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The latitudinal distribution of persistent organic pollutants (POPs: legacy organochlorines [OCs], polybrominated diphenyl ethers [PBDEs,] and hexabromocyclododecane [HBCD]) was examined in livers of two species of marine fish, the pelagic saithe (Pollachius virens,n = 40) and the demersal cod (Gadus morhua,n = 40), along a south-north gradient (59°-70°N) on the Norwegian Coast. Cod had in general two to three times higher concentrations of POPs than saithe, probably because of higher exposure in the benthic food chain. The concentrations of heavy halogenated compounds were higher in the southernmost region than further north. Moreover, the POP pattern showed a gradual shift in the compositions from south to north, especially for OCs in cod: i.e. the relative importance of low-chlorinated polychlorinated biphenyl (PCB) congeners and some OC-pesticides (e.g., hexachlorobenzen [HCB]) in the contaminant burdens increased with latitude. The latitudinal fractionation signal was weaker in saithe, possibly due to its pelagic and nomadic behavior. Hence, this study shows not only a strong latitudinal fractionation in the compositional patterns of POPs in marine fish but also the effects of habitat use and fish behavior. [ABSTRACT FROM AUTHOR]

1-Chloro-2,2-bis(4-chlorophenyl)ethene (p,p'-DDMU), a metabolite of either 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDD) or 1,1-dichloro-2,2-bis(4-chlorophenyl)ethepe (p,p'-DDE), which is degraded from 1 ,11-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDT), was detected in a variety of environmental matrices of the Pearl River Delta (PRD), South China, including fish, fish feeds, semidigested fish stomach contents, marine surface sediment, surface soil, atmospheric gaseous phase, and particulates, rainwater, and coastal rainwater. For fish species, the concentrations of p,p'-DDMU were significantly higher in farmed fish than in marine wild fish, with the highest value obtained in seawater farmed fish species (mean/median values of 262/173 ng/g lipid). The relative abundance of p,p'-DDMU to total DDTs (sum of o,p'- and p,p'-DDT, DDD, and DDE) was higher in samples of marine origin (~5%) than in those of terrestrial origin (~2%). Because p,p'-DDD was considerably abundant in all samples and a negative linear correlation was found between p,p'-DDD/(p,p'-DDD + p,p'-DDE) and p,p'-DDMU/DDTs in the marine sediments r2 = 0.73) and seawater farmed fish (r2 = 0.29) under investigation, it is possible that DDMU was partially dehydrochlorinated from DDD in the environment of the PRD. A fugacity-based assessment suggested that p,p'-DDMU is likely to transport from sediment to seawater and then to air and from soil to air. The ubiquity of p,p'- DDMU in the PRD indicates that it may also be widespread worldwide particularly in countries with large amounts of DDT used currently and/or historically. Given the potential risk of p,p'- DDMU to human health, more efforts should be directed toward to this previously overlooked contaminant. [ABSTRACT FROM AUTHOR]