1、Designation: E 1242 97 (Reapproved 2008)Standard Practice forUsing Octanol-Water Partition Coefficient to EstimateMedian Lethal Concentrations for Fish Due to Narcosis1This standard is issued under the fixed designation E 1242; the number immediately following the designation indicates the year ofor
2、iginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers a procedure for estimating thefathead m
3、innow (Pimephales promelas) 96-h LC50 of nonre-active (that is, covalently bonded without unsaturated residues)and nonelectrolytic (that is, require vigorous reagents tofacilitate substitution, addition, replacement reactions and arenon-ionic, non-dissociating in aqueous solutions) organicchemicals
4、acting solely by narcosis, also referred to as Meyer-Overton toxicity relationship.21.2 This procedure is accurate for organic chemicals that aretoxic due to narcosis and are non-reactive and non-electrolytic.Examples of appropriate chemicals are: alcohols, ketones,ethers, simple halogenated aliphat
5、ics, aromatics, and aliphaticsubstituted aromatics. It is not appropriate for chemicals whosestructures include a potential toxiphore (that structural compo-nent of a chemical molecule that has been identified to showmammalian toxicity, for example CN is known to be reponsiblefor inactivation of enz
6、ymes, NO2for decoupling of oxidativephosphorylation, both leading to mammalian toxicity). Ex-amples of inappropriate chemicals are: carbamates, organo-phosphates, phenols, beta-gamma unsaturated alcohols, elec-trophiles, and quaternary ammonium salts.2. Referenced Documents2.1 ASTM Standards:3E 729
7、Guide for Conducting Acute Toxicity Tests on TestMaterials with Fishes, Macroinvertebrates, and Amphib-iansE 943 Terminology Relating to Biological Effects and En-vironmental FateE 1023 Guide for Assessing the Hazard of a Material toAquatic Organisms and Their UsesE 1147 Test Method for Partition Co
8、efficient (N-Octanol/Water) Estimation by Liquid Chromatography3. Terminology3.1 Definitions:3.1.1 narcosisa reversible state of stupor, unconscious-ness, or arrested activity produced by the influence of chemi-cals on critical sites within membranes or by disrupting thenormal functioning of certain
9、 proteins by means of nonspecificbinding of organic chemical(s) to hydrophobic sites. Deathresults if exposure is not terminated after a length of timewhich varies with concentration.3.1.2 octanol-water partition coeffcient (Kow)referred toas P in some literature.3.1.3 toxiphorea chemical structure
10、substituent group thatwhen present gives rise to an adverse effect in exposedorganisms.3.2 For definitions of other terms used in this standard, referto Guide E 729, Terminology E 943, and Guide E 1023.4. Summary of Practice4.1 The hydrophobicity of a non-reactive and non-electrolytic organic chemic
11、al as quantified by log of theoctanol-water partition coefficient is substituted into an experi-mentally derived equation and an approximate 96-h log LC50for fathead minnow is calculated. This value is a maximumvalue. The actual LC50 could be lower, but should not behigher.5. Significance and Use5.1
12、 This procedure can be used to limit the need forscreening tests prior to performing a test for estimating theLC50 of a non-reactive and non-electrolytic chemical to thefathead minnow. By eliminating the screening test, fewer fishneed be tested. The time used for preparing and performing the1This pr
13、actice is under the jurisdiction of ASTM Committee E47 on BiologicalEffects and Environmental Fate and is the direct responsibility of SubcommitteeE47.01 on Aquatic Assessment and Toxicology.Current edition approved Feb. 1, 2008. Published February 2008. Originallyapproved in 1988. Last previous edi
14、tion approved in 2003 as E 1242 97(2003).2Lipnick, Robert L., “Validation and Extension of Fish Toxicity QSARs andInterspecies Comparisons for Certain Classes of Organic Chemicals,” QSAR inToxicology and Xenobiochemistry, Elsevier, 1985.3For referenced ASTM standards, visit the ASTM website, www.ast
15、m.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.screening
16、 test can also be saved. The value obtained in thisprocedure can be used as the preliminary estimate of the LC50in a full-scale test.5.2 Estimates can be used to set testing priority of groups ofnon-reactive and non-electrolytic chemicals.5.3 If the estimated value is more than 0.3 times theexperime
17、ntal value, the mechanism of action is probablynarcosis. If less, the effect concentration is considered to reflecta different mechanism of action.5.4 This practice estimates a maximum LC50, that is,non-reactive and non-electrolytic chemicals are at least as toxicas the practice predicts, but may ha
18、ve a lower LC50 if actingby a more specific mechanism. Data on a chemical indicatinga lower toxicity than predicted should be considered suspect oran artifact because of limited solubility of the test material.6. Procedure6.1 Review other toxicity data on the test material to see ifthe test material
19、 is likely to be acutely toxic by a mechanismother than narcosis. Also, review the structure of the testmaterial for toxic substructures. If there are no toxiphorespresent or other data which indicate the non-reactive andnon-electrolytic chemical will be acutely toxic by a mechanismother than simple
20、 narcosis, this procedure will provide amaximum 96-h LC50 estimate or hypothetical narcosis 96-hLC50.6.2 Obtain the octanol-water partition coefficient (Kow), bymeasurement (see Test Method E 1147), from a literaturesource or by estimation based on structure.4Since the Kowvalue is critical to calcul
21、ating the LC50, it is important toobtain a measured value rather than depending completely onliterature or estimation based on structure.6.3 Derive the relationship between the LC50 and Kowin theform:Log LC50 5 a log Kow1 b log cKow1 1! 2 d (1)using the bilinear model of Kubinyi.5,6Calculate the Coe
22、f-ficient of Determination (R2).6.4 Using this relationship, calculate an estimated LC50 foradditional non-reactive and non-electrolytic chemicals forwhich the Kowis known or estimated.6.5 Compare the calculated 96-h LC50 with solubility to besure it is equal to or less than the solubility limit. If
23、 theestimated LC50 is greater than the solubility, the chemical isprobably not lethal at the highest possible dissolved concen-tration in water.7. Report7.1 Report the following information:7.1.1 The coefficients derived using the relationship in 6.3and the coefficient of determination,7.1.2 The est
24、imated 96-h LC50 for a non-reactive andnon-electrolytic chemical of interest based on the derivedrelationship,7.1.3 Sources of data for LC50 and Kowfrom which therelationship was defined,7.1.4 Source of the Kowfor a non-reactive and non-electrolytic chemical of interest,7.1.5 Name and address of the
25、 persons making each deri-vation of the LC50 Kowrelationship and estimates, and7.1.6 Date of the estimates.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised th
26、at determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reappr
27、oved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you f
28、eel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual re
29、prints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).4Great Lakes Water Quality Initiative Technical Support Document for thePr
30、ocedure to Determine Bioaccumulation Factors Appendix A, Procedure forDeriving Recommended Values for Log Kow, EPA-820-B-95-005, 1995.5Kubinyi, H., “Non-Linear Dependence of Biological Activity on HydrophobicCharacter: The Bilinear Model,” Farmaco (Pavia) Ed. Sci., Vol 34, pp. 248276.6Veith, G. D., Call, D. J., and Brooke, L. T., “Structure-Toxicity Relationshipsfor the Fathead Minnow, Pimephales promelas : Narcotic Industrial Chemicals,”Canadian Journal of Fisheries and Aquatic Sciences, Vol 40, 1983, pp. 743748.E 1242 97 (2008)2
