Trace metals and persistent organic pollutants fingerprint on the particle flux in the deep subtropical NE Atlantic.

Particle flux material collected in 2000 m depth in the Northeast Atlantic at 33°N and 22°W was analyzed for trace metals and persistent organic pollutants. Element enrichment factors relative to lithogenic Al were elevated indicating possible anthropogenic contributions for all trace metals except V. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls and the pesticide DDT exhibited median fluxes of 10.40 µg m-2d-1,0.29 µg m-2 d-1, and 0.90 µg m-2 d-1, respectively. Flux composition reflected long range transport, with low molecular weight and low-chlorinated compounds dominating ∑15PAH and ∑23PCB. PAH isomer ratios identified fossil fuel combustion as the main ∑15PAH source. The composition of ∑4DDT suggested inputs of the fresh technical pesticide during high dust intensity periods. Pollutant fluxes showed seasonality linked to export production in the region, as well as a dependence on annual and sub-annual dust input events.

Persistent chlorinated organic contaminants in harbour porpoises from the North Sea, the Baltic Sea and Arctic waters.

Individual chlorinated biphenyls (CBs) and chlorinated pesticides (p,p'-DDT and metabolites, HCHs and HCB) were determined in blubber samples of 40 harbour porpoises (Phocoena phocoena) of different age and sex from the North Sea, the Baltic Sea and Greenland coastal waters. Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were analysed in a selected group of animals. sigma CB concentrations (medians) in North Sea immature specimens were similar (14.9 micrograms/g lipid) to those from the Baltic Sea (17.0 micrograms/g lipid) and exceeding those in Greenland specimens by an order of magnitude (1.3 micrograms/g lipid). The median concentrations (microgram/g lipid) of HCB, p,p'-DDE, p,p'-DDD and gamma-HCH were in the order Greenland < North Sea < Baltic Sea. The highest concentrations of alpha-HCH (0.14 microgram/g lipid) were found in the Greenland population, and p,p'-DDT was detected only in this group. The North Sea and Baltic Sea populations were identified as distinctly separate on the basis of levels and compositions of these contaminants. The ecological risk associated with dioxin-like toxicity was dominated by the CB congeners 118 and 170; the PCDD/Fs were playing only a minor role.

CB pattern in the harbour porpoise: bioaccumulation, metabolism and evidence for cytochrome P450 IIB activity.

Metabolism of chlorobiphenyls (CBs) was studied in harbour porpoise by comparing patterns of CB-X/CB-153 ratios in blood, brain, liver and blubber with the patterns in herring, the main food source. The CBs were classified in five groups, based on the presence/absence of vicinal H-atoms (vic. Hs) in meta,para (m,p) and/or ortho,meta (o,m) positions and the number of ortho-Cl-atoms (ortho-Cls). Plots of CB-X/CB-153 ratios in porpoise tissue vs the ratios in herring appeared to be linear for each CB group in all tissues. Slopes of these plots (metabolic slopes) were used as quantitative indicators of metabolic activity. In this way, activity of PB-type isozymes of the P450 monooxygenase system was apparent: in contrast to existing literature data, harbour porpoise appears to be able to metabolize congeners with m,p vic. Hs, even in the presence of more than 2 ortho-Cls. The presence of 3-MC-type (MC-type) isozymes was also detected. The metabolic slopes were also used as basis for risk assessment. Due to their metabolism the most toxic non-ortho CBs were not present in the tissues at detectable levels. We suggest a risk assessment approach which takes this into account. It is considered to be an alternative and more reliable basis for risk assessment than the use of toxic equivalent factors. The results support the model of equilibrium distribution of CBs in harbour porpoise and the role of blood as central transport medium. The model has been developed for persistent compounds; it appears to hold for metabolizable CB congeners as well.

Toxic chlorobiphenyls in adipose tissue and whole blood of an occupationally/accidentally exposed man and the general population.

Individual polychlorinated biphenyl (CB) congeners in adipose and whole blood tissues of a capacitor manufacture worker (occupational/accidental exposure) and of the general population were determined. Nondestructive sample cleanup and multidimensional gas chromatography-electron capture detection (MDGC-ECD) techniques were applied. Special attention was given to the toxicologically relevant congeners CB-77, CB-126, CB-169, CB-105, CB-114, CB-118, CB-156, CB-167, and CB-189 (IUPAC). Lipid-based tissue contents of sigma CBs were higher in the occupationally/accidentally exposed worker (adipose = 7,000 ng/g; whole blood = 11 ng/g) than in the general population (adipose = 300 ng/g; whole blood = 1.9 ng/g). Among the non-ortho Cl CBs, CB-77 was below detection limit (< 1.0 pg/g). The contents of CB-126 for the capacitor manufacture worker were 2,000 and 3 pg/g, and in the general population were 100 and 2 pg/g for adipose and whole blood, respectively. The corresponding data for CB-169 were 3,500 and 4 for adipose and whole blood, respectively, in the exposed worker, and 40 and 2 for adipose and whole blood, respectively, in the general population. Congeners with highest contents were CB-153, CB-138, CB-180, CB-170, and CB-187. These congeners possess chlorine substitution patterns, making them resistant to metabolism. X/153 ratios suggest that both PB and 3-MC type cytochrome P-450 enzymes were induced in the exposed worker, as well as in the general population.