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Annex 9 Guidance on Hazards to the Aquatic Environment

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Annex 9 Guidance on Hazards to the Aquatic Environment Copyright@United Nations, 2017. All rights reserved A8.5 eerences 1. Patty, (Ed.) 1994). ndustrial Hygiene an oxicology. th Ed. xxx-xx w York: iley- Interscience. 2. Smyth, F., Carpenter, .P., Weil, . and ozzan U. (1954). ange finding xicity data. Arch. nd. Hyg. ccup. ed. 3. Fasey, drick, k d undquis (1987). cute, -day, n -week apour nhalation studies n balen Hazexy Systemol. Fundamental and pplied Toicology. 4. Wyeth, egor, r d ad 1989). valuation of developmen xicity f Globalen Hazexy ystemo n Fischer 344 and w Zealand h abbits. Fundamental and pplied Toicology. 5. Etc. ANNE GUIDAN AZARDS AQUATIC IRONMENT - - Copyright@United Nations, 2017. All rights reserved Annex 9 GUIDANCE ON HAZARDS TO THE AQUATIC ENVIRONMENT Contents Page A9.1 Introduction ..................................................................................................................................... 449 A9.2 The harmonized classification scheme .................................................................................................... 452 A9.2.1 Scope ..................................................................................................................................... 452 A9.2.2 Classification categories and criteria ........................................................................................ 452 A9.2.3 Rationale ................................................................................................................................... 452 A9.2.4 Application ............................................................................................................................... 453 A9.2.5 Data availability ........................................................................................................................ 454 A9.2.6 Data quality .............................................................................................................................. 454 A9.3 Aquatic toxicity ..................................................................................................................................... 455 A9.3.1 Introduction .............................................................................................................................. 455 A9.3.2 Description of tests ................................................................................................................... 455 A9.3.3 Aquatic toxicity concepts ......................................................................................................... 457 A9.3.4 Weight of evidence ................................................................................................................... 459 A9.3.5 Difficult to test substances ........................................................................................................ 459 A9.3.6 Interpreting data quality ............................................................................................................ 465 A9.4 Degradation ..................................................................................................................................... 465 A9.4.1 Introduction .............................................................................................................................. 465 A9.4.2 Interpretation of degradability data .......................................................................................... 466 A9.4.3 General interpretation problems ............................................................................................... 470 A9.4.4 Decision scheme ....................................................................................................................... 472 A9.5 Bioaccumulation ..................................................................................................................................... 473 A9.5.1 Introduction .............................................................................................................................. 473 A9.5.2 Interpretation of bioconcentration data ..................................................................................... 473 A9.5.3 Chemical classes that need special attention with respect to BCF and Kow values ................... 476 A9.5.4 Conflicting data and lack of data .............................................................................................. 478 A9.5.5 Decision scheme ....................................................................................................................... 478 A9.6 Use of QSAR ..................................................................................................................................... 479 A9.6.1 History ..................................................................................................................................... 479 A9.6.2 Experimental artifacts causing underestimation of hazard ....................................................... 479 A9.6.3 QSAR modelling issues ............................................................................................................ 480 A9.6.4 Use of QSARs in aquatic classification .................................................................................... 481 A9.7 Classification of metals and metal compounds ...................................................................................... 483 A9.7.1 Introduction .............................................................................................................................. 483 A9.7.2 Application of aquatic toxicity data and solubility data for classification ................................ 485 A9.7.3 Assessment of environmental transformation ........................................................................... 486 A9.7.4 Bioaccumulation ....................................................................................................................... 487 A9.7.5 Application of classification criteria to metals and metal compounds ..................................... 487 Appendix I Determination of degradability of organic substances ................................................... 491 Appendix II Factors influencing degradability in the aquatic environment ..................................... 497 Appendix III Basic principles of the experimental and estimation methods for determination of BCF and Kow of organic substances ............................................. 501 Appendix IV Influence of external and internal factors on the bioconcentration potential of organic substances ........................................................................................................ 505 Appendix V Test guidelines ................................................................................................................... 507 Appendix VI References ......................................................................................................................... 511 - 447 - - 447 - Copyright@United Nations, 2017. All rights reserved ANNE GUIDANCE ON ARD QUATI NVIRONMENT1 A9.1 Introduction A9.1.1 In eveloping s of iter for entifying ubstances azardous aqu environmen it was reed th d needed roperly efin th hazard environmen esulted complex ystem for which om suitab guidance would necessary. herefore, purpos of is ocument wofold: (a) to provide descriptio of guidance w he ystem will ork; (b) to provide guidance interpretation f for s in plying classification iteria. A9.1.2 Th hazard ification chem h been eveloped with h objec of entifying hose ubstances th presen through intrins properties ey ossess, danger aqua vironmen In his ntex the aqu environmen is en th aqu ecosystem n reshwater nd marine, nd e rganisms h liv in For mos substances, e majority f availab address this nvironmen mpartmen Th definition imited n scop in a do no yet, clud aquat sediments, or igher rganisms th top d f aqua food- chain, hough es may om exten b covered y h criter selected. A9.1.3 Although mited n cope, is widely cepted h this mpartmen is oth vulnerable, h is th fin receiving nvironmen for many armful ubstanc and h organisms a liv ther ar sensitive. I is so complex ince y ystem hat eeks entify hazards environmen mus seek to efin thos effects ms f wider ffects n osystems ather han n ndividu within spec or opulation. As wi b described in th subsequen sections, limited of specific roperties f ubstances av been elected roug which he haza can b described acu aqu toxicity chron u toxicity lack f egradability and otential r tual bioaccumulation. h rationa for selection f hese th means efin th aqu hazard w b described mor d in ction A9.2. A9.1.4 This nex limited this tage, application f h criter to ubstances. h term ubstances covers wid rang of em many f which os difficul alleng to classification ystem based n igid criteria. h following ections wi thus rovid som guidance to how h challenges n dea with ased both n xperience n use nd r scientific ationale. hile e armonized iter apply most sily to e classification f individual ubstances f efined structur (see efinition n hapter .2), om materials h f under this category are frequently referred to as “complex mixtures”. In most cases they can be characterized as a homologous ser f substances with certain ang of rbon ain ngth/number r egree f ubstitution. Spec methodologies hav been eveloped or ing which rovid d for aluating h intrins hazard qu organisms, bioaccumulation nd egradation. r specif guidance s rovided separ sections n h
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