Ecotoxicity value

The added SQS approach assumes that only the anthropogenic added fraction of a natural element in the soil should be managed (Crommentuijn et al. 1997). The added quality standard is derived using ecotoxicity data obtained by subtracting the background values from the ecotoxicity value [EC(D)x] of the tested soils. 

ECOSAR is a freely available software system which matches the structure of a query molecule to one (or more) of its defined chemical class(es). For most classes, aquatic ecotoxicity values are then predicted using available hn-ear correlations between toxicity and hydrophobicity. Row is estimated for the query molecule using KOWWIN (discussed in the chapter by Howard). The most recent version of ECOSAR (used in this study) contains over 150 relationships for approximately 50 chemical classes. For the purposes of assessing ECOSAR for predicting, transformation product toxicity, the structures of each of the chemicals in the data set were entered into the software system and in instances where the query compound was matched to one or more chemical classes, the most potent ecotoxicity estimate for daphnids was selected for comparative purposes. 

Fourteen formulations of chemical alternatives were submitted to EPA under confidentiality and they were assessed based on numerous human health and ecotoxicity endpoints in addition to bioaccumulation potential and environmental persistence. They were also screened for potential exposure to workers, users and the aquatic environment. Where data gaps existed, EPA experts used models and chemical analogs to estimate the hazard for a particular endpoint. The literature and test data reviews were published in the final report, Environmentally Preferable Options for Furniture Fire Safety Low Density Furniture Foam . In addition, each hazard endpoint was ranked with a concern level (High, Moderate or Low) based on the criteria used by the EPA s New Chemicals Program to rate the concern level of new chemicals submitted under the Toxic Substance Control Act (TSCA). As seen in Figure 8.2, where the hazard endpoint rankings are bold, the value is based on experimental data. Where the hazard endpoints are presented in italic font, the value is estimated based on models or chemical analogs. In this way, detailed hazard information was summarized and presented in a clear and concise format. 

Reference toxicological values for HRA for the selected pollutants were obtained from ISS/ISPESL [21] and IRIS [22] databases or derived from animal in vivo studies (rat or mouse) and using appropriate safety factors while PNEC concentrations were obtained from previously selected peer-reviewed freely available databases [23] such as ECOTOX [24], ChemIDPlus advanced [25] and specific reviews. 

The evaluation for aquatic toxicity on daphnids and fish is reported in Tables 12 and 13. Bold values indicate that compounds are out of the model applicability domain (ECOSAR) or that the prediction is not reliable. ECOSAR and ToxSuite are able to predict all the selected compounds while T.E.S.T. fails in prediction for the daphnia toxicity of perfluorinated compounds (PFOS and PFOA). Tables 12 and 13 include also a limited number of experimental results provided by the model training dataset (some data are extracted from USEPA Ecotox database). Predicted results are in agreement for five compounds only (2, 3, 5, 13 and 14) for both endpoints while the predictions for the other compounds are highly variable. 

The United Nations Globally Harmonized System of Classification and Labelling of Chemicals (GHS) includes an internationally standardized guidance procedure on Transformation/Dissolution Protocol (T/DP) for metals and sparingly soluble metal compounds (United Nations, 2007), recently validated by the OECD (Organization for Economic Cooperation and Development). To establish the acute aquatic hazard classification level of a metal-bearing substance under the GHS, data from the T/DP are compared with an acute ecotoxicity reference value (ERV) derived under conditions similar to those of the T/DP. 

The TDI values settle by the EFSA in 2005 (Table 3) were different from those calculated by the Scientific Committee for Toxicity, Ecotoxicity and the Environment (CSTEE) in 1998 [134] based on the phthalate migration from soft PVC toys and child care articles, and the available toxicity studies on animals at that time [117, 122, 135], with the following values DBP (TDI of 100 pg/kg b.w./day), BBP (TDI of 200 pg/kg b.w./day), and DiDP (TDI of 200 pg/kg b.w./day), but they... 

Over the last decade, much interest has been generated in monitoring environmental problems and associated risks of wastes, in particular, wastewaters generated by the pulp and paper industries. A major goal is to reassess the target pollutant levels and consider the use of risk-based discharge permit values rather than the absolute endpoint values. This risk-based approach requires analytical tools that can quantify the ecotoxic characteristics of discharges rather than the absolute concentration of specihc pollutants or the values of lumped pollution parameters such as BOD, COD, and so on. 

In order to check whether the conservatism in the risk assessment is a result of the estimated concentrations (chemistry LOE), the calculated ranges of ISI values based on the 5 and 95 percentile of TBT concentrations are compared by the observed ISI values in the field (Ecotoxicity LOE). If there is a good correspondence between calculated and observed ISI, it can be concluded that the concentrations are a proper basis for the risk calculations as well. Figure 4 presents the comparison between calculated and observed ISI for open waters (A) and Dutch harbours (B). 

Hazard potential for each effluent was calculated using a mathematical formula (the PEEP index) proposed by Costan et al. (1993). This formula integrates the ecotoxic responses of the battery of tests before and after a biodegradation step. Toxicity test endpoint responses are first transformed to toxic units. The product of effluent toxicity and effluent flow (m3/h) gives the toxic loading value. The log 10 value of an effluent s toxic loading corresponds to its PEEP index. In order to rank the effluents a toxicity classification scale is generated (Tab. 11). 

In brief, the PEEP index is a useful HAS to apply in comparative studies of wastewater effluents to assess their ecotoxicity and toxic loading. Some of its advantages include the fact that it considers results from different toxicity tests and endpoints, while integrating all possible antagonistic, additive or synergistic interactions that can occur between toxicants in a complex liquid sample. Furthermore, the use of a single PEEP value becomes very useful for decisionmakers who are then able to take science-based decisions to prioritize corrective actions on industries whose effluents are the most toxic for the aquatic environment. It is also noteworthy to point out that the PEEP index can be applied anywhere with any number or type of tests and endpoints to suit the needs and expertise of laboratories internationally. 

The waste PEEP index formula can be employed with any appropriate number and type of tests depending on laboratory expertise and means (any bioassay can be replaced by another or added to the proposed list). In theory, waste PEEP index values can vary from 0 to infinity. In practice, it has been shown to produce values ranging from 0 to 10, thereby simulating a readily-understandable "waste scale" indicative of ecotoxic impact. 

Results obtained with bioassays on each leachate sample in the prerequisite study or in the WASTOXHAS procedure can be integrated through a waste toxicity scale system indicative of a specific level of ecotoxic impact. The aim of such a system is to convert individual endpoint values of different tests into a unique hazard index, representing the overall toxicity of the tested leachate. 

Table 8. Field scale study - Ecotoxicity of accumulated percolates of a municipal solid waste incinerator bottom ash (BA) and a slag from a second smelting of lead (2SL) from field experiments and their corresponding waste PEEP index values (see Section 5.6 for the detail of calculations).

Waste Procedure L/S ratio Sensitivity of ecotoxicity tests Waste PEEP index value Waste PEEP trend... 

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