Ecotoxicity

While glycol ethers can be considered as biodegradable under aerobic conditions, Eckel et al. have stressed that under anaerobic conditions, such as in the groundwater plume emanating from a landfill, these chemicals may persist for many years. In the same way, due to their physico-chemical properties, glycol ethers can act as cosolvents in mixtures with highly hydrophobic contaminants enhancing the solubility, mobility, and hence, the ecotoxicity of these chemicals. 

In instances of spillage or release, not only humans may be concerned, but tbe damage may also affect tbe environment. The following data are required  

The Po/w, tbat is, the distribution coefficient between octanol and water, indicates a possible accumulation in fat. Malodorous or odor intense compounds should also be indicated. 

The symbol LC50 means lethal concentration for 50% of a test population. The symbol EC50 means efficiency concentration for mobility suppression of 50% a test population. The symbol IC50 means inhibition concentration for 50% of a population in a test for respiratory suppression. 

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ECOTOX database (excerpt from search, October 21, 2002) (hllp //u ii u, epa.goy/... 

Bromothiophenes are toxic materials by aU routes. Inhalation toxicity of 2-bromothiophene is significant. Ecotoxicity is also noted for these materials, particularly for 2-bromo-3-methylthiophene. 2-Thiophenecarboxaldehyde and the 3-methyl derivative can cause minor irritation to the skin and eyes of rabbits. The former is a sensitizer to guinea pig skin, the latter is not. 2-Acetylthiophene is toxic in aU modes of contact. Severe exposure causes serious inflammation of the lung, damage to many organs, and depression of the central nervous system. 

Contains information on the toxic effects of5,600 chemicals on more than 2,800 aquatic species of animals and plants, excluding birds, aquatic mammals, and bacteria. Has now been incorporated into ECOTOX Data System. Hours 8 00 a.m. to 4 30p.m. CST, Monday - Friday. 

The ECOTOXicology database is a source for locating single chemical toxicity data for aquatic life, terrestrial plants and wildlife. ECOTOX integrates three toxicology effects databases AQUIRE (aquatic life), PHYTOTOX (terrestrial plants), and TERRETOX (terrestrial wildlife). These databases were created by the U.S. EPA, Office of Research and Development (ORD), and the National Health and Environmental Effects Research Laborator) (NHEERL), Mid-Continent Ecology Division... 

Eastman Chemical Co., 227 Eastman Kodak Company, 227 ECHO , chlorothalonil, 60 ECOTOX Database System, 305 ECOTRIN , asphm, 60... 

A distinct dependence between LAS alkyl chain length and the chronic or long-term toxicity is also shown (see Table 22) [290,291]. As can be seen, the ecotoxicity of LAS for fishes and daphnia increase significantly with increasing alkyl chain length of the LAS homolog. 

As laboratory experiments have shown, the position of the sulfophenyl group on the alkyl chain has great importance for both biodegradation and eco-toxicology [273,292-295]. These experiments further show that LAB catabo-lites (e.g., sulfophenylcarbonic acids) have a significantly lower ecotoxicity than the original surfactant [288,294]. 

Further examinations have been done in the biodegradation ecotoxicity sequence rest (BEST). In this test a realistic diluted effluent of the modified OECD confirmatory test (DIN 38412, part 26) is tested continually on daphnia reproduction over three generations. It can be said that the effluents of an OECD confirmatory plant (feed 10 mg/L LAS), containing nondegraded surfactants and catabolites, have no negative effect on the juvenile and adult daphnia even in the third generation and do not influence their reproduction [296]. 

Recent data on acute ecotoxicity, chronic ecotoxicity, and water biocoenosis toxicity are given in Table 35. 

GL6 Ecotox Phase I Environmental impact assessments (ElAs) for veterinary medicinal product (VMPs) Phase 1... 

GL38 Ecotoxicity Phase II Environmental Impact Assessment (EIAs) for Veterinary Medicinal Products (VMPs) -Phase II... 

Dimitriou, R Castritsi-Catharios, J. Miliou, H. Ecotox. Environ. Safe. 2003, 54, 30. 

The report was peer-reviewed through the European Commission of Toxicity, Ecotoxicity and the Environment (CSTEE) and by individual expert peer reviewers in EU Member States. The authors of the report were P. Floyd, C. Corden, P. Howe, and S. Dobson. 

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. 

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