CT: Organohalogen compounds (OHCs) have been used and still are used extensively as pesticides, flame retardants, hydraulic fluids, and in other industrial applications. These compounds are stable, most often lipophilic, and may therefore easily biomagnify. Today these compounds are found distributed both in human tissue, including breast milk, and in wildlife animals. In the late 1960s and early 1970s, high levels of the polychlorinated biphenyls (PCBs) and the pesticide dichlorodiphenyl trichloroethane (DDT) were detected in the environment. In the 1970s it was discovered that PCBs and some chlorinated pesticides, such as lindane, have neurotoxic potentials after both acute and chronic exposure. Although the use of PCBs, DDT, and other halogenated pesticides has been reduced, and environmental levels of these compounds are slowly diminishing, other halogenated compounds with potential of toxic effects are being found in the environment. These include the brominated flame retardants, chlorinated paraffins (PCAs), and perfluorinated compounds, whose levels are increasing. It is now established that several OHCs have neurobehavioral effects, indicating adverse effects on the central nervous system (CNS). For instance, several reports have shown that OHCs alter neurotransmitter functions in CNS and Ca2+ homeostatic processes, induce protein kinase C (PKC) and phospholipase A2 (PLA2) mobilization, and induce oxidative stress. In this review we summarize the findings of the neurobehavioral and neurochemical effects of some of the major OHCs with our main focus on the PCBs. Further, we try to elucidate, on the basis of available literature, the possible implications of these findings on human health.
S: http://www.ncbi.nlm.nih.gov/pubmed/16686424 (last access: 22 February 2015)
N: 1. organohalogen compound, any of a class of organic compounds that contain at least one halogen (fluorine (F), chlorine (Cl), bromine (Br), or iodine (I)) bonded to carbon. They are subdivided into alkyl, vinylic, aryl, and acyl halides. In alkyl halides all four bonds to the carbon that bears the halogen are single bonds; in vinylic halides the carbon that bears the halogen is doubly bonded to another carbon; in aryl halides the halogen-bearing carbon is part of an aromatic ring; and in acyl halides (also called acid halides) the halogen-bearing carbon is doubly bonded to oxygen.
2. Organic compounds such as pesticides, PCBs, PAHs, organohalogens and mineral hydrocarbons are most often adsorbed to particles or organic matter, a physical condition often caused by the very low water solubility and weak polarity of organic compounds.
3. HOC: This might be an in-house or a non-recognized abbreviation; not to be used alone, to avoid any risk of confusion.
S: 1. EncBrit – http://global.britannica.com/EBchecked/topic/431995/organohalogen-compound (22 February 2015). 2 & 3. TERMIUMPLUS.
SYN: halogenated organic compound, halogenated organic, organohalogen, organo-halogenated compound.
CR: biomass energy