Environmental Considerations in Biologies Manufacture

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. 

The most dramatic noticeable toxic effect of TBT on the ecosystem (biota) is imposex, and although this was first recorded on European coastlines, it has now been reported throughout the world. This phenomenon appears when only 2 ng 1 of TBT (as Sn) is present in the water. This very low concentration is sufficient to induce changes in the sexual characteristics of marine snails (dog-whelks), leading to sterility and a decline in the population. As in many environmental crises, biological responses provide the earliest evidence of a major disorder. Tremendous efforts were made by the international community on various issues to fully address this problem. Progress was made by paint manufacturers, resulting in considerably reduced releases of these compounds into the environment. 

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