Ecotoxicity effects assessment

The product and active substance data requirements under the BPD are detailed in Tables 1-4 and 7. In addition to these data requirements, it is also important to consider the data requirements outlined in the TGDs (2003) where in some case, further data requirements have now been identified, especially in the area of sediment toxicity and marine ecotoxicity. 

From these lists of data requirements. Predicted No Effects Concentrations (PNEC s) will need to be derived for  

The extent of ecotoxicity data requirements is, to some extent, covered by the exposure and fate and behaviour of the active substance and/or substance of concern. This can be seen in the data requirements table, where extensive data are required for biocidal products that have widespread environmental exposure. Fate and behaviour studies will identify the environmental compartment of concern, e.g. if a substance partitions strongly into sediment from the water column. 

From the ecotoxicity studies conducted for freshwater, marine and sediment organisms, the Predicted No Effect Concentration (PNEC) for each compartment can be derived. 

The derivitisation of PNECs for the freshwater and marine environments are derived using the following assessment factors. The freshwater PNEC assessments have been well established. However, it has been recognized that the assessment factors proposed by the new marine risk assessment TGD (in development) is highly conservative. 

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Costan, G. Bermingham, N. Blaise, C. Ferard, J.F. Potential Ecotoxic Effects Probe (PEEP) a novel index to assess and compare the toxic potential of industrial effluents. Environ. Toxic. Water Quality 1993, 8 (1). 

EFFLUENT ASSESSMENT WITH THE PEEP (POTENTIAL ECOTOXIC EFFECTS PROBE)... 

The proposed hazard assessment scheme (HAS) used in Colombia is a ranking system where toxicity data obtained from the application of a test battery enables one to determine the degree of toxicity of liquid samples on a relative basis. Test battery results are then integrated into the Potential Ecotoxic Effects Probe (PEEP) index formula developed by Environment Canada for the comparison of wastewaters (Costan et al., 1993). This index can be applied to evaluate the potential toxicity of industrial and municipal wastewaters, and to assess the effectiveness of toxicity abatement measures for effluents. This procedure is easy to apply and can be used with different batteries of tests (see Chapter 1 of this volume). 

WASTOXHAS is the acronym for WASte ecoTOXic Hazard Assessment Scheme. This method was developed to ensure that unacceptable adverse effects would not arise from landfilled or re-used waste disposal. It is dedicated to assess the long-term leaching hazardous impact of any solid waste containing potentially hazardous substances (e.g., bulk, stabilized, solidified, or vitrified wastes as well as contaminated soils or sediments intended for soil disposal). 

Blaise, C. and J.F. Ferard. 2005. Effluent assessment with the PEEP (potential ecotoxic effects probe) index. In C. Blaise and J.F. Ferard. (eds), Small-scale Freshwater Toxicity Investigations, Vol. 2, pp. 69-87. New York Springer. 

Such simple models need validation and for this reason ETAD is conducting in a field study to investigate some representative dyes (at manufacturing sites and dyehouses) under a project termed Pathways of Colorants to the Environment. The environmental risk posed by a colorant is a function of both its inherent ecotoxicity and the concentrations attained in the environmental compartments. Unlike other substances eg, household detergents) which are emitted continuously, dyes releases result mainly from batch processes and result in spatial and temporal peak emissions. Obviously, short-time concentrations should be compared with acute data on ecotoxicity, whereas long-tom residual concentrations need to be cranpared with chronic effect levels. Because, data on chronic effects are not often available, empirical information serves as a basis for the effects assessment, ie, the extrapolation to a Predicted No Effect Concentration (PNEC). This PNEC value is to be compared with the so-called Predicted Environmental Concentration (PEC) in order to estimate safe levels of residual dye in the environment. Since it is the dissolved state in which a dyes may become biologically available, it is the aquatic environmental compartment which is primarily addressed here. Nonetheless, some consideration of the impact of dyes on sewage and soil is also included. 

Compostability of a plastic article is verified by assessing four characteristics inherent material biodegradability, disintegrability of the article, absence of negative effects on the composting process and the absence of ecotoxic effects of the compost obtained from a feedstock that includes the plastic. 

Additionally, ecotoxicity is assessed through bioassays performed on the compost (or soil) obtained after disintegration of the compostable article. Bioassays are a quick, reliable and economic instrument that allow the verification of the ecotoxicological effects of the overall degraded material, and a rapid comparison among different material formulations. Bioassays are a useful instrument for regulatory purposes and will be discussed in more detail in Chapter 4. 

Once the overall testing pathway highlights an ecotoxicological effect of a specific substance, toxicity data can be used to perform a risk assessment in order to guarantee that any emission, repeated release and prolonged exposure is below the established safety level for the substance. In other words, a risk assessment approach could be applied to verify that the environmental concentration of the hazardous substances, in real usage/treatment/disposal scenarios and conditions, is kept below the concentration able to exert an ecotoxic effect. 

In environmental risk assessment, the objective is to establish the likelihood of a chemical (or chemicals) expressing toxicity in the natural environment. Assessment is based on a comparison of ecotoxicity data from laboratory tests with estimated or measured exposure in the field. The question of effects at the level of population that may be the consequence of such toxicity is not addressed. This issue will now be discussed. 

The development of models incorporating biomarker assays to predict the effects of chemicals upon parameters related to r has obvious attractions from a scientific point of view and is preferable, in theory, to the crude use of ecotoxicity data currently employed in procedures for environmental risk assessment. However, the development of this approach would involve considerable investment in research, and might prove too complex and costly to be widely employed in environmental risk assessment. 

USEtox calculates characterization factors for human toxicity and freshwater ecotoxicity. Assessing the toxicological effects of a chemical emitted into the environment implies a cause-effect chain that links emissions to impacts through three steps environmental fate, exposure, and effects. Linking these steps, a systematic framework for toxic impacts modeling based on matrix algebra was developed to some extent within the OMNIITOX project [10]. USEtox covers two spatial scales, the continental and the global scales. 

USEtox (Rosenbaum et al. 2008 [42]) was used to address the continental scale. It can be applied to assess either ecotoxicity or human toxicity from different pollutants. It calculates characterization factors for human toxicity and freshwater ecotoxicity, taking into account the environmental fate, exposure and effects of the substance. 

ASTER. 1995. ASTER (Assessment Tools for the Evaluation of Risk) ecotoxicity profile. U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory. Mid-Continent Ecology Division. 

Cleuvers M (2003) Aquatic ecotoxicity of pharmaceuticals including the assessment of combination effects. Toxicol Lett 142 185-194... 

Kovacs, T.G. Gibbons, J.S. Trembaly, L.A. O Connor, B.I. Martel, P.H. Vos, R.H. The effects of a secondary treated bleached Kraft mill effluent on aquatic organisms as assessed by short term and long term laboratory tests. Ecotox. Environ. Safe. 1995, 31, 7-22. 

Cleuvers M. (2(X)5). Aquatic Ecotoxicity of Pharmaceuticals Including the Assessment of Combination Effects. In Dietrich D.R., S.F. Webb, and T. Petry (Eds.). Hot Spot Pollutants Pharmaceuticals in the Environment. Elsevier, New York, pp. 189-202. 

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