR §797.1400 or OPPTS 850.1075) and daphnids (40 CFR §797.1300 or OPPTS 850.1010) will be done using the flow-through m e thod; effective concentrations will be based on 100% active ingredients (ai) and mean m e asured concentrations; the total organic carbon (TOC) concentration of dilution water in the control mu st be less than 2.0 m g TOC/L; TOC m u st be measured in the control just prior to the start of the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; solvent can be used to assist the compound to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the compound beyond its aqueous solubility limit; and hardness of dilution water has to be less than 180.0 m g /L as CaCO 3 . If toxicity mitigation testing is done with humic acid, then the static me thod with nominal concentrations will be recomme nded.

83The algal toxicity testing (40 CFR §797.1050 or OPPTS 850.5400), should be done with the static m e thod; effective concentrations based on 100% ai and mean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test me dium with no m o re than 0.300 m g /L EDTA as a final concentration; the TOC of the test/growth m e dium should be less than 2.0 m g TOC/L; TOC should be measured just prior to the start of the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; and solvent can be used to assist the compound to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the compound beyond its aqueous solubility limit. If toxicity mitigation testing is done with humic acid, then nominal concentrations will be recomme nded. If there is no significant risk from the chemical after the results of the environmental base set have been integrated into the risk assessment, then no f u rther testing will be recomm e nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR §797.1600 or OPPTS 850.1400), with the flow-thr ough m e thod; effective concentrations based on 100% ai and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; the TOC of dilution water in the control should be less than 2.0 m g TOC/L; TOC should be m easured in the controls just prior to and during the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; solvent can be used to assist the compound to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the compound beyond its aqueous solubility limit; and hardness of dilution water has to be less than 180.0 m g /L as CaCO 3 . Daphnid chronic toxicity testing (40 CFR §797.1330 or OPPTS 850.1300), with the flowthrough m e thod; effective concentrations based on 100% AI and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; the TOC of dilution water in the control should not exceed 2.0 m g TOC/L; TOC m u st be measured in the controls just prior to and during the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; solvent can be used to assist the compound to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the compound beyond its aqueous solubility limit; and hardness of dilution water has to be less than 180.0 m g /L as CaCO 3 . II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests will be recomme nded for terrestrial exposures. The terrestrial base set includes: the early seeding growth test (OPPTS 850.4230), the earthworm toxicity test (OPPTS 850.6200), the soil mi crobial comm unity bioassay (OPPTS 850.5100), and th e avian acute oral toxicity test (OPPTS 850.2100). Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test (OPPTS 850.4150), the plant uptake test (OPPTS 850.4800), and the avian reproduction test (OPPTS 850.2300 for bobwhite quail or for m a llard duck).

84February, 1998

85Category: Neutral Organics Environmental Toxicity

Definition. This broad category includes non-reactive non-ionizable organic chemicals such as alcohols, ketones, ethers, alkyl halides, aryl halides, and aromatic hydrocarbons.

Haz a rd Concerns. Neutral organics are environmentally toxic because of their ability to produce sim p le narcosis in aquatic species. Toxicity is a function of the octanol-water partition coefficient. Compounds with log P's of <5 e xhibit toxicity within 96 hours. At log P 5-8, toxicity is apparent only after extended exposure. Compounds with a log P >8 are not toxic at water saturation even after prolonged exposure. There are a number of QSARs (quantitative structure-activity relationships) to predict the toxicity of neutral organics.
Boundaries. The m o lecular weights of neutral organics of concern are generally less than 1,000. Log P is <8. QSAR predictions of toxic ity are constrained by water solubility. If a predicted toxicity level exceeds water saturation, then a longer test is needed to observe toxicity. General Testing Strategy To address ecotoxicity concerns, base set acute aquatic toxicity testing (algae (40 CFR 797.1050): static m e thod, daphnid (40 CFR 797.1300) and fish (40 CFR 797.1400): flowthrough m e thod, all measured concentrations).

86To properly assess any human and environmental toxicity or exposure, certain environmental fate properties, such as aerobic biodegradation, need to be measured. Aerobic biodegradability can be determined using one of the following test guidelines, listed in approxim a te order of preference: Aerobic aquatic biodegradation Modified Sturm test Closed bottle test Modified OECD screening test Modified MITI test (I) Modified AFNOR test 40 CFR 796.3100 40 CFR 796.3260 40 CFR 796.3200 40 CFR 796.3240 40 CFR 796.3220 40 CFR 796.3180 The physical state and electronic charge of the PMN substance should also be reported.
For som e neutral organics (e.g. ketones) dir ect/indirect photolysis (40 CFR 796.3765 and 796.3700) AND possibly biodegradation testing is recomme nded.
For som e neutral organics (e.g. alkyl halides) hydrolysis testing (40 CFR 796.3510) AND possibly biodegradation testing is recomme nded.
September 1988; revised October 1995

87Category: Nickel Compounds Hum a n Health Environmental Toxicity
Definition. Inorganic and organic compounds of nickel in which there is the potential for uptake of either Ni 2+ or organonickel.
Haz a rd Concerns. Nickel compounds e.g., nickel refinery dust, and its m a jor com ponent nickel subsulfide, have been shown to be carcinogenic in humans. Som e nickel compounds are known to be genotoxic. IRIS has established an oral RfD for the soluble salts of nickel of 2 x 10 -2 mg /kg/d (1992) based on effects on organ weights ina two-year feeding study in rats. In the study, there was a statistically significant reduction in total body weight, higher heart-to-body weight ratios and lower liver-to-body weight ratios than controls. In addition to the effects on organ weights found in the critical two-year study, two other sensitive endpoints exist, neonatal mo rtality and dermatotoxicity. Wh ile no reproductive effects have been associated with nickel exposure to humans, several studies in laboratory animals have demonstrated fetotoxicity. Soluble inorganic nickel compounds produce acute and chronic toxicity in freshwater and saltwater aquatic organisms over a wide range of concentrations but bioconcentrates only to a small degree. There are no known toxicity data for organonickel compounds.
Boundaries. Any nickel compound that will release Ni 2+ is considered hazardous. Conversely, there are no available data to suggest that nickel compounds in which the Ni 2+ is not released ma y pose a health hazard. The boundaries for ecotoxicity of Ni 2+ compounds depend on whether they are Ni 2+ salts, Ni 2+ chelates, or organonickel compounds. There is also a m o lecular weight boundary for strong ion pairs/com p lexes which is 1000. The boundaries for organonickel compounds (e.g., K ow undefined but the m o lecular weight boundary is expected to be 1000. of the organic portion) are
Occupational Exposure Controls. Because nickel compounds have been shown to be toxic by the inhalation/ingestion route, exposure controls that m a intain airborne exposures at 0.1 m g /m 3 or below are needed (consistent with OSHA PEL TWA). In addition, since nickel compounds are also toxic by the dermal route, NIOSH approved protective gloves are also recomme nded. Testing . D epending upon estimated workplace exposures and releases to water, which will be assessed on a case-by-case basis, the following testing m a y be recomme nded: To address health effects concerns due to the toxicity of nickel and its compounds, the following tests m a y be recomme nded: A 90-day subchronic study in rats by an appropriate route to assess systemic toxicity (OPPTS 870.3100 or 870.3250 or 870.3465)

88Results of the 90-day study m a y trigger a lifetime bioassay in rats and m i ce by the inhalation route to assess potential carcinogenicity (OPPTS 870.4200) To address ecotoxicity concerns due to toxicity of nickel and its compounds, the following base set tests m a y be recomme nded: Acute fish toxicity test OPPTS 850.1075 Acute daphnid toxicity test OPPTS 850.1010 Green algae toxicity test OPPTS 850.5400 All tests utilize measured concentrations.To properly assess human and environmental toxicity or exposure, certain physicochemical or environmental fate properties need to be measured:
Wa ter solubility Octanol/water partition coef fi cient (K ow ) Vapor pressure Melting point-melting range Boiling point OPPTS 830.7840 or 830.7860 OPPTS 830.7550 or 830.7560 or 830.7570 OPPTS 830.7950 or 830.8000 OPPTS 830.7200 OPPTS 830.7220 In addition, aerobic biodegradation by one of the following m e thods:
CO 2 evolution Closed bottle Modified OECD screening Modified MITI (I) DOC die-away Manometric respirometry

References. O PPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110

IRIS access. # 1271 (09/30/87) Nickel, soluble salts. OSHA PELs (1995-1996)
September 1996

89Category: Nonionic Surfactants Environmental Toxicity
Definition. Any neutral structure having surfactant activity is considered a m emb er of this category. Many of these surfactants have the following types of structure:

Ethoxylate groups m a y be m i xed with or be replaced by alcohol groups. Other neutral groups e.g. propoxylates, esters, halogens, m a y also be present.
Haz a rd Concerns. Acute aquatic toxicity increases exponentially with increases in the hydrophobic chain length when the number of ethoxy groups or the hydrophilic com ponent is held constant. In addition, when the number of carbons in the hydrophobe are constant, toxicity decreases with an increasing number of ethoxylate groups. The aquatic toxicity of m emb ers of the category can be predicted by structure-activity relationship (SAR).
Boundaries. There are no established m o lecular weight boundaries for this category. Lim its on chain length are inherent in the SARs. Testing. To address ecotoxicity concerns, base set acute aquatic toxicity testing (algae: static me thod, daphnid and fish: flow-through m e thod, all measured concentrations). Tier 1. The acute aquatic base setof environmental toxicity tests will be recom me nded for aquatic exposures and the terrestrial base setof environmental toxicity tests (i.e., the early seeding growth test, the earthworm acute toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for any terrestrial exposures. Acute fish toxicity test Acute daphnid toxicity test Green algae toxicity test Early seedling growth test Earthworm acute toxicity test Soil m i crobial comm unity bioassay OPPTS 850.1075 OPPTS 850.1010 OPPTS 850.5400
OPPTS 850.4230 OPPTS 850.6200 O PPTS 850.5100 Tier 2. If acute toxicity testing indicates a significant risk, then environmental fate testing in the form of aerobic biodegradation testing is recomme nded. Aerobic biodegradability can be determined using one of the following test guidelines:

90CO 2 evolution O PPTS 835.3110 Closed bottle OPPTS 835.3110 Modified OECD screening OPPTS 835.3110 Modified MITI (I) OPPTS 835.3110 DOC die-away OPPTS 835.3110 Manometric respirometry OPPTS 835.3110 Tier 3. In addition, if acute toxicity testing indicates a significant risk, then chronic aquatic toxicity testing with f i sh and aquatic invertebrates will be recomme nded. Fish early life stage test OPPTS 850.1400 Daphnid chronic toxicity testing O PPTS 850.1300
September 1988, revised September 1996

91Category: Organotins Hum a n Health Environmental Toxicity
Definition. This category includes all mono-, di-, tri- and tetra-alkyl or phenyl organotin compounds, including organotin esters/oxides. The mode of toxic action of organotins in humans is unknown, but they are known to affect carbonate m e tabolism and other m e tabolic processes in the brain, liver, and m u scle, as well as several enzym e s and the oxidative activity of m itochondria. It has been suggested that general sulfhydryl binding m a y be responsible for the effects seen in m amma ls. It is assum e d that these compounds need to be absorbed to be toxic, therefore, compounds with MWs > 1000 and which do not transform to organotin compounds with MWs < 1000 will be excluded from this category. Hum a n health and aquatic toxicity for liquid organotins is assum e d to be limited by the relative octanol/water partition coef fi cient (a relative K ow is based on the computer program, CLOGP, with C substituted f o r Sn). However, the limiting relative K ow value is unknown. The Agency has data for an organotin with a relative log K ow = 13.7 which still showed high toxicity towards fish and daphnids. Organotins which are solids at room tem p erature m a y show no toxicity at saturation at log K ow values < 13.7 depending on the m e lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no toxicity will be observed at saturation. For solids, the no-effects-at-saturation determination has to be m a de on a case-by-case basis. There are no known K ow limits f o r acute and chronic environmental toxicity at this time, but it is higher than a log K ow = 13.7. Future testing w ill determine the K ow limits.

Haz a rd Concerns. Tested organotins have been shown to be from m oderately irritating to corrosive to the skin and eyes. Acute oral and derm al exposures can result in systemic effects, primarily neurotoxicity. Concerns for imm unotoxicity are based on data on dialkyltins and trialkyltins. During a 13-week oral study in rats using dioctyltin bis (2-ethylhexylthioglycolate), effects to the thymus, spleen, lymph nodes, and bone m a rrow were observed. A No-ObservableAdverse-Effect-Level (NOAEL) of 1.6 mg/kg/d wa s derived from this study. During a 17-month feeding study in rats using bis (tri-n-butyltin)-oxide, imm unoglobulin E (IgE) titers were reduced, as well as the activity of natural killer cells in the spleen, and there was reduced m acrophage function. A NOAEL of 0.025 m g /kg/d wa s derived from this study. Based on the imm unotoxicity end-point, an oral reference dose for chronic exposure (RfD) for tributyltin

92oxide of 3 x 10 -5 mg /kg/d (IRIS 01/01/89) has been derived. Organotins are well known neurotoxins, with the tri- and tetra-substituted tins being m o re toxic than the mono- and disubstituted compounds. Although m a ny tri-alkyltins show clear neurotoxic effects (eg. lesions in the hippocampus), the neurotoxic potential of di-alkyltins has not been as well def i ned. Available data indicate that dibutyltin and di octyltin can produce neurotoxic effects such as reductions in brain neurotransmitter levels, alterations in spontaneous m o tor activity and hindlimb weakness. An effect level for neurochem i cal and behavioral changes following 3 days of oral adm i nistration of dibutyltin dilaurate was reported as 20 m g /kg. There are oncogenicity concerns for som e of the organotins based on analogy to triphenyltin hydroxide, a group B probable human carcinogen. Therefore, the human health concerns for phenyltins will be dealt with on a case-by-case basis. The acute aquatic toxicity for several subclasses of organotins has been determined through toxicity testing (Vighi & Calam a ri, 1985; Wong et al. 1982) and structure activity relationships (SAR). Organotins have been shown to be highly toxic to green algae (Wong et al. 1982). The acute toxicity of organotins is moderate to high towards daphnids (Vighi & Calam a ri, 1985). One datum for fish has indicated high toxicity (USEPA 1996). Organotins exhibit toxicity ranging from m oderate toxicity (i.e., > 10 m g /L) to high toxicity (i.e., < 1 m g /L) depending on their K ow , m e lting point, and MW

. The higher the K ow , the higher the toxicity (or the lower the EC 50 value).
Boundaries. There are no known boundaries. The upper boundaries will be based on K ow and MW

. Acute toxicity expected with log K ow < 13.7; chronic toxicity has no known upper bound for log K ow , but it is > 13.7. MW will be < 1000 for stable compounds. The environmental base set of tests will be requested f o r aquatic releases and the terrestrial base set of tests will be recomme nded for terrestrial exposures. General Testing Strategy.
TIER 1.
A 90-day subchronic test in rodents by the oral route with special attention to the lymphoid organs (thymus, spleen, peripheral lymph nodes) and bone m a rrow (OPPTS 870.3100). Neurotoxicitytesting to include m o tor activity, a functional observational battery and neuropathology with special attention to lesions in the hippocampus (OPPTS 870.6200). This testing can be com b ined with the 90-day subchronic protocol cited above. The acute aquatic base setof environmental toxicity tests will be recom me nded f o r aquatic exposures and the terrestrial base setof environmental toxicity tests will be recom me nded f or terrestrial exposures. The acute toxicity tests for fish and daphnids should be done using the flow-through m e thod with measured concentrations. Effective concentrations should be based on 100% active ingredients (AI) and mean measured concentrations. Measure TOC of dilution water in the control just prior to testing. Ideally, the highest treatm e nt concentration on a mean

93m easured concentration-basis should equal the aqueous solubility limit. Solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to significantly enhance the water solubility. The algal toxicity testing should be done with the static m e thod and m easured concentrations. Statistical analysis of effective concentrations at 24, 48, 72, and 96 hours should be perform e d. The test m e dium should be used with at least 0.300 m g /L EDTA as a final concentration. Aquatic Base Set Acute fish toxicity test Acute daphnid toxicity test Green algae toxicity test Terrestrial Base Set Early seedling growth test Earthworm acute toxicity test Soil m i crobial comm unity bioassay
TIER 2. OPPTS 850.1075 OPPTS 850.1010 OPPTS 850.5400

OPPTS 850.4230 OPPTS 850.6200 O PPTS 850.5100

If acute aquatic toxicity testing indicates a significant risk, the following environmental fate testing is recomme nded to determine aerobic biodegradabilityusing one of the following test guidelines:
CO 2 evolution Closed bottle Modified OECD screening Modified MITI (I) DOC die-away Manometric respirometry
TIER 3. O PPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110 OPPTS 835.3110

If acute toxicity testing and environmental fate testing continue to indicate a significant risk, then chronic aquatic toxicitytesting with fish and aquatic invertebrates is recomme nded with flowthrough m e thods and measured concentrations. Effective concentrations should be based on 100% active ingredients (AI) and mean measured concentrations. Conduct statistical analysis of effective concentrations at days 7, 14, 21, and 28. Measure TOC of dilution water in the control just prior to testing. Ideally, the highest treatm e nt concentration on a mean measured concentration-basis should be equal at the aqueous solubility limit. Solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to significantly enhance the water solubility. The 7-d fish early life stage (ELS) toxicity test cannot be substituted for the 28-d ELS toxicity test and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test because Van Leeuwen et al. (1990) have demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28-d

94ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). Chronic Aquatic Toxicity Fish early life stage test OPPTS 850.1400 Daphnid chronic toxicity testing O PPTS 850.1300
References.
8E-594. Tributyltin oxide. Bis-(tri-n-butyltin)-oxide

. (1988, December). Gesellschaft Deutscher Chemiker - Advisory Comm ittee on Existing Chemical of Environmental Relevance (BUA). BUA Report 36. USEPA 1996. United States Environmental Protection Agency (1996). The Office of Pollution Prevention andToxics (OPPT) premanufacture notification (PMN) ECOTOX database: a confidential business information (CBI) collection of environmental toxicity data from new chemical submissions under Sec. 5 of the Toxic Substances Control Act (TSCA). Wa shington, DC: Environmental Effects Branch, Health and Environmental Review Division (7403), OPPT, USEPA. OPPT contact is V. Nabholz, 202-260-1271. Van Leeuwen, C.J., Adema, D.M.M., & Hermens, J. (1990). Quantitative structure-activity relationships for fish early life stage toxicity. Aquatic Toxicology, 16, 321-334. Vighi, M., & Calam a ri, D. (1985). QSARs for organotin compounds on Daphniamagna
. Chemosphere, 14, 1925-1932.
W HO 1980. Wo rld Health Organization Environmental Health Criteria 15. Tin and organotin compounds: A preliminary review. Geneva: WHO pp. 59-62. Wong, P.T.S., Chau, Y.K., Kramar, O., & Bengert, G. A. (1982). Structure-toxicity relationship of tin compounds on algae. Canadian Journal of Fisheries and Aquatic Sciences, 39, 483-488.
April 1991, revised September 1996

95Category: Peroxides Hum a n Health (case-by-case) Environmental Toxicity
Definition. Any m o lecular structure containing one or m o re of the following functional groups is considered to be a m emb er of the class: | | -C-O-O-C­

| | | -C-O-O-H

|
O 5 | -C-O-O-C­ |
O O 5 5 -C-O-O-C-

O 5 -C-O-O-H dialkyl peroxide

alkyl hydroperoxide

peroxy ester

diacyl peroxide

peroxy acid The category of peroxides is a small one (<0.2% of all new chemicals). The "typical" peroxide in the new chemical program is a discrete (class I) chemical with a m o lecular weight of <500.
Haz a rd Concerns. EPA had previously identified hazard concerns for the possible carcinogenicity of new chemicals falling into the peroxide category based on available evidence. EPA has reviewed test data developed by the Soci ety of the Plastics Industry (SPI) and others on the peroxide category of chem icals and concludes that available information does not support continued identification of peroxides as a new chemical category presenting concerns for possible carcinogenicity. EPA will continue to evaluate the potential health concerns for new chemical peroxides that are notified but, with this change, will not apply a category understanding as regards potential carcinogenicity. Wh ile the assessment of potential human health hazard concerns will be conducted on a case-by-case basis, this modification does not affect EPA’s approach to environmental hazard concerns which will continue to be identified for memb ers of this category.
Boundaries. There are no established boundary conditions for review of peroxides. General Testing Strategy .

96The New Chemicals Program considers the following tests to be appropriate to address ecotoxicity concerns for peroxides: 1. Base-set ecotoxicity testing to incl ude fish (40 CFR 797.1400), daphnids (40 CFR 797.1300), and algae (40 CFR 797.1050). 2. Environmental fate testing including, as appropriate, m e lting point (40 CFR 796.1300) or boiling point (40 CFR 796.1220), water solubility (40 CFR 796.1840 or 796.1860), log K ow (40 CFR 796.1550, 796.1570, or 796.1720), vapor pressure (40 CFR 796.1950), hydrolysis (40 CFR 796.3500), direct and indirect photolysis (40 CFR 796.3765), and aerobic biodegradation by anyof the following test guidelinesModified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180 September, 1988; revised June, 1994; revised April, 2001

97Category: Persistent, Bioaccumulative, Environmental Fate and Toxic (PBT) Chemicals Health/Environmental Toxicity

Definition. PBT chemical substances possess characteristics of persistence (P) in the environment, accum u lation in biological organisms (bioaccum u lation (B)), and toxicity (T) that ma ke them priority pollutants and potential risks to humans and ecosystems. Prominent examples of PBT chemical substances include the insecticide, DDT and polychlorinated biphenyls (PCBs). This PBT category includes the boundary conditions, such as fish bioconcentration/bioaccum u lation factors and environmental persistence values, that would determine inclusion in (or exclusion from) the category, and standard hazard and fate tests to address P, B, and T concerns for the chemical substances fitting the category description. For background information and discussion of this PBT category, see http://www.epa.gov/oppt/newchems/pbtpolcy.htm , and the proposed (October 5, 1998; 63 FR 53417) and final (Novem b er 4, 1999; 64 FR 60194) “C ategory for Persistent, Bioaccumulative, and Toxic Chemical Substances” published in the US Federal Register.
Haz a rd Concerns. Generally, PBT chemical substances are chemical substances that partition to water, sedim e nt or soil and are not removed at rates adequate to prevent their bioaccumulation in aquatic or terrestrial species, with the potential to pose a risk via food chain toxicity.
Boundaries. The following table summa rizes specific identification criteria and associated process for use in evaluating new chemical PBT substances.
NEW CHEMICALS PROGRAM PBT CATEGORY CRITERIA AND PROCESS TSCA Section 5 Action 5(e) Order/Significant New Use Rule (SNUR) Exposure/release controls included in order; testing required Ban Pending Testing Deny comme rcialization; testing results may justify removing chemical from “high risk concern”
Persistence (transformation half-life) >2 months >6 months

Bioaccum u lation* (Fish BCF or BAF) >1000 >5000 Toxicity Develop toxicity data where necessary, based upon various factors, including concerns for P, B, other physical/chem i cal factors, and toxicity.
* Chemicals m u st also meet criteria for MW(<1000) and cross-sectional diameter (<20 D , or <20 x 10 -8 cm). BCF of 1000 and 5000 are equivalent to log Kow of 4.2 and 5, respectively.

98General Testing Strategy
Tier 1 . Based upon SAR and professional judgme nt, the Agency identifies a new chemical substance as a possible PBT chemical substance.

Log Kow Liquid chromatography (OPPTS 830.7570/OECD 117) or generator column(OPPTS 830.7560) m e thod Ready biodegradability Ready biodegradability (OPPTS 835.3110/OECD 301) 6 me thods (choose one, or an equivalent test): DOC DieAway, CO 2 Evolution, Modified MITI (I), Closed Bottle, Modified OECD Screening, Manometric Respirometry or Sealed-vessel CO 2 production test (OPPTS 835.3120) Hydrolysis in water (if, based upon SAR, susceptibility to hydrolysis is suspected) OPPTS 835.2110 (OECD 111)

Results If the measured log Kow is <4.2 or if the test chemical passes the ready biodegradability test (i.e., not persistent in the environment), no further PBT-related testing is required. If the measured log Kow is greater than or equal to 4.2 and the chemical does not pass the ready biodegradability test, the chemical would require tier 2 testing. If hydrolysis testing is conducted and results in a half-life of <60 days, further testing m a y not be needed, but the need for testing mu st be determined after consideration of factors specific to the case, such as physical/chem i cal properties, persistence and bioaccum u lative qualities of hydrolysis products, and the nature of the expected releases.

99Tier 2. Biodegradability and Bioaccumulation Biodegradability Shake-flask die-away test (OPPTS 835.3170) or an equivalent test. Bioaccum u lation F ish bioconcentration test (OPPTS 850.1730/OECD 305), or an equivalent test). Measured BCF should be based on 100 percent active ingredient and m easured concentration(s). Results If the measured biodegradation half-life is >60 days and m easured BCF is >1000, tier 3 testing will be required. If only one condition is m e t, releases and exposure are further considered to determine if additional testing is required.
Tier 3 . Toxicity/advanced environmental fate testing.

Hum a n health toxicity Com b ined repeated dose oral toxicity with the reproductive/developmental toxicity screening test (OECD No. 422) in rats. Other health testing will be considered where appropriate. Environmental fate Sedim e nt/water m i crocosm biodegradation test (OPPTS 835.3180). Chronic environmental toxicity Fish (rainbow trout) and daphnids should be tested according to 40 CFR 797.1600 (same as OPPTS 850.1400/OECD 210) and 40 CFR 797.1330 (same as OPPTS 850.1300/OECD 202), respectively. Additional testing to evaluate other biota (e.g., avian, sedim e nt dwelling organisms) or other effects (e.g., endocrine disrupting potential) will be considered where appropriate.
Novem b er, 1999

100Category: Phenolphthaleins Hum a n Health
Definition. Any chemical containing the phenolphthalein structure is considered to be a m emb er of the category.

Haz a rd Concerns. The health concern for phenolphthalein and derivatives of phenolphthalein is for cancer based on the NTP cancer study (NTP report TR-465, Novem b er 1996) for phenolphthalein with adm i nistration via the di et. There was clear evidence of carcinogenic activity in m a le F344/N rats based on m a rkedly increased incidences of benign pheochromocytomas of the adrenal m e dulla and of renal tubule adenomas and adenomas or carcinomas (combined). There was som e evidence of carcinogenic activity in fem a le F344/N rats based on the increased incidences of benign pheochromocytomas of the adrenal m e dulla in the 12,000 ppm group and of benign or m a lignant pheochromocytomas (combined) in the 12,000 and 25,000 ppm groups. There was clear evidence of carcinogenic activity in m a le B6C3F 1 mi ce based on increased incidences of histiocytic sarcomas and of m a lignant lymphomas of thymic origin. There was clear evidence of carcinogenic activity in fem a le B6C3F 1 mi ce based on increased incidences of histiocytic sarcomas, m a lignant lymphomas of all types, lymphomas of thymic origin, and benign sex-cord strom a l tum o rs of the ovary.
Boundaries. No boundaries currently defined.

101Testing. EPA considers the following tests to be the m o st appropriate for phenolphthalein derivatives found to pose an unreasonable risk to human health: Tier 1:
Com p arative dermal and oral absorption study in rats (OPPT Harm onized Test Guidelines, 870.7485) in vitro Chrom o som e aberrations study in Chinese ham s ter ovary cells with phenolphthalein as an additional positive control (OPPT Harmonized Test Guidelines, 870.5375) Log Kow test (OPPTS 830.7550)
W a ter solublility for both lactone and acid form (OECD 105) Ready biodegradability (OPPT 835.3110) Tier 2: 2-year carcinogenicity study in m i ce (OPPT Harmonized Test Guidelines, 870.4200) April, 1998

102Category: Phenols Environmental Toxicity
Definition. This category includes phenols (i.e., monophenols), polyhydroxy phenols, and polyphenols. It is assum e d that these compounds need to be absorbed to be toxic, therefore, compounds with MWs > 1000 will be excluded from this category. Acute toxicity for phenols which are liquids at room tem p erature is known to be limited by the octanol/water partition coefficient (K ow ). Above a log K ow value of about 7.38, phenols are expected to show no effects at saturation during 96-h exposures (Veith and Broderius 1987). Phenols which are solids at room tem p erature m a y show no toxicity at saturation at lower K ow values depending on the me lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no toxicity will be observed at saturation. For solids, no effects at saturation has to be demonstrated on a case-by-case basis. There are no known K ow limits f o r chronic toxicity at this time, but it ma y not be m u ch above a log K ow = 9.0 for liquid phenols. Future testing will determine this K ow limit.
Haz a rd Concerns

. T he acute and chronic toxicity for phenols can be predicted through SAR Analysis. SARs are available for fish 96-h LC50, daphnid 48-h LC50, green algal 96-h EC50, fish chronic value (ChV), daphnid ChV, and al gal ChV. Mem b ers of this category exhibit toxicity ranging from low toxicity (i.e., > 100 m g /L) to high toxicity (i.e., < 1 m g /L) depending on their K ow , MW, and substitutions (e.g., dinitrophenols). Dinitrophenols are known to be m o re toxic than predicted by these SARs (see the category for polynitroarom a tics).
Fate : Phenols are subject to indirect photolysis under environmentally realistic conditions.
Boundaries. There are no known lower boundaries. The upper boundaries will be based on K ow and MW

. Acute toxicity expected with log K ow < 7.38; no effects at saturation during 96-h exposures when log K ow >= 7.38. Chronic toxicity has no known upper bound for log K ow , but it is probably near 9. MW will be < 1000. The environmental base set of tests will be requested fo r aquatic releases and the terrestrial base set of tests will be recom me nded f o r terrestrial exposures. Wh en the log K ow is >= 7.38, chronic toxicity testing with fish, daphnids, and green algae will be recomme nded. General Testing Strategy
I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity tests for fish (40 CFR 797.1400) and daphnids (40 CFR 797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should equal the aqueous solubility limit; and solvent can be

103used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. The algal toxicity testing (40 CFR 797.1050), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% AI and mean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test me dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm ent concentration on a nominal-basis equal to the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. If there is no significant risk from the PMN after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Direct and Indirect Photolysis Screening Test (40 CFR 796.3765). If t1⁄2 < 2 days, go to Tier 3; if t1⁄2 > 2 days, go to Tier 4. Tier 3a. If t1⁄2 < 2 days and photolysis products are known and/or identified, then assess photolysis products for environmental hazards. Tier 3b. If t1⁄2 < 2 days and photolysis products are not known and/or identifiable, then prepare a stock solution of PMN using the sta ndard humic-containing solution described in the direct and indirect photolysis screening te st [40.796.3765 (b)(2) and (c)(2)], expose to sunlight for at least 6 half-lives (t1⁄2), and test photolysis products for toxicity with m o st sensitive species fr om environmental base set. For example, the m o st sensitive species f r om the environmental base set has an EC50 value = 2.0 m g PMN/L (based on 100% AI, therefore, prepare a 5.0 m g PMN per liter stock solution based on 100% AI using the standard humic-containing solution. This stock solution is exposed to sunlight for at least 6 half-lives to ensure that all of the PMN has been photolyzed, and then this stock solution is used to retest the m o st sensitive aquatic species to determine if the photolysis products of the PMN are m o re or less toxic that the PMN. Tier 4. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR 797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% AI and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because Van Leeuwen et al (1990) have demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen);

104Daphnid chronic toxicity testing ( 40 CFR 797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% AI and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; me asured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted f o r the 21-d toxicity test because Van Leeuwen et al (1990) have demons trated that the fish 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the fish 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay.
References. Van Leeuwen CJ, Adema DMM, and Hermens J. 1990. Quantitative structure-activity relationships for fish early life stag e toxicity. Aquatic Toxicology 16:321-334. Veith GD and Broderius SJ. 1987. Structure-toxi city relationships for industrial chemicals causing type (II) narcosis syndrome. In Kaiser KLE (ed), QSAR In Environmental Toxicology - II, p 385-391. Reidel Publishing Com p any. July, 1991

105Category: Phosphates, Inorganic
Definition. This category includes all inorganic soluble forms of phosphates, such as, phosphoric acid [PO4H3 or OP(=O)(O)O] and its salts or phosphate salts, pyrophosphates, polyphosphates, and organic and inorganic fo rms of phosphorous that can be oxidized to phosphates rapidly. Inorganic forms of phosphonic acid (H2PO3 or OP(=O)O) are not included in this category because monopotassium phosphonic acid [13977-65-6] has been shown not to be an algal nutrient, not to be a replacement for phosphate in algal growth m e dium, and not to cause exponential growth of green algae.
Haz a rd Concerns. The standard environmental toxicity profile for inorganic phosphates as P in mg P/L is: ECOTOX: Predicted (P) and measured (M) toxicity values in m g /L (ppm) are: fish 96-h LC50 > 100.0 P daphnid 48-h LC50 > 100.0 P green algal 96-h EC50 b < 0.030 P algal 96-h EC290 b = 0.030 M S,N fish chronic value > 10.0 P daphnid ChV > 10.0 P algal ChV = 0.010 M Hutchinson 1957 Predictions are based on SAR-nearest analog analysis for soluble forms of inorganic phosphates (PO4); SAR chemical class = P-O4; MW of P = 31, PO4 = 95, PO4H3 = 98; pH7; effective concentrations based on 100% active ingredients and nominal concentrations of P; hardness <24.0 m g /L as CaCO3; and TOC <2.0 m g /L; high concern for eutrophication; assessment factor = 10.0 concern concentration = 0.001 Phosphate phosphorus has the potential to stimulate the growth of green algae and cause algal blooms and eutrophication in freshwater a nd m a rine environments. The phosphate anion is a plant nutrient and is the m a jor limiting nutrient in m a ny freshwater environments. The USEPA OW WQ C (USEPA 1976) states: [W]hen such concentrations [of total phosphate phosphorus]exceed 25 

### : g/l at the time of the spring turnover on a volume-weighted basis in lakes or reservoirs, they m a y occasionally stimulate excessive or nuisance growths of algae and other aquatic plants. Algal growths impart undesirable tastes and odors to water, interfere with water treatm e nt, becom e aesthetically unpleasant and alter the chemistry of the water supply. The contribute to the phenomenon of cultural eutrophication. To prevent the development of biological nuisances and to control accelerated or cultural eutrophication, total phosphates as phosphorus (P) should not exceed 50 

### : g/l in any stream at the point where it enters any lake or reservoir, nor 25 

### : g/l within the lake or reservoir. A desired goal for the prevention of plant nuisances in streams or other flowing waters not discharging
106directly to lakes or impoundments is 100 

### : g/l total P (Mackenthum, 1973). Most relatively uncontaminated lake districts are known to have surface waters that contain from 10 m i crogram s P/L (or 31 m i crograms PO4H3/L) to 30 m i crog P/L (or 92 m i crog PO4H3/L) (Hutchinson, 1957). Odum (1971) called phosphorus a m a jor factor in the process of cultural eutrophication. Eutrophication results when nutrients, especially phosphates, are imported into aquatic ecosystems. This process is analogous to fertilizing an agricultural field. Phosphates act like a fertilizer and produce increases in the abundance of algae and other aquatic plants; eventually, they can result in excessive growths of algae (i.e., algal blooms). Excessive algae can block sunlight from reaching submerged macrophytes and other m i croalgae below the surface. Wh en the algae die and fall to the bottom of slow-m oving water or lakes, they are consumed by bacteria which use up available oxygen producing anaerobic conditions. Decaying algae cause odors and oxygen depletion of the water to occur with concomitant detriment to fish and aquatic invertebrates and, in turn, fishing and water-based recreational activities. Phosphate concentrations as low as 0.050 m g P/L (ppm ) or 50.0 m i crogram s P/L (ppb) will produce exponential growth of green algae in 96 hours (Miller et al. 1978), and phosphate concentrations from 10 to 60 m i crograms P/L (ppb) were correlated to algal blooms and oxygen depletion (i.e., eutrophication) in Lake W a shi ngton, Seattle (Odum 1971). Phosphates have been severely limited or banned from detergents in 13 states, the District of Colum b ia, and several counties and municipalities (USEPA 1992). Sodium tripolyphosphate was one of the principal components of synthetic detergents. Freshwater green algae are clearly the m o st sensitive group of aquatic organisms to phosphate additions to water.
Boundaries. The boundaries for inorganic phosphate compounds depend on the release of inorganic phosphates which can be used by algae as a m i neral nutrient. Any inorganic phosphate which can be used by algae as a nutrient or which transform s to release or becom e s an algal nutrient is included in this category. Testing. Based on a consideration of available data on inorganic phosphates and the physicochem i cal properties of these compounds, there is no need for further testing. However, if there is doubt about the availability of phosphate in a nutrient form from a PMN substance, then the algal toxicity test can be done with the PMN substance substituted for phosphate nutrient in the algal growth m e dium

. If a PMN substance is capable of stimulating exponential growth green algae, it m u st be em phasized that inorganic phosphates should not be released to water because of their potential to cause eutrophication and their persistence. Regulatory Actions. (1) Phosphates have been severely limited or banned from detergents in 13 states, the District of Colum b ia, and several counties and municipalities (USEPA 1992). (2) W a ter Quality Criterion, 1976 (USEPA 1976): total phosphates as phosphorus (P) should not exceed 50 m i crograms p/L in any stream at the point where it enters any lake or reservoir, nor 25 m i crograms P/L within the lake or reservoir.

107(3) Hazard assessments of selected aqueous cleaner chemicals, USEPA (1990): OPPT recomme ndation to the Office of Air and Radiation: "...phosphates should never be released to water." (4) Agency recomme ndation for a "nationwide elimination of the use of household laundry detergents containing phosphates." (USEPA 1992).
References. Hutchinson, G. E., 1957, A treatise on limnology. New York, NY: John Wiley & Sons. Mackenthun, K. M., 1973, Toward a cleaner aquatic environment. Wa shington, DC: USEPA. Miller, W

. E., Greene, J. C., and Shiroyam aT. 1978. The Selenastrumcapricornutum Printz algal assay bottle test. Corvallis, OR: USEPA, Of fi ce of Research and Developmental, Environmental Research Laboratory-Corvallis, EPA-600-9-78-018. United States Environmental Protection Agency (USEPA). 1976. Quality Criteria for W a ter. EPA-440/9-76-023. Wa shington, DC: Office of W a ter Planning and Standards, OW, USEPA. Available from NTIS, Springfield, VA 22161, PB-263-943. United States Environmental Protection Agency (USEPA). 1990. (Health and environmental effects of selected aqueous cleaner chemicals. Wa shington, DC: Health and Environmental Review Division, Office of Polluti on Prevention and Toxics, USEPA. United States Environmental Protection Agency (USEPA). 1992. ( DRAFT Phosphate detergents: An evaluation of the benefits and co sts of eliminating their use in the United States. Wa shington, DC: Environmental Results Bran ch, Office of Policy, Planning, & Evaluation, USEPA. March, 2000

108Category: Phosphinate Esters Environmental Toxicty Phosphinate esters are a class of organic compounds characterized by the functional group R-O-P(=O)(R)R. Phosphinate esters are m e tabolically active and exhibit excess aquatic toxicity in addition to narcosis. Phosphinate esters exhibit excess toxicity relative to sim p le esters (-C(=O)O-) and phosphate esters (-OP(=O)(O-)O-. It is assum e d that phosphinate esters need to be absorbed to be toxic, therefore, phosphinate esters with MW >1000 will be excluded from this category. Acute toxicity for phosphinate esters is known to be correlated and limited by the octanol/water partition coefficient (K ow ). Above a log K ow value of >5.0, phosphinate esters show no effects at saturation during 96-hr exposures to fish. Phosphinate esters which are solids at room tem p erature m a y show no toxicity at saturation at lower K ow values depending on the m e lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no toxicity will be observed at saturation. For solids, the no effects at saturation has to be determined on a case-by-case basis. There are no measured upper K ow limits f o r chronic toxicity at this time, but it m a y not be m u ch above a log K ow = 8. Future testing will determine K ow limits.
Haz a rd Concerns. The toxicity for phosphinate esters has been determined through SAR analysis. SARs for freshwater species: log fish 96-h LC 50 (millimoles/L) = -1.201 -0.260 log K ow where n=2, R2 =1.0, LOGKOW (SRC)<5, MW<1000; log daphnid 48-h LC 50 (millimoles/L) = -1.501 -0.260 log K ow (SRC)<5, MW<1000; where n=2, R2 =1.0, LOGKOW
log green algal 96-h EC 50 (mmo l/L) = -1.974 -0.332 log K ow where n=2, R2 =1.0, LOGKOW(SRC)<6.4, MW<1000, based on test data for Pseudomonas putida ; log fish ChV (millimoles/L) = -2.210 -0.499 log K ow where n=2, R2 =1.0, LOGKOW(SRC)<8, MW<1000, based on F96÷ACR10; log daphnid ChV (millimoles/L) = -2.445 -0.407 log K ow where n=2, R2 =1.0, LOGKOW(SRC)<8, MW<1000, based on D48÷ACR10; and log algal ChV (mmo l/L) = -3.315 -0.223 log K ow where n=2, R2 =1.0, LOGKOW(SRC)<8, MW<1000, based on test data for Pseudomonas putida

. SARs for saltwater species: log fish 96-h LC 50 (millimoles/L) = -1.160 -0.368 log K ow
109where n=2, R2 =1.0, LOGKOW(SRC)<5, MW<1000; and log my sid 96-h LC 50 (millimoles/L) = -2,019 -0.476 log K ow where n=2, R2 =1.0, LOGKOW(SRC)<5, MW<1000.
Fate. Phosphinate esters hydrolyze in water and their rate of hydrolysis is correlated with pH: the m o re alkaline the faster the hydrolysis. The SAR for hydrolysis is: log hydrolysis t1⁄2 (d) = 4.325 -0.497 pH where n=2, R2 =1.0. At pH 7.1, the hydrolysis t1⁄2 = 6.3 days or 150 hours.
Boundaries. MW <1000. Log K ow <5.0 for acute toxicity to fish and aquatic invertebrates; log K ow <6.4 for toxicity to green algae as a 96-h EC 50 ; and log K ow assum e d to be <8.0 for chronic toxicity to aquatic organisms, but could be higher. General Testing Strategy. I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity test s for fish (OPPTS 850.1075) and daphnids (OPPTS 850.1010) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (ai) and mean measured concentrations; m easured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; and solvent can be used to assist the aldehyde to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the test chemical significantly above its aqueous solubility limit. The algal toxicity testing (OPPTS 850.5400), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (ai) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; ideally, mean m easured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; and solvent can be used to assist the aldehyde to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the test chemical significantly above its aqueous solubility limit. If there is no significant risk from the PMN chemical after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2.

110Tier 2. Aerobic biodegradability according to either of the following test guidelines: Ready Biodegradability OPPTS 835.3110 Sealed Vessel CO2 Production Test OPPTS 835.3120 If there is no significant risk from the PMN chemical after the results of biodegradation testing have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 3. Tier 3. Fish chronic toxicity testing, i.e., fish early life stage (ELS) toxicity testing (OPPTS 850.1400), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrati ons at days 7, 14, 21, and 28; me asured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN significantly above its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because the 7-d ELS toxicity test m a y underestimate chronic toxicity measured by the 28-d ELS toxicity test when the Chronic Values are com p ared. Daphnid chronic toxicity testing (O PPTS 850.1300), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean m easured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; ideally, mean measured concentrations in the highest treatm e nt concentration should be equal the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN significantly above its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test because the daphnid 7-d short-term chronic toxicity test m a y underestimate chronic toxicity m easured by the daphnid 21-d chronic toxicity test when the chronic values are com p ared.
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test [O PPTS 850.4230], the earthworm toxicity test [OPPTS 850.6200], and the soil m i crobial comm unity bioassay [OPPTS 850.5100]) will be recomme nded for terrestrial exposures. Chronic toxicity te sting for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay. September 1996.

111Category: Polyanionic Polymers (& Monomers) Environmental Toxicity
Definition. There are two subcategories of polymers that are of concern: - polyarom a tic sulfonates - condensation products of sulfonated aromatics with formaldehyde, and - polyacrylates with free carboxyl groups. This category includes monomers with two or m o re acid groups and which act like organic acid chelators. The acid groups m a y include carboxylic acids, silicic acids, phosphoric acid, and sulfuric acids. These acids m a y also contain thiol substitutions. The acid groups on a monomer ma y be all of the sam e type of acid or m a y be a m i xture of acids. The monomeric nucleus m ay include carbon, silica, oxygen, sulfur, and nitrogen, or m i xtures of these elements. Mem b ers of this category m u st be water soluble or water self-dispersing. Molecular weights can be > 1000.
Haz a rd Concerns. Polyaromatic sulfonates are m oderately toxic to fish, daphnids, and algae. The polyacrylates are toxic to algae only. There is no apparent relationship between charge density and toxicity, and no QSAR (quantitative structure-activity relationship) has been developed for these polymers, or the polyanionic monomers. Polyanionic monomers (as salts, e.g., Na or K salts) are moderately toxic to green algae, but show low toxicity to fish and daphnids. It is assum e d that the toxicity of these compounds is due to over-chelation of nutrient elements needed f o r algal growth and that this toxicity will be mitigated in the presence of Ca ++ either added to the compound before testing or present in the growth/test m e dium at a hardness of about 150 mg/L as CaCO 3 . Boundaries. Polym e rs m u st be water-soluble. Molecular weights are generally >1,000. General Testing Strategy To address ecotoxicity concerns, for polycar boxylic acids (polyacrylates) and polyanionic m onomers, algal testing (static m e thods, nominal concentrations) is recomme nded, in 3 separate tests: 1) the test substance as is, 2) with equiva lent of calcium ion, and 3) with growth m e dium at 150 m g /L hardness, as CaCO 3 ). For polyarom a tic sulfonates, base set aquatic toxicity testing (flow through m e thods, measured concentrations) in algae, daphnids, and fish is recomme nded. September, 1988; revised April, 1991

112Category: Polycationic Polymers Environmental Toxicity
Definition. Any polymer that exists in the environment with m u ltiple positive charges is a memb er of this class. Such structures include polyam i nes, polyquaternary am m onium , polysulfonium, and polyphosphonium compounds.
Haz a rd Concerns. Mem b ers of the category are toxic to fish, invertebrates, and algae. Algae are six-fold m o re sensitive than fish and daphnids. It is presumed that these compounds act on the surface of organisms and need not be absorbed. Toxicity increases exponentially with increasing charge density at cationic equivalent weights of >400. At lower charge equivalent weights, toxicity does not increase. A number of QSARs (quantitative structure-activity relationships) have been developed to predict the toxicity of polycationic polymers.
Boundaries. Polym e rs m u st be water-soluble or water-dispersible. Molecular weights are >300 although the typical new chem ical polycationic polymer has a m o lecular weight in excess of 1000. EPA has been engaged in discussions with the Cationic Flocculant Producers Association in an attem p t to identify and develop a set of tests on representative polycationic polymers which could better define the limits of the category. General Testing Strategy To address ecotoxicity concerns, for polymers with % amine nitrogen <0.7% and >0.1%: base set acute aquatic toxicity testing in algae, daphnids, and fish, plus humic acid testing in fish (20 mg /L humic acid in dilution water and 10 m g /L) is recomme nded. All testing uses static me thod, nominal concentrations. For som e memb ers of the class, a test of sorbed chemical using a benthic organism ma y also be recomme nded. September, 1988; periodically revised.

113Category: Polynitroaromatics Environmental Toxicity This category includes all dinitroarom a tics and trinitroarom a tic compounds, for example, dinitrobenzenes, dinitroanilines, dinitrophenols, and dinitropyridines. Polynitroarom a tics probably act by uncoupling of oxidative phosphorylation (Doull et al 1980). It is assum e d that these compounds need to be absorbed to be toxic, therefore, compounds with MWs > 1000 will be excluded from this category. Acute toxicity for polynitroarom a tics which are liquids at room tem p erature is assum ed to be limited by the octanol/water partition coef fi cient (K ow ). Above a log K ow value of => 7.00 (based on test data for anilines reported Veith and Broderius 1987), polynitroarom a tics are not expected to show t oxic effects at saturation during 96-h exposures. Polynitroarom a tics which are solids at room tem p erature m a y show no toxicity at saturation at lower K ow values depending on the m e lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no toxicity will be observed at saturation. For solids, the no effects at saturation has to be determined on a case-by-case basis. There are no known K ow limits for chronic toxicity at this time, but it m a y not be m u ch above a log K ow = 10 for liquid polynitroarom a tics. Future testing will determine this K ow limit.
Haz a rd Concerns. The acute and chronic toxicity for several classes of polynitroarom a tics have been determined through SAR Analysis: dinitroanilines : fish 96-h LC50 (mM/L)= -0.027 -0.596 log K ow ; N=2; R2 =1.0 daphnid 48-h LC50 (mM/L)= -0.296 -0.558 log K ow

ow ; N=2; R2 =1.0 ; N=2; R2 =1.0 fish ChV (mM/L)= -0.91 -0.661 log K dinitrobenzenes : fish 96-h LC50 (mM/L)= -1.867 -0.333 log K ow ; N=2; R2 =1.0 daphnid 48-h LC50 (mM/L)= -0.325 -0.634 log K ow ; N=3; R2 =0.86 fish ChV (mM/L)= -3.0 -0.40 log K ow ; N=2; R2 =1.0 daphnid ChV (mM/L) = -0.7 -0.625 log K ow ; N=2; R2 =1.0 dinitrophenols : fish 96-h LC50 (mM/L)= -0.285 -0.559 log K ow ; N=4; R2 =0.96 daphnid 48-h LC50 (mM/L)= 0.083 -0.632 log K ow ; N=7; R2 =0.85 fish ChV (mM/L)= -1.78 -0.552 log K ow ; N=4; R2 =1.0 daphnid ChV (mM/L) = -0.465 -0.654 log K ow ; N=2; R2 =1.0 Polynitroarom a tics are known to be m o re toxic than predicted by the neutral organic SARs.
Mem b ers of this category exhibit toxicity rangi ng from low toxicity (i.e., > 100 m g /L) to high

ow and MW

. toxicity (i.e., < 1 m g /L) depending on their K

114Fate : Polynitroarom a tics are expected to be subject to rapid direct and indirect photolysis under environmentally realistic conditions.
Boundaries. : There are no known lower boundaries. The upper boundaries will be based on K ow and MW

. Acute toxicity expected with log K ow < 7.0; no effects at saturation during 96-h exposures when log K ow >= 7.0. Chronic toxicity has no known upper bound for log K ow , but it is probably near 10. MW will be < 1000. The environmental base set of tests will be requested fo r aquatic releases and the terrestrial base set of tests will be recom me nded f o r terrestrial exposures. Wh en the log K ow is >= 7.0, chronic toxicity testing with fish and daphnids will be recomme nded. General Testing Strategy . I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity tests for fish (40 CFR 797.1400) and daphnids (40 CFR 797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should equal the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. The algal toxicity testing (40 CFR 797.1050), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nominal-basis equal to the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. If there is no significant risk from the PMN after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Direct and Indirect Photolysis Screening Test (40 CFR 796.3765). If t1⁄2 < 2 days, go to Tier 3; if t1⁄2 > 2 days, go to Tier 4.

115Tier 3a. If t1⁄2 < 2 days and photolysis products are known and/or identified, then assess photolysis products for environmental hazards. Tier 3b. If t1⁄2 < 2 days and photolysis products are not known and/or identifiable, then prepare a stock solution of PMN using the sta ndard humic-containing solution described in the direct and indirect photolysis screening te st [40.796.3765 (b)(2) and (c)(2)], expose to sunlight for at least 6 half-lives (t1⁄2), and test photolysis products for toxicity with m o st sensitive species fr om environmental base set. For example, if the m o st sensitive species f r om the environmental base set has an EC50 value = 2.0 m g PMN/L (based on 100% active ingredients [AI]), then prepare a 5.0 m g PMN per liter stock solution based on 100% AI using the standard humiccontaining solution. This stock solution is exposed to sunlight for at least 6 half-lives to ensure that all of the PMN has been photolyzed, and then this stock solution is used to retest the m o st sensitive aquatic species to determine if the photolysis products of the PMN are m o re or less toxic that the PMN. Tier 4. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR 797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because Van Leeuwen et al ( 1990) have demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen); Daphnid chronic toxicity testing ( 40 CFR 797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; the highest treatment concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test because Van Leeuwen et al (1990) have demonstrated that the fish 7-d ELS toxicity test underestimated the chronic toxicity of anilines

116m easured by the fish 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180
II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay.
References. Doull J, Klaassen CD, and Amdur MO. 1980. Casarett and Doull's Toxicology. The Basic Science of Poisons. Second Ed. New York, NY: Macmillan Pub. Co., Inc. Van Leeuwen CJ, Adema DMM, and Hermens J. 1990. Quantitative structure-activity relationships for fish early life stag e toxicity. Aquatic Toxicology 16:321-334. Veith GD and Broderius SJ. 1987. Structure-toxi city relationships for industrial chemicals causing type (II) narcosis syndrome. In Kaiser KLE (ed), QSAR In Environmental Toxicology - II, p 385-391. Boston, MA: D. Reidel Publishing Com p any. May, 1991

117Category: Respirable, Poorly Soluble Particulates Health Only
Definition. This category includes a variety of inorganic, poorly soluble (as designated in ILSI 2000) particulates. Typically, they are oxides of various m e tals or nonmetals (i.e., silicon)
Boundaries. Potential f o r respirability--that is, if there are any particles 

### # 10 

### : in diameter in the m a terial being handled by workers. Summa rized below are currently available test data on five different poorly soluble particulates–s ilica, talc, titanium dioxide, PMN 96-175 (lithium ma nganese oxide), and carbon black. The suitability of one or m o re of these analogues for a particular PMN particulate m u st be determined on a case-by-case basis. Risk is to be assessed by the m a rgin of exposure m e thod for the reason stated in the next paragraph.
Haz a rd Concerns The category concerns discussed here are lim ited to effects on the lung as a result of inhaling the particles. Broadly, as shown in rat inhalation studies, these effects range from inflam ma tion to fibrosis to, potentially, cancer. Because it is still not known with certainty whether high lung burdens of poorly soluble particulates can lead to lung cancer in humans via m e chanism s similar to those of the rat, in the absence of mechanistic data to the contrary, it m u st be assum e d that the rat model can identify potential carcinogenic hazards to humans. Since the apparent responsiveness of the rat model at overload is dependent on coexistent chronic active inflamma tion and cell proliferation, at lower lung doses in which chronic active inflamma tion and cell proliferation are not present, no lung cancer hazard is anticipated (ILSI 2000).
Som e of the particulates m a y contain m e tals, for example, chrom i um, that m a y present other and mo re immi nent toxicities, depending on the bioavailability of the m e tal ions. Thus, the toxicities of the m e tal components of the particulates m u st also be assessed, and on a case-by-case basis. Lung Toxicity of Five Poorly Soluble Particulates
1. Fibrogenicity/Carcinogenicity of Crystalline Silica
Hum a ns
. Based on “sufficient evidence” for the carcinogenicity of inhaled crystalline silica from occupational sources, the International Agency for Research on Cancer (IARC, 1997) has classified crystalline silica as a Group 1 carcinogen in humans. According to IARC, studies of the following populations provided the least-confounded examinations of an association between silica exposure and cancer risk: gold m i ners, stone industry workers, granite shed and quarry workers, crushed stone industry workers, diatom aceous earth industry workers, refractory brick workers, pottery workers, and cohorts of registered silicotics. Not all of these studies demonstrated excess cancer risks; but, in view of the large number of epidemiological studies undertaken and the wide range of populations and exposure circumstances, som e nonuniformity of results would be expected. In som e studies, increasing risk gradients have been observed in relation to dose surrogates--cumulative exposure, duration of exposure, or the presence of radiographically defined silicosis--and, in one instance, to peak intensity exposure. For these reasons, the IARC W o rking Group

118concluded that overall, the epidemiological findings support increased lung cancer risks from inhaled crystalline silica resulting from occupational exposure. Animals

. IARC (1997) has concluded that there is “sufficient evidence” in experim e ntal animals for the carcinogenicity of crystalline silica. A number of studies ( rev.in : IARC, 1997; Woo et al. , 1988; Holland, 1990) have demonstrated that, in addition to silicosis/fibrosis, pulmonary tum o rs are induced in rats exposed to quartz (Mini-U-Sil; a comm on form of crystalline silica) by inhalation, single intrapleural, intraperitoneal, and/or intratracheal adm i nistration. In a 24- m onth inhalation study in rats, the lowest tested dose of respirable crystalline silica particles to induce lung tum o rs (Lowest Observed Adverse Effect Level, or LOAEL) w a s 0.74 mg/m 3

.


### K Note for Cases Using Silica as Primary Analogue: For LOAEL doses, the Agency considers a Margin of Exposure (MOE) of 1,000 or greater as representing a low order of toxicity for health endpoints for which a threshold dose is deemed appropriate. In this instance, exposures would have to be reduced to 0.0007 m g /m 3 to achieve a MOE of 1,000, a concentration that is practically impossible to achieve. Because the LOAEL of 0.74 m g /m 3 is based on test data on pure silica and because silica is considered to be a m u ch m o re potent lung toxicant than crystalline particulates containing silica, the Agency has adopted the NIOSH REL (Recommended Exposure Level) for silica, 0.05 mg/m 3 , as a NCEL1/ (New Chemical Exposure Li mit - see ht tp :// www.ep a.gov/oppt/newchems/ncelmain.htm for more information) concentration that w o uld adequately protect w o rkers from crystalline particulates containing silica. This NCEL replaces the former one based on OSHA Permissable Exposure Limit (PEL) for silica 0.1 mg/m 3

.

2. Fibrogenicity/Carcinogenicity of Talc
Hum a ns
. Epidemiology studies suggest an association between nonfibrous talc (a finely powdered hydrous m a gnesium silicate) and lung cancer risk. The OSHA PEL for talc is 20 m

ppcf (million particles per cubic foot), and the NIOSH-recomme nded 8-hr TWA concentration is 2 m g /m 3

. Animals

. In an NTP inhalation study (NTP TR 421, 1993), m a le and fem a le F344 rats were exposed to 0, 6, or 18 m g /m 3 talc for 113 and 122 weeks, respectively. There was clear evidence of the carcinogenicity of talc in fem a le rats based on the increased incidence of alveolar/bronchiolar adenomas and carcinomas of the lung in the 18-mg/m 3 group (LOAEL). The No Observed Adverse Effect Level (NOAEL) from this study is 6 mg/m 3

. The NCEL for analogous particulates would be 0.06 m g /m 3

.

3. Fibrogenicity/Carcinogenicity of Titanium Dioxide (TI)
Hum a ns
. According to IARC (ACGIH 1993), there is inadequate evidence for t he carcinogenicity of TI in humans. [There is limited evidence for the carcinogenicity of TI in experim e ntal animals.] Overall evaluation: TI is not classifiable as to its carcinogenicity to

119humans. The OSHA PEL’s for nuisance dust (in which TI is included) are 15 m g /m 3 total particulates and 5 m g /m 3 respirable fraction. The ACGIH TLV-TW A is 10 m g /m 3 of total dust containing no asbestos and <1% crystalline silica. The various literature case reports of lung toxicity in TI-exposed workers are generally inconclusive because of several factors--smoking; other conditions, such as tuberculosis; or incom p lete data on TI exposure histories. In one fairly com p rehensive cohort study, Chen and Fayerweather (1988, as summa rized in ACGIH 1993) analyzed lung cancer m o rtality and inci dence of chronic respiratory disease, chest x-ray abnorm a lity, and pulmonary fibrosis among 1,576 workers exposed to TI for at least 1 yr at two production facilities between 1935 and 1984. Of the 211 deaths, 14 were attributed to respiratory cancer and 11 to nonmalignant respiratory disease com p ared with 18.3 and 13.8 cases expected, respectively, based on US m o rtality data. Expected deaths based on com p any mo rtality data since 1957 were 16.6 from respiratory cancer and 8.3 from nonmalignant respiratory disease. The authors concluded that the increase in deaths from nonmalignant respiratory disease com p ared with com p any data was not statistically significant. They further concluded that there was no significant associati on between exposure to TI and the respiratory diseases studied. Animals

. There is limited evidence for the carcinogenicity of TI in experim e ntal animals. Twoyear inhalation studies in animals are summa rized below. (1) Lee et al. (1986, as cited in ACGIH 1993 and in USEPA 1983) exposed Charles River-CD rats to 0, 10, 50, or 250 m g /m 3 for 6 hr/day 5 days/wk for 2 yr. The mean respirable fractions were 93.7% or greater. Squamous cell carcinomas developed after exposure to the highest dose for the full 2 yr. The authors considered the carcinomas to be unique, experim e ntally induced tum o rs in rats and to be of questionable relevance to humans. Given the amount of dust in the rat lungs, the tum o rs were postulated to be the result of saturation of norm a l pulmonary clearance mechanism s. There were m i nute areas of lung fibrosis at the two higher exposure levels.

At 50 m g /m 3 , m a ssive accum u lations of dust-laden macrophages, foamy dust cells, and free particles were considered indicative of such an overload. At 10 m g /m 3 , the architecture of the air spaces rem a ined intact and there was no significant formation of scar tissue. The NOAEL is 10 mg/m 3

. (2) Heinrich et al. (1995, abstract only) exposedWi star rats to diesel engine exhaust, carbon black, or ultrafine TI for 2 yr. Particle exposur e concentrations were increased during the course of the experim e nt. The average particle concentration of TI was 10 m g /m 3

. Lung tum o r rates (not given) increased with increasing cum u lative particle exposure times, independent of the type of particle. (3) Trochim o wicz et al. (1988, abstract only) exposed Charles River-CD rats to 10, 50, or 250

120mg /m 3 TI for 6 hr/day, 5 days/wk for 104 wk. Microscopic findings included alveolar cell hyperplasia, dust deposition, and m i nute areas of collagen fiber deposition associated with cholesterol giant cell granulomas. The earliest indicator of TI exposure was alveolar cell hyperplasia. Lung tum o rs were only found in rats exposed to 250 m g /m 3

. The NOAEL from this study is 10 mg/m 3

. On the basis of the NOAEL’s from the above studies, the NCEL for analogous particulates would be 0.1 m g /m 3

. However, this would m a ke the NCEL for TI analogues identical to that for silica, a highly potent lung toxicant that IARC (1997) has classified as a Group 1 carcinogen in humans (see section 1, above). Therefore, it was decided to use the OSHA PEL for TI, which is 5 m g /m 3 (respirable fraction), as the NCEL for TI analogues.
4. Lung Toxicity of PMN 96-175, Lithium Manganese Oxide Animal Data Only

. Rats were exposed by inhalation to 0 (air controls), 1, 4, or 16 m g /m 3 of the PMN substance 6 hr/day, 5 days/wk for 90 days. At the highest concentration, rats developed inflamma tion of the lung and larynx. Similar results were seen in the 14-day range-finding study at concentrations ranging from 10 to 100 m g /m 3

. The NOAEL from this study is 4 mg/m 3

. The NCEL for analogous particulates would be 0.04 m g /m 3

.

5. Fibrogenicity/Carcinogenicity of Carbon Black Chronic inhalation of carbon black produced pulmonary inflamma tion, fibrosis, and lung tum o rs in rats (Nikula et al. 1995, Heinrich et al . 1995). These effects were observed at dust concentrations of 2.5, 6.6, and approxim a tely 10 m g /m 3 carbon black. The LOAEL from these studies is 2.5 mg/m 3

. The NCEL for analogous particulates would be 0.0025 m g /m 3 . [The OSHA PEL for carbon black is 3.5 m g /m 3 .]
General Testing Strategy A 90-day inhalation toxicity test (CFR 870.3465) in rats with special attention to histopathology (inflamma tion and cell proliferation) of the lung tissues and to various param e ters of the bronchoalveolar lavage fluid (BALF), e.g., m a rker enzym e activities, total protein content, total cell count, cell differential, and cell viability. It is not necessary to look at internal organs. It is recomme nded that a recovery period of 60 days be included to assess the progression or regression of any lesions. If the results of th e subchronic study indicate that the PMN particles have carcinogenic potential, a 2-year inhalation bioassay in rats m a y be warranted.

REFERENCES ACGIH. 1993. American Conference of Govern me ntal Industrial Hygienists: Threshold Lim it Values for Chemical Substances and Physi cal Agents and Biological Exposure Indices, 1993-

1211994. Cincinnati, Ohio: ACGIH. Heinrich U, Fuhst R, Rittinghausen S, Creutzenberg O, Bellmann B et al. 1995. Chronic inhalation exposure of W i star rats and two differe nt strains of m i ce to diesel engine exhaust, carbon black, and titanium dioxide. I nhal Toxicol 7:533-556. Abstract only. Holland LM. Reg. Toxicol. Pharmacol. 12 :224-237, 1990 IARC. 1997. International Agency for Research on Cancer. Monographs. Vol. 68, pp.41-336. ILSI. 2000. International Life Sciences Institute. Wo rkshop: The relevance of the rat lung response to particle overload for human risk assessm ent. Inhal Toxicol 12: 1-17. Nikula KJ, Snipes MB, Griffith W C , Henderson RF, Mauderly JL. 1995. Com p arative pulmonary toxicities and carcinogenicities of chronically inhaled diesel exhaust and carbon black in F344 rats. Fund Appl Toxicol 25:80-94. NTP. Toxicology and Carcinogenesis Studies of Talc in F334/N rats and B6C3F1 m i ce. National Toxicology Program, Technical Report No. 421, 1993. Trochim o wicz HJ et al. 1988. J A ppl Toxicol 8:383-435. Abstract only. USEPA. 1983. Status report for 8EHQ-1083-0497. Preliminary findings from a 2-yr rat inhalation study of titanium dioxide conducted by E. I. Du Pont de Nemours & Co., Inc. From Justine W e lch, Chief, Chemical Risk Indentifi cation Section, to Frank Kover, Chief, Chemical Screening Branch, Existing Chemicals Assessment Div., OPPT, USEPA.
W oo, Y.-T., Lai, D.Y., Arcos, J.C., and Argus, M.F.: Chemical Induction of Cancer, Vol. III C, Academic Press, p. 508, 1988. October, 2002

122Category: Rosin Environmental Toxicity This category includes rosin, abietic acid, abietinic acid, sylvic acid, their salts, and polymeric forms whose MW < 1000. The mode of toxic action of rosin is unknown. It is assum e d that these compounds need to be absorbed to be toxic, therefore, compounds with MW s > 1000 will be excluded from this category. It is also assum e d that these compounds need to be water soluble to be toxic, therefore, compounds with water solubilities (WS) < 0.001 m g /L (ppm) will also be excluded f r om this category.
Haz a rd Concerns. The acute toxicity for rosin towards fish has been measured to be between 0.410 to 0.700 m g /L by Leach and Thakore (1976 and 1978). Toxicity to aquatic invertebrates and green algae have no been reported. Based on these data, rosin presents a high concern for toxicity towards the aquatic environment.
Boundaries. The only lower boundary is water solubility which is set at 0.001 m g /L (ppm). The only upper boundary will be set at a MW > 1000 for stable compounds. The environmental base set of tests will be requested f o r aquatic releases and the terrestrial base set of tests will be recomme nded for terrestrial exposures. General Testing Strategy . The aquatic base set of environmental toxicity tests will be recom me nded f o r aquatic exposures. The acute toxicity tests for fish (CFR §797.1400) and daphnids (CFR §797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should equal the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility. The algal toxicity testing (CFR §797.1050), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nominal-basis equal to the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility. Fish chronic toxicity testing, i.e., fish early life stage (ELS) toxicity testing (CFR §797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test because Van Leeuwen et al

123(1990) have demonstrated that the 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen); Daphnid chronic toxicity testing (C FR §797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; the highest treatment concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test because Van Leeuwen et al (1990) have demonstrated that the fish 7-d ELS toxicity test underestimated the chronic toxicity of anilines measured by the fish 28-d ELS toxicity test by >5.3 times when the NOECs were com p ared (see Table VII in Van Leeuwen). The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test [§797.2800], the earthworm acute toxicity test [§795.150], and the soil m i crobial comm unity bioassay [795.3700]) will be recomme nded for terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whol e life cycle test [§797.2830], the plant uptake test [§797.2850], and the soil m i crobial comm unity bioassay.
References. Leach , J. M. and Thakore, A. N., 1976. Toxic constituent in mechanical pulping effluents. Tappi, 59:129. Leach , J. M. and Thakore, A. N., 1978. Compounds toxic to fish in pulp mill waste streams. Progr. W a ter Technol. (G.B.) 9:787. Van Leeuwen CJ, Adema DMM, and Hermens J. 1990. Quantitative structure-activity relationships for fish early life stag e toxicity. Aquatic Toxicology 16:321-334. January, 1994

124Category: Stilbene, derivatives of 4,4-bis(triaz i n-2-ylamino)-
Hum a n Health (case-by-case)
Definition. Any water soluble (sulfonated) derivativ e of 4,4-bis(triazin-2-ylamino) stilbene is considered to be a m emb er of this category.

Haz a rd Concerns. EPA previously identified hazard concerns for the possible developmental/reproductive toxicity of new chemicals falling into this stilbene, derivatives of 4,4-bis(triazin-2-ylamino)- category based on published test results for a m emb er of the category. EPA has reviewed test data developed by the Stilbene Wh itening Agent Task Force of the Ecological and Toxicological Association of Dyes and Organic Pigments Manufacturers (ETAD). These studies consisted of a range-finding and def i nitive 2-generation rat study (gavage) and range-finding and def i nitive developmental toxicity studies in rats and rabbits (gavage) for C.I. Fluorescent Brightener 220 (CAS No. 16470-24-9). Based on the results from these studies, EPA has concluded that available information does not support continued identification of stilbenes as a new chemical category presenting concerns f o r possible developmental/reproductive toxicity. EPA will continue to evaluate the potential health concerns f o r new chemical stilbenes that are notified but, with this change, will not apply a category understanding as regards potential developmental/reproductive toxicity.
References. Breslin, W J. A pilot prenatal developmental t oxicity study of C.I. Fluorescent Brightener 220 and C.I. Fluorescent Brightener 339 adm i nistered via oral gavage to rats. MPI Research Laboratory Study Identification 795-001, August 18, 1998a. Breslin, W J. A pilot prenatal developmental t oxicity study of C.I. Fluorescent Brightener 220 and C.I. Fluorescent Brightener 339 adm i nistered via oral gavage to New Zealand Wh ite rabbits. MPI Research Laboratory Study Identification 795-002, August 18, 1998b. Turck, PA. Prenatal developm ental toxicity study of C.I. Fluorescent Brightener 220 adm i nistered via oral gavage to rats. MP I Research Laboratory Study Identification 795-003, December 2, 1999.

125Turck, PA. Range-finding reproduction study of C.I. Fluorescent Brightener 220 adm i nistered via oral gavage to rats. MPI Research Laboratory Study Identification 795-005, June 8, 2000a. Turck, PA. Prenatal developmental toxicity study of C.I. Fluorescent Brightener 220 adm i nistered via oral gavage to New Zealand W h ite rabbits. MPI Research Laboratory Study Identification 795-004, January 27, 2000b. Turck, PA. Two generation reproduction and fertility study of C.I. Fluorescent Brightener 220 adm i nistered via oral gavage in rats. MP I Research Laboratory Study Identification No. 795- 006, August 24, 2001. Previous Category Statement References. Burg, AW, Rohovsky, MW & Kensler, CJ (1977). Current status of human safety and environmental aspects of fluorescent whitening agents used in detergents in the United States. Critical Review & Environmental Control, 7, 91-120. Gloxhuber, CH & Bloching, H (1978). Toxicologi c properties of fluorescent whitening agents. Clinical Toxicology, 13, (2), 171-203. Keplinger, ML, Fancher, OE, Lym a n, FL & Calandra, JC (1974). Toxicologic studies of four fluorescent whitening agents. Toxicology & Applied Pharmacology, 27, 494-506. Keplinger, ML, Lym a n, FL & Calandra, JC ( 1975). Three-generation reproduction studies with FWAs. In: Flourescent W h itening Agents. R. Anliker & G. Muller (Eds.). Stuttgart, Germany: Georg Thiem e Publishers. Kramer, JB (1992). Fluorescent whitening agents. In: The Handbook of Environmental Chemistry, 3, (part F), 351-366. O. Hutzinger (Ed.). Heidelberg, Germany: Springer-Verlag Berlin. Lorke, D (1975). Studies of embryo toxicity in rats & rabbits. In: Flourescent Wh itening Agents. R. Anliker & G. Muller (Eds.). Stuttgart, Germany: Georg Thiem e Publishers. Lym a n, FL, Schulze, J, Ganz, CR, Stensby, PS, Keplinger, ML & Calandra, JC (1975). Longterm toxicity of four fluorescent whitening agents. Food, Cosmetics & Toxicology, 13, 521-527. Poiger, T & Giger, W (1991). Determination of fluorescent whitening agents in sewage and sewage sludge by high perform a nce liquid chrom a tography. Reprint of a poster presented at the m eeting of the Swiss Chemical Society in Bern, Switzerland. October 18, 1991. EAWAG/ETH, CH-8600 Dubendorf, Switzerland. Zinkernagel, R (1975). Fluorescent whitening agents in the environment. In: Flourescent Wh itening Agents. R. Anliker & G. Muller (Eds.). Stuttgart, Germany: Georg Thiem e Publishers.
8E-CAP - 0024. Report to Ciba-Geigy Corporati on. Teratogenic study with FA-15 in Albino

126rabbits, May 23, 1972. Submitted to USEPA on October 9, 1992.
PB81-148819. Information Hazard Profiles on Potential Occupational Hazards. Vol. 2. Chemical Classes Fluorescent Wh itening Agent (FW A's ). National Institute f o r Occupational Safety and Hazard, Rockville, Maryland. December 1979. January, 1992; revised December, 1994; revised August, 2002.

127Category: Thiols Environmental Toxicity This category includes all thiols or m e rcaptans. It is assum e d that thiols have to be absorbed to be toxic, therefore, compounds with MWs > 1000 will be excluded from this category. Acute toxicity for thiols which are liquids at room tem p erature is known to be limited by the octanol/water partition coef fi cient (K ow ). Above a log K ow value of <6.5 (CLOGP), thiols show no effects at saturation during 96-h exposures. Th iols which are solids at room tem p erature m ay show no toxicity at saturation at lower K ow values depending on the m e lting point, i.e., the higher the m e lting point at a given K ow , the greater the likelihood that no toxicity will be observed at saturation. For solids, the no effects at saturation has to be determined on a case-by-case basis. There are no known K ow limits for chronic toxicity at this time, but it m a y not be m u ch above a log K ow of 8 to 9 f o r liquid thiols. Future testing will determine this K ow limit.
Haz a rd Concerns. The acute toxicity for thiols has been determined through SAR Analysis: fish 96-h LC50 (m illimoles/L) = -1.022 - 0.447 log K ow daphnid 48-h LC50 (millimoles/L) = -3.2 - 0.097 log K ow Effective concentrations for green algal 96-h EC50 should be assum e d to be similar to fish and daphnids. Thiols which are substituted with a carboxylic acid will be about 10 times less toxic than predicted by this SAR at pH 7. Use the K ow for the free acid.
Mem b ers of this category exhibit toxicity rangi ng from low toxicity (i.e., > 100 m g /L) to high

ow , MW and substitutions. toxicity (i.e., < 1 m g /L) depending on their K
Boundaries. There are no known lower boundaries. The upper boundaries will be based on K ow and MW

. Acute toxicity expected with log K ow <6.5; no effects at saturation during 96-h exposures when log K ow > 6.5. Chronic toxicity has no known upper bound for log K ow , but it is probably near 9. MW will be <1000. The environmental base set of tests will be requested for aquatic releases and the terrestrial base set of tests will be recomme nded f o r terrestrial exposures. Wh en the log K ow is > 6.5, chronic toxicity testing will be recomme nded. General Testing Strategy

I. Release to Aquatic Ecosystem s : Tier 1. The aquatic base set of environmental toxicity tests will be recomme nded f or aquatic exposures. The acute toxicity tests for fish (CFR §797.1400) and daphnids (CFR §797.1300) will be done using the flow-through m e thod with measured concentrations; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should equal the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit.

128The algal toxicity testing (CFR §797.1050), should be done with static m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with at least 0.300 m g /L EDTA as a final concentration; the highest treatm e nt concentration on a nominal-basis equal to the aqueous solubility limit; and solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit. If there is no significant risk from the PMN after the results of the environmental base set have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Aerobic Aquatic Biodegradation 40 CFR 796.3100 Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180 If there is no significant risk from the PMN after the results of the aerobic biodegradation have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 3. Tier 3. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (CFR §797.1600), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; m easured TOC of dilution water in the control; the highest treatm e nt concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d ELS stage toxicity test cannot be substituted for the 28-d ELS toxicity test. Daphnid chronic toxicity testing (C FR §797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; m easured TOC of dilution water in the control; the highest treatment concentration on a nominal-basis should be set at the aqueous solubility limit; solvent can be used to assist the PMN to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the PMN beyond its aqueous solubility limit; and the 7-d daphnid chronic toxicity test cannot be substituted for the 21-d toxicity test.
II. Release to Terrestrial Ecosystem s

129The terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded f or terrestrial exposures. Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay. December, 1994

130Category: Substituted Triaz i nes Environmental Toxicity This category includes substituted triazines which can be aromatic, partially aromatic (or partially saturated) and unsaturated. The nitrogens in the triazine ring m a y be symme trical or asymme trical. Substitutions on the carbons m a y include but not be limited to: aliphatic alcohols; ketones; benzene and substituted benzenes; aliphatic hydrocarbons, alkyenes and alkynes; free amines and substituted amines; cyclic aliphatic hydrocarbons; halogens; amides; cyanides; ethers; m e thoxy groups; sulfides; azido groups; and carboxylic acid esters. Substitutions on the nitrogens m a y include but not be limited to: fr ee amines and substituted amines; -N=CH; aliphatic hydrocarbons, alkyenes and alkynes; and benzene and substituted benzenes.
Haz a rd Concerns. Many m em b ers of this category are comme rcial herbicides which are used to control both aquatic plants and terrestrial plants. Their mode of toxic action is generally considered to be inhibition of photosynthesis. Ma ny m emb ers of this class are toxic to algae at < 1 m g /L and toxic to terrestrial vascular plants at < 1 m g /kg. Mem b ers of this group can also be highly toxic to fish and aquatic invertebrates. Toxicity is expected to be related to the octanol/water partition coef fi cient with respect to f i sh and aquatic invertebrates, but toxicity to plants m a y not be related to Kow when log Kow < 5. Wh en the log Kow is < 5, algae and terrestrial plants are expected to be the m o st sensitive species. As log Kow increases, species differences are expected to dim i nish. At this time there is no formalized SAR for this category fo r any species. Toxicity predictions will be m a de using either the closest analog or averaging data for the two closest analogs which bracket the chemical under question.

Boundaries. There are no known lower boundaries. The upper boundaries are based on Kow and MW

. Wh en the log Kow value is < 5 m g /L, the environmental base set of tests will be requested f o r aquatic releases and the terrestrial base set of tests will be recom me nded f or terrestrial exposures. Wh en the log Kow is between 5 and 8, only chronic toxicity testing will be recomme nded. Wh en the log Kow is > 8, no testing will be requested because no toxic effects at saturation will be expected. Generally, m emb ers of this category will have MWs of less than 1000. General Testing Strategy The aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures and the terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm acute toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded for terrestrial exposures. August, 1989

131Category: Triarylmethane Pigments/Dyes wi th Non-solubilizing Groups Hum a n Health Environmental Toxicity
Other Names: Triphenylm e thane Pigments/Dyes, Diphenylnaphthylme thane Pigments/Dyes
Definition. Structurally, triarylmethane pigments/dyes are derivatives of triphenylm e thane or diphenylnaphthylm e thane. In order to achieve the required spectral absorption properties that characterize these dyes, amine groups (prim a ry, secondary, or tertiary) or hydroxyl groups m u st be present on the aromatic ring positions para to the m e thane carbon. Amine substitutions are mo re prevalent than hydroxy substitutions (C.I. 42000-42175 for diamino derivatives, C.I. 42500-42800 for triam i no derivatives, C.I. 43800-43875 for hydroxy derivatives, and 43500- 43570 for aminohydroxy derivatives).

Haz a rd Concerns. There are oncogenicity concerns for the triarylmethane pigments/dyes based on analogy to Gentian Violet and C.I. Basic Red 9. In addition, there are developmental and reproductive toxicity concerns for these compounds based on analogy to Gentian Violet and Malachite Green. Ecotoxicity concerns are base d on QSAR predictions for delocalized cationic

132dyes. Cationic dyes are an established ecotoxicity category.
Boundaries. Pigments/Dyes included in this category are the di- and tri-amino substituted triphenylm e thane and diphenylnaphthyl-methane derivatives. Dyes substituted with solubilizing groups such as carboxylic acid, sulfonic acid, or halogens, are not included. Pigments that have essentially negligible water solubility (<1ppb) and therefore, little or no bioavailability, are also not included. General Testing Strategy The New Chemicals Program considers the following tests to be appropriate to address the potential for triarylmethane pigments/dyes to pose a significant risk. For Health -
1. Developmental toxicity study in two species of rodents by the oral route (40 CFR 798.4900).
2. Two-generation reproductive toxicity study in rodents by the oral route (40 CFR 798.4700).
3. Salmonellatyphim u rium /Am e s assay with the Chinese ham s ter liver S9 activation system (40 CFR 798.5265).
4. Invivo m ouse m i cronucleus assay i.p. (40 CFR 798.5395). Tests 3. and 4. would trigger a lifetime rodent bioassay if positive. For Environmental toxicity and fate - Prior to Tier 1, the following physical-chem i cal properties need to be established: Melting point (40 CFR 796.1300) or boiling point (40 CFR 796.1220), water solubility (40 CFR 796.1840), log K ow (40 CFR 796.1550, 796.1570 or 796.1720), and vapor pressure (40 CFR 796.1950). Tier 1. The fish, daphnid, and algal (40 CFR 797.1050) acute toxicity tests from the aquatic base set of environmental toxicity tests will be recomme nded for aquatic exposures. The acute toxicity tests for fish (CFR §797.1400) and daphnids (CFR §797.1300) will be done using the flow-through m e thod with measured concentrations, and effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations. If there is no significant risk from the PMN after the results of the fish and daphnid acute toxicity tests have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then go to Tier 2.

133Tier 2. Direct and Indirect Photolysis Screening Test (40 CFR 796.3765). If t1⁄2 < 2 days, go to Tier 3; if t1⁄2 > 2 days, then integrate the results into the risk assessment. If there is no significant risk from the PMN, then no further testing is recomme nded. However, if there rem a ins a significant risk, then go to Tier 4. Tier 3a. If t1⁄2 < 2 days and photolysis products are known and/or identified, then assess photolysis products for environmental risk. If there is no significant risk from the photolysis products from the PMN, then no further testing is recomme nded. However, if there rem a ins a significant risk, then go to Tier 4. Tier 3b. If t1⁄2 < 2 days and photolysis products are not known and/or identifiable, then prepare a stock solution of PMN using the sta ndard humic-containing solution described in the direct and indirect photolysis screening te st [40.796.3765 (b)(2) and (c)(2)], expose to sunlight for at least 6 half-lives (t1⁄2), and test photolysis products for toxicity with m o st sensitive species fr om environmental base set. For example, if the m o st sensitive species f r om the environmental base set has an EC50 value = 2.0 m g PMN/L (based on 100% active ingredients [AI]), then prepare a 5.0 m g PMN per liter stock solution based on 100% AI using the standard humiccontaining solution. This stock solution is exposed to sunlight for at least 6 half-lives to ensure that all of the PMN has been photolyzed, and then this stock solution is used to retest the m o st sensitive aquatic species to determine if the photolysis products of the PMN are m o re or less toxic that the PMN. Integrate these toxicity results into the risk assessment. If there is no significant risk from the PMN, then no further testing is recomme nded. However, if there rem a ins a significant risk, then go to Tier 4. Tier 4. Test for aerobic biodegradability according to any one of the following test guidelines (listed in order of preference): Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180 Integrate the results f o r aerobic biodegradability into the risk assessment. If there is no significant risk from the PMN, then no further testing is recomme nded. However, if there rem a ins a significant risk, then do chronic toxicity testing for fish and daphnids: Fish chronic toxicity testing, i.e., fish early life stage (ELS) toxicity testing (CFR §797.1600), with flow-through m e thods; m easured concentrations; effective concentrations

134based on 100% active ingredients (AI) and mean measured concentrations; and statistical analysis of effective concentrations at days 7, 14, 21, and 28. Daphnid chronic toxicity testing (C FR §797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% active ingredients (AI) and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21.For Terrestrial ecosystemsThe terrestrial base set of environmental toxicity tests (i.e., the early seeding growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded f or terrestrial exposures. Chronic toxicity testing fo r terrestrial organism s include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay.
References: American Dye Manufacturers Institute, Inc. (ADMI), 1974, "Dyes and the Environment: Reports on Selected Dyes and Their Effects," Vol. II, ADMI, New York. Au W, Pathak S, Colie CJ, Hsu TC. 1978. Cytogene tic toxicity of Gentian Violet and Crystal Violet on m amma lian cells invitro

. Mutation Research 58:269-276.
Au W , Butler MA, Bloom SE, Matney TS. 1979. Further study of the genetic toxicity of Gentian Violet. Mutation Research 66:103-112. Auer, C. M., Nabholz, J. V. and Baetcke, K. P., 1990, "Mode of Action and the Assessment of Chemical Hazards in the Presence of Limited Data: Use of Structure-Activity Relationships (SAR) under TSCA, Section 5," Environmental Health Perspectives , Vol. 87, pp. 183-197. Kier LD, Brusick DJ, Auletta AE. 1986. The Salmonella typhim u rium /mam ma lian m i crosomal assay. A report of the U.S. Environmental Protection Agency Gene-Tox Program. Mutation Research168:69-240. Kirk-Othm e r, Encyclopedia of Chemical Technology , 3rd edition, vol. 23, pages 399-412. Little, L. W

. and Lam b J. C., III, 1972. Acute Toxicity of 46 Selected Dyes to the Fathead Minnow, Pim e phales promelas ,Final Report to the American Dye Manufacturers Institute,Inc., UNC W a stewater Research Center, Departm e nt of Environmental Sciences and Engineering, School of Public Health, University of North Carolina, Chapel Hill, NC. Littlefield NA, Blackwell B-N, Hewitt CC, Gaylor DW. 1985. Chronic toxicity and carcinogenicity studies of Gentian Violet inmi ce. Fundam e ntal and Applied Toxicology5:902- 912.

135Mortelm a ns K, Haworth S, Lawlor T. 1986. Salmonellamu tagenicity tests: II. Results from the testing of 270 chemicals. Environmental Mutagenesis 8(7):1-119. Nabholz, J. V., 1990. The OTS PMN ECOTOX Data Base: a Confidential Business Information (CBI) Collection of Environmental Toxicity Da ta from New Chemical Submissions Under Sec. 5

. Unpublished, Environmental Effects Branch, Health and Environmental Review Division (TS-796), U. S. Environmental Protection Agency, W a shington, DC. NCTR Technical Report for Experim e nt Num b ers 305,354,355. Three-generation reproduction and toxicity studies of Gentian Violet in Fischer 344 Rats. National Center for Toxicological Research. Jefferson, Arkansas. Sept. 1988. NCTR Technical Report for Experim e nt Num b er 355. Developmental toxicity study of Gentian Violet in Fischer 344 Rats. National Center fo r Toxicological Research. Jefferson, Arkansas. Sept. 1988. NTP. 1985. National Toxicology Program. C.I. Basic Red 9 monochloride. NTP TR-285. Sigman, C. C., Helms, C. T., Papa, P. A., Atki nson, D. L., Doeltz, M. K. and W i nship-Ball, A., Jan. 1983. Anthraquinone Dyes and Related Chem icals: Review and Assessment of Potential Environmental and Health Aspects . Final Report to the Dyes Environmental and Toxicology Organization, Inc., SRI International, Menlo Park, CA. Sokolowska-Pituchowa J, Kowalczkowa J, Kus J, Piotrowski J, Sawicki B. 1965. Teratogenic effect of Malachite Green in experi me ntal animals. Folia Biologica 13:311-315. Tonogai, Y., Ito, Y., Iwaida, M., Tati, M., Ose, Y. and Sato, T., 1979. Studies on the Toxicity of Coal-Tar Dyes. II. Examination of the Biological Reaction of Coal-Tar Dyes to Vital Body. The Journal of Toxicological Sciences , Vol. 4, pp. 211-219. July, 1994.

136Category: Vinyl Esters Hum a n Health Environmental Toxicity (See “Esters”)
Definition: A carboxylic acid ester with at least one vinyl group (CH 2 =CH-) attached to an organic acid radical (RCOO-). A sim p le vinyl ester is vinyl acetate:

CH 3 COOCH=CH 2

Note: Certain carboxylic acid m o ieties themselves m a y exert toxicity such that there are concerns for effects in addition to those identified for the vinyl ester class.
Haz a rd Concerns: Oncogenicitybased on data from two bioassays: a 2-yr drinking water study of vinyl acetate in rats [significantly increas ed incidences of adenocarcinomas of the uterus and com b ined C-cell adenomas and carcinomas in high-dose (2,500 m g /l) fem a le rats] and a chronic inhalation study of vinyl acetate in rats and m i ce (laryngeal/nasal tum o rs in rats, bronchiolar/alveolar adenomas in lungs of m i ce)

. There are supporting data from 27-m o and 81- wk inhalation studies of acetaldehyde in rats and ham s ters, respectively. Furthermore, mu tagenicity data on these analogues support a cancer concern. Neurotoxicitybased on data on an analogous PMN compound in rats plus suggestive data on vinyl acetate. Reproductive toxicitybased on a two-generation study of vinyl acetate in rats. Environmental toxicity (see "Esters" category).
Boundaries: Other than a requirem e nt for a vinyl group and an acid group, none. General Testing Strategy (1) Up-front glove permeation study if there is a risk of any toxicity through dermal exposure. (2) Hydrolysis test (both acid- and enzym e -catalyzed) to determine the rate at which acetaldehyde, a potentially toxic m e tabolite, is released. [The requirem e nt to measure acetaldehyde release is based on the assum p tionthat acetaldehyde is the presumed "ultimate carcinogen" of vinyl esters. This requirem e nt will be revisited as m o re decisive data becom e available. The hydrolysis data should be helpful in determining the m o st appropriate route of adm i nistration in the f o llowing tests.] (3) A 90-day neurotoxicity test in rats that includes a functional observational battery, mo tor activity tests, and neuropathology examinations. Also to be included, to address reproductive toxicity concerns, are the following adjuncts to the subchronic test:

137(a) W e ights of the testes, epididymides (total and cauda), pituitary, sem i nal vesicles (with coagulating glands), prostate, ovary, and uterus are to be recorded at the time of sacrifice. (b) Histopathology of the testes is to be done on the m a les at the time of sacrifice. Particular attention is to be directed toward achieving satisfactory quality f r om fi xation and embedding, and preparations are to follow the recomme ndations of Russell et al. (1990). Histologic analyses are to include evaluations of the sperm a togenic cycle; i.e., the presence and integrity of the 14 cell states. These evaluations would follow the guidance provided by Russell et al. (4) A standard developmental toxicity study in rabbits and rats. (5) A 2-yr bioassay in rats and m i ce to address cancer concerns. (6) Environmental toxicity testing: see "Esters" category.

References.

Russell LD, Ettlin RA, Sinha Hikim AP, Cl egg ED. 1990. Histological and histopathological evaluation of the testis. Cache River Press, Clearwater, FL. August, 1992

138Category: Vinyl Sulfones Hum a n Health Environmental Toxicity
Definition. Any m o lecular structure with a vinyl sulfone group is considered to be a m emb er of the class:
O 5 -S-CH=CH 2

5 O In addition the following is an example of a functional group that generates a vinyl sulfone under certain conditions. 

### $ -Sulfatoethyl-sulfonyl groups are typical vinyl sulfone precursors. Structures bearing this group are also m emb ers of the class:
O 5

- -S-CH 2 -CH 2 -OSO 3

5 O Typically, the new chemical of concern is a fiber-reactive dye bearing one or m o re vinyl sulfones, or vinyl sulfone precursors. Occupati onal exposure to workers via inhalation/ingestion of the powdered dye m a y pose a potential health risk. Under the conditions in a dye bath a vinyl sulfone precursor-containing dye generates the vinyl sulfone. In this scenario the only potential risk is to those who drink contaminated drinki ng water. However, following covalent binding of vinyl sulfone to textile fibers, survival of unbound vinyl sulfone substituents in the dye bath is low (< 10%). The m a jority of unbound vinyl sulfone is hydrolyzed to 

### $ -hydroxyethylsulfone. Unless releases to water are extremely high, vinyl sulfones are not expected to pose a significant risk to human health. Presently, there are no human health concerns for 

### $ -hydroxyethylsulfone.
Haz a rd Concerns. For those who inhale or ingest a vinyl sulfone, there is an oncogenicity concern and m u tagenicity concerns based on the potent m u tagenicity of vinyl sulfone (VS) and me thylvinyl sulfone (MVS). VS and MVS are m u tagenic in the L5178Y TK +/

- m ouse lymphom a gene m u tation assay invitro

. Evaluation of small colonies indicates that genotoxicity is due to a clastogenic mechanism

. This is confirm e d by evaluating the lymphoma cells for chrom o som e aberrations and m i cronuclei. MVS also induces effects upon the spindle apparatus in Chinese ham s ter lung cells in vitro , indicating an aneugenic (aneuploidy-inducing) activity. A directacting Michael addition-type reaction m a y be the mechanism of action. Although MVS and divinyl sulfone (DVS) are both reported as negative invivo in the mouse m i cronucleus assay (inconclusive, only m a les tested), and in the dominant lethal assay, the Agency has determined that these negatives are not sufficient to re m ove concern for vinyl sulfone-containing new chemicals as potential m u tagens and carcinogens. There are ecotoxicity concerns for VS only, based on concerns for electrophiles.

139Boundaries. There are at present no boundary conditions, related to health effects, for structures containing vinyl sulfones. Nearly all new chem icals in the category have been water-soluble, fiber-reactive dyes with m o lecular weights <1,000. The boundary conditions for ecotoxicity effects are m o lecular weights < 1000 and log K ow < 8. General Testing Strategy The New Chemicals Program considers the following tests to be appropriate to address health and ecotoxicity concerns: 1. Mouse lymphoma assay with evaluation of small colonies (40 CFR 798.5300). The test would trigger a lifetime rodent bioassay if positive. 2. Base-set ecotoxicity testing to incl ude fish (40 CFR 797.1400), daphnids (40 CFR 797.1300) and algae (40 CFR 797.1050). The acute toxicity tests for fish and daphnids will be done using the flow-through m e thod with measured concentrations, and effective concentrations will be based on 100% active ingredients (AI) and mean m easured concentrations. If there is insufficient knowledge about the water solubility of the dye, then it should also be m e asured (40 CFR 796.1840 or 796.1860). If there is no significant risk from the PMN after the results of the fish and daphnid acute toxicity and algal toxicity tests have been integrated into the risk assessment, then no further testing is recomme nded. However, if there is a significant risk, then do environmental fate testing as outlined in 3. 3. Environmental f a te testing f o r releases to water. Tier 1. Direct and Indirect Photolysis Screening Test (40 CFR 796.3765). If t1⁄2 < 2 days, go to Tier 2; if t1⁄2 > 2 days, go to Tier 3. Tier 2a. If t1⁄2 < 2 days and photolysis products are known and/or identified, then assess photolysis products for environmental hazards. Tier 2b. If t1⁄2 < 2 days and photolysis products are not known and/or identifiable, then prepare a stock solution of the PMN chemical using the standard humic-containing solution described in the direct and indirect photol ysis screening test [40 CFR 796.3765 (b)(2) and (c)(2)], expose to sunlight for at least 6 half-lives (t1⁄2), and test photolysis products for toxicity with the m o st sensitive species f r om the environmental base set.

140Tier 3. Test for aerobic biodegradability according to any one of the following test guidelines: Modified Sturm Test 40 CFR 796.3260 Closed Bottle Test 40 CFR 796.3200 Modified OECD Screening Test 40 CFR 796.3240 Modified MITI Test (I) 40 CFR 796.3220 Modified AFNOR Test 40 CFR 796.3180 In addition, if appropriate, physical/chem i cal properties including: Log K ow (40 CFR 796.1550, 796.1570, or 796.1720) Vapor pressure (40 CFR 796.1950) Boiling point (40 CFR 796.1220) Melting point range (40 CFR 796.1300) If the PMN chemical passes the aerobic biodegradability test according to the criteria set forth in the guidelines, no further testing m a y be recomme nded. A new risk assessment is conducted to determine if chronic ecotoxicity testing is warranted. 4. Fish chronic toxicity testing, i.e., fish ear ly life stage (ELS) toxicity testing (40 CFR 797.1600), with flow-through m e thods; measured concentrations; effective concentrations based on 100% AI and mean measured concentrations; and statistical analysis of effective concentrations at days 7, 14, 21, and 28. Daphnid chronic toxicity testing ( 40 CFR 797.1330), with flow-through m e thods; m easured concentrations; effective concentrations based on 100% AI and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21. 5. Ecotoxicity testing for release to terrestrial ecosystems. The terrestrial base set of environmental toxicity tests (i.e., the early seedling growth test, the earthworm toxicity test and the soil m i crobial comm unity bioassay) will be recomme nded f or terrestrial exposures. Chronic toxicity testing fo r terrestrial organism s include: the plant whole life cycle test, the plant uptake test, and the soil m i crobial comm unity bioassay.

References: Dearfield, KL, K Harrington-Brock, CL Doe rr, JR Rabinowitz, and MM Moore (1991). Genotoxicity in mouse lymphoma cells of chemicals capable of Michael addition. Mutagenesis 6: 519-525.

141Heyna, J (1963). Reactive dyes containing vinylsulfonyl groups. Angew . Chem. Internat. Edit. 2(1): 20-23. Shelby, MD, GA Gutierrez-Espeleta, W M Generoso, and AF McFee (1991). Mouse dominant lethal and bone m a rrow m i cronucleus studies on me thyl vinyl sulfone and divinyl sulfone. Mutation Research 250: 431-437.
Wa rr, TJ, JM Parry, RD Callander, and J Ashby (1990). Methyl vinyl sulfone: A new class of Michael-type genotoxin. Mutation Research 245: 191-199. September, 1988; revised June, 1994

142Category: Soluble complexes of Z i nc Environmental Toxicity
Definition. This category includes all organic and inorganic soluble com p lexes of zinc, for example, zincates, organozincs, such as, dim e thylzinc. Not included in this category are zinccom p lexed acid dyes and strong ion pairs between zinc and anionic surfactants. There are no toxicity data for soluble com p lexes of zinc, therefore, the toxicity data for the free Zn ++ ion will be used to predict aquatic toxicity.
Haz a rd Concerns. Zinc produces acute toxicity to freshwater aquatic organisms over a range of concentrations from 90 to 58,100 ug/L and produces chronic toxicity over a range from 47 to 852 ug/L. The acute to chronic ratio (ACR) f o r Zn has been set at 3 in the water quality criteria (WQC) document. Zinc concentrations from 30 to 21,600 ug/L have been shown to reduce the growth of various aquatic plants and algae appear to be the m o st sensitive group. Bioconcentration factors (as logarithm s ) for fres hwater fish ranged from 1.7 to 2.6, and from 2.0 to 3.1 for freshwater invertebrates. Zinc is an essential nutrient trace element which can be toxic at higher concentrations. Wh ile acute toxicity is affected by hardness, chronic toxicity is not affected. The freshwater criteria at an average hardness of 100 m g /L are 0.120 ug/L for acute exposures and 0.110 ug/L for chronic exposures; the saltwater criteria are 0.095 ug/L for acute exposures and 0.086 ug/L for chronic exposures. These criteria are based on toxicity information for the following Zn salts: sulfate, chloride, phosphate, and nitrate. General Testing Strategy To address ecotoxicity concerns, base set acute aquatic toxicity testing (algae: static m e thod, daphnid and fish: flow-through m e thod, all measured concentrations). April, 1990

143Category: Zi rconium Compounds Environmental Toxicity
Definition. This category includes inorganic salts of zirconium (Zr), com p lexes between Zr and organic acids, and organoZr compounds, i.e., Zr covalently-bonded with carbon. For example, som e inorganic Zr salts include: Zr sulfate, Zr oxychloride, and Zr tetrachloride. Not included in this category are dyes com p lexed with Zr.
Haz a rd Concerns. Soluble salts of Zr are known to be moderately toxic to green algae and fish based on exposures in soft water and in term s of m g Zr/L. Toxicity information are only available for Zr sulfate, Zr tetrachloride, and Zr oxychloride. The toxicity profile for Zr based on available toxicity data, m g Zr/L (ppm Zr), and moderate hardness (i.e., 150.0 m g /L as CaCO 3 ) is: fish 96-h LC50 = 58.0 (n=3) green algal 96-h EC50 = 2.6 Zirconium is m o re toxic in soft water than hard water. Acute toxicity to fish have been shown to increase 13 tim es as hardness decreases from 400.0 to 20 m g /L.
Boundaries. The toxicity of Zr compounds depends on the their physical/chem i cal properties and the hardness of receiving waters. The toxicity of Zr salts and Zr com p lexes with organic acids are expected to be related to their water solubility and MW

. The toxicity of organoZr com pounds are also expected to be related to their octanol/water partition coefficient (Kow). The m o st important property determ ining the toxicity of Zr compounds is water solubility. Wa ter solubility cannot be estimated accurately and has to be measured. The water solubility of organoZr compounds is expected to decrease as Kow increases. There is no lower bound for Kow and the upper bound cannot be determined at this time since the Kow fragm e nt-constant for Zr is not known. In addition to solubility, MW is also an important boundary. Compounds with MWs > 1000 are not expected to be absorbed by aquatic organisms even if they are water soluble. Therefore, only Zr compounds with MWs < 1000 are expected to be toxic. General Testing Strategy
I. Release to Aquatic Ecosystem s Tier 1. The aquatic base set of environmental toxicity tests will be recom me nded f o r aquatic exposures. The acute toxicity tests for fish (40 CFR §797.1400) and daphnids (40 CFR §797.1300) will be done using the flow-through m e thod; effective concentrations will be based on 100% active ingredients (AI) and mean measured concentrations; the total organic carbon (TOC) concentration of dilution water in the control m u st be less than 2.0 m g TOC/L; TOC mu st be measured in the control just prior to the start of the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; solvent can be used to assist the compound to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water

144solubility of the compound beyond its aqueous solubility limit; and hardness of dilution water

3 . If toxicity mitigation testing is done with humic acid, then the static m e thod with nominal concentrations will be recomme nded. has to be less than 180.0 m g /L as CaCO
The algal toxicity testing (40 CFR §797.1050), should be done with the static m e thod; effective concentrations based on 100% AI and m ean measured concentrations; statistical analysis of effective concentrations at 24, 48, 72, and 96 hours; test m e dium with no m o re than 0.300 m g /L EDTA as a final concentration; the TOC of the test/growth m e dium should be less than 2.0 m g TOC/L; TOC should be measured just prior to the start of the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; and solvent can be used to assist the compound to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the compound beyond its aqueous solubility limit. If toxicity mitigation testing is done with humic acid, then nominal concentrations will be recomme nded. If there is no significant risk from the Zr compound after the results of the environmental base set have been integrated into the risk assessment, then no f u rther testing will be recomm e nded. However, if there is a significant risk, then go to Tier 2. Tier 2. Fish chronic toxicity testing, i.e., fi sh early life stage (ELS) toxicity testing (40 CFR §797.1600), with the flow-through m e thod; eff ective concentrations based on 100% AI and m ean measured concentrations; statistical analysis of effective concentrations at days 7, 14, 21, and 28; the TOC of dilution water in the control should be less than 2.0 m g TOC/L; TOC should be m easured in the controls just prior to and during the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; solvent can be used to assist the compound to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the compound beyond its aqueous solubility limit; and hardness of dilution water has to be less than 180.0 m g /L as CaCO 3 . Daphnid chronic toxicity testing (40 CFR §797.1330), with the flow-through m e thod; effective concentrations based on 100% AI and mean measured concentrations; statistical analysis of effective concentrations at days 7, 14, and 21; the TOC of dilution water in the control should not exceed 2.0 m g TOC/L; TOC m u st be m e asured in the controls just prior to and during the test; the highest treatm e nt concentration on a nominal-basis should not exceed the aqueous solubility limit of the tested compound; solvent can be used to assist the compound to reach its aqueous solubility limit quicker, but cannot be used to artificially enhance the water solubility of the compound beyond its aqueous solubility limit; and hardness of dilution water has to be less than 180.0 m g /L as CaCO 3 . II. Release to Terrestrial Ecosystem s : The terrestrial base set of environmental toxicity tests will be recomme nded for terrestrial exposures. The terrestrial base set includes: the early seeding growth test (40 CFR 797.2800), the earthworm toxicity test (40 CFR.795.150), the soil mi crobial comm unity bioassay (40 CFR 797.3700), and the avian acute oral toxicity test (40 CFR 797.2175). Chronic toxicity testing for terrestrial organisms include: the plant whole life cycle test (40 CFR 797.xxxx), the plant uptake test (40 CFR 797.2850), and the avian reproduction test (40 CFR 797.2130 for bobwhite quail or 40 CFR 797.2150 for m a llard duck). June, 1992
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