Ecotoxicity requirements

Low toxicity/ecotoxicity requirements have led to changes during the last few decades in the types of biocides that can be used. Effective activity in the polymer dispersion allied with low mammalian toxicity and the ability to break down on entering the environment are increasingly important prerequisites for a biocide. 

Samples for mercury analysis should preferably be taken in pre-cleaned flasks. If, as required for the other ecotoxic heavy metals, polyethylene flasks are commonly used for sampling, then an aliquot of the collected water sample for the mercury determination has to be transferred as soon as possible into glass bottles, because mercury losses with time are to be expected in polyethylene bottles. 

For most tasks in the trace chemistry of natural waters, voltammetric determination requires preconcentration, because in a group of simultaneously determined ecotoxic heavy metals one usually has levels below 0.1 p,g/l. 

Freshwater media based on the OECD 203 ecotoxicity testing medium for fish and daphnia have been used in all T/DP testing of metals, metal compounds and alloys in the pH range 6-8.5 to date. However, the composition of a marine medium is also given in the T/DP section of the GHS, and by implication, a method for marine T/D testing is open for development and validation. While not currently required for REACH dossiers, T/D data in marine media and attendant classification proposals may be required in the future for marine shipping. 

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. 

The first problem in interpretation of the probable ecotoxicity of a given chemical is selecting those species and possible effects, which are most significant (Duffus, 1986). This requires a knowledge of ecosystems at risk together with an ability to assess the likely toxicity of the chemical from its chemical and physical properties and mammalian effect data that are usually available. 

Global warming Formation of photochemical pollutants Acidification Human toxicity Ecotoxicity (terrestrial and aquatic) Nutrification (eutrophication) Radiation Yes far less energy required Yes less diffusive emissions VOC Yes less energy required... 

As of 1981, when theEuropeanchemicalspolicy was implemented, theEuropean Union required the submission of base set test data for physiochemical, environmental fate, toxicological properties and health effects, and ecotoxicity parameters for new... 

When the REACH system is introduced, it is possible that additional human health and ecotox-icological information could be required for up to 30,000 existing chemicals, which are currently marketed in volumes greater than 1 t/year (t.p.a.). Therefore, QSAR and other computer-based methods for predicting toxicity are expected to play an increasingly important role, not only for the priority setting of chemicals that need further assessment, but also for hazard assessment purposes. As yet no formal procedures have been put in place for the use of QSAR in the REACH system. 

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