Organochlorine additives

TABLE 11-22. FOUR-BALL TESTING OF MIXED ORGANOSULFUR AND ORGANOCHLORINE ADDITIVES... 

A major difficulty is that so many applicahons employ polymers as though they were readily disposable, despite the fact that they are, in reality, among the more inert of chemical pollutants. In particular, plashc packaging tends to make a single use of a fabricated polymer which is then thrown away. Even when disposed of responsibly, packaging materials are the source of a serious pollution problem. Municipal authorities dispose of such materials by one of two routes, landfilling and incineration, of which the latter cannot be readily used for chlorinated polymers, such as PVC, because of the additional problems caused by organochlorine species in the atmosphere. 

SFE. SFE has been established as the extraction method of choice for solid samples. The usefulness of SFE for soil samples has been demonstrated for carbamate,organophosphorus and organochlorine pesticides. However, SFE is more effective in extracting nonpolar than polar residues. In order to obtain a greater extraction efficiency for the polar residues of imidacloprid, the addition of 20% methanol as modifier is required. Extraction at 276 bar and 80 °C with a solvent consisting of supercritical carbon dioxide modified with methanol (5%) for 40 min gives a recovery of 97% (RSD = 3.6%, n = 10). It is possible to use process-scale SFE to decontaminate pesticide residues from dust waste. ... 

Maximum concentrations of chlordanes in American oysters (Crassostrea virginica) taken in the Gulf of Mexico in 1976 were near 0.1 pg/kg dry weight (Table 13.2). Chlordane concentrations were substantially lower than concentrations of other organochlorines measured in oysters, such as DDT (28 pg/kg) and polychlorinated biphenyls (90 pg/kg), suggesting a need for additional studies on interaction effects of chlordane residues with those of other environmental chemicals (Rosales et al. 1979). 

Loganathan, B.G., S. Tanabe, M. Goto, and R. Tatsukawa. 1989. Temporal trends of organochlorine residues in lizard goby Rhinogobius flumineus from the River Nagaragawa, Japan. Environ. Pollut. 62 237-251. Ludke, J.L. 1976. Organochlorine pesticide residues associated with mortality additivity of chlordane and endrin. Bull. Environ. Contam. Toxicol. 16 253-259. 

This model is the most fitting for the non-metabolized or very slow metabolized organochlorines like dioxin or DDT. We can see that this is an additional step in understanding the dioxin bioaccumulation in ecosystems. 

Organochlorine insecticides and PCBs in sewages, sludges, muds and fish (1978). Organochlorine insecticides and PCBs in water, an addition (1984). HMSO, London. 

Ludke JL. 1976. Organochlorine pesticide residues associated with mortality Additivity of chlordane and endrin. Bull Environ Contain Toxicol 16 253-260. 

Frank R, Braun HE, Stonefield Kl, et al. 1990. Organochlorine and organophosphorus residues in the fat of domestic farm animal species, Ontario, Canada 1986-1988. Food Addit Contam 7(5) 629- 636. 

The organochlorine pesticides are considered persistent chemicals. Degradation is quite slow when compared with other pesticides, and bioaccumulation, particularly in aquatic ecosystems, is well documented. Their mobility in soil depends on the composition of the soil the presence of organic matter favors the adsorption of these chemicals onto the soil particles, whereas adsorption is poor in sandy soils. Once adsorbed, they do not readily desorb. These compounds induce significant abnormalities in the endocrine balance of sensitive animal and bird species, in addition to their adverse impact on humans, and their use is appropriately banned in most areas. 

In addition, chlorine derivatives are important as intermediates in the chemical industry, and there are numerous chlorine-containing pharmaceuticals for which no substitutes are presently available. Furthermore, organochlorine compounds, some very toxic, do occur naturally on a large scale. Clearly, however, we must endeavor to avoid adding unnecessarily to the natural load of toxins as the old adage goes, it is the dose that makes the poison.4 Certainly, problems exist that require an intelligent and chemically informed resolution, but the total ban advocated by some on the use of chlorine and chlorinated compounds is neither necessary nor acceptable. 

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