Distribution of polychlorinated biphenyls (PCBs) and organochlorine pesticides in soils from the East Antarctic coast

Concentrations of hexachlorobenzene (HCB), alpha-, beta- and gamma-hexachlorocyclohexane (HCH) isomers, 6 o,p'-and p,p'-isomers of DDT and 28 PCB congeners have been measured in eleven soil samples and one lichen collected on the Eastern coast of Antarctica from 5 Russian stations. For samples with low concentrations of PCBs (range 0.20-0.41 ng g(-1) dry weight) and pesticides (0.86-4.69 ng g(-1) and 0.11-1.22 ng g(-1) dry weight for HCHs and DDTs, respectively), atmospheric long-range transport from Africa, South America or Australia was suggested as the sole source of contamination. The profile of PCB congeners was dominated by the more volatile tri-, tetra- and penta-PCBs congeners, thus supporting long-range transport hypothesis. Four samples contained moderate levels of PCBs (range 1.98-6.94 ng g(-1) dry weight) and variable concentrations of pesticides (gamma-HCH, p,p'-DDT and o,p'-DDT being the main contaminants). For samples with high concentrations of PCBs (range 90.26-157.45 ng g(-1)) and high concentrations of pesticides, the presence of high molecular weight PCB congeners such as: 153, 180, 187, 170 etc, strongly suggest a local source (biotic) of PCBs rather than atmospheric transport. It is likely that on a local scale, biotic focussing of pollutants, due to bird activities (nesting and excrement) can cause high contamination levels and become more significant than contaminant input via abiotic pathways.     

Status of the Southern Carpathian forests in the long-term ecological research network

Air pollution, bulk precipitation, throughfall, soil condition, foliar nutrients, as well as forest health and growth were studied in 2006–2009 in a long-term ecological research (LTER) network in the Bucegi Mountains, Romania. Ozone (O₃) was high indicating a potential for phytotoxicity. Ammonia (NH₃) concentrations rose to levels that could contribute to deposition of nutritional nitrogen (N) and could affect biodiversity changes. Higher that 50% contribution of acidic rain (pH?<?5.5) contributed to increased acidity of forest soils. Foliar N concentrations for Norway spruce (Picea abies), Silver fir (Abies alba), Scots pine (Pinus sylvestris), and European beech (Fagus sylvatica) were normal, phosphorus (P) was high, while those of potassium (K), magnesium (Mg), and especially of manganese (Mn) were significantly below the typical European or Carpathian region levels. The observed nutritional imbalance could have negative effects on forest trees. Health of forests was moderately affected, with damaged trees (crown defoliation >25%) higher than 30%. The observed crown damage was accompanied by the annual volume losses for the entire research forest area up to 25.4%. High diversity and evenness specific to the stand type’s structures and local climate conditions were observed within the herbaceous layer, indicating that biodiversity of the vascular plant communities was not compromised.     

Organochlorine contaminants in hair of adolescents from Iassy, Romania

Human hair samples (n=42) from Iassy county (Eastern Romania) collected in 2002-2003 from adolescents were analyzed for hexachlorocyclohexane (HCH) isomers, p,p'-DDT and its metabolites, hexachlorobenzene (HCB), chlordane and metabolites and 5 polychlorinated biphenyl (PCB) congeners. Very low levels were found for HCB and oxychlordane (0.8 and 2.5 ng g(-1)) indicating a low usage of these pesticide formulations in the studied area. In case of HCHs, gamma-HCH isomer was measured at higher median concentrations (79 ng g(-1) hair) compared to the beta-HCH isomer (55 ng g(-1)), which generally is the most prevalent from HCHs. The DDTs profile consisted in p,p'-DDE and p,p'-DDT which levels correspond to 81% of sum DDTs. Very high median concentrations measured for p,p'-DDT (192 ng g(-1)) combined with lower values for p,p'-DDE/p,p'-DDT of 0.4 (from 0.20 to 2.0) in all hair samples suggest recent exposure to "fresh" DDT. When gender was considered, significantly higher concentrations for most of the investigated contaminants were found in girls hair compared to boys. Very high levels were found in the present study for HCHs and DDTs compared to samples from Greece, Western Europe and China. In case of PCBs, the levels found in Romanian samples were found to be in the same range compared to other previously published data.     

Cyclodextrins: a new efficient absorbent to treat waste gas streams

Volatile Organic Compounds (VOCs) in the air provoke health and environmental concerns. This paper focuses on the absorption method to treat industrial polluted air loaded with VOCs. The key variable of this treatment being the choice of a suitable liquid absorbent, the aim of this research work is to investigate the effectiveness and the regeneration of a new potential family of absorbent: cyclodextrins (CDs). All CDs derivatives tested are able to decrease the Henry's law constant of toluene: a reduction of volatility up to 95% may be obtained, depending on CD nature and concentration. Moreover, absorption experiments show that beta-CD, which presents the highest absorption ability, is 250 time more efficient than water. The absorption efficiency is not totally correlated with static experiments, suggesting that, in addition to Henry's law constants and inclusion compounds stability, toluene diffusion into such solutions has to be taken into account. It is also to be noted that salt and pH variations seem to have little influence on the absorption capacity of CDs, which may be of great interest for industrial applications. Finally, since production of solid compounds was not observed during these experiments and since temperature decreases the capture ability in a drastic way, regeneration of the washing solution can be achieved by heating the solution in combination with air stripping.     

Levels and distribution of organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers in sediments and biota from the Danube Delta, Romania

Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and analogues, hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB), were measured in sediments and biota (invertebrates, 11 fish species and cormorant tissues) collected in 2001 from the Danube Delta, the biggest European wetland. DDTs were the predominant pollutants in all samples. A high variability in the concentrations of pollutants within the same species was observed and this was related to sampling location, age, length and sex. DDTs were also the main organohalogenated contaminants in cormorant muscle and liver, followed by PCBs, HCHs, HCB and PBDEs. The present levels of DDTs in cormorant tissues are lower than levels measured in cormorant eggs sampled from the Danube Delta in 1982 and 1997, respectively. The variance of delta15N for herbivores was much greater than for carnivores, while carp and bream showed higher delta15N signatures than expected, probably due to a higher dietary proportion of benthos, typically more delta15N enriched relative to pelagic biota.     

Distribution of organochlorine pesticides, polychlorinated biphenyls and alpha-HCH enantiomers in pork tissues

The distribution of HCH isomers, DDT analogues and selected PCB congeners in pork organs collected from the same individuals raised in Romanian farms was investigated. Organochlorine pesticides (HCHs and DDTs) were the principal contaminants in all samples, while PCB concentrations were low, in accordance with previously reported concentrations from Romanian animal farms. The most part of the pollutant load in the body is retained in the adipose tissue, with HCHs ranging between 16 and 27.7 ng/g lipid and with higher concentrations of DDTs ranging between 65.9 and 334.5 ng/g lipid. The highest PCB levels (up to 32 ng/g lipid) were measured in lung and liver. The lipid-normalized concentrations in the brain were lower than in all other tissues due to the presence of the blood-brain barrier or due to a lower proportion of the neutral lipids such as triglycerides. The highest concentrations of DDTs were measured in muscle and fat, with p,p'-DDE being the principal contributor and with a variable contribution of p,p'-DDD and p,p'-DDT. In liver, p,p'-DDD has a higher contribution to the sum DDTs, while in all analyzed livers, the concentration of p,p'-DDT was very low. beta-HCH was the most persistent HCH isomer in all tissues, accounting for 40-97% of sum HCHs. For all animals, the highest concentrations of beta-HCH and HCHs were found in liver, while the lowest HCH concentrations were measured in brain and spinal marrow. Additionally, the distribution of alpha-HCH enantiomers in the tissues was discussed. In all samples (except 2 brain samples), (+) alpha-HCH was depleted and (-) alpha-HCH was enantioenriched. Enantiomeric ratios in brain were the highest measured values between all organs. For all studied animals, ERs increased in the order fat < muscle < liver < brain.     

Monitoring pollution in River Mureş, Romania, part II: metal accumulation and histopathology in fish

As a part of an exposure and effect monitoring conducted along the river Mureş, Western Romania in 2004, the health status of two indigenous fish species, sneep (Chondrostoma nasus) and European chub (Leuciscus cephalus) was investigated upstream and downstream the city of Arad. In fish, histopathology was assessed in liver and gills, and heavy metals (cadmium, copper, lead and zinc) were analyzed in liver samples. In both fish species, histopathological reactions in the gills (epithelial lifting, focal proliferation of epithelial cells of primary and secondary lamellae and resulting fusion of secondary lamellae, hyperplasia and hypertrophy of mucous cells, focal inflammation and necrosis of epithelial cells) were most severe at the two sampling sites upstream Arad city, which were shown to be polluted by copper, cadmium, faecal coliforms and streptococci in a parallel study. At these two sites, also histopathology in the liver of L. cephalus was more prominent than at the two downstream sites. In C. nasus, symptoms in the liver (focal inflammation with lymphocytic infiltrations, macrophage aggregates and single cell necrosis) were also highly pronounced at the sampling site located directly downstream the municipal sewage treatment plant of Arad. With the exception of copper accumulation in L. cephalus caught at the most upstream sampling site, in both fish species cadmium and copper accumulation were exceptionally high and did not differ significantly between the four sampling sites.     

Inter-species differences for polychlorinated biphenyls and polybrominated diphenyl ethers in marine top predators from the Southern North Sea: Part 2. Biomagnification in harbour seals and harbour porpoises

Harbour porpoises (Phocoena phocoena) and harbour seals (Phoca vitulina) were found to differ in the ability to metabolize polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Biomagnification factors (BMFs), calculated between both predators and their prey (sole - Solea solea and whiting - Merlangius merlangus), had a large range of variation (between 0.5 and 91 for PCBs and between 0.6 and 53 for PBDEs). For the higher chlorinated PCBs and the highest brominated PBDEs, the BMF values in adult males were significantly higher than in the juvenile individuals of both species. BMF values of hexa- to octa-PCBs were the highest, suggesting reduced ability to degrade these congeners. Harbour porpoises had higher BMFs for lower chlorinated PCBs and for all PBDEs compared to harbour seals. Other factors, which may influence biomagnification, such as the octanol-water partition coefficients and the trophic level position measured through stable isotope (δ¹⁵N) analysis, were found to be of lesser importance to predict biomagnification in the studied food chain.     

Brominated flame retardants and polychlorinated biphenyls in fish from the river Scheldt, Belgium

Levels of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), and polychlorinated biphenyls (PCBs) were measured in several fish species originating from the river Scheldt (Belgium). Five sampling locations were chosen in a highly industrialized area along the river, while two ponds in the vicinity of the river served as reference sites. The present study is a follow-up of a survey performed in 2000 which reported extremely high levels of PBDEs and HBCDs in eel (Anguilla anguilla) collected from the same region (Oudenaarde, Flanders). The sum of tri- to hepta-BDE congeners (2270+/-2260 ng/g lipid weight (lw), range 660-11500 ng/g lw) and total HBCDs (4500+/-3000 ng/g lw, range 390-12100 ng/g lw) were one order of magnitude higher than levels usually reported from freshwater systems, indicating the presence of point sources. In most samples, levels of total HBCDs were higher than those of PBDEs, probably due to the high density of factories using HBCD as an additive brominated flame retardant (BFR). The high values of HBCDs were confirmed by both gas- and liquid-chromatography-mass spectrometry. Although BFR levels were between the highest ever reported in freshwater ecosystems, PCBs could be detected at even higher concentrations (16000+/-14300 ng/g lw, range 3900-66600 ng/g lw), being among the highest levels recorded in Belgium. The inter-sampling site variation of PBDEs, HBCDs and PCBs was comparable. All locations presented similar PBDE congener profiles, with BDE 47 being the dominant congener, followed by BDE 100, BDE 99 and BDE 49, probably originating from the former use of the penta-BDE technical mixture. In order to estimate the impact of these point sources on human exposure, we further focussed on eels which showed a considerable decrease in the PBDE and HBCD levels between 2000 and 2006. Due to the wide span in concentrations between the different sampling locations, a variable contribution to the total human exposure through local eel consumption was estimated. The calculated daily intake ranged from 3 ng to 330 ng PBDEs/day for normal eel consumers, but was as high as 9800 ng PBDEs/day for anglers, which may be considered at risk.