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Because of their longevity, PCBs are still widely in use, even though their manufacture has declined drastically since the 1960s, when a host of problems were identified. [3] With the discovery of PCBs' environmental toxicity , and classification as persistent organic pollutants , their production was banned for most uses by United States ...
Printed circuit boards are used in nearly all electronic products today. Alternatives to PCBs include wire wrap and point-to-point construction, both once popular but now rarely used. PCBs require additional design effort to lay out the circuit, but manufacturing and assembly can be automated.
Bioremediation of PCBs is the use of microorganisms to degrade PCBs from contaminated sites, relying on multiple microorganisms' co-metabolism. Anaerobic microorganisms dechlorinate PCBs first, and other microorganisms that are capable of doing BH pathway can break down the dechlorinated PCBs to usable intermediates like acyl-CoA or carbon ...
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]
Polychlorinated biphenyl, an organic chlorine compound, now recognized as an environmental toxin and classified as a persistent organic pollutant; Printed circuit board, a board used in electronics; Plenum chamber burning, in some jet engines; Papillary carcinomas of the breast, rare forms of the breast cancers
Monsanto was acknowledged at the time of the settlement to have ceased making PCBs in 1977, though State Impact of Pennsylvania reported that this did not stop PCBs from contaminating people many years later. [13] State Impact of Pennsylvania stated "In 1979, the EPA banned the use of PCBs, but they still exist in some products produced before ...
Expert groups convened by U.S. government agencies and international institutions to review animal and human data related to PCBs have concluded that PCBs are immunotoxic, including the most recent review in February 2013 by the World Health Organization’s International Agency for Research on Cancer (IARC) (Lauby-Secretan et al., 2013 [27 ...
Through-hole (leaded) resistors. In electronics, through-hole technology (also spelled "thru-hole") is a manufacturing scheme in which leads on the components are inserted through holes drilled in printed circuit boards (PCB) and soldered to pads on the opposite side, either by manual assembly (hand placement) or by the use of automated insertion mount machines.