Semiquantitative Characterization of Bromo-chloro Paraffins and Olefins in the Australian Environment

A semiquantitative high-resolution mass spectrometry method was developed and applied to assess the occurrence of bromo-/chloro paraffins (BCPs) and olefins (BCOs) in the environment. More than 400 possible BCPs and BCO congener groups were detected in dust, air, and sewage sludge samples collected from Australia. Median chain analytes with the number of halogen atoms <7 (C_nH_mCl_xBr_y, 14 ≤ n ≤ 17, x + y < 7) prevailed in the dust and sludge samples, while short chain analytes (C_nH_mCl_xBr_y, 10 ≤ n ≤ 13, x + y < 7) predominated the air samples. The estimated concentrations of ∑BCPs and ∑BCOs in dust and sludge were approximately 20% that of the chlorinated paraffins (CPs) present, with the median concentrations of 5.4 μg/g (dust) and 0.18 μg/g (sludge) for ∑BCPs and 22 μg/g (in dust) and 0.50 μg/g (sludge) for BCOs. In the air samples, the concentrations of BCPs (0.020 pg/m³) and BCOs (0.032 pg/m³) were 3-4 orders of magnitudes lower than the concentrations of CPs (790 pg/m³). Significant correlations (P < 0.001) were found between the concentration of CPs, BCPs, and BCOs in all the matrices.

Tricresyl phosphate and the aerotoxic syndrome of flight crew members--current gaps in knowledge

Tricresyl phosphate (TCP), and in particular its tri-ortho substituted isomer (o,o,o-TCP), has been frequently used in aircraft engine oil. Bleed air, provided to the flight deck and cabin can contain traces of TCP. TCP can cause neurotoxic effects in humans. Regularly, airline pilots complain about loss of memory, headaches, dizziness, tunnel vision and other neurotoxic effects. The concentrations of TCP reported in flight deck air (max. ca. 50-100 ng m(-3) total TCP) do not exceed provisional toxicity thresholds. These thresholds, however, contain a very high uncertainty and need further underpinning. The many non-detects and relatively low TCP concentrations reported suggest that TCP on its own is not likely to be responsible for the reported health problems of pilots. Specific conditions in air planes and other toxic compounds present in bleed air, whether or not in combination with TCP, may be responsible for the reported neurotoxic syndromes. Sensitivity of individuals seems to be an important factor as well. The clinical signs observed with a selected group of pilots are serious enough to call for further elucidation of this issue.

Towards development of a rapid and effective non-destructive testing strategy to identify brominated flame retardants in the plastics of consumer products

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants (BFRs) once extensively used in the plastics of a wide range of consumer products. The listing of certain congeners that are constituents of commercial PBDE mixtures (including c-octaBDE) in the Stockholm Convention and tightening regulation of many other BFRs in recent years have created the need for a rapid and effective method of identifying BFR-containing plastics. A three-tiered testing strategy comparing results from non-destructive testing (X-ray fluorescence (XRF)) (n=1714), a surface wipe test (n=137) and destructive chemical analysis (n=48) was undertaken to systematically identify BFRs in a wide range of consumer products. XRF rapidly identified bromine in 92% of products later confirmed to contain BFRs. Surface wipes of products identified tetrabromobisphenol A (TBBPA), c-octaBDE congeners and BDE-209 with relatively high accuracy (>75%) when confirmed by destructive chemical analysis. A relationship between the amounts of BFRs detected in surface wipes and subsequent destructive testing shows promise in predicting not only the types of BFRs present but also estimating the concentrations present. Information about the types of products that may contain persistent BFRs will assist regulators in implementing policies to further reduce the occurrence of these chemicals in consumer products.

Polybrominated diphenyl ether contamination levels in fish from the Antarctic and the Mediterranean Sea

Polybrominated diphenyl ethers (PBDEs) concentrations and congener profiles were evaluated in four species of Antarctic fish (Chionodraco hamatus, Chaempsocephalus gunnari, Gymnoscopelus nicholsi,Trematomus eulepidotes) and in one Mediterranean species (Tuna, Thunnus thynnus). The GC/MS-ECNI analysis revealed that average sigmaPBDE concentrations in Antarctic fish species ranged from 0.09 ng g(-1)wet weight (wet wt) in G. nicholsi to 0.44 ng g(-1)wet wt in C. gunnari. In Mediterranean tuna they were two or three orders of magnitude higher (15 ng g(-1)wet wt). The PBDE congener profiles differed between species; low brominated congeners prevailed in Antarctic species while in tuna tetra- and pentabromodiphenyl ethers were the most abundant congener groups (41% and 44%, respectively). These results showed that PBDE levels significantly correlated with the length of the fishes (r(2)=0.85, p<0.01) in C. hamatus, but not with the weight of the fish. Moreover, mean sigmaPBDE concentrations in tuna were statistically higher in females than in males (18 and 13 ng g(-1)wet wt, respectively; p<0.05), which was explained by the lower fat contents of the males that just had entered the spawning period. The results of this study confirm that PBDE contamination of the marine environment now occurs on a global scale.

Perfluoroalkyl compounds in relation to life-history and reproductive parameters in bottlenose dolphins (Tursiops truncatus) from Sarasota Bay, Florida, U.S.A

Perfluoroalkyl compounds (PFCs) were determined in plasma, milk, and urine of free-ranging bottlenose dolphins (Tursiops truncatus) from Sarasota Bay (FL, USA) during three winter and two summer capture-and-release programs (2002-2005). Plasma and urine samples were extracted using an ion-pairing method. Perfluoroalkyl compounds were extracted from milk samples using acetonitrile, and extracts were cleaned with graphitized nonporous carbon. All extracts were analyzed by high-performance liquid chromatography-tandem mass spectrometry. Mean seasonal sum of PFCs (sigma PFCs) detected in dolphin plasma ranged from 530 to 927 ng/g wet weight. No significant differences (p > 0.05) were found in concentrations between seasons, suggesting a constant exposure to PFCs. Overall, blubber thickness of dolphins did not correlate with PFC concentrations in plasma, suggesting an absence of PFC sequestration in blubber. Sexually immature calves (age, <10 years; mean sigma PFCs, 1,410 +/- 780 ng/ g wet wt) were significantly more contaminated (p < 0.001) than their mothers (mean sigma PFCs, 366 +/- 351 ng/g wet wt). The reproductive history of females had a significant role in the burden of PFC contamination; PFC concentrations in nulliparous females (females that have not been observed with calves) were significantly greater than those detected in uniparous females (females that have been observed with one calf), suggesting an off-loading of PFCs during or after parturition. To investigate this hypothesis, PFCs were analyzed in milk samples (n=10; mean sigma PFCs, 134 +/- 76.1 ng/g wet wt), confirming a maternal transfer of PFCs through lactation in dolphins. Results from the present study showed that young and developing bottlenose dolphins are highly exposed to PFCs. These chemicals also were detected in urine (mean sigma PFCs, 26.6 +/- 79 ng/g wet wt), indicating that the urinary system is an important pathway of PFC depuration in dolphins.

[The milking machine as a factor in udder health (author's transl)]

The milking machine may increase the hazards of mastitis by direct contact with contaminated teat-cup liners, by erosion of the teat opening or movements of milk and air from the claw in the direction of the teats. Erosion about the teat opening (formation of callous tissue) is very common in commercial herds, though the risks of subclinical mastitis hardly increase in herds showing slightly eroded streak canals. Probably the callousity is caused by the presence of the liners on the teat end. During milking, the teats may be contaminated with pathogens by a reverse flow of milk in the short milk tube caused by the action of the pulsator or by a sudden flow or air against the teats caused by the entry of additional air in the system. This air flow may generate milk droplets which beat against the teats or even penetrate the streak canal ('droplet impacts'). Particularly these 'droplets impacts' are responsible for new udder infections. A differentiation can be made between 'liner impacts', caused by the entry of air in one of the teat cups of the same cluster, and 'milk-tube impacts' generated by a sudden air flow from the long milk tube. Reduction of the former type of impact may be achieved by liners with little air leakage, milking routines without stripping or removal of the clusters without a sudden air inlet. The latter type may be prevented by an adequate vacuum supply of the plant and wide milk lines. The drawbacks of 'impacts' may be reduced by deflector shields fitted in the liner in front of the teat openings. One-way valves in the short milk tube will virtually prevent any contamination of the teats.