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The pollution was discovered in 1983, when the Krupa river was meant to become a water supply source. The area was sanitized then, but the soil and water are still highly polluted. Traces of PCBs were found in food (eggs, cow milk, walnuts) and Krupa is still the most PCB-polluted river in the world.
Microbial biodegradation is the use of bioremediation and biotransformation methods to harness the naturally occurring ability of microbial xenobiotic metabolism to degrade, transform or accumulate environmental pollutants, including hydrocarbons (e.g. oil), polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), heterocyclic compounds (such as pyridine or quinoline ...
Exposure to the coplanar stereoisomer 3,3',4,4',5,5'-hexabromobiphenyl (but not the non-coplanar stereoisomer) in genetically susceptible mice is known to cause immunotoxicity and disorders related to the central nervous system, and even at doses as low as 2.5 mg/kg, excess neonatal fatalities are observed (LD 50 is from 5–10 mg/kg). [1]
Test results conducted in the fall showed the presence of PCBs, or polychlorinated biphenyls — toxic, man-made chemicals that were banned from being produced in the United States in 1979 ...
Ortho-PCBs may alter hormone regulation through disruption of the thyroid hormone transport by binding to transthyretin. [8] Coplanar PCBs are similar to dioxins and furans, both bind to the aryl hydrocarbon receptor (AhR) in organisms and may exert dioxin-like effects, in addition to the effects shared with non-coplanar PCBs.
At every stage or trophic level, the concentration is higher, because the persistent chemicals are not "burned off" when the higher organism uses the fat of the prey organism to produce energy. Due to bioaccumulation and biomagnification, the species at the top of the trophic pyramid are most vulnerable to dioxin-like compounds.
The degradation rate of many organic compounds is limited by their bioavailability, which is the rate at which a substance is absorbed into a system or made available at the site of physiological activity, [11] as compounds must be released into solution before organisms can degrade them. The rate of biodegradation can be measured in a number ...
A biopesticide is a biological substance or organism that damages, kills, or repels organisms seens as pests. Biological pest management intervention involves predatory, parasitic, or chemical relationships. They are obtained from organisms including plants, bacteria and other microbes, fungi, nematodes, etc.