PB85-22 7049



# Guidelines for Deriving Numerical National Water Quality Criteria for the Protection Of Aquatic Organisms and Their Uses

by Charles E. Stephen, Donald I. Mount, David J. Hansen, John R. Gentile, Gary A. Chapman, and William A. Brungs

Office of Research and Development Environmental Research Laboratories Duluth, Minnesota Narragansett, Rhode Island Corvallis, Oregon

## Notices
This document has been reviewed in accordance with U.S. Environmental Protection Agency policy and approved for publication. Mention of trade names or commercial pr oducts does not constitute endorsement or recommendation for use. This document is available th e public to through the National Technical Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161. 

## Special Note
This December 2010 electronic version of the 1985 Guid elines serves to meet the requirements of Section 508 of the Rehabilitation Act. While converting the 19 85 Guidelines to a 508-compliant version, EPA updated the taxonomic nomenclature in the tables of Appe ndix 1 to reflect changes that occurred since the table were originally produced in 1985. The numbe rs included for Phylum, Class and Family represent those currently in use from the Integrated Taxonomic Information System, or ITIS, and reflect what is referred to in ITIS as Taxonomic Serial Numbers. ITIS replaced the National Oceanographic Data Center (NODC) taxonomic coding system which was used to cr eate the original taxonomic tables included in the 1985 Guidelines document (NODC, Third Addition - see Introduction). For more information on the NODC taxonomic codes, see http://www.nodc.noaa.gov/General/C DR-detdesc/taxonomic-v8.html

. The code numbers included in the reference column of the tables have not been updated from the 1985 version. These code numbers are associated with the old NODC taxonomic referencing system and are simply replicated here for historical pur poses. Footnotes may or may not still apply. EPA is working on a more comprehensive update to the 1985 Guidelines, including new taxonomic tables which better reflect the large number of aquatic anim al species known to be propagating in U.S. waters.



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## Table of Contents Notices ___________________________________________________________________ ii Table of Contents ___________________________________________________________iii Executive Summary _________________________________________________________ iv Figure 1 ___________________________________________________________________ v Introduction________________________________________________________________ 1 I. Definition of Material of Concern _______________________________________ 9 II. Collection of Data___________________________________________________ 11 III. Required data ______________________________________________________ 11 IV. Final Acute Value ___________________________________________________ 14 V. Final Acute Equation ________________________________________________ 17 VI. Final Chronic Value _________________________________________________ 19 VII. Final Chronic Equation_______________________________________________ 22 VIII. Final Plant Value____________________________________________________ 25 IX. Final Residue Value _________________________________________________ 25 X. Other Data_________________________________________________________ 28 XI. Criterion __________________________________________________________ 28 XII. Final Review _______________________________________________________ 29 References________________________________________________________________ 31 Appendix 1. Resident North American Species of Aquatic Animals Used in Toxicity and Bioconcentation Tests_______________________________________________________ 33 Introduction_____________________________________________________________ 33 Freshwater Species Table __________________________________________________ 34 Footnotes for Freshwater Species ____________________________________________ 42 References for Freshwater Species ___________________________________________ 43 Saltwater Species Table ___________________________________________________ 45 Footnotes for Saltwater Species _____________________________________________ 51 References for Saltwater Species ____________________________________________ 51 Appendix 2. Example Calculation of Final Acut e Value, Computer Program, and Printouts 53 A. Example Calculation_________________________________________________ 53 B. Example Computer Program in BASI C Language for Calculating the FAV______ 53 C. Example Printouts from Program _______________________________________ 54

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## Executive Summary
Derivation of numerical na tional water quality criteria for the protection of aquatic organism and their uses is a complex process (Figure 1) that uses information from many areas of aquatic toxicology. After a decision is made that a nationa l criterion is needed for a particular material, all available information concerning toxicity t o, and bioaccumulation by, aquatic organisms is collected, reviewed for acceptability, and sorted. If enough ac ceptable data on acute toxicity to aquatic animals are available, they are used to estimate the highest one-hour average concentration that should not result in unacceptabl e effects on aquatic organisms and their uses. If justified, this concentration is made a functi on of a water quality characteristic such as pH, salinity, or hardness. Similarly, data on the chronic toxicity of the material to aquatic animals are used to estimate the highest four-daily average concentration that should not cause unacceptable toxicity during a long-term exposure. If appropriate, this concentra tion is also related to a water quality characteristic. Data on toxicity to aquatic plants are examined to determine whether plants are likely to be unacceptably affected by concentrations that shou ld not cause unacceptable effects on animals. Data on bioaccumulation by aquatic organisms are used to determine if residues might subject edible species to restrictions by the U.S. Food and Drug Administration or if such residues might harm some wildlife consumers of aquatic life. Al l other available data are examined for adverse effects that might be biologically important. If a thorough review of the pe rtinent information indicates that enough acceptable data are available, numerical national wate r quality criteria are derived for fresh water or salt water or both to protect aquatic organisms and their uses from unacceptable effects due to exposures to high concentrations for short peri ods of time, lower concentrations for longer periods of time, and combinations of the two.

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## Figure 1 Derivation of Numerical National Water Quality Crtieri a for the Protection of A quatic Organisms and Their Uses

Acute Toxicity to

Animals

Bioaccumulation

Other Data

Chronic Toxicity to

Animals

Toxicity to

Plants Final Acute Value

Final Residue

Value

Lowest Biologically Important

Value Final Chronic Value

Final Plant

Value Criterion Maximum Concentration

Criterion Continuous Concentration Review for Completeness

of Data and Appropriateness of Results

National Criterion Collect and

Review

Data



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## Introduction Of the several possible forms of criteria, th e numerical form is the most common, but the narrative (e.g., pollutants must not be present in harmful con centrations) and operational (e.g., concentrations of pollutants must not exceed one-t enth of the 96-hr LC50) forms can be used if numerical criteria are not possible or desirable. If it were feasib le, a freshwater (or saltwater) numerical aquatic life national criterion * 

### for a material should be determined by conducting field tests on a wide variety of unpollute d bodies of fresh (or salt) water. It would be necessary to add various amounts of the material to each body of water in order to determine the highest concentration that would not cause any unaccepta ble long-term or short-term effect on the aquatic organisms or their uses. The lowest of these highest concentrations would become the freshwater (or saltwater) national aquatic life wa ter quality criterion for th at material, unless one or more of the lowest concentrations were judge d to be outliers. Because it is not feasible to determine national criteria by conducting such fi eld tests, these Guidelines for Deriving Numerical National Water Quality Criteria for th e Protection of Aquatic Organisms and Their Uses (hereafter referred to as the National Gu idelines) describe an objective, internally consistent, appropriate, and feas ible way of deriving national cr iteria, which are intended to provide the same level of protect ion as the infeasible field tes ting approach described above. Because aquatic ecosystems can tolerate some st ress and occasional advers e effects, protection of all species at all times and places is not deemed necessary. If acceptable data are available for a large number of appropriate taxa from an appropriate variety of taxonomic and functional groups, a reasonable level of protec tion will probably be provided if all except a small fraction of the taxa are protected, unless a commercially or recreationally important species is very sensitive. The small fraction is set at 0.05 because other fractions resulted in criteria that seemed too high or too low in comparison with the sets of data from which they were calculated. Use of 0.05 to calculate a Final Acute Valu e does not imply that this per centage of adversely affected taxa should be used to decide in a field situation whether a criteri on is too high or too low or just right. Determining the validity of a criterion deri ved for a particular body of water, possibly by modification of a national criteri on to reflect local conditions 1 , 2 , 3 

### , should be based on an operation definition of "protection of aquatic orga nisms and their uses" that takes into account the practicalities of field m onitoring programs and the concer ns of the public. Monitoring programs should contain sampling points at e nough times and places that all unacceptable changes, whether caused directly or indirectly, will be detected. The pr ograms should adequately monitor the kinds of species of concern to the public, i.e., fish in fresh water and fish and macroinvertebrates in salt water. If the kinds of species of concern cannot be adequately monitored at a reasonable cost, appropriate surr ogate species should be monitored. The kinds of species most likely to be good surrogates are those that either (a) are a ma jor food of the desired kinds of species or (b) utilize th e same food as the desired specie s or (c) both. Even if a major adverse effect on appropriate surrogate species do es not directly result in an unacceptable effect on the kinds of species of concern to the public, it indicates a high probability that such an effect will occur.

* The term "national criteria" is used herein because it is more descriptive than the synonymous term "section 304(a) criteria", which is used in the Water Quality Standards Regulation [1].



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### To be acceptable to the public and useful in fiel d situations, protection of aquatic organisms and their uses should be defined as prevention of unacceptable long-term short-term effects on (1) commercially, recreationally, and other importa nt species and (2) (a) fish and benthic invertebrate assemblages in rivers and str eams, and (b) fish, bent hic invertebrate, and zooplankton assemblages in lakes, reservoirs , estuaries, and oceans. Monitoring programs intended to be able to detect unacceptable eff ects should be tailored to the body of water of concern so that necessary samples are obtained at enough times and places to provide adequate data on the populations of the importa nt species, as well as data directly related to the reasons for their being considered important. For example, fo r substances that are residue limited, species that are consumed should be monitored for contam inants to ensure that wildlife predators are protected, FDA action levels are not exceeded, and flavor is not impaired. Monitoring programs should also provide data on the number of taxa and number of individuals in the above-named assemblages that can be sampled at reasonable cost. The amount of decrease in the number of taxa or number of individuals in an assembla ge that should be considered unacceptable should take into account appropriate features of the body of water and its aquatic community. Because most monitoring programs can only detect decrease s of more than 20 percent, any statistically significant decrease should usually be consid ered unacceptable. The insensitivity of most monitoring programs greatly limits their usefulness for studying the validity of criteria because unacceptable changes can occur and not be detect ed. Therefore, although limited field studies can sometimes demonstrate that criteria are unde rprotective, only high quality field studies can reliably demonstrate that crit eria are not underprotective. If the purpose of water quality criteria were to protect only commercially and recreationally important species, criteria specifi cally derived to protect such sp ecies and their uses from the direct adverse effects of a material would probabl y, in most situations, also protect those species from indirect adverse effects due to effects of the material on ot her species in the ecosystem. For example, in most situations either the food ch ain would be more resist ant than the important species and their uses or the important specie s and their food chains would be adaptable enough to overcome effects of the material on portions of the food chains. These National Guidelines have been developed on the theory that effects which occur on a species in appropriate laboratory tests will gene rally occur on the same species in comparable field situations. All North Ameri can bodies of water and resident aquatic species and their uses are meant to be taken into account, except for a fe w that may be too atypical, such as the Great Salt Lake, brine shrimp, and the siscowet subspecies of lake trout, which occurs in Lake Superior and contains up to 67% fat in the fillets 4 

### . Derivation of criteria specifically for the Great Salt Lake or Lake Superior might have to take brin e shrimp and siscowet, re spectively, into account. Numerical aquatic life criteria de rived using these National Guid elines are expressed as two numbers, rather than the traditional one number, so that the criteria more accurately reflect toxicological and practical realit ies. If properly derived and use d, the combination of a maximum concentration and a continuous c oncentration should provide an a ppropriate degree of protection of aquatic organisms and their uses from acute and ch ronic toxicity to animal s, toxicity to plants, and bioaccumulation by aquatic organisms, without being as restrictive as a one-number criterion would have to be in order to pr ovide the same degree of protection. Criteria produced by these Guidelines are intende d to be useful for developing water quality standards, mixing zone standards, effluent limitations, etc. The development of such standards

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### and limitations, however, might have to take into account such addi tional factors as social, legal, economic, and hydrological consider ations, the environmental and analytical chemistry of the material, the extrapolation from laboratory data to field situations, and relationships between species for which data are available and speci es in the body of water of concern. As an intermediate step in the development of standard s, it might be desirable to derive site-specific criteria by modification of nationa l criteria to reflect such lo cal conditions as water quality, temperature, or ecologically important species 1 , 2

. 3 

### . In addition, with appropriate modifications these National Guidelines can be used to deri ve criteria for any specific geographical area, body of water (such as the Great Salt Lake), or gr oup of similar bodies of water, if adequate information is available concerning the effects of the material of concern on appropriate species and their uses. Criteria should attempt to provi de a reasonable and adequate am ount of protection with only a small possibility of considerable overprotec tion or underprotection. It is not enough that a national criterion be the best es timate that can be obtained usi ng available data; it is equally important that a criterion be de rived only if adequate appropriate data are available to provide reasonable confidence that it is a good estimate. Therefore, these National Guidelines specify certain data that should be avai lable if a numerical criterion is to be derived. If all the required data are not available, usua lly a criterion should not be derived. On the other hand, the availability of all required data does not ensure that a criterion can be derived. A common belief is that national criteria are ba sed on "worst case" assumptions and that local considerations will raise, but not lower, criteria. For example, it will usually be assumed that if the concentration of a material in a body of water is lower than the national criterion, no unacceptable effects will occur and no site-specific criterion needs to be derived. If, however, the concentration of a material in a body of water is higher than the national criterion, it will usually be assumed that a site-specific criterion should be derived. In or der to prevent the assumption of the "worst case" nature of nati onal criteria from resulting in the underprotection of too many bodies of water, national criteria must be intended to protect all or almost all bodies of water. Thus, if bodies of water and the aquatic commun ities in them do differ substantially in their sensitivities to a material, nati onal criteria should be at leas t somewhat overprotective for a majority of the bodies of water. To do otherw ise would either (a) requi re derivation of sitespecific criteria even if the site-specific con centration were substant ially below the national criterion or (b) cause the "worst case" assumption to result in the underprotection of numerous bodies of water. On the other hand, national crit eria are probably underprotective of some bodies of water. The two factors that will probably cause the most difference between national and site-specific criteria are the species that will be exposed and th e characteristics of the water. In order to ensure that national criteria are appropr iately protective, the required data for national criteria include some species that are sensitive to many material s and national criteria are specifically based on tests conducted in water relativel y low in particulate matter and organic matter. Thus, the two factors that will usually be considered in the derivation of site-specific criteria from national criteria are used to help ensure that na tional criteria are appropriately protective. On the other hand, some local conditions might requi re that site-specific criteria be lower than national criteria. Some untested locally important species might be very sensitive to the material of concern, and local water quali ty might not reduce the toxicity of the material. In addition,

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### aquatic organisms in field situations might be stressed by diseases, parasites, predators, other pollutants, contaminated or insufficient food, a nd fluctuating and extreme conditions of flow, water quality, and temperature. Further, some mate rials might degrade to more toxic materials, or some important community functions or specie s interactions might be adversely affected by concentrations lower than those th at affect individual species. Criteria must be used in a manner that is consistent with the way in which they were derived if the intended level of protection is to be provided in the real wo rld. Although derivation of water quality criteria for aquatic life is constrained by the ways toxicity and bioconcentration tests are usually conducted, there ar e still many different ways that cr iteria can be derived, expressed, and used. The means used to derive a nd state criteria should relate, in the best possible way, the kinds of data that are available con cerning toxicity and bioconcentrati on and the ways criteria can be used to protect aquatic organisms and their uses. The major problem is to determine the best way that the statement of a criterion can bridge the gap between the nearly constant concentrations used in most t oxicity and bioconcentration tests and the fluctuating concentrations that usually exist in the real world. A statement of a criterion as a number that is not to be exceeded any time or place is not acceptable because few, if any, people who use criteria would take it literally and few, if any, t oxicologists would defend a literal interpretation. Rather than try to reinterpret a crit erion that is neither usef ul nor valid, it is better to develop a more appropriat e way of stating criteria. Although some materials might not exhibit thre sholds, many materials probably do. For any threshold material, continuous exposure to a ny combination of concentrations below the threshold will not cause an unacceptable effect (as defined on pages 1 and 2) on aquatic organisms and their uses, except that the concentr ation of a required trac e nutrient might be too low. However, it is important to note that th is is a threshold of unacceptable effect, not a threshold of adverse effect. Some adverse effect , possibly even a small re duction in the survival, growth, or reproduction of a co mmercially or recreationally important species, will probably occur at, and possibly even below, the threshold. The Criterion Continuo us Concentration (CCC) is intended to be a good estimate of this thre shold of unacceptable e ffect. If maintained continuously, any concentration above the CCC is e xpected to cause an unacceptable effect. On the other hand, the concentration of a pollutant in a body of wate r can be above the CCC without causing an unacceptable effect if (a) the magnitude s and durations of the excursions above the CCC are appropriately limited and (b) there are compensating periods of time during which the concentration is below the CCC. The higher the c oncentration is above th e CCC, the shorter the period of time it can be tolerated. But it is unimportant whether there is any upper limit on concentrations that can be tolerated instantaneously or even for one minute because concentrations outside mixing zone s rarely change substantially in such short periods of time. An elegant, general approach to the problem of defining cond itions (a) and (b) would be to integrate the concentration over time, taking into account uptake and depu ration rates, transport within the organism to a critical site, etc. Because such an appro ach is not currently feasible, an approximate approach is to require that th e average concentration not exceed the CCC. The average concentration should proba bly be calculated as the arith metic average rather than the geometric mean 5 

### . If a suitable averaging period is se lected, the magnitudes and durations of concentrations above the CCC will be appropriate ly limited, and suitable compensating periods below the CCC will be required.

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### In the elegant approach mentioned above, the up take and depuration rates would determine the effective averaging period, but th ese rates are likely to vary fr om species to species for any particular material. Thus the elegant approach might not provide a defi nitive answer to the problem of selecting an appropriate averaging pe riod. An alternative is to consider that the purpose of the averaging period is to allow the concentration to be above the CCC only if the allowed fluctuating concentrations do not cause more adverse effect than would be caused by a continuous exposure to the CCC. For example, if the CCC caused a 10% reduction in growth of rainbow trout, or a 13% reduction in survival of oysters, or a 7% reduc tion in reproduction of smallmouth bass, it is the purpose of the averag ing period to allow concentrations above the CCC only if the total exposure will not cause any more adverse e ffect than continuous exposure to the CCC would cause. Even though only a few tests have compared the effects of a constant concentration with the effects of the same average con centration resulting from a fluctu ating concentration, nearly all the available comparisons have shown that substa ntial fluctuations result in increased adverse effects 5 , 6 

### . Thus if the averaging period is not to a llow increased adverse effects, it must not allow substantial fluctuations. Life-cycle tests with species such as mysids and daphnids and early life-stage tests with warmwater fishes usua lly last for 20 to 30 days. An averaging period that is equal to the length of the test will obviously allow the worst possible fluctuations and would very likely allow increased adverse effects. An averaging period of four days seems appropria te for use with the CCC for two reasons. First, it is substantially shorter than the 20 to 30 days that is obviously unacceptable. Second, for some species it appears that the results of chronic tests are due to the existence of a sensitive life stage at some time during the test 7 

### , rather than being caused by eith er long-term stress or long-term accumulation of the test material in the organi sm. The existence of a sensitive life stage is probably the cause of acute-chroni c ratios that are not much great er than 1, and is also possible when the ratio is substantially greater than 1. In addition, some experimentally determined acutechronic ratios are somewhat less than 1, possibl y because prior exposure during the chronic test increased the resistance of the sensitive life stage 8 

### . A four-day averaging period will probably prevent increased adverse eff ects on sensitive life stages by limiting the durations and magnitudes of exceedences * 

### of the CCC. The considerations applied to interpretation of the CCC also apply to the CMC. For the CMC the averaging period should again be su bstantially less than the lengths of the tests it is based on, i.e., substantially less than 48 to 96 hours. One hour is probably an a ppropriate averaging period because high concentrations of some material s can cause death in one to thr ee hours. Even when organisms do not die within the first hour or so, it is not known how many might have died due to delayed effects of this short of an exposure. Thus it is not appropriate to allow concentrations above the CMC to exist for as long as one hour. The durations of the averaging periods in nati onal criteria have been made short enough to restrict allowable fluctuations in the concentration of the pollutant in the receiving water and to restrict the length of time that the concentration in the receiving water can be continuously above

* Although "exceedence" has not been found in any dictionary, it is used here because it is not appropriate to use "violation" in conjunction with criteria, no other word s eems appropriate, and all appr opriate phrases are awkward.



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### a criterion concentrations. The statement of a cr iterion could specify that the four-day average should never exceed the CCC and that the one- hour average should ne ver exceed the CMC. However, one of the most important uses of crit eria is for designing waste treatment facilities. Such facilities are designed based on probabili ties and it is not possible to design for a zero probability. Thus, one of the impor tant design parameters is the probability that the four-day average or the one-hour-average will be exceede d, or, in other words, the frequency with which exceedences will be allowed. The frequency of allowed exceedences should be ba sed on the ability of aquatic ecosystems to recover from the exceedences, which will depend in part on the magnitudes and durations of the exceedences. It is important to realize that hi gh concentrations caused by spills and similar major events are not what is meant by an "exceedence", because spills and other accidents are not part of the design of the normal operation of wast e treatment facilities. Rather, exceedences are extreme values in the distribution of ambient concen trations and this distri bution is the result of the usual variations in the fl ows of both the effluent and the receiving water and the usual variations in the concen trations of the material of concer n in both the effluent and in the upstream receiving water. Because exceedences are the result of usual variation, most of the exceedences will be small and exceedences as large as a factor of two will be rare. In addition, because these exceedences are due to random varia tion, they will not be evenly spaced. In fact, because many receiving waters have both one-y ear and multi-year cycles and many treatment facilities have daily, weekly, and yearly cycles , exceedences will often be grouped, rather than being evenly spaced or randomly distributed. If th e flow of the receiving water is usually much greater than the flow of the effluent, normal va riation and the flow cycles will result in the ambient concentration usually being below th e CCC, occasionally being near the CCC, and rarely being above the CCC. In addition, exceed ences that do occur will be grouped. On the other hand, if the flow of the effl uent is much greater than the flow of the receiving water, the concentration might be close to the CCC much of the time and rarely above the CCC, with exceedences being randomly distributed. The abilities of ecosystems to recover differ gr eatly, and depend on the po llutant, the magnitude and duration of the exceedence, and the physical and biological featur es of the ecosystem. Documented studies of recoveries are few, but some systems recover from small stresses in six weeks whereas other systems take more than ten years to recover from severe stress 3 

### . Although most exceedences are expected to be very sma ll, larger exceedences will occur occasionally. Most aquatic ecosystems can probably recover from most exceedences in about three years. Therefore, it does not seem reasonable to pur posely design for stress above that caused by the CCC to occur more than once every three years on the average, just as it does not seem reasonable to require that these kinds of stresse s only occur once every five or ten years on the average. If the body of water is not subject to anthropoge nic stress other than the exceedences of concern and if exceedences as large as a factor of two are ra re, it seems reasonable that most bodies of water could tolerate exceedences once every three years on the aver age. In situations in which exceedences are grouped, several exceedences might occur in one or two years, but then there will be, for example, 10 to 20 years during which no exceedences will occur and the concentration will be substantially below the CCC mo st of the time. In situations in which the concentration is often close to the CCC and ex ceedences are randomly distributed, some adverse effect will occur regularly, and small additiona l, unacceptable effects will occur about every

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### third year. The relative long-te rm ecological consequences of evenly spaced and grouped exceedences are unknown, but because most exceedences will probably be small, the long-term consequences should be about e qual over long periods of time. The above considerations lead to a statement of a criterion in the fre quency-intensity-duration format that is often used to describe rain and snow fall and stream flow, e.g., how often, on the average, does more than ten inches of rain fall in a week? The numerical values chosen for frequency (or average recurrence interval), in tensity (i.e., concentration), and duration (of averaging period) are those appropr iate for national criteria. Whenever adequately justified, a national criterion may be replaced by a site-specific criterion 1 

### , which may include not only sitespecific criterion concentrations 2 

### , but also site-specific durations of averaging periods and sitespecific frequencies of allowed exceedences 3



### . The concentrations, durations, and frequencies sp ecified in criteria ar e based on biological, ecological, and toxicological data, and are designed to protect aquatic organisms and their uses from unacceptable effects. Use of criteria for designing waste treatment facilities requires selections of an appropriate wasteload allocation m odel. Dynamic models are preferred for the application of water quality criteria, but a steady-st ate model might have to be used instead of a dynamic model in some situations. Regardless of the model that is use d, the durations of the averaging periods and the frequencies of allowe d exceedences must be applied correctly if the intended level of protection is to be provided. Fo r example, in the criterion statement frequency refers to the average frequency, over a long period of time, of rare events (i.e., exceedences). However, in some disciplines, frequency is ofte n thought of in terms of the average frequency, over a long period of time, of the years is which ra re events occur, without any consideration of how many rare events occur within each of thos e eventful years. The distinction between the frequency of events and the frequency of years in important for all those situations in which the rare events, e.g., exceedences, tend to occur in groups within the eventful y ears. The two ways of calculating frequency produce the same results in s ituations in which each ra re event occurs in a different year because then the frequency of even ts is the same as the frequency of eventful years. Because fresh water and salt water have basically different chemical compositions and because freshwater and saltwater (i.e., es tuarine and true marine) species rarely inhabit the same water simultaneously, these National Guidelines provide fo r the derivation of separa te criteria for these two kinds of water. For some materials sufficient data might not be available to allow derivation of criteria for one or both kinds of water. Even though absolute toxicities might be different in fresh and salt waters, such relative data as acut e-chronic ratios and bioc oncentration factors often appear to be similar in the two waters. When data are available to indicate that these ratios and factors are probably similar, th ey are used interchangeably. The material for which a criterion is desired is us ually defined in terms of a particular chemical compound or ion, or a group of closely related compounds or ions, but it might possibly be defined in terms of an effluent. These National Guidelines might also be useful for deriving criteria for temperature, dissolved oxygen, suspe nded solids, pH, etc., if the kinds of data on which the Guidelines are based are available. Because they are meant to be applied only after a decision has been made that a national water quality criterion for aquatic organisms is needed for a material, these National Guidelines do not

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### address the rationale for making that decision. If the potential for adverse effects on aquatic organisms and their uses is part of the basis for deciding whether an aquatic life criterion is needed for a material, these Guidelines will probably be helpful in the collection and interpretation of relevant data. Su ch properties as volatility might a ffect the fate of a material in the aquatic environment and might be important wh en determining whether a criterion is needed for a material; for example, aquatic life criteria mi ght not be needed for ma terials that are highly volatile or highly degradable in water. Although such properties can affect how much of the material will get from the point of discharge through a ny allowed mixing zone to some portion of the ambient water and can also affect the size of th e zone of influence in the ambient water, such properties do not affect how much of the material aquatic organisms can tolerate in the zone of influence. This version of the National Guid elines provides clarif ications, additional de tails, and technical and editorial changes from the previous version 9 

### . These modifications are the result of comments on the previous vers ion and subsequent drafts 10 

### , experience gained during the U.S. EPA’s use of previous versions and drafts, and advances in aqua tic toxicology and related fields. Future versions will incorporate new concepts and data as their usefulness is demonstrated. The major technical changes incorporated into th is version of the Nati onal Guidelines are: 1. The requirement for acute data for freshwater animals has been changed to include more tests with invertebrate species. The taxonomic, functional, and probably the toxicological, diversities among invertebrate species are gr eater than those among vertebrate species and this should be reflected in the required data. 2. When available, 96-hr EC50s based on the percentage of fish immobilized plus the percentage of fish killed are used instead of 96-hr LC50s for fish; comparable EC50s are used instead of LC50s for othe r species. Such appropriately defined EC50s better reflect the total severe acute adverse impact of the test material on the test species than do LC50s or narrowly defined EC50s. Acute EC50s that are based on effects that are not severe, such as reduction in shell depositi on and reduction in grow th, are not used in calculating the Final Acute Value. 3. The Final Acute Value is now defined in term s of Genus Mean Acute Values rather than Species Mean Acute Values. A Genus Mean Acut e Value is the geometric mean of all the Species Mean Acute Values available for species in the genus. On the average, species within a genus are toxicologically much more similar than species in different genera, and so the use of Genus Mean Acute Values wi ll prevent data sets from being biased by an overabundance of species in one or a few genera. 4. The Final Acute Value is now calculated using a method 11 

### that is not subject to the bias and anomalous behavior that the previous method was. The new method is also less influenced by one very low value because it al ways gives equal weight to the four values that provide the most information about th e cumulative probability of 0.05. Although the four values receive the most weight, the other values do have a substantial effect on the Final Acute Value (see examples in Appendix 2).
5. The requirements for using the results of tests with aquatic plants have been made more stringent.

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### 6. Instead of being equal to the Final Acute Va lue, the Criterion Maximum Concentration is now equal to one-half the Final Acute Valu e. The Criterion Maximum Concentration is intended to protect 95 percen t of a group of diverse genera, unless a commercially or recreationally important species is very sens itive. However, a concentration that would severely harm 50 percent of the fifth percen tile or 50 percent of a sensitive important species cannot be considered to be protective of that percentile or that species. Dividing the Final Acute Value by 2 is intended to resu lt in a concentration that will not severely adversely affect too many of the organisms.
7. The lower of the two numbers in the crit erion is now called th e Criterion Continuous Concentration, rather than the Criterion Average Concentration, to more accurately reflect the nature of the toxico logical data on which it is based. 8. The statement of a criterion has been cha nged (a) to include durations of averaging periods and frequencies of allowed exceedence s that are based on what aquatic organisms and their uses can tolerate, a nd (b) to identify a specific s ituation in which site-specific criteria 1 , 2 , 3 

### are probably desirable. In addition, Appendix 1 was added to aid in dete rmining whether a species should be considered resident in North America and its taxonomic classification. Appe ndix 2 explains the calculation of the Final Acute Value. The amount of guidance in these National Guide lines has been increased, but much of the guidance is necessarily qualitative rather than quantitative; much judgment will usually be required to derive a water qual ity criterion for aquatic organi sms and their uses. In addition, although this version of the Nationa l Guidelines attempts to cover all major questions that have arisen during use of previous versions and draf ts, it undoubtedly does not cover all situations that might occur in the future. All necessary deci sions should be based on a thorough knowledge of aquatic toxicology and an understanding of these Guidelines and should be consistent with the spirit of these Guidelines, i.e., to make best use of the available data to derive the most appropriate criteria. These Nati onal Guidelines should be modifi ed whenever sound scientific evidence indicates that a nationa l criterion produced using these Guidelines would probably be substantially overprotective or underprotective of the aquatic organisms and their uses on a national basis. Derivation of nu merical national water quality crit eria for aquatic organisms and their uses is a complex process and requires knowl edge in many areas of aquatic toxicology; any deviation from these Guidelines should be carefully considered to ensure that it is consistent with other parts of these Guidelines.

I. Definition of Material of Concern A. Each separate chemical that does not ionize substantially in most natural bodies of water should usually be considered a separate material, except possibly for structurally similar organic compounds th at only exist in large quantities as commercial mixtures of various compounds and apparently have similar biological, chemical, physical, and toxicological properties.
B. For chemicals that do ionize s ubstantially in most natura l bodies of water (e.g., some phenols and organic acids, some salts of phenols and organic acids, and most

9

### inorganic salts and coordinati on complexes of metals), all forms that would be in chemical equilibrium should usually be c onsidered one material. Each different oxidation state of a metal and each di fferent nonionizable covalently bonded organometallic compound should usually be considered a separate material. C. The definition of the material should in clude an operational an alytical component. Identification of a material simply, for ex ample, as "sodium" obviously implies "total sodium", but leaves room for doubt. If "total " is meant, it should be explicitly stated. Even "total" has different operational definitions, some of which do not necessarily measure "all that is there" in all samples. Thus, it is also necessary to reference or describe the analytical method that is in tended. The operational analytical component should take into account the analytical and environmental chemistry of the material, the desirability of using the same analyti cal method on samples from laboratory tests, ambient water, and aqueous effluents, and various practical considerations, such as labor and equipment requirements a nd whether the method would require measurement in the field or would allow measurement after samples are transported to a laboratory. The primary requirements of the operational analytical component are that it be appropriate for use on samples of receiving water, that it be compatible with the available toxicity and bioaccumulation data without making extrapolations that are too hypothetical, and that it rarely result in underprotection or overprotection of aquatic organisms and their uses. Because an ideal analytical measurement will rarely be available, a compromise measurement will usually have to be used. This compromise measurement must fit with th e general approach that if an ambient concentration is lower than the national criterion, unacceptable effects will probably not occur, i.e., the compromise meas urement must not err on the side of underprotection when measurements are made on a surface water. Because the chemical and physical properties of an efflue nt are usually quite different from those of the receiving water, an analytical method that is acceptable for analyzing an effluent might not be appropriate for analyz ing a receiving water, and vice versa. If the ambient concentration calculated from a measured concentration in an effluent is higher than the national criteri on, an additional option is to measure the concentration after dilution of the effluent with receiving water to determine if the measured concentration is lowered by such phenomena as complexation or sorption. A further option, of course, is to deri ve a site-specific criterion 1 , 2 , 3 

### . Thus, the criterion should be based on an appropriate analytical meas urement, but the crit erion is not rendered useless if an ideal measurement either is not available or is not feasible. NOTE: The analytical chemistry of the materi al might have to be taken into account when defining the material or when judging th e acceptability of so me toxicity tests, but a criterion should not be based on the sensitivity of an analytical method. When aquatic organisms are more sensitive than routine analytical methods, the proper solution is to develop better analytical methods, not to underprotect aquatic life.

10

### II. Collection of Data A. Collect all available data on the mate rial concerning (a) toxicity to, and bioaccumulation by, aquatic animals and plants, (b) FDA action levels 12 

### , and (c) chronic feeding studies and long-term field st udies with wildlife sp ecies that regularly consume aquatic organisms.
B. All data that are used should be availa ble in typed, dated, and signed hard copy (publication, manuscript, letter, memorandum, etc.) with enough supporting information to indicate that acceptable test procedures were used and that the results are probably reliable. In some cases it may be appropriate to obt ain additional written information from the investigator, if possi ble. Information that is confidential or privileged or otherwise not available for distribution should not be used. C. Questionable data, whether published or unpublished, should not be used. For example, data should usually be rejected if they are from tests th at did not contain a control treatment, tests in which too many or ganisms in the control treatment died or showed signs of stress or disease, and test s in which distilled or deionized water was used as the dilution water withou t addition of appropriate salts.
D. Data on technical grade materials may be us ed if appropriate, but data on formulated mixtures and emulsifiable concentrates of the material of concern should not be used.
E. For some highly volatile, hydrolyzable, or degradable materials it is probably appropriate to use only results of flow-through tests in wh ich the concentrations of test material in the test solutions we re measured often enough using acceptable analytical methods.
F. Data should be rejected if they were obtained using: 1. Brine shrimp, because they usually only o ccur naturally in water with salinity greater than 35 g/kg. 2. Species that do not have reproducing wild populations in North America (see Appendix 1). 3. Organisms that were previously exposed to substantial concentrations of the test material or other contaminants. G. Questionable data, data on formulated mixt ures and emulsifiable concentrates, and data obtained with non-resident species in North America or previously exposed organisms may be used to provide auxiliary information but should not be used in the derivation of criteria.

III. Required data A. Certain data should be available to help en sure that each of the four major kinds of possible adverse effects receives adequate c onsideration. Results of acute and chronic toxicity tests with representative species of aquatic animals are necessary so that data available for tested species can be considered a useful indication of the sensitivities of

11

### appropriate untested species. Fewer data concerning toxic ity to aquatic plants are required because procedures for conducting tests with plants and interpreting the results of such tests are not as well de veloped. Data concerning bioaccumulation by aquatic organisms are only re quired if relevant data are available concerning the significance of residues in aquatic organisms.
B. To derive a criterion for freshwater aqua tic organisms and their uses, the following should be available: 1. Results of acceptable acute tests (see Section IV) with at least one species of freshwater animal in at least eight different families such that all of the following are included:

a. the family Salmonidae in the class Osteichthyes b. a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish, etc.)

c. a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.) d. a planktonic crustacean (e.g., cladoceran, copepod, etc.)

e. a benthic crustacean (e.g., os tracod, isopod, amphipod, crayfish, etc.) f. an insect (e.g., mayfly, dragonf ly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)
g. a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.) h. a family in any order of ins ect or any phylum not already represented. 2. Acute-chronic ratios (see Section VI) w ith species of aquatic animals in at least three different families provided that one of the three species:

• at least one is a fish

• at least one is an invertebrate

• at least one is an acutely sensitiv e freshwater species (the other two may be saltwater species). 3. Results of at least one acceptable test with a freshwater alga or vascular plant (see Section VIII). If plants are among the aquatic organisms that are most sensitive to the material, results of a test with a plant in another phylum (division) should also be available.

12

### 4. At least one acceptable bioconcentrat ion factor determined with an appropriate freshwater species, if a maximum permissible tissue concentration is available (see Section IX). C. To derive a criterion for saltwater aqua tic organisms and their uses, the following should be available: 1. Results of acceptable acute tests (see S ection IV) with at l east one species of saltwater animal in at least eight different families such that all of the following are included:

a. two families in the phylum Chordata b. a family in a phylum other than Arthropoda or Chordata

c. either the Mysidae or Penaeidae family d. three other families not in the phylum Chordata (may include Mysidae or Penaeidae, whic hever was not used above)

e. any other family. 2. Acute-chronic ratios (see Section VI) w ith species of aquatic animals in at least three different families provided that of the three species:

• at least one is a fish

• at least one is an invertebrate

• at least one is an acutely sensitive sa ltwater species (the other two may be freshwater species). 3. Results of at least one acceptable test w ith a saltwater alga or vascular plant (see Section VIII). If plants are amon g the aquatic organisms most sensitive to the material, results of a test with a plant in another phylum (division) should also be available. 4. At least one acceptable bioconcentrat ion factor determined with an appropriate saltwater species, if a ma ximum permissible tissue concentration is available (see Section IX).
D. If all the required data ar e available, a numerical crit erion can usually be derived, except in special cases. For example, deriva tion of a criterion might not be possible if the available acute-chronic ratios vary by more than a factor of ten with no apparent pattern. Also, if a criterion is to be related to a water quality characteristic (see Sections V and VII), more data will be necessary. Similarly, if all required data are not avai lable, a numerical cr iterion should not be derived except in special cases. For exam ple, even if not enough acute and chronic data are available, it might be possible to derive a criterion if the available data

13

### clearly indicate that the Final Residue Value should be much lower than either the Final Chronic Value or Final Plant Value.
E. Confidence in a criterion usua lly increases as the amount of available pertinent data increases. Thus, additional data are usually desirable.

IV. Final Acute Value A. Appropriate measures of the acute (short-term) toxicity of the mate rial to a variety of species of aquatic animals ar e used to calculate the Fina l Acute Value. The Final Acute Value is an estimate of the concentration of the material corresponding to a cumulative probability of 0.05 in the acute toxi city values for the genera with which acceptable acute tests have been conducted on the material. However, in some cases, if the Species Mean Acute Value of a commercially or recreationally important species is lower than the calculated Final Ac ute Value, then that Species Mean Acute Value replaces the calculated Final Acute Va lue in order to provide protection for that important species.
B. Acute toxicity tests should have been conducted using acceptable procedures 13



### . C. Except for test with saltwater annelids and mysids, results of acute tests during which the test organisms were fed should not be used, unless data indicate that the food did not affect the toxicity of the test material.
D. Results of acute tests conducted in unusua l dilution water, e.g., dilution water in which total organic carbon or particulate matter exceeded 5 mg/L, should not be used, unless a relationship is developed between acute toxicity and organic carbon or particulate matter or unless da ta show that organic carbon, particulate matter, etc., do not affect toxicity.
E. Acute values should be based on endpoints which reflect the total severe acute adverse impact of the test material on the organisms used in the test. Therefore, only the following kinds of data on acute toxi city to aquatic animals should be used: 1. Tests with daphnids and other cladocerans should be started with organisms less than 24 hours old and tests with midges s hould be started with second- or thirdinstar larvae. The result should be the 48-hr EC50 based on percentage of organisms immobilized plus percentage of organisms killed. If such an EC50 is not available from a test, the 48-hr LC50 should be used in place of the desired 48-hr EC50. An EC50 or LC50 of longer than 48 hr can be used as long as the animals were not fed and the control animals were acceptable at the end of the test. 2. The result of a test with embryos and larvae of barnacles, bivalve molluscs (clams, mussels, oysters, and scallops), s ea urchins, lobsters, crabs, shrimp, and abalones, should be the 96-hr EC50 based on the percentage of organisms with incompletely developed shells plus the percentage of organisms killed. If such an EC50 is not available from a test, th e lower of the 96-hr EC50 based on the percentage of organisms with incomplete ly developed shells and the 96-hr LC50

14

### should be used in place of the desired 96- hr EC50. If the duration of the test was between 48 and 96 hr, the EC50 or LC50 at the end of the test should be used. 3. The acute values from tests with all othe r freshwater and saltwater animal species and older life stages of barnacles, bivalv e molluscs, sea urchins, lobsters, crabs, shrimps, and abalones should be the 96- hr EC50 based on the percentage of organisms exhibiting loss of equilibrium plus the percentage of organisms immobilized plus the percentage of orga nisms killed. If such an EC50 is not available from a test, the 96-hr LC50 should be used in place of the desired 96-hr EC50. 4. Tests with single-celled organisms are not considered acute tests, even if the duration was 96 hours or less.
5. If the tests were conducted properly, acute values re ported as "greater than" values and those which are above the sol ubility of the test material should be used, because rejection of such acute va lues would unnecessarily lower the Final Acute Value by eliminating acute values for resistant species.
F. If the acute toxicity of the material to aquatic animals apparently has been shown to be related to a water quality characteristic such as hardness or particulate matter for freshwater animals or salinity or partic ulate matter for saltwater animals, a Final Acute Equation should be derived based on th at water quality characteristic. Go to Section V. G. If the available data indicate that one or more life stages are at least a factor of two more resistant than one or more other life st ages of the same species, the data for the more resistant life stages should not be used in the calculation of the Species Mean Acute Value because a species can only be c onsidered protected from acute toxicity if all life stages are protected.
H. The agreement of the data within and betw een species should be considered. Acute values that appear to be questionable in comparison with other acute and chronic data for the same species and for other species in the same genus probably should not be used in calculation of a Species Mean Acute Value. For example, if the acute values available for a species or genus differ by more than a factor of 10, some or all of the values probably should not be used in calculations.
I. For each species for which at least one acute value is available, the Species Mean Acute Value (SMAV) should be calculated as the geometric mean of the results of all flow-through tests in which the concentrations of test material were measured. For a species for which no such result is availabl e, the SMAV should be calculated as the geometric mean of all availa ble acute values, i.e., resu lts of flow-through tests in which the concentrations were not measured and results of sta tic and renewal tests based on initial concentrations (nominal concentrations ar e acceptable for most test materials if measured concentrations are not available) of test material. NOTE: Data reported by original investigator s should not be rounded off. Results of all intermediate calculations should be rounded 14 

### to four significant digits.

15

### NOTE: The geometric mean of N numbers is the Nth root of the product of the N numbers. Alternatively, the geometri c mean can be calculated by adding the logarithms of the N numbers, dividing th e sum by N, and taking the antilog of the quotient. The geometric mean of two numbers is the square root of the product of the two numbers, and the geometric mean of one number is that number. Either natural (base e) or common (base 10) logarithms can be used to calculate geometric means as long as they are used consistently within each set of data, i.e., the antilog used must match the logarithm used. NOTE: Geometric means, rather than arithmetic means, are used here because the distributions of sensitivities of individual organisms in toxicity tests on most materials and the distributions of sensitivities of species within a genus are more likely to be lognormal than normal. Sim ilarly, geometric means are used for acutechronic ratios and bioconcentra tion factors because quotients ar e likely to be closer to lognormal than normal distributions. In addi tion, division of the geometric mean of a set of numerators by the geometric mean of the set of corresponding denominators will result in the geometric mean of the set of corresponding quotients.
J. For each genus for which one or more SMAVs are available, the Genus Mean Acute Value (GMAV) should be calculated as the geometric mean of the SMAVs available for the genus.
K. Order the GMAVs from high to low.
L. Assign ranks, R, to the GMAVs from "1" for the lowest to "N" for the highest. If two or more GMAVs are identical, arbitr arily assign them successive ranks.
M. Calculate the cumulative probability, P, for each GMAV as R/(N+1).
N. Select the four GMAVs which have cumula tive probabilities closest to 0.05 (if there are less than 59 GMAVs, these will alwa ys be the four lowest GMAVs). O. Using the selected GMAVs and Ps, calculate

S 2 

### = )4/))((()( 4/))ln(())((ln

2 2 2 

# ∑∑ ∑ ∑

− − P F GMAV

GMAV



### L = 

# ∑ ∑

− 4/)))(()(ln( PSGMAV

A = 

### L S +

)05.0(
FAV = A 

### e 

### (See 11 

### for development of the calculation pr ocedure and Appendix 2 for an example calculations and computer program.) NOTE: 

### Natural logarithms (logarithms to ba se e, denoted as ln) are used herein merely because they are easier to use on some hand calculators and computers than common (base 10) logarithms. Consistent us e of either will produce the same result.

16

### P. If for a commercially or recreationally im portant species the geometric mean of the acute values from the flow-through tests in which the con centrations of test material were measured is lower than the calculated Final Acute Value, then that geometric mean should be used as the Final Acute Va lue instead of the cal culated Final Acute Value. Q. Go to Section VI.

V. Final Acute Equation 

### A. When enough data are available to show that acute toxicity to two or more species is similarly related to a water quality characte ristic, the relationship should be taken into account as described in S ections B-G below or using analysis of covariance 15 , 16



### . The two methods are equivalent and produce identical results. The manual meth described below provides an understanding of this application of covariance analysis, but computerized versions of covariance analysis are much more convenient for analyzing large data sets. If two or more factors affect toxicity, multiple regression analysis should be used. od

B. For each species for which comparable acute toxicity values are available at two or more different values of the water qual ity characteristic, perform a least squares regression of the acute toxi city values on the corres ponding values of the water quality characteristic to obtain the slope and its 95% confidence limits for each species. NOTE: 

### Because the best documented relations hip is that between hardness and acute toxicity of metals in fresh water and a l og-log relationship fits these data, geometric means and natural logarithms of both toxicity and water qualit y are used in the rest of this section. For relationships based on ot her water quality characteristics, such as pH, temperature, or salinity, no transforma tion or a different transformation might fit the data better, and appropriate changes will be necessary throughout this section. C. Decide whether the data for each species is useful, taking into account the range and number of the tested values of the wate r quality characteristic and the degree of agreement within and between species. For example, a slope based on six data points might be of limited value if it is based only on data for a very narrow range of values of the water quality characteristic. A sl ope based on only two da ta points, however, might be useful if it is consistent with ot her information and if the two points cover a broad enough range of the water quality charac teristic. In addition, acute values that appear to be questionable in comparison w ith other acute and chronic data available for the same species and for other species in the same genus probably should not be used. For example, if after adjustment for the water quality characteristic, the acute values available for a species or genus differ by more than a factor of 10, rejection of some or all of the values is probably appropria te. If useful slopes are not available for at least one fish and one inve rtebrate or if the available slopes are too dissimilar or if too few data are available to adequately define the relationship between acute toxicity and the water quality characteristic, return to Section IV.G., using the results of tests

17

### conducted under conditions and in waters sim ilar to those commonly used for toxicity tests with the species.
D. Individually for each species calculate th e geometric mean of the available acute values and then divide each of the acute values for a species by the mean for the species. This normalizes the acute values so that the geometric mean of the normalized values for each species individually and for any combin ation of species is 1.0.
E. Similarly normalize the values of the wate r quality characteristic for each species individually.
F. Individually for each species perform a l east squares regression of the normalized acute toxicity values on the corresponding normalized values of the water quality characteristic. The resulting slopes and 95% confidence limits will be identical to those obtained in Section B above. Now, howev er, if the data are actually plotted, the line of best fit for each individual species will go through the point 1,1 in the center of the graph. G. Treat all the normalized data as if they we re all for the same species and perform a least squares regression of all the normalized acute values on the corresponding normalized values of the water quality charac teristic to obtain th e pooled acute slope, V, and its 95% confidence limits. If all the normalized data are actually plotted, the line of best fit will go through the poi nt 1,1 in the center of the graph.
H. For each species calculate the geometric mean, W, of the acute toxi city values and the geometric mean, X, of the values of the water quality characteristic. (These were calculated in steps D and E above.)
I. For each species calculate the logarithm, Y, of the SMAV at a selected value, Z, of the water quality characteris tic using the equation: Y = ln W – V(ln X – ln Z).
J. For each species calculate the SMAV at Z using the equation: SMAV = e Y



### . NOTE: 

### Alternatively, the SMAVs at Z can be obtained by ski pping step H above, using the equations in steps I and J to adjust each acute value individually to Z, and then calculating the geometric mean of the adjusted values for each species individually. This alternative procedure al lows an examination of the range of the adjusted acute values for each species.
K. Obtain the Final Acute Value at Z by using the procedure describe d in Section IV.JO.
L. If the SMAV at Z of a commercially or recr eationally important species is lower than the calculated Final Acute Value at Z, th en that SMAV should be used as the Final Acute Value at Z instead of the calculated Final Acute Value.
M. The Final Acute Equation is written as: Final Acute Value = e (V[ln(water quality characteristic)] + ln A – V[ln Z]) 

### , where V = pooled acute slope and A = Final Acute Value at Z. Because

18

### V, A, and Z are known, the Final Acute Va lue can be calculated for any selected value of the water quality characteristic.

VI. Final Chronic Value 

### A. Depending on the data that are available concerning chronic toxicity to aquatic animals, the Final Chronic Value might be ca lculated in the same manner as the Final Acute Value or by dividing th e Final Acute Value by the Fi nal Acute-Chronic Ratio. In some cases it may not be possible to calculate a Final Chronic Value. NOTE: 

### As the name implies, the acute-ch ronic ration (ARC) is a way of relating acute and chronic toxicities. The acute-chr onic ratio is basically the inverse of the application factor, but this new name is better because it is more descriptive and should help prevent confusion between "appl ication factors" and "safety factors". Acute-chronic ratios and applic ation factors are ways of re lating the acute and chronic toxicities of a material to aquatic organisms. Safety factors are used to provide an extra margin of safety beyond the known or estimated sensitivities of aquatic organisms. Another advantage of the acute-chronic ratio is that it will usually be greater than one; this should avoid the c onfusion as to whethe r a large application factor is one that is close to unity or one that has a denominator that is much greater than the numerator.
B. Chronic values should be based on resu lts of flow-through (except renewal is acceptable for daphnids) chronic tests in which the concentrations of test material in the test solutions were properly measured at appropriate ti mes during the test. C. Results of chronic tests in which survival , growth, or reproduc tion in the control treatment was unacceptably low should not be used. The limits of acceptability will depend on the species.
D. Results of chronic tests conducted in unusua l dilution water, e.g., dilution water in which total organic carbon or particulate matter exceeded 5 mg/L, should not be used, unless a relationship is deve loped between chronic toxic ity and organic carbon or particulate matter or unless data show that organic carbon, particulate matter, etc., do not affect toxicity.
E. Chronic values should be based on endpoints and lengths of expos ure appropriate to the species. Therefore, only results of the following kinds of chronic toxicity tests should be used: 1. Life-cycle toxicity tests c onsisting of exposures of each of two or more groups of individuals of a species to a different concentration of the test material throughout a life cycle. To ensure that all life st ages and life processes are exposed, tests with fish should begin with embryos or newly hatched young less than 48 hours old, continue through maturation and re production, and should end not less than 24 days (90 days for salmonids) after the ha tching of the next generation. Tests with daphnids should begin with young less than 24 hours old and last for not less than 21 days. Tests with mysids shoul d begin with young less than 24 hours old and continue until 7 days past the medi an time of first brood release in the

19

### controls. For fish, data should be obtai ned and analyzed on survival and growth of adults and young, maturati on of males and females, eggs spawned per female, embryo viability (salmonids only), and hatchability. Fo r daphnids, data should be obtained and analyzed on survival and young per female. For mysids, data should be obtained and analyzed on survival, growth, and young per female. 2. Partial life-cycle toxicity tests consisti ng of exposures of each of two or more groups of individuals of a species of fish to a different concen tration of the test material through most portions of a life cy cle. Partial life-cy cle tests are allowed with fish species that require more than a year to reach sexual ma turity, so that all major life stages can be exposed to the te st material in less than 15 months. Exposure to the test material should begi n with immature juveniles at least 2 months prior to active g onad development, continue through maturation and reproduction, and end not less than 24 da ys (90 days for salmonids) after the hatching of the next generation. Data should be obtained and analyzed on survival and growth of adults and young, maturation of males and females, eggs spawned per female, embryo viability (salmonids only), and hatchability. 3. Early life-stage toxicity te sts consisting of 28- to 32-day (60 days post hatch for salmonids) exposures of the early life stages of a species of fish from shortly after fertilization through embryonic, larval, a nd early juvenile development. Data should be obtained and analy zed on survival and growth. NOTE: 

### Results of an early life-stage test are used as predictions of results of life-cycle and partial life-cycle tests with the same species. Therefore, when results of a life-cycle or pa rtial life-cycle test are available, results of an early lifestage test with the same species should not be used. Also, results of early lifestage tests in which the incidence of mortalities or abnormalities increased substantially near the end of the test s hould not be used because results of such tests are possibly not good pr edictions of the results of comparable life-cycle or partial life-cycle tests.
F. A chronic value may be obtai ned by calculating the geometric mean of the lower and upper chronic limits from a chronic test or by analyzing chronic da ta using regression analysis. A lower chronic limit is the highest tested concentration (a) in an acceptable chronic test, (b) which did not cause an unacceptable amount of adverse effect on any of the specified biological measurements, and (c) below which no tested concentration caused an unacceptable effect. An upper chronic limit is the lowest tested concentration (a) in an acceptabl e chronic test, (b) which did cause an unacceptable amount of adverse effect on one or more of the specified biological measurements, and (c) above which all test ed concentrations also caused such an effect. NOTE: 

### Because various authors have used a variety of terms and definitions to interpret and report results of chronic test s, reported results should be reviewed carefully. The amount of effect that is considered unacceptable is often based on a statistical hypothesis test, but might also be defined in terms of a specified percent reduction from the controls. A small pe rcent reduction (e.g., 3%) might be

20

### considered acceptable even if it is statistica lly significantly different from the control, whereas a large percent reduction (e.g., 30%) might be considered unacceptable even if it is not statistically significant. G. If the chronic toxicity of the material to aquatic animals apparently has been shown to be related to a water quality characteristic such as hardness or particulate matter for freshwater animals or salinity or partic ulate matter for saltwater animals, a Final Chronic Equation should be de rived based on that water qual ity characteristic. Go to Section VII.
H. If chronic values are available for species in eight families as described in Sections III.B.1 or III.C.1, a Species Mean Chronic Value (SMCV) should be calculated for each species for which at least one chroni c value is available by calculating the geometric mean of all chronic values availa ble for the species, and appropriate Genus Mean Chronic Values should be calculated. The Final Chronic Value should then be obtained using the procedure described in Section IV.J-O. Then go to Section VI.M.
I. For each chronic value for which at least one corresponding appropria te acute value is available, calculate an acute-chronic rati o, using for the numerator the geometric mean of the results of all acceptable flow -through (except static is acceptable for daphnids) acute tests in the same dilution wa ter and in which the concentrations were measured. For fish, the acute test(s) should have been conducted with juveniles. The acute test(s) should have been part of the sa me study as the chronic test. If acute tests were not conducted as part of the same study, acute tests con ducted in the same laboratory and dilution water, but in a different study, may be used. If no such acute tests are available, results of acute tests conducted in th e same dilution water in a different laboratory may be used. If no such acute tests are available, an acutechronic ratio should not be calculated.
J. For each species, calculate the species mean acute-chronic ratio as the geometric mean of all acute-chronic ratios available for that species.
K. For some materials the acute-chronic ratio seems to be the same for all species, but for other materials the ratio seems to increa se or decrease as the Species Mean Acute Value (SMAV) increases. Thus the Final Acute-Chronic Ratio can be obtained in four ways, depending on the data available: 1. If the species mean acute-chronic ratios seems to increase or decrease as the SMAV increases, the Final Acute-Chronic Ratio should be ca lculated as the geometric mean of the acute-chronic ratios for species whose SMAVs are close to the Final Acute Value. 2. If no major trend is apparent and the acute-chronic ratios for a number of species are within a factor of ten, the Final Acut e-Chronic Ratio should be calculated as the geometric mean of a ll the species mean acute-chronic ratios available for both freshwater and saltwater species. 3. For acute tests conducted on metals a nd possibly other substances with embryos and larvae of barnacles, biva lve molluscs, sea urchins, lobsters,

21

### crabs, shrimp, and abalones (see Section IV.E.2), it is probably appropriate to assume that the acute-chronic ratio is 2. Chronic tests are very difficult to conduct with most such species, but it is likely that the sensitivities of embryos and larvae would determine the re sults of life-cycle tests. Thus, if the lowest available SMAVs were determined with embryos and larvae of such species, the Final Acute-Chronic Ratio should probably be assumed to be 2, so that the Final Chronic Valu e is equal to the Criterion Maximum Concentration (see Section XI.B). 4. If the most appropriate species mean acu te-chronic ratios are less than 2.0, and especially if they are less than 1.0, acclimation has proba bly occurred during the chronic test. Because continuous exposure and acclimation cannot be assured to provide adequate protection in field situations , the Final AcuteChronic Ratio should be assumed to be 2, so that the Final Chronic Value is equal to the Criterion Maximum Co ncentration (see Section XI.B). If the available specie s mean acute-chronic ratios do not fit one of these cases, a Final Acute-Chronic Ratio probably cannot be obtained, and a Final Chronic Value probably cannot be calculated.
L. Calculate the Final Chronic Value by di viding the Final Acut e Value by the Final Acute-Chronic Ratio. If there was a Final Acute Equation rather than a Final Acute Value, see also Section VII.A.
M. If the Species Mean Chronic Value of a commercially or recreationally important species is lower than the calculated Final Chronic Value, then that Species Mean Chronic Value should be used as the Final Chronic Value instead of the calculated Final Chronic Value.
N. Go to Section VIII.

VII. Final Chronic Equation 

### A. A Final Chronic Equation can be derived in two ways. The procedure described here in Section A will result in the chronic slope being the same as the acute slope. The procedure described in Sections B-N will usually result in the chronic slope being different from the actual slope. 1. If acute-chronic ratios ar e available for enough speci es at enough values of the water quality characteristic to indi cate that the acute-chronic ratio is probably the same for all species and is probably i ndependent of the water quality characteristic, calculate the Final Acute-Chronic Ratio as the geometric mean of the available species mean acute-chronic ratios. 2. Calculate the Final Chronic Value at the selected value Z of the water quality characteristic by dividing the Final Acute Value at Z (see Section V.M.) by the Final Acute-Chronic Ratio.

22

### 3. Use V = pooled acute slope (see sec tion V.M.) as L = pooled chronic slope. 4. Go to Section VII.M.
B. When enough data are available to show that chronic toxicity to at least one species is related to a water quality char acteristic, the rela tionship should be taken into account as described in Sections B-G below or using an alysis of covariance 15 , 16 

### . The two methods are equivalent and produce identic al results. The manual method described below provides an understanding of this application of covariance analysis, but computerized versions of covariance analysis are much more convenient for analyzing large data sets. If two more factors affect toxicity, multiple regression analysis should be used. C. For each species for which comparable chronic toxicity values are available at two or more different values of the water qual ity characteristic, perform a least squares regression of the chronic toxicity values on the corresponding values of the water quality characteristic to obtain the slope and its 95% confidence limits for each species. NOTE: 

### Because the best documented relations hip is that between hardness and acute toxicity of metals in fresh water and a l og-log relationship fits these data, geometric means and natural logarithms of both toxicity and water qualit y are used in the rest of this section. For relationships based on ot her water quality characteristics, such as pH, temperature, or salinity, no transforma tion or a different transformation might fit the data better, and appropriate changes will be necessary throughout this section. It is probably preferable, but not necessary, to use the same transformation that was used with the acute values in Section V.
D. Decide whether the data for each species is useful, taking into account the range and number of the tested values of the wate r quality characteristic and the degree of agreement within and between species. For example, a slope based on six data points might be of limited value if it is based only on data for a very narrow range of values of the water quality characteristic. A slope based on only two da ta points, however, might be useful if it is consistent with ot her information and if the two points cover a broad enough range of the water quality characteristic. In addition, chronic values that appear to be questionable in comp arison with other acute and chronic data available for the same species and for ot her species in the same genus probably should not be used. For example, if after adjustment fo r the water quality characteristic, the chronic values available for a species or genus differ by more than a factor of 10, rejection of some or all of the values is probably appropriate. If a useful chronic slope is not available for at least one species or if the available slopes are too dissimilar or if too few data are available to adequately define the relationship between chronic toxicity and the water qual ity characteristic, it might be appropriate to assume that the chronic slope is the same as the acute slope, which is equivalent to assuming that the acute-chronic ratio is independent of the water quality characteristic. Alternativel y, return to Section VI.H, using the results of tests

23

### conducted under conditions and in waters sim ilar to those commonly used for toxicity tests with the species.
E. Individually for each species calculate the geometric mean of the available chronic values and then divide each chronic value for a species by the mean for the species. This normalizes the chronic values so th at the geometric mean of the normalized values for each species individually and for any combin ation of species is 1.0.
F. Similarly normalize the values of the wate r quality characteristic for each species individually. G. Individually for each species perform a l east squares regression of the normalized chronic toxicity values on the correspondi ng normalized values of the water quality characteristic. The resulting slopes and th e 95% confidence limits will be identical to those obtained in Section B above. Now, howev er, if the data are actually plotted, the line of best fit for each individual species will go through the point 1,1 in the center of the graph.
H. Treat all the normalized data as if they we re all for the same species and perform a least squares regression of all the norm alized chronic values on the corresponding normalized values of the water quality char acteristic to obtai n the pooled chronic slope, L, and its 95% confidence limits. If all the normalized data are actually plotted, the line of best fit will go through the point 1,1 in the center of the graph.
I. For each species calculate the geometric mean, M, of the toxicity values and the geometric mean, P, of the values of the water quality characteristic. (These were calculated in steps E and F above.)
J. For each species calculated the logarithm, Q, of the Species Mean Chronic Value at a selected value, Z, of the water quality characteristic using the equation: Q = ln M – L(ln P – ln Z).
NOTE: 

### Although it is not necessary, it will usua lly be best to use the same value of the water quality characteristic here as was used in Section V.I.
K. For each species calculate a Species Mean Chronic Value at Z using the equation: SMCV = e Q



### . NOTE: 

### Alternatively, the Species Mean Ch ronic Values at Z can be obtained by skipping step J above, using th e equations in steps J and K to adjust each acute value individually to Z and then calculating the geometric means of the adjusted values for each species individually. This alternativ e procedure allows an examination of the range of the adjusted chroni c values for each species.
L. Obtain the Final Chronic Value at Z by usi ng the procedure descri bed in Section IV.JO.
M. If the Species Mean Chronic Value at Z of a commercially or recreationally important species is lower than the calculated Final Ch ronic Value at Z, then that Species Mean

24

### N. The Final Chronic Equation is writ ten as: Final Chronic Value = e (L[ln(water quality characteristic)] + ln S – L [ln Z]) 

### , where L = pooled chronic slope and S = Final Chronic Value at Z. Because L, S and Z are known, the Final Chronic Value can be calculated for any selected value of the water quality characteristic.

VIII. Final Plant Value 

### A. Appropriate measures of the to xicity of the material to aquatic plants are used to compare the relative sensitivitie s of aquatic plants and animals. Although procedures for conducting and interpreting the results of toxicity tests with plants are not well developed, results of tests w ith plants usually indicate that criteria which adequately protect aquatic animals and their uses will probably also protect aquatic plants and their uses.
B. A plant value is the result of a 96-hr test conducted with an alga or a chronic test conducted with an aquatic vascular plant. NOTE: 

### A test of the toxicity of a metal to a plant usually should not be used if the medium contained an excessive amount of a complexing agent, such as EDTA, that might affect the toxicity of the metal. Concentrations of EDTA above about 200 μ g/L should probably be c onsidered excessive. C. The Final Plant Value should be obtained by selecting the lowest result from a test with an important aquatic plant species in which the concentrations of test material were measured and the endpoint was biologically important.

IX. Final Residue Value 

### A. The Final Residue Value is intended to (a) prevent concentrations in commercially or recreationally important aquatic species fr om affecting marketability because of exceedance of applicable FDA action levels and (b) protect wildlif e, including fishes and birds, that consume aquatic organisms from demonstrated unacceptable effects. The Final Residue Value is the lowest of the residue values that are obtained by dividing maximum permissible tissue concen trations by appropriate bioconcentration or bioaccumulation factors. A maximum permissible tissue concentration is either (a) an FDA action level 12 

### for fish oil or for the edible porti on of fish or shellfish, or (b) a maximum acceptable dietary intake based on observations on survival, growth, or reproduction in a chronic wildlife feeding study or a long-term wildlif e field study. If no maximum permissible tissue concentration is available, go to Section X because no Final Residue Value can be derived.
B. Bioconcentration factors (BCFs) and bioaccu mulation factors (BAFs) are quotients of the concentration of a material in one or mo re tissues of an aquatic organism divided by the average concentration in the solution in which the organism had been living. A BCF is intended to account only for net upta ke directly from wate r, and thus almost

25

### has to be measured in a laboratory test. Some uptake during the bioconcentration test might not be directly from water if the food so rbs some of the test material before it is eaten by the test organisms. A BAF is intended to acc ount for the net uptake from both food and water in a real-wor ld situation. A BAF almost has to be measured in a field situation in which predators accumulate the material directly from water and by consuming prey that itself could have accumulated the material from both food and water. The BCF and BAF are probably sim ilar for a material with a low BCF, but the BAF is probably higher than the BCF for materials with high BCFs. Although BCFs are not too difficult to determine, very few BAFs have been measured acceptably because it is necessary to make enough meas urements of the concentration of the material in water to show that it was r easonably constant for a long enough period of time over the range of territory inhabite d by the organisms. Because so few acceptable BAFs are available, only BCFs will be discussed further. However, if an acceptable BAF is available for a material, it should be used instead of any available BCFs. C. If a maximum permissible tissue concentra tion is available for a substance (e.g., parent material, parent material plus metabo lites, etc.), the tissue concentration used in the calculation of the BCF should be for the same substance. Otherwise, the tissue concentration used in the calcu lation of the BCF should be th at of the material and its metabolites which are structurally similar and are not much more soluble in water than the parent material.
D. 1. A BCF should be used only if th e test was flow-through, the BCF was calculated based on measured concentrations of the test material in tissue and in the test solution, and the exposure c ontinued at least until either apparent steady-state or 28 days was reached. Steady-state is reached when the BCF does not change significantly over a peri od of time, such as two days or 16 percent of the length of the exposure, whichever is longer. The BCF used from a test should be the highest of (a) the apparent steady-state BCF, if apparent steady-state was reached, (b) th e highest BCF obtained, if apparent steady-state was not reached, and (c) the projected steady-state BCF, if calculated. 2. Whenever a BCF is determined for a lipophilic material, the percent lipids should also be determined in the tissu e(s) for which the BCF was calculated. 3. A BCF obtained from an exposure that a dversely affected the test organisms may be used only if it is similar to a BCF obtained with unaffected organisms of the same species at lowe r concentrations that did not cause adverse effects. 4. Because maximum permissible tissue con centrations are almost never based on dry weights, a BCF calculated using dry tissue weights must be converted to a wet tissue weight basis. If no co nversion factor is reported with the BCF, multiply the dry weight BCF by 0.1 fo r plankton and by 0.2 for individual species of fishes and invertebrates 17



### .

26

### 5. If more than one acceptable BCF is av ailable for a species, the geometric mean of the available values should be used, except that if the BCFs are from different lengths of exposure and the BCF increases with length of exposure, the BCF for the longest exposure should be used.
E. If enough pertinent data exist, several residue values can be calculated by dividing maximum permissible tissue concen trations by appropriate BCFs: 1. For each available maximum acceptable dietary intake derived from a chronic feeding study or a long-te rm field study with wild life, including birds and aquatic organisms, the appropriate BC F is based on the whole body of aquatic species which constitute or represent a major portion of the diet of the tested wildlife species. 2. For an FDA action level for fish or sh ellfish, the appropriate BCF is the highest geometric mean species BCF for the edible portion (muscle for decapods, muscle with or without skin for fishes, adductor muscle for scallops, and total soft tissue for ot her bivalve molluscs) of a consumed species. The highest species BCF is used because FDA action levels are applied on a species-by-species basis.
F. For lipophilic materials, it might be possible to calculate additional residue values. Because the steady-state BCF for a lipophilic material seems to be proportional to percent lipids from one tissue to another and from one species to another 18 , 19 , 20


### , extrapolations can be made from tested tissues or species to untested tissues or species on the basis of percent lipids. 1. For each BCF for which the percent lipids is known for the same tissue for which the BCF was measured, normalize the BCF to a one percent lipid basis by dividing the BCF by the percent lipids. This adjustment to a one percent lipid basis is intended to make a ll the measured BCFs for a material comparable regardless of the species or tissue with which the BCF was measured. 2. Calculate the geometric mean normalized BCF. Data for both saltwater and freshwater species should be used to determine the mean normalized BCF, unless the data show that the norma lized BCFs are probably not similar. 3. Calculate all possible re sidue values by dividing the available maximum permissible tissue concentrations by the mean normalized BCF and by the percent lipids values appropriate to the maximum permissible tissue concentrations, i.e.,

Residue Value = )lipids percent te(appropria BCF) normalized mean( )ion concentrat tissueepermissibl maximum(

a. For an FDA action level for fish o il, the appropriate percent lipids value is 100.

27

### b. For an FDA action level for fish, th e appropriate percent lipids value is 11 for freshwater criteria a nd 10 for saltwater criteria because FDA action levels are applied on a species-by-species basis to commonly consumed species. The highest lipid contents in the edible portions of important cons umed species are about 11 percent for both the freshwater chinook sa lmon and lake trout and about 10 percent for the saltwater Atlantic herring 21



### .
c. For a maximum acceptable dietary in take derived from a chronic feeding study or a long-term fi eld study with wildlife, the appropriate percent lipids is that of an aquatic species or group of aquatic species which constitute a major portion of the diet of the wildlife species. G. The Final Residue Value is obtained by selecting the lowest of the available residue values. NOTE: 

### In some cases the Final Residue Value will not be low enough. For example, a residue value calculated from an FDA action level will probably result in an average concentration in the edible porti on of a fatty species that is at the action level. Some individual organisms, a nd possibly some species, will have residue concentrations higher than the mean valu e but no mechanism ha s been devised to provide appropriate additiona l protection. Also, some chronic feeding studies and long-term field studies with w ildlife identify concentrations that cause adverse effects but do not identify concentrations which do not cause adverse effects; again no mechanism has been devised to provide appr opriate additional protection. These are some of the species and uses that are not protected at all times in all places.

X. Other Data 

### Pertinent information that could not be used in earlier sections might be available concerning adverse effects on aquatic organisms and their uses. The most important of these are data on cumulative and delaye d toxicity, flavor im pairment, reduction in survival, growth, or reproducti on, or any other adverse eff ect that has been shown to be biologically important. Especially im portant are data for species for which no other data are available. Data from behavioral, biochemical, physiological, microcosm, and field studies might also be available. Data might be available from tests conducted in unusual dilution water (see IV.D and VI.D), from chronic tests in which the concentrations were not measured (see VI.B), from tests with previously exposed organisms (see II.F), and from tests on formulated mixtures or emulsifiable concentrates (see II.D). Such data might a ffect a criterion if th e data were obtained with an important species, the test concentrations were measured, and the endpoint was biologically important.

XI. Criterion 

### A. A criterion consists of two concentrati ons: the Criterion Maximum Concentration and the Criterion Continuous Concentration.

28

### B. The Criterion Maximum Concentration (CMC) is equal to one-half the Final Acute Value. C. The Criterion Continuous Concentration (CCC) is equal to the lowest of the Final Chronic Value, the Final Plant Value, and the Final Residue Value, unless other data (see Section X) show that a lower value shoul d be used. If toxicity is related to a water quality characteristic, the CCC is obtai ned from the Final Chronic Equation, the Final Plant Value, and the Final Residue Value by selecting the one, or the combination, that results in the lowest con centrations in the usua l range of the water quality characteristic, unless other data (s ee Section X) show that a lower value should be used.
D. Round 14 

### both the CMC and the CCC to two significant digits.
E. The criterion is stated as: The procedures described in the "Guideli nes for Deriving Numerical National Water Quality Criteria for the Protection of A quatic Organisms and Their Uses" indicate that, except possibly where a locally important species is very sensitive, (1) aquatic organisms and their uses should not be aff ected unacceptably if the four-day average concentration of (2) does not exceed (3) μ g/L more than once every three years on the average and if the one-hour averag e concentration does not exceed (4) μ g/L more than once every three years on the average. where (1) = insert "freshwater" or "saltwater" (2) = insert name of material (3) = insert the Criteri on Continuous Concentration (4) = insert the Criterion Maximum Concentration.

XII. Final Review 

### A. The derivation of the criterion should be carefully reviewed by rechecking each step of the Guidelines. Items that s hould be especially checked are: 1. If unpublished data are used, are they well documented? 2. Are all required data available? 3. Is the range of acute values for any species greater than a factor of 10? 4. Is the range of Species Mean Acute Values for any genus greater than a factor of 10?
5. Is there more than a factor of te n difference between the four lowest Genus Mean Acute Values? 6. Are any of the four lowest Genus Mean Acute Values questionable?

29

### 7. Is the Final Acute Value reasonable in comparison with the Species Mean Acute Values and Genus Mean Acute Values? 8. For any commercially or recreationally important species, is the geometric mean of the acute values from flow-through tests in which the concentrations of test material were measured lower than the Final Acute Value? 9. Are any of the chronic values questionable? 10. Are chronic values available for acutely sensitive species? 11. Is the range of acute-chronic ratio s greater than a factor of 10? 12. Is the Final Chronic Value reasonable in comparison with the available acute and chronic data? 13. Is the measured or predicted chro nic value for any commercially or recreationally important species below the Final Chronic Value? 14. Are any of the other data important? 15. Do any data look like they might be outliers? 16. Are there any deviations from the Guidelines? Are they acceptable?
B. On the basis of all available pertinent labor atory and field information, determine if the criterion is consistent with sound scientific evidence. If it is not, another criterion, either higher or lower, should be derived using appropriate modi fications of these Guidelines.

30

### 31 

## References

1 U.S. EPA. 1983. Water Quality Standards Regulatio n. Federal Register 48: 51400-51413. November 8.

2 U.S. EPA. 1983. Water Quality Standards Handbook. Of fice of Water Regulations and Standards, Washington, DC.

3 U.S. EPA. 1985. Technical Support Document for Wa ter Quality-Based Toxics Control. Office of Water, Washington, DC.

4 Thurston, C.E. 1962. Physical Characteristics and Chemical Composition of Two Subspecies of Lake Trout. J.

Fish. Res. Ed. Canada 19:39-44.

5 Hodson, P.V., et al. 1983. Effect of Fluctuating Lead Exposure on Lead Accumulation by Rainbow Trout ( Salmo

gairdneri ). Environ. Toxicol. Chem. 2: 225-238.

6 For example, see: Ingersoll, C.G. and R.W. Winner. 1982. Effect on Daphnia pulex (De Geer) of Daily Pulse Exposures to Copper to Cadmium. Environ. Toxicol. Chem. 1:321-327; Seim, W.K., et al. 1984. Growth and Survival of Developing Steelhead Trout ( Salmo gairdneri ) Continuously or Intermittental Exposed to Copper. Can. J. Fish. Aquat. Sci. 41: 433-438; Buckley, J.T., et al. 1982. Chronic Exposure of Coho Salmon to Sublethal Concentrations of Copper-I. Effect on Growth, on Accumulation and Distribution of Copper, and on Copper Tolerance. Comp. Biochem. Physiol. 72C: 15-19; Brown, V.M., et al. 1969. The Acute Toxicity to Rainbow Trout of Fluctuating Concentrations and Mixtures of Ammonia Phenol and Zinc. J. Fish. Biol. 1:1-9; Thurston, R.V., et al. 1981. Effect of Fluctuating Exposures on The Acute Toxicity of Ammonia to Rainbow Trout ( Salmo gairdneri ) and Cutthroat Trout ( S. clarkii ). Water Res. 15: 911-917.

7 For example, see: Horning, W.B. and T.W. Neiheisel. 1979. Chronic Effect of Copper on the Bluntnose Minnow,

Pimephales notatus (Rafinesque). Arch. Environ. Contam. Toxicol. 8:545-552.

8 For example, see: Chapman, G.A. 1982. Letter to Charles E. Stephan. U. S. EPA, Duluth, Minnesota. December 6;

Chapman, G.A. 1975. Toxicity of Copper, Cadmium and Zinc to Pacific Northwest Salmonids. Interim Report. U.S. EPA, Corvallis, Oregon; Sephar, R.L. 19 76. Cadmium and Zinc Toxicity to Flagfish, Jordanelle floridae . J. Fish. Res. Board Can. 33: 1939-1945.

9 U.S. EPA. 1980. Water Quality Criteria Documents; Availability. Federal Register 45: 79318-79379. November

28.

10 U.S. EPA. 1984. Water Quality Criteria; Request for Comments. Federal Register 49: 4551-4554. February 7.

11 Erickson, R.J. and C.E. Stephan. 1985. Calculation of the Final Acute Value for Water Quality Criteria for

Aquatic Organisms. National Technical Information Service, Springfield, Virginia. PB88-214994.

12 U.S. Food and Drug Administration. 1981. Compliance Policy Guide. Compliance Guidelines Branch,

Washington, DC.

13 For good examples of acceptable procedures, see: ASTM Standard E 729, Practice for Conducting Acute Toxicity Tests with Fishes, Macroinvertebrates, and

Amphibians. ASTM Standard E 724, Practice for Conducting Static Ac ute Toxicity Tests with Larvae of Four Species of

Bivalve Molluscs.

14 Huth, E.J., et al. 1978. Council of Biology Editors Style Manual, 4th Ed. Council of Biology Editors, Inc.,

Bethesda, Maryland. p. 117.

15 Dixon, W.J. and M.B. Brown (eds.). 1979. BMDP Biom edical Computer Programs, P-series. University of

California, Berkeley. pp. 521-539.

16 Neter, J. and W. Wasserman. 1974. Applied Linear Statistical Models. Irwin, Inc., Homewood Illinois.17 The values of 0.1 and 0.2 were derived from data published in: McDiffett, W.F. 1970. Ecology 51: 975-988. Brocksen, R.W., et al. 1968. J. Wildlife Management 32: 52-75. Cummins, K.W., et al. 1973. Ecology 54: 336-345. Pesticide Analytical Manual, Volume I, Food and Drug Administration, 1969. Love, R.M. 1957. In: M.E. Brown (ed.), The Physiology of Fishes, Vol. I. Academic Press, New York. p.411. Ruttner, F. 1963. Fundamentals of Limnology, 3rd Ed. Tran s. by D.G. Frey and F.E. J. Fry. University of

Toronto Press, Toronto. Some additional values can be found in:

Sculthorpe, C.D. 1967. The Biology of Aquatic Vascular Plants. Arnold Publishing, Ltd., London.

18 Hamelink, J.L., et al. 1971. A Proposal: Exchange Eq uilibria Control the Degree Chlorinated Hydrocarbons are Biologically Magnified in Lentic Environments. Trans. Am. Fish. Soc. 100:207-214.

19 Lunsford, C.A. and C.R. Blem. 1982. Annual Cycle of Kepone Residue in Lipid Content of the Estuarine Clam,

Rangia cuneata . Estuaries 5: 121-130.

20 Schnoor, J.L. 1982. Field Validation of Water Quality Crite ria for Hydrophobic Pollutants. In; J.G. Pearson, et al.

(eds.), Aquatic Toxicology and Hazard Assessment. ASTM STP 766 . American Society for Testing and Materials, Philadel phia. Pp. 302-315.

21 Sidwell, V.D. 1981. Chemical an d Nutritional Composition of Finfishes, Whales, Cr ustaceans, Mollusks, and Their Products. NOAA Technical Memorandum NMFS F/SEC- 11. National Marine Fisheries Service, Southeast Fisheries Center, Charleston, South Carolina.



### 32

### 33 

## Appendix 1. Resident North American Species of Aquatic Animals Used in Toxicity and Bioconcentation Tests

Introduction 

### These lists identify species of aquatic animals which have repr oducing wild populations in North America and have been used in toxicity or bi oconcentration tests. "N orth America" includes only the 48 contiguous states, Cana da, and Alaska; Hawaii and Puer to Rico are not included. Saltwater (i.e., estuarine and true marine) specie s are considered resident in North America if they inhabit or regularly enter shore waters on or above the continental shelf to a depth of 200 meters. Species do not have to be native to be resident. Unlisted species should be considered resident North American species if they can be si milarly confirmed or if the test organisms were obtained from a wild populat ion in North America. The sequence for fishes is taken from A List of Common and Scientific Names of Fishes from the United States and Canada . For other species, the sequence of phyla, classes, and families is taken from the NODC Taxonomic Code, Third Ed ition, National Oceanog raphic Data Center, NOAA, Washington, DC 20235, July, 1981, and th e numbers given are from that source to facilitate verification. Within a family, genera are in alphabetical order, as are species in a genus. The references given are those us ed to confirm that the species is a resident North American species. (The NODC Taxonomic Code contains foreign as well as North American species.) If no such reference could be found, the species wa s judged to be nonresident. No reference is given for organisms not identified to species; these are considered resident only if obtained from wild North American populations . A few nonresident species are listed in bracket s and noted as "nonresident" because they were mistakenly identifi ed as resident in the past or to save other investigators from doing literature searches on the same species. 

## Special Note
This December 2010 electronic version of the 1985 Guid elines serves to meet the requirements of Section 508 of the Rehabilitation Act. While converting the 19 85 Guidelines to a 508-compliant version, EPA updated the taxonomic nomenclature to reflect changes that occurred since the tables were originally produced in 1985. The numbers included for Phylum, Class and Family represent those currently in use from the Integrated Taxonomic Information System, or ITIS, and reflect what is referred to in ITIS as Taxonomic Serial Numbers. ITIS replaced the National Oceanographic Data Center (NODC) taxonomic coding system which was used to create the original taxonomic tables included in the 1985 Guidelines document (NODC, Third Addition - see Introduction). For more information on the NODC taxonomic codes, see http://www.nodc.noaa.gov/General/CDR-detdesc/taxonomic-v8.html

. The code numbers included in the reference column of the tables have not been updated from the 1985 version. These code numbers are associated with the old NODC taxonomic referencing system and are simply replicated here for historical pur poses. Footnotes may or may not still apply. EPA is working on a more comprehensive update to the 1985 Guidelines, including new taxonomic tables which better reflect the large number of aquatic anim al species known to be propagating in U.S. waters.

### Freshwater Species Table 

### Synonyms appear after the official Scientific Name and are marked with an asterisk ( * 

### ). Non-resident species are noted in the Reference column and are marked with a dagger ( † 

### ) Species Class Family Common Name Scientific Name Reference

Phylum: Porifera (46861) Demospongiae 47528 Spongillidae 47691 Sponge Ephydatia fluviatilis P93
Phylum: Cnidaria (48738) Hydra Hydra oligactis E318, P112 Hydrozoa 48739 Hydridae 50844 Hydra Hydra littoralis E321, P112 Phylum: Platyhelminthes (53963) Planarian Dugesia dorotocephala D22 Planarian Dugesia lugubris Dugesia polychroa ‡ D24

Planarian Planaria gonocephala 1 Planariidae 54502

Planarian Polycelis felina § nonresident Turbellaria 53964

Dendrocoelidae 54469 Planarian Procotyla fluviatilis Dendrocoelum lacteum * E334, P132, D63

Phylum: Gastrotricha (57597) Chaetonotida 57822 Chaetonotidae 57823 Gastrotrich Lepidodermella squamata Lepidodermella squamatum * E413

Phylum: Rotifera (58239) Rotifer Philodina acuticornis Y Eurotatoria (Formerly Bdelloidea) 654070 Philodinidae 58266 Rotifer Philodina roseola E487
Rotifer Keratella cochlearis E442, P188 Eurotatoria (Formerly Monogononta) 654070 Brachionidae 58344 Rotifer Keratella sp. 2

Phylum: Annelida (64357) Polychaeta (Formerly Archiannelida) 64358 Aeolosomatidae 68423 Worm Aeolosoma headleyi E528, P284

Lumbriculidae 68440 Worm Lumbriculus variegatus E533, P290

Tubificid worm Branchiura sowerbyi E534, P289, GG Tubificid worm Limnodrilus hoffmeisteri E536, GG Tubificid worm Quistadrilus multisetosus Peloscolex multisetosus * E535, GG

Tubificid worm Rhyacodrilus montanus GG Tubificid worm Spirosperma ferox Peloscolex ferox * GG

Tubificid worm Spirosperma nikolskyi Peloscolex variegatus * E534, GG Clitellata (Formerly Oligochaeta) 568832 Tubificidae 68585

Tubificid worm Stylodrilus heringianus GG

‡ Synonym § Non-resident species



### 34Species Class Family Common Name Scientific Name Reference

Tubificid worm Tubifex tubifex E536, P289, GG Tubificid worm Varichaeta pacifica GG Worm Nais sp. 2 Worm Paranais sp. 2 Naididae 68854
Worm Pristina sp. 2 Clitellata (Formerly Hirudinea) 568832 Erpobdellidea 69438 Leech Erpobdella octoculata Formerly nonresident (BB16)

Phylum: Mollusca (69458) Viviparidae 70304 Snail Campeloma decisum P731, M216
Bithyniidae (Amnicolidae) (Bulimidae) (Hydrobiidae) 70745 Snail Amnicola sp. 2

Snail Goniobasis livescens P732 Snail Elimia virginica Goniobasis virginica * E1137

Snail Leptoxis carinata Nitocris carinata * Mudalia carinata * X, E1137 Pleuroceridae 71541

Snail Nitocris sp. 2 Snail Lymnaea acuminata † nonresident Snail Lymnaea catascopium Lymnaea emerginata * Stagnicola emerginata * M328

Snail Lymnaea elodes Lymnaea palustris * E1127, M351

Snail Lymnaea luteola † nonresident M266 Snail Lymnaea stagnalis E1127, P728, M296 Lymnaeidae 76483

Snail Lymnaea sp. 2 Snail Biomphalaria glabrata Formerly nonresident (M390) Snail Gyraulus circumstriatus P729, M397 Snail Helisoma campanulatum M445 Planorbidae 76591

Snail Helisoma trivolvis P729, M452 Snail Aplexa hypnorum E1126, P727, M373 Snail Physa fontinalis † nonresident M373 Snail Physa gyrina E1126, P727, M373 Snail Physa heterostropha M378 Snail Physa integra P727 Gastropoda 69459

Physidae 76676

Snail Physa sp. 2 Margaritiferidae 79914 Mussel Margaritifera margaritifera E1138, P748, J11

Unionidae (Formerly Amblemidae) 79913 Mussel Amblema plicata AA122 Bivalvia (Pelecypoda) 79118

Unionidae Mussel Anodonta imbecillis J72, AA122



### 35Species Class Family Common Name Scientific Name Reference

Mussel Carunculina parva Toxolasma texasensis * J19, AA122

Mussel Cyrtonaias tampicoenis P759, AA122 79913

Mussel Elliptio complanata J13 Asiatic clam Corbicula fluminea E1159 Corbiculidae 81381 Asiatic clam Corbicula manilensis P749 Fingernail clam Eupera cubensis Eupera singleyi * E1158, P763, G9
Fingernail clam Musculium transversum Sphaerium transversum * M160, G11 Pisidiidae Sphaeriidae * 81388

Fingernail clam Sphaerium corneum G12 Phylum: Arthropoda (82696) Lynceidae 83769 Conchostracan Lynceus brachyurus E580, P344

Sididae 83834 Cladoceran Diaphanosoma sp. 2

Cladoceran Ceriodaphnia acanthina E618 Cladoceran Ceriodaphnia reticulata E618, P368 Cladoceran Daphnia ambigua E607, P369 Cladoceran Daphnia carinata 3 Cladoceran Daphnia cucullata † nonresident Cladoceran Daphnia galeata mendotae E610, P370 Cladoceran Daphnia hyalina 4 Cladoceran Daphnia longispina 5 Cladoceran Daphnia magna E605, P367 Cladoceran Daphnia parvula E611 Cladoceran Daphnia pulex E613, P367 Cladoceran Daphnia pulicaria A Cladoceran Daphnia similis E606, P367 Cladoceran Simocephalus serrulatus E617, P370 Daphniidae 83872

Cladoceran Simocephalus vetulus E617, P370 Cladoceran Moina macrocopa E622, P372 Moinidae (Formerly Daphnidae) 84162 Cladoceran Moina rectirostris E623 Bosminidae 83935 Cladoceran Bosmina longirostris E624, P373 Branchiopoda (Formerly Crustacea) 83687

Polyphemidae 83959 Cladoceran Polyphemus pediculus E599, P385
Ostracod Cypretta kawatai † nonresident U Ostracoda (Formerly Crustacea) 84195 Cyprididae Cypridae * 84462 Ostracod Cypridopsis vidua E770, P430 Diaptomidae 85779 Copepod Eudiaptomus padanus † nonresident

Temoridae 85855 Copepod Epischura lacustris E751, P407
Copepod Cyclops abyssorum † nonresident Copepod Cyclops bicuspidatus E807, P405 Copepod Cyclops vernalis E804, P405 Maxillopoda (Formerly Crustacea) 621145

Cyclopidae 88634

Copepod Cyclops viridis Acanthocyclops viridis * E803, P397



### 36Species Class Family Common Name Scientific Name Reference

Copepod Acanthocyclops sp. 2 Copepod Diacyclops sp. 2 Copepod Eucyclops agilis P403 Copepod Mesocyclops leuckarti E812, P403 Isopod Asellus aquaticus † nonresident (I2) Isopod Caecidotea bicrenata ( Formerly Asellus bicrenata) HH (I1,2) Isopod Asellus brevicaudus E875, P447, I Isopod Asellus communis E875, P448, I Isopod Asellus intermedius E875, P448, I Isopod Asellus meridionalis † Asellus meridianus * † nonresident
Isopod Asellus racovitzai P449, I Asellidae 92657

Isopod Lirceus alabamae P875, I Crangonyctidae (Formerly Gammaridae) 95080 Amphipod Crangonyx pseudogracilis P459, T68, FF23

Amphipod Gammarus fasciatus E877, P458, T53 Amphipod Gammarus lacustris E877, P458, FF23 Amphipod Gammarus pseudolimnaeus E877, P458, T48 Amphipod Gammarus pulex † nonresident Amphipod Gammarus tigrinus L51, FF17 Gammaridae 93745

Amphipod Gammarus sp. 2 Hyalellidae (Talitridae) 94022 Amphipod Hyalella azteca Hyalella knickerbockeri * E876, P457, T154

Prawn Macrobrachium lamarrei † nonresident Prawn Macrobrachium rosenbergii 6 Palaemonidae 96213
Prawn Palaemonetes kadiakensis E881, P484 Crayfish Cambarus latimanus E897 Crayfish Faxonella clypeata E890 Crayfish Orconectes immunis E894, P482 Crayfish Orconectes limosus E893, P482 Crayfish Orconectes propinquus E894, P482 Crayfish Orconectes nais E894 Crayfish Orconectes rusticus E893, P482 Crayfish Orconectes virilis E894, P483 Crayfish Pacifastacus trowbridgii E883 Crayfish Procambarus acutus P482 Crayfish Procambarus clarki Procambarus clarkii * E885, P482
Crayfish Procambarus simulans E888, P482 Malacostraca (Formerly Crustacea) 89787

Cambaridae (Formerly Astacidae) 97336

Crayfish Procambarus sp. 2 Mayfly Maccaffertium ithaca Stenonema ithaca * S173, O205 Heptageniidae 100504 Mayfly Maccaffertium modestum Stenonema rubrum * S178, O205 Insecta 99208

Baetidea Mayfly Callibaetis skokianus S116, N9



### 37Species Class Family Common Name Scientific Name Reference

Mayfly Callibaetis sp. 2 100755 Mayfly Cloeon dipterum O173 Leptophlebiidae 101095 Mayfly Paraleptophlebia praepedita S89, O233
Mayfly Drunella doddsii Ephemerella doddsi * O245
Mayfly Drunella grandis Ephemerella grandis * O245
Mayfly Ephemerella subvaria N9, O248, S71 Ephemerellidae 101232

Mayfly Ephemerella sp. 2 Caenidea 101467 Mayfly Caenis diminuta S51, O268
Mayfly Ephemera simulans S36, N9, O283 Mayfly Hexagenia bilineata N9, S39, O290 Mayfly Hexagenia rigida O290, S41, N9 Ephemeridae 101525

Mayfly Hexagenia sp. 2 Libellulidae 101797 Dragonfly Pantala hymenaea Pantala hymenea * N15, V603
Damselfly Enallagma aspersum DD Damselfly Ischnura elegans † nonresident Damselfly Ischnura verticalis N15, E918 Coenagrionidae Agrionidae * Coenagriidae * 102077 Damselfly Ischnura sp. 2 Stonefly Pteronarcella badia L172 Stonefly Pteronarcys californica L173 Stonefly Pteronarcys dorsata E947 Pteronarcyidae (Formerly Pteronarcidae) Pleronarcyidae * 102470 Stonefly Pteronarcys sp. 2 Nemouridae 102517 Stonefly Nemoura cinerea † nonresident
Stonefly Acroneuria lycorias N4, E953 Stonefly Acroneuria pacifica E953, L180 Stonefly Claassenia sabulosa E953 Perlidae 102914

Stonefly Agnetina capitata Neophasganophora capitata * Phasganophora capitata * E953, CC407

Perlodidae 102994 Stonefly Skwala americana Arcynopteryx parallela * E954

Nepidae 103747 Water Scorpion Ranatra elongate † (Species cannot be confirmed in ITIS) nonresident

Dytiscidae 111963 Beetle - 2

Elmidae Elminthidae * 114093 Beetle Stenelmis sexlineata W21

Caddisfly Arctopsyche grandis L251, II98 Caddisfly Hydropsyche betteni N24 Caddisfly Hydropsyche californica L253 Hydropsychidae 115398

Caddisfly Hydropsyche sp. 2 Caddisfly Clistoronia magnifica II206 Limnephilidae 115933 Caddisfly Philarctus quaeris II272



### 38Species Class Family Common Name Scientific Name Reference

Brachycentridae 116905 Caddisfly Brachycentrus sp. 2
Tipulidae 118840 Crane fly Tipula sp. 2
Ceratopogonidae 127076 Biting midge - 2
Mosquito Aedes aegypti EE3 Culicidae 125930 Mosquito Culex pipiens EE3 Midge Chironomus plumosus Tendipas plumosus * L423
Midge Chironomus tentans Q Midge Chironomus thummi † nonresident Midge Chironomus sp. 2 Midge Paratanytarsus parthenogeneticus 7 Chironomidae 127917

Midge Paratanytarsus dissimilis Tanytarsus dissimilis * R11

Athericidae (Formerly Rhagionidae) Leptidae * 130928 Snipe fly Atherix sp. 2

Phylum: Ectoprocta (155470) Pectinatellidae (Formerly Pectinatelcidae) 156729 Bryozoan Pectinatella magnifica E502, P269

Lophopodidae 156714 Bryozoan Lophopodella carteri E502, P2671 Phylactolaemata 156688

Plumatellidae 156690 Bryozoan Plumatella emarginata E505, P272

Phylum: Chordata (158852) Agnatha 159693 Petromyzontidae 159697 Sea lamprey Petromyzon marinus F11
Anguillidae 161125 American eel Anguilla rostrata F15

Pink salmon Oncorhynchus gorbuscha F18 Coho salmon Oncorhynchus kisutch F18 Sockeye salmon Oncorhynchus nerka F19 Chinook Salmon Oncorhynchus tshawytscha F19 Mountain whitefish Prosopium williamsoni F19 Golden Trout Oncorhynchus aguabonita ( Formerly Salmo aguabonita) F19

Cutthroat trout Oncorhynchus clarki ( Formerly Salmo clarki) F19

Rainbow trout Steelhead trout * Oncorhynchus mykiss ( Formerly Salmo gairdneri) F19

Atlantic salmon Salmo salar F19 Brown trout Salmo trutta F19 Brook trout Salvelinus fontinalis F19 Actinopterygii (Formerly Osteichthyes) 161061 Salmonidae 161931

Lake trout Salvelinus namaycush F19



### 39Species Class Family Common Name Scientific Name Reference

Esocidae 162137 Northern pike Esox lucius F20

Chiselmouth Acrocheilus alutaceus F21 Longfin dace Agosia chrysogaster F21 Central stoneroller Campostoma anomalum F21 Goldfish Carassius auratus F21 Common carp Cyprinus carpio F21 Zebra danio Zebrafish * Danio rerio † Brachydanio rerio * † nonresident F96 Silverjaw minnow Notropis buccatus Ericymba buccata * F21

Golden shiner Notemigonus crysoleucas F23 Pugnose shiner Notropis anogenus F23 Emerald shiner Notropis atherinoides F23 Striped shiner Luxilus chrysocephalus Notropis chrysocephalus * F23

Common shiner Luxilus cornutus Notropis cornutus * F23
Pugnose minnow Opsopoeodus emiliae Notropis emiliae * F24
Spottail shiner Notropis hudsonius F24 Red shiner Cyprinella lutrensis Notropis lutrensis * F24
Spotfin shiner Cyprinella spiloptera Notropis spilopterus * F25

Sand shiner Notropis stramineus F25 Steelcolor shiner Cyprinella whipplei Notropis whipplei * F25
Northern redbelly dace Phoxinus eos F25 Bluntnose minnow Pimephales notatus F25 Fathead minnow Pimephales promelas F25 Northern squawfish Ptychocheilus oregonensis F25 Blacknose dace Rhinichthys atratulus F25 Speckled dace Rhinichthys osculus F25 Bitterling Rhodeus sericeus F26 Rudd Scardinius erythrophthalmus F26 Creek chub Semotilus atromaculatus F26 Pearl dace Margariscus margarita Semotilus margarita * F26 Cyprinidae 163342

Tench Tinca tinca F26 White sucker Catostomus commersoni F26 Catostomidae 163892 Mountain sucker Catostomus platyrhynchus F26 Black bullhead Ameiurus melas Ictalurus melas * F27

Yellow bullhead Ameiurus natalis Ictalurus natalis * F27

Brown bullhead Ameiurus nebulosus Ictalurus nebulosus * F27 Ictaluridae 163995

Channel catfish Ictalurus punctatus F27



### 40Species Class Family Common Name Scientific Name Reference

Clariidae 164118 Walking catfish Clarias batrachus F28
Adrianichthyidae (Formerly Oryziidae) 165623 Medaka Oryzias latipe † nonresident F96

Banded killifish Fundulus diaphanus F33 Cyprinodontidae 165629 Flagfish Jordanella floridae F33 Mosquitofish Gambusia affinis F33 Amazon molly Poecilia formosa F34 Sailfin molly Poecilia latipinna F34 Molly Poecilia sp. Guppy Poecilia reticulata (Lebistes reticulatus, Obs. ) F34 Poeciliidae 165876

Southern platyfish Xiphophorus maculatus F34 Brook stickleback Culaea inconstans F35 Threespine stickleback Gasterosteus aculeatus F35 Gasterosteidae 166363 Ninespine stickleback Pungitius pungitius F35 White perch Morone americana (Roccus americanus, Obs. ) F36 Percichthyidae 170315 Striped bass Morone saxatilis (Roccus saxatilis, Obs. ) F36

Rock bass Ambloplites rupestris F38 Green sunfish Lepomis cyanellus F38 Pumpkinseed Lepomis gibbosus F38 Orangespotted sunfish Lepomis humilis F38 Bluegill Lepomis macrochirus F38 Longear sunfish Lepomis megalotis F38 Redear sunfish Lepomis microlophus F38 Smallmouth bass Micropterus dolomieui F39 Largemouth bass Micropterus salmoides F39 White crappie Pomoxis annularis F39 Centrarchidae 168093

Black crappie Pomoxis nigromaculatus F39 Rainbow darter Etheostoma caeruleum F39 Johnny darter Etheostoma nigrum F40 Orangethroat darter Etheostoma spectabile F40 Yellow perch Perca flavescens F41 Percidae 168356

Walleye Sander vitreus Stizostedion vitreum vitreum * F41

Sciaenidae 169237 Freshwater drum Aplodinotus grunniens F45

Oscar Astronotus ocellatus F47 Blue tilapia Tilapia aurea F47 Cichlidae 169770 Mozambique tilapia Oreochromis mossambicus Tilapia mossambica * F47

Cottidae 167196 Mottled sculpin Cottus bairdi F60
Bullfrog Rana catesbeiana B206 Amphibia 173420 Ranidae 173433 Green frog Rana clamitans B206



### 41

### 42 Species Class Family Common Name Scientific Name Reference

Pig frog Lithobates grylio Rana grylio * B206
River frog Rana heckscheri B206 Leopard frog Rana pipiens B205 Wood frog Rana sylvatica B206 Frog Rana temporia † nonresident Leopard frog Lithobates sphenocephalus sphenocephalus ( Formerly Rana spenocephala) JJ

Microhylidae 173465 Eastern narrowmouthed toad Gastrophryne carolinensis B192

American toad Anaxyrus americanus americanus Bufo americanus * B196

Toad Bufo bufo † nonresident Green toad Anaxyrus debilis debilis Bufo debilis * B197

Fowler's toad Anaxyrus fowleri Bufo fowleri * B196
Red-spotted toad Anaxyrus punctatus Bufo punctatus * B198 Bufonidae 173471

Woodhouse's toad Anaxyrus woodhousii woodhousii Bufo woodhousii * B196
Northern cricket frog Acris crepitans B203 Southern gray treefrog Hyla chrysoscelis B201 Spring creeper Pseudacris crucifer Hyla crucifer * B202
Barking treefrog Hyla gratiosa B201 Squirrel treefrog Hyla squirella B201 Gray treefrog Hyla versicolor B200 Hylidae 173497

Northern chorus frog Pseudacris triseriata B202 Pipidae 173547 African clawed frog Xenopus laevis Z16
Spotted salamander Ambystoma maculatum B176 Mexican axolotl Ambystoma mexicanum † nonresident Ambystomatidae 173588
Marbled salamander Ambystoma opacum B176 Salamandridae 173613 Newt Notophthalmus viridescens Triturus viridescens * B179


### Footnotes for Freshwater Species

1 Apparently this is an outdated name (D19, 20). Organisms iden tified as such should only be used if they were obtained from North America.

2 Apparently this is an outdated name (D19, 20). Organisms iden tified as such should only be used if they were obtained from North America.

3 If from North America, it is resident and should be called D. similis (C). If not from North America, it should be considered nonresident.

4 If from North America, it is resident and ma y be any one of a number of species such as D. laevie , D. dubia , or D. galeate mendoca (C). If not from North America, it should be considered nonresident.5 If from North America, it is resident and ma y be any one of a number of species such as D. ambigua , D. longiremis , or D. rosea (C). If not from North America, it should be considered nonresident.

6 This species might be established in portions of the southern United States.

7 The taxonomy of this species and this and similar genera has not been clarified, but this sp ecies should be considered reside nt. 

### References for Freshwater Species A) Brandlova, J., Z. Brandl, and C.H. Fernando. 1972. The Cladocera of Ontario with remarks on some species and distribution. Can. J. Zool. 50: 1373-1403. B) W. F., et al. 1968. Vertebrates of the United States. 2nd Ed. McGraw-Hill, New York. C) Brooks, J.L. 1957. The Systematics of North American Daphnia. Memoirs of the Connecticut Academy of Arts and Sciences, Vol. XIII. D) Kenk, R. 1972. Freshwater Planarians (Turbellaria) of North America. Biota of Freshwater Ecosystems Identification Manual No. 1. U.S. G.P.O #5501-0365. E) Edmondson, W.T. (ed.) 1965. Fresh-water Biology. 2nd Ed. Wiley, New York. F) Committee on Names of Fishes. 1980. A List of Common and Scientific Names of Fishes from the United States and Canada. 4th Ed. Special Publication No. 12. American Fisheries So ciety. Bethesda, MD. G) Burch, J.B. 1972. Freshwater Sphaeriacean Clams (Mollusca: Pelecy poda) of North Am erica. Biota of Freshwater Ecosystems Identification Manual No. 3. U.S. G.P.O. #5501-0367. H) N. 1972. Freshwater Polychaet es (Annelida) of North America. Biota of Freshwater Ecosystems Identification Manual No. 4. U.S. G.P.O. #5501-0368. I) Williams, W. D. 1972. Freshwater Isopods (Asellidae) of North America. Biota of Freshwater Ecosystems Identification Manual No. 7. U.S. G.P.O. #5501-0390. J) Burch, J. B. 1973. Freshwater Unionacean Clams (Mollusca: Pelecy poda) of North America. Biota of Freshwater Ecosystems Identification Ma nual No. 11. ‘U.S. G.P.O. #5501-00588. K) Kudo, R. R. 1966. Protozoology. 5th Ed. Thomas, Springfield, Illinois. L) Usinger, R. L. 1956. Aquatic Insects of Calif ornia. University of Ca lifornia Press, Berkeley. M) Clarke, A. H. 1973. The Freshwater Molluscs of the Canadian Interior Basin. Malacologia 13: l-509. N) Hilsenhoff, W.L. 1975. Aquatic Insects of Wisconsin. Technical Bulletin No. 89. Dept. of Natural Resources. Madison, Wisconsin. O) Edmunds, G. F., Jr., et al. 1976. The Mayflies of North and Central America. University of Minnesota Press, Minneapolis. P) Pennak, R. W. 1978. Fresh-Water Invertebrates of the United States. 2nd Ed. Wiley, New York. Q) Wentsell, R., et al. 1977. Hydrobiologia 56: 153-156. R) Johannsen, O.A. 1937. Aquatic Diptera. Part IV. Chironomidae: Subfamily Chironominal. Memoir 210. Cornell Univ. Agricultural Experimental Station, Ithaca, NY. S) Burks, B.D. 1953. The Mayflies, or Ephemeroptera, of Illinois. Bulletin of the Natural History Survey Division. Urbana, Illinois.



### 43

### 44 T) Bousfield, E.L. 1973. Shallow-Water Gammaridean Amphipods of New England. Cornell University Press, Ithaca, New York. U) Sohn, I. G., and L. S. Kornicker. 1973. Morphology of Cypretta kawatai Sohn and Kornicker, 1972 (Crustacea, Ostracoda), with a Discu ssion of the Genus. Sm ithsonian Contributions to Zoology, No. 141. V) Needham, J. G., and M. J. Westfall, Jr. 1955. A Ma nual of the Dragonflies of North America. Univ. of California Press, Berkeley. W) Brown, H. P. 1972. Aquatic Dryopoid Beetles (Coleoptera) of the United States. Biota of Freshwater Ecosystems Identification Manual No. 6. U.S.G.P.O. #5501-0370. X) Parodiz, J.J. 1956. Note s on the Freshwater Snail Leptoxis (Mudalia) carinata (Bruguiere). Annals of the Carnegie Museum 33: 391-405. Y) Myers, F.J. 1931. The Distribution of Rotifera on Mount Desert Island. Am. Museum Novitates 494: l-12. Z) National Academy of Sciences. 1974. Amphibians : Guidelines for the breeding, care, and management of laboratory animals. Washington, D.C. AA) Horne, F.R., and S. McIntosh. 1979. Factors Influencing Distribution of Mussels in the Blanco River in Central Texas. Nautilus 94: 119-133. BB) Klemm, D. J. 1972. Freshwater Leeches (Annelida: Hirudinea) of No rth America. Biota of Freshwater Ecosystems Identification Manual No. 8. U.S.G.P.O. #5501-0391. CC) Frison, T. H. 1935; The Stoneflies, or Plecoptera, of I llinois. Bull. Ill. Nat. Histor y Survey, Vol. 20, Article 4. DD) White, A. M. Manuscript. John Carroll University, University Heights, Ohio. EE) Darsie, R.F., Jr., and R.A. Ward. 1981. Identification and Geographical Distribution of the Mosquitoes of North America, North of Mexico. American Mosq uito Control Association, Fresno, California. FF) Holsinger, J.R. 1972. The Freshwater Amphipod Crus taceans (Gammaridae) of No rth America. Biota of Freshwater Ecosystems Identification Manual No. 5. U.S.G.P.O. #5501-0369. GG) Chapman, P. H., et al. 1982. Rela tive Tolerances of Selected Aquatic Oligochaetes to Individual Pollutants and Environmental Factors. Aquatic Toxicology 2: 47-67. HH) Bosnak, A.D., and E.L. Morgan. 1981. Nati onal Speleological Society Bull. 43: 12-18. II) Wiggens, G.B. 1977. Larvae of th e North American Caddisfly Genera (T ricoptera). Univer sity of Toronto Press, Toronto, Canada. JJ) Hall, R. J. and D. Swineford. 1980. Toxic Effects of Endrin and Toxaphene on the Southern Leopard Frog Rana sphenocephala . Environ. Pollut. (S eries A) 23: 53-65.

### 45 Saltwater Species Table 

### Synonyms appear after the official Scientific Name and are marked with an asterisk ( * 

### ). Non-resident species are noted in the Reference column and are marked with a dagger ( † 

### ) Species Class Family Common Name Scientific Name Reference

Phylum: Cnidaria (Coelenterata) (48738) Hydroid Campanularia flexiosa Campanularia flexuosa ** B122, E81
Hydroid Laomedea loveni †† nonresident Campanulariidae 49470

Hydromedusa Phialidium sp. 1 (E81) Hydroza 48739

Campanulinidae 49756 Hydroid Eirene viridula † nonresident

Phylum: Ctenophora (53856) Pleurobrachiidae 53860 Ctenophore Pleurobrachia pileus B218, E162 Tentaculata 53858 Mnemiidae 53915 Ctenophore Mnemiopsis mccradyi C39, I94

Phylum: Nemertea (Rhynchocoela) (57411) Heteronemertea 57438 Lineidae 57443 Nemertine worm Cerebratulus fuscus B252

Phylum: Rotifera (Rotatoria) (58239) Monogononta 58342 Brachionidae 58344 Rotifer Brachionus plicatilis B272

Phylum: Annelida (64357) Phyllodocidae 65228 Polychaete worm Phyllodoce maculata Anaitides maculata * Nereiphylla maculata * E334

Polychaete worm Neanthes arenaceodentata Nereis arenaceodentata * E377
Polychaete worm Neanthes vaali † nonresident Polychaete worm Nereis diversicolor Neanthes diversicolor * E337, F527

Sand worm Nereis virens Neanthes virens * B317, E337, C58 Nereididae (Nereidae) 65870

Polychaete worm Nereis sp. Polychaete worm Ophryotrocha diadema P23 Dorvilleidae 66478 Polychaete worm Ophryotrocha labronica † Ophryotrocha labrunica * † nonresident Spionidae 66781 Polychaete worm Polydora websteri E338
Cirratulidae 67116 Polychaete worm Cirriformia spirabranchia G253

Ctenodrilidae 67217 Polychaete worm Ctenodrilus serratus G275 Capitellidae 67413 Polychaete worm Capitella capitata B358, E337 Polychaeta 64358

Arenicolidae 67500 Polychaete worm Arenicola marina B369, E337

** Synonym †† Non-resident species

### 46 Species Class Family Common Name Scientific Name Reference

Sabellidae 68076 Polycheate worm Eudistylia vancouveri DD
Oligochaete worm Limnodriloides verrucosus Z Oligochaete worm Monopylephorus cuticulatus Z Oligochaeta 68422 Tubificidae 68585 Oligochaete worm Peloscolex gabriellae Tubificoides gabriellae * Z

Phylum: Mollusca (69458) Black abalone Haliotis cracherodii C88, D17 Haliotididae 566897 Red abalone Haliotis rufescens D18 Calyptraeidae 72611 Common Atlantic slippershell Crepidula fornicata C90, D141

Muricidae 73236 Oyster drill Urosalpinx cinerea Urosalpinx cinereus * B646, D179, E264
Melongenidae (Neptuneidae) 74069 Channeled whelk Busycotypus canaliculatus (Formerly Busycon canaliculatum) B655, D223, E264 Gastropoda 69459

Nassariidae (Nassidae) 74102 Mud snail Nassarius obsoletus Nassa obsoleta * Icyanassa obsoleta * B649, D226, E264

Northern horse mussel Modiolus modiolus D434 Blue mussel Mytilus edulis B566, C101, D428, E299 Mytilidae 79451

Mediterranean mussel Mytilus galloprovincialis † nonresident Pectinidae 79611 Bay scallop Argopecten irradians D447
Pacific oyster Crassostrea gigas C102, D456, E300 Eastern oyster Crassostrea virginica D456, E300 Oyster Crassostrea sp. 1 Ostreidae 79866

Oyster Ostrea edulis E300 Cardiidae 80865 Cockle Cerastoderma edule † Cardium edule * † nonresident

Clam Mulinia lateralis D491 Common rangia Rangia cuneata D491, E301 Mactridae 80942 Surf clam Spisula solidissima B599, D489, E301 Clam Macoma inquinata D507 Tellinidae 81032 Bivalve Tellina tenuis † nonresident Quahog clam Mercenaria mercenaria D523, E301 Common Pacific littleneck Protothaca staminea D526 Veneridae 81439 Japanese littleneck clam Tapes philippinarum D527 Bivalvia (Pelecypoda) 79118

Myidae 81688 Soft-shell clam Mya arenaria B602, D536, E302

Phylum: Arthropoda (82696) Merostomata 82698 Limulidae 82701 Horseshoe crab Limulus polyphemus B533, E403, H30
Branchiopoda (Formerly Crustacea) 83687 Artemiidae 83689 Brine shrimp Artemia salina † 2 nonresident Copepod Calanus helgolandicus Q25 Calanidae 85259 Copepod Undinula vulgaris Q29 Copepod Eucalanus elongatus AA Eucalanidae 85299 Copepod Subeucalanus pileatus Eucalanus pileatus * AA Maxillopoda (Formerly Crustacea) 621145

Pseudocalanidae 85351 Copepod Pseudocalanus minutus E447, I155, Q43

### 47 Species Class Family Common Name Scientific Name Reference

Euchaetidae 85524 Copepod Euchaeta marina Q63

Metridinidae (Formerly Metridiidae) 593501 Copepod Metridia pacifica X179, Y

Pseudodiaptomidae 85847 Copepod Pseudodiaptomus coronatus E447, I154, Q101

Temoridae 85855 Copepod Eurytemora affinis E450, I155, Q111

Pontellidae 86038 Copepod Labidocera scotti R157
Copepod Acartia clausi E447 Acartiidae 86083 Copepod Acartia tonsa E447, I154 Copepod Tigriopus californicus J78 Harpacticidae 86329 Copepod Tigriopus japanicus † nonresident Tisbidae 86444 Copepod Tisbe holothuriae BB

Ameiridae (Formerly Canthocamptidae) 86999 Copepod Nitokra spinipes Nitocra spinipe * Q240

Archaeobalanidae (Formerly Balanidae) 89681 Barnacle Semibalanus balanoides Balanus balanoides * B424, E457

Barnacle Balanus crenatus B426, E457 Barnacle Balanus eburneus B424, E457 Balanidae 89599
Barnacle Balanus improvisus B426, E457 Mysid Heteromysis formosa E513, K720 Mysid Americamysis bahia Mysidopsis bahia * U173
Mysid Americamysis bigelowi Mysidopsis bigelowi * E513, K720 Mysidae 89856

Mysid Neomysis sp. 1 Isopod Idotea balthica Idothea baltica * B446, E483 Isopod Idotea emarginata † nonresident Idoteidae 92564
Isopod Idotea neglecta † nonresident Isopod Jaera albifrons † nonresident Isopod Jaera albifrons sensu † nonresident Janiridae 92810 Isopod Jaera nordmanni † nonresident Ampeliscidae 93320 Amphipod Ampelisca abdita E488, L136

Eusiridae (Pontogeneiidae) 93681 Amphipod Pontogeneia sp. 1

Amphipod Gammarus duebeni L56 Amphipod Gammarus oceanicus E489, L50 Amphipod Gammarus tigrinus L51 Amphipod Gammarus zaddachi † nonresident Gammaridae 93745

Amphipod Marinogammarus obtusatus L58 Uristadae (Formerly Lysianassidae) 621432 Amphipod Anonyx sp. 1

Euphausiidae (Thysanopodidae) 95500 Euphausiid Euphausia pacifica M15 Malacostraca (Formerly Crustacea) 89787

Penaeidae Brown shrimp Penaeus aztecus E518, N17

### 48 Species Class Family Common Name Scientific Name Reference

Pink shrimp Penaeus duorarum E518, N17 White shrimp Penaeus setiferus E518, N17 95602

Blue Shrimp Penaeus stylirostris † nonresident Shrimp Leander paucidens † nonresident Prawn Leander squilla † Palaemon elegans * † nonresident

Prawn Macrobrachium rosenbergii 3 Korean shrimp Palaemon macrodactylus T380 Grass shrimp Palaemonetes pugio E521, N59 Palaemonidae 96213

Grass shrimp Palaemonetes vulgaris B500, E521, N56 Hippolytidae 96746 Sargassum shrimp Latreutes fucorum N78
Coon stripe shrimp Pandalus danae T306, W163 Shrimp Pandalus goniurus W163 Pandalidae 96965 Pink shrimp Pandalus montagui B494, E522, W163 Sand shrimp Crangon crangon † nonresident Bay shrimp Crangon franciscorum Crago franciscorum * V176, W164
Shrimp Crangon nigricauda V176, W164 Crangonidae 97106

Sand shrimp Crangon septemspinosa B500, E522 American lobster Homarus americanus B502, E532 Nephropidae (Homaridae) 97307 European lobster Homarus gammarus † nonresident Paguridae 97774 Hermit crab Pagurus longicarpus B514, E537, N125

Rock crab Cancer irroratus B518, E543, N175 Cancridae 98670 Dungeness crab Cancer magister T166, V185, W177 Blue crab Callinectes sapidus B521, C80, E543, N168 Portunidae 98689 Green crab Carcinus maenas C80, E543 Mud crab Eurypanopeus depressus B522, E543, N195 Crab Leptodius floridanus S80 Xanthidae (Pilumnidae) 98748 Mud crab Rhithropanopeus harrisii E543, N187 Shore crab Hemigrapsus nudus CC Varunidae (formerly Grapsidae) 621521 Shore crab Hemigrapsus oregonensis CC
Drift line crab Armases cinereum (Sesarma cinereum) B526, E544, N222 Sesarmidae (formerly Grapsidae) 621520 Crab Sesarma haematocheir † nonresident Ocypodidae 99080 Fiddler crab Uca pugilator B526, E544, N232

Phylum: Echinodermata (156857) Asteroidea 156862 Asteriidae 157212 Starfish Asterias forbesi B728, E578, O392
Ophiuroidea 157325 Ophiothricidae 157792 Brittle star Ophiothrix spiculata O672, T526

Sea urchin Arbacia lixula † nonresident Arbaciidae 157904 Sea urchin Arbacia punctulata B762, E572 Sea urchin Lytechinus pictus T253 Toxopneustidae 157919 Sea urchin Pseudocentrotus depressus † nonresident Echinidae 157940 [chinoderm Paracentrotus lividus † nonresident Echinoidea 157821

Echinometridae 157955 Coral reef echinoid Echinometra mathaei † nonresident [Hawaii only]

### 49 Species Class Family Common Name Scientific Name Reference

Strongylocentrotidae 157965 Sea urchin Strongylocentrotus purpuratus O574, T202

Dendrasteridae 158008 Sand dollar Dendraster excentricus O537, V363

Phylum: Chaetognatha (158650) Sagittoidea 158655 Sagittidae 158726 Arrow worm Ferosagitta hispida Sagitta hispida * E218

Phylum: Chordata (158852) Chondrichthyes 159785 Rajidae 160845 Thornback ray Raja clavata † nonresident
Anguillidae 161125 American eel Anguilla rostrata A15

Atlantic menhaden Brevoortia tyrannus A17 Gulf menhaden Brevoortia patronus A17 Atlantic herring Clupea harengus Clupea harengus harengus * A17
Pacific herring Clupea pallasii Clupea harengus pallasii * A17 Clupeidae 161700

Herring Clupea harengus A17 Northern anchovy Engraulis mordax A18 Engraulidae 553173 Nehu Encrasicholina purpurea † tolephorus purpureus * † nonresident [Hawaii only] Pink salmon Oncorhynchus gorbuscha A18 Chum salmon Oncorhynchus keta A18 Coho salmon Oncorhynchus kisutch A18 Sockeye salmon Oncorhynchus nerka A19 Chinook salmon Oncorhynchus tshawytscha A19 Rainbow trout (Steelhead trout) Oncorhynchus mykiss ( Formerly Salmo gairdneri) A19 Salmonidae 161931

Atlantic salmon Salmo salar A19 Atlantic cod Gadus morhua A30 Gadidae 164701 Haddock Melanogrammus aeglefinus A30 Sheepshead minnow Cyprinodon variegatus A33 Mummichog Fundulus heteroclitus A33 Striped killifish Fundulus majalis A33 Cyprinodontidae 165629

Longnose killifish Fundulus similis A33 Mosquitofish Gambusia affinis A33 Poeciliidae 165876 Sailfin molly Poecilia latipinna A34 Inland silverside Menidia beryllina A34 Atlantic silverside Menidia menidia A34 Atherinidae 165984
Tidewater silverside Menidia peninsulae A34 Threespine stickleback Gasterosteus aculeatus A35 Gasterosteidae 166363 Fourspine stickleback Apeltes quadracus A35 Syngnathidae 166443 Northern pipefish Syngnathus fuscus A36
Percichthyidae 170315 Striped bass Morone saxatilis (Roccus saxatilis, Obs .) A36

Kuhliidae 168083 Mountain bass Kuhlia sandvicensis † nonresident [Hawaii only] Actinopterygii (Formerly Osteichthyes) 161061

Carangidae 168584 Florida Pompano Trachinotus carolinus A43

### 50 Species Class Family Common Name Scientific Name Reference

Sparidae 169180 Pinfish Lagodon rhomboides A45
Spot Leiostomus xanthurus A46 Atlantic croaker Micropogonias undulatus A46 Sciaenidae 169237
Red drum Sciaenops ocellatus A46 Shiner perch Cymatogaster aggregata A47 Embiotocidae 169735 Dwarf perch Micrometrus minimus A48 Pomacentridae 170044 Blacksmith Chromis punctipinnis A48

Cunner Tautogolabrus adspersus A49 Labridae 170477 Bluehead Thalassoma bifasciatum A49 Mullet Aldrichetta forsteri † nonresident Striped mullet Mugil cephalus A49 Mugilidae 170333
White mullet Mugil curema A49 Ammodytidae 171670 Pacific sand lance Ammodytes hexapterus A53
Longjaw mudsucker Gillichthys mirabilis A54 Gobiidae 171746 Naked goby Gobiosoma bosci A54 Cottidae 167196 Tidepool sculpin Oligocottus maculosus A61
Speckled sanddab Citharichthys stigmaeus A64 Bothidae 172714 Summer Flounder Paralichthys dentatus A64 Dab Limanda limanda † nonresident Plaice Pleuronectes platessa † nonresident English sole Parophrys vetulus A65 Pleuronectidae 172859

Winter flounder Pseudopleuronectes americanus A65 Balistidae 173128 Planehead filefish Monacanthus hispidus A66

Tetraodontidae 173283 Northern puffer Sphoeroides maculatus A66

### 51 Footnotes for Saltwater Species

1 Organisms not identified to species are considered resident only if obtained from wild populations in North America.

2 This species should not be used because it might be too atypical.

3 This species might be established in portions of the southern United States.


### References for Saltwater Species A) Committee on Names of Fishes. 1980. A List of Common and Scientific Names of Fishes from the United States and Canada. 4th Ed. Special Publication No . 12. American Fisheries Society, Bethesda, MD. B) Miner, R. W. 1950. Field Book of S eashore Life. Van Rees Press, New York.C) George, D., and J. George. 1979. Marine Life: An Illustrated Encyclopedia of Invertebrates in the Sea. WileyInterscience, New York. D) Abbott, R.T. 1974. American Seashells. 2nd Ed. Van Nostrand Reinhold Company, New York. E) Gosner, K.L. 1971. Guide to Identification of Marine and Estuarine Invertebrates: Cape Hatteras to the Bay of Fundy. Wiley-Interscience, New York; Gosner, K.L. 1979. A Field Guide to the Atlantic Seashore. Houghton Mifflin, Boston. F) Hartmann, O. 1968. Atlas of the Errantiate Polychaetous Annelids from California. Allan Hancock Foundation, University of Southern California, Los Ange les, California. G) Hartmann, O. 1969. Atlas of the Sedentariate Polychaetous Annelids from California. Allan Hancock Foundation, University of Southern California, Los Ange les, California. H) Cooley, N.R. 1978. An Inventory of the Estuarine Fauna in the Vicinity of Pensacol a, Florida. Florida Marine Research Publication No. 31. Florida Department of Natural Resources, St. Petersburg, Florida. I) Zingmark, R.G. (ed.) 1978. An Annotated Checklist of the Biota of the Coasta1 Zone of South Carolina. University of South Carolina Press, Columbia, South Carolina. J) Monk, C.R. 1941. Marine Harpacticoid Copepods from California. Trans. Amer. Microsc. Soc. 60:75-99. K) Wigley, R. , and B.R. Burns. 1971. Distribution and Biology of Mysids (Crustacea, Mysidacea) from the Atlantic Coast of the United States in the NMFS Woods Hole Collection. Fish. Bull. 69(4):717-746. L) Bousfield, E.L. 1973. Shallow-Water Gammaridean Amphipoda of New England. Cornell University Press. Ithaca, New York. M) Ponomareva, L.A. Euphausids of the North Pacific, their Distribution, and Ecology. Jerusalem: Israel Program for Scientific Translations. 1966. Translated from the Russian by S. Nemchonok. TT65-50098. NTIS, Springfield, VA. N) Williams, A.B. 1965. Marine Decapod Crustacean s of the Carolinas. Fish . Bull. 65(1):1-298. O) Hyman, L.H. 1955. The Invertebrates: Ec hinodermata. Vol. IV. McGraw-Hill, New York. P) Akesson, B. 1976. Morphology and Life Cycle of Ophryotrocha diadema , a New Polychaete Species from California. Ophelia 15(1): 23-25. Q) Wilson, C.B. 1932. The Copepods of the Woods Hole Region, Massachusetts. U.S. Nat. Mus. Bull. 158: 1- 635. R) Fleminger, A. 1956. Taxonomic and Distributional Studies on the Epiplanktonic Calanoid Copepods (Crustacea) of the Gulf of Mexico. Dissertation. Harv ard University, Cambridge. S) Menzel, R.W. 1956. Annotated Checklist of the Marine Fauna and Flora of the St. George ’s Sound - Apalachee Bay region, Florida Gulf Coast. Cont rib. No. 61. Fla. Stat e Univ. Ocea nogr. Inst.T) Ricketts, E.F., and J. Calvin. (Revised by Joe1 W. Hedgpeth). 1968. Between Pacific Tides. Stanford University Press, Stanford, California. U) Price, W.W. 1978. Occurrence of Mysidopsis almyra Bowman, M. bahia Molenock and Bowmaniella brasiliensis Bacescu (Crustacea, Mysidacea) from the Eastern Gulf of Mexico. Gulf Res. Reports 6(2): 173- 175. V) Light, S.F. (Revised by R.I. Smith, et a1.). 1961. In tertidal Invertebrates of th e Central California Coast. University of California Pres s, Los Angeles, California. W) Kozloff, E.N. 1974. Keys to the Marine Invertebrates of Puget Sound, the San Juan Archipelago, and Adjacent Regions. University of Washington Press, Seattle, Washington. X) Calcofi Atlas. No.19. California Cooperative Oceani c Fisheries Investigations, State of California Marine Research Committ ee. Pp. 179-185. Y) Brodskii, K.A. 1967. Calanoida of the Far Eastern S eas and Polar Basin of the U.S.S.R. Jerusalem Series, Keys to the Fauna of the U.S.S.R. Zoological Inst., Academy Sciences, U.S.S.R. No. 35. Z) Chapman, P.M., et a1. 1982. Relativ e Tolerances of Selected Aquatic Ol igochaetes to Individual Pollutants and Environmental Factors. Aquatic Toxicology 2: 47-67. AA) Venkataramiak, A., et al. 1982. Studies on Toxicity of OTEC Plant Components on Eucalanus sp. from the Gulf of Mexico. Ocean Science and Engineering. BB) Zingmank, R.G. (ed.). 1978. An Annotated Checklist of the Biota of the Coasta1 Zone of South Carolina. University of South Carolina Press. CC) Thatcher, T.O 1978. The Relative Sensitivity of Pacifi c Northwest Fishes and Invertabrates to Chlorinated Sea Water. In: R.L. Jolley, et al. (eds.), Water Chlorination: Environmenta1 Impact and Health Effects. Vol. 2. Ann Arbor Science Publishers, Ann Arbor, Michigan. p. 341. DD) Young, J.S., et al. 1979. Effects of Copper on the Sabelled Polychaete, Eudistylia vancouveri : I. Concentration Limits for Copper Accumulation. Arch. Environ. Contam. Toxicol. 8: 97-106.



### 52

## Appendix 2. Example Calculation of Final Acute Value, Computer Program, and Printouts

A. Example Calculation



### N = total number of MAVs in data set = 8
Rank MAV ln(MAV) ln(MAV) 2 

### P = R / (N+1) P



### 4 6.4 1.8563 3.4458 0.44444 0.66667
3 6.2 1.8245 3.3290 0.33333 0.57735
2 4.8 1.5686 2.4606 0.22222 0.47140
1 0.4 -0.9163 0.8396 0.11111 0.33333
Sum 4.3331 10.0750 1.11110 2.04875

S 2 

### = 4/)04875.2(11110.1 4/)3331.4(0750.10

2 2



### − − = 87.134

S = 9.3346 L = [ 4.3331 – (9.3346)(2.04875)] / 4 = -3.6978 A = (9.3346) ( 05. 0 ) – 3.6978 = -1.6105
FAV = e -1.6105 

### = 0.1998
B. Example Computer Program in BAS IC Language for Calculating the FAV

10 REM This program calculates the FAV when there are less than 20 REM 59 MAVs in the data set 30 X = 0 40 X2 = 0 50 Y = 0 60 Y2 = 0 70 PRINT "How many MAVs are in the data set?" 80 INPUT N 90 PRINT "What are the four lowest MAVs?" 100 FOR R = 1 TO 4 110 INPUT V



### 53

### 54 120 X = X + LOG(V) 130 X2 = X2 + (LOG(V)) * (LOG(V)) 140 P = R / (N + 1) 150 Y2 = Y2 + P 160 Y = Y + SQR((X2 – X * X / 4)) 170 NEXT R 180 S = SQR((X2 – X * X / 4) / (Y2 – Y * Y / 4)) 190 L = (X – S * Y) / 4 200 A = S * SQR(0.05) + L 210 F = EXP(A) 220 PRINT "FAV = " F 230 END 

### C. Example Printouts from Program

How many MAVs are in the data set? ? 8 What are the four lowest MAVs? ? 6.4 ? 6.2 ? 4.8 ? .4 FAV = 0.1998

How many MAVs are in the data set? ? 16 What are the four lowest MAVs? ? 6.4 ? 6.2 ? 4.8 ? .4 FAV = 0.4365