Search results for "Persistent organic pollutant"
showing 10 items of 40 documents
Can phthalates move into the eggs of the loggerhead sea turtle Caretta caretta? The case of the nests on the Linosa Island in the Mediterranean Sea
2021
During the monitoring of Caretta caretta nests on the island of Linosa, 30 unhatched eggs from four nests were collected to study the presence of phthalates in their three components (shell, yolk, and albumen). Four phthalates, namely diethyl (DEP), dibutyl (DBP), di-(2-ethylhexyl) (DEHP), and dioctyl (DOTP) phthalic acid esters (PAE), which are widely used as additives in plastics, were detected in all egg components. The most frequently found phthalate was DBP, followed by DEHP in eggshell and yolk. Dimethyl- (DMP) and butylbenzyl-phthalate (BBP) were below the limits of detection for all samples. The high total phthalate recorded in the yolk suggests that contamination could arise by vit…
Concentrations and determinants of organochlorine levels among pregnant women in Eastern Spain
2010
Persistent organic pollutants (POPs) comprise a large variety of toxic substances with ample distribution. While exposure to these toxins occurs mainly through diet, maternal POP levels may be influenced by certain sociodemographic, environmental, or lifestyle factors. This is important given that these substances may have adverse effects on fetal development. The aim of this study is to examine the sociodemographic, environmental, lifestyle, and dietary determinants of the levels of hexachlorobenzene (HCB), b-hexachlorocyclohexane (b-HCH), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (4,4′-DDT), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (4,4′-DDE), and polychlorinated biphenyls (PCB co…
Isolation and identification of intermediates from biodegradation of low chlorinated biphenyls (Delor-103).
2004
Abstract Microorganism Pseudomonas species P2 metabolizes polychlorinated biphenyls (PCBs) and biphenyl, producing the whole spectrum of intermediates, among them coloured intermediates, which are suitable for the monitoring of PCBs degradation by optical sensors. Knowledge of chemical structures and conditions of development of colour metabolites is necessary for application of optical analytical methods. The main goal of this work was the isolation and identification of intermediates from the biodegradation of the mixture of low chlorinated biphenyls (Delor-103), which is based on the solid phase extraction (SPE) of the whole mixture using LiChrolut EN cartridges, then silylation of the e…
HCHs and DDTs in sediment-dwelling animals from the Yangtze Estuary, China
2005
HCHs and DDTs in sediment-dwelling animals including mollusks and crabs from the Yangtze Estuary were deter- mined by GC-ECD. Levels of t-HCH were in the range of 1.2-5.5 ng g � 1 and averaged 3.5 ng g � 1 in mollusks, while t-DDT concentrations ranged from 26.0 to 68.8 ng g � 1 , with a mean of 34.5 ng g � 1 . In crabs t-HCH concentrations var- ied from 2.0 to 25.7 ng g � 1 and averaged 13.8 ng g � 1 , whereas the concentrations of t-DDT were in the range of 1.5- 24.8 ng g � 1 with a mean value of 5.9 ng g � 1 . The HCHs and DDTs levels depend on geographical position and sources, showing the high levels at fresh water area in the estuary, such as XP, CM and LHK sites, and lower at brackis…
Analyses of known and new types of polyhalogenated aromatic substances in oven ash from recycled aluminium production
2003
Abstract Persistent aromatic bromine, chlorine and mixed chlorine-bromine compounds were analysed from recycled aluminium smelter (ALS) ashes to explore the impact of brominated flame retardants (BFR) on their formation. Polybrominated diphenyl ethers (PBDE) were the most abundant original BFRs found. Induction furnace ash contained tetra- to octa-BDEs about 2000 ng g −1 in similar congener ratios as the original scrap, but contents of nona- and deca-BDEs were only 25 and 5 ng g −1 indicating their significant degradation in ALS process. In the most non-polar fraction, PCB levels and profiles were similar as earlier ALS ash samples in 1990s. The highest PCB level measured was that of deca-C…
Organochlorinated pesticides in sediments from the Lake Albufera of Valencia (Spain).
2005
Bottom sediment samples from 121 sites of the Lake Albufera of Valencia were analyzed. Dieldrin, endrin, heptachlor and op'-DDT were not detected (0.01 ng g(-1)) in 88-93% of the sites. Aldrin and HCB concentration ranges were between0.01 and 0.1 ng g(-1) in 86% and 94% of the sites, respectively. Heptachlor-epoxide and lindane 95% confidence intervals were 0.2-0.5 and 0.06-0.12, respectively. The greatest average concentration corresponds to pp'-DDE, pp'-DDD and pp'-DDT. The sum of six isomers and derivatives of the DDT average concentration reaches 2.1 ng g(-1), as opposed to 2.7 ng g(-1) for the sum of 13 pesticides considered. In the site with a major contamination, 27.0 ng g(-1) of pp'…
Phytoplankton communities of polar regions–Diversity depending on environmental conditions and chemical anthropopressure
2015
The polar regions (Arctic and Antarctic) constitute up to 14% of the biosphere and offer some of the coldest and most arid Earth's environments. Nevertheless several oxygenic phototrophs including some higher plants, mosses, lichens, various algal groups and cyanobacteria, survive that harsh climate and create the base of the trophic relationships in fragile ecosystems of polar environments. Ecosystems in polar regions are characterized by low primary productivity and slow growth rates, therefore they are more vulnerable to disturbance, than those in temperate regions. From this reason, chemical contaminants influencing the growth of photoautotrophic producers might induce serious disorders…
Polychlorinated organic compounds in the Arctic cod liver: trends and profiles
2000
Polychlorinated organic compounds (POCs) have been measured in Arctic cod liver from Vestertana Fjord for a period of 1987-1998. Significant decrease was observed for DDD (p = 0.043), alpha-HCH (p = 0.001), and gamma-HCH (lindane; p = 0.001). Contents of DDE, 2,3,7,8-tetrachlorodibenzofuran, PCBs, chlordanes, chloronaphthalenes, hexachlorobenzene and polychlorodiphenyl ethers had no significant trend. Contents of three hexa- and two heptachlorodibenzofurans and octachlorodibenzofuran increased slightly from 1987 to 1994, but then at very high rate from 1994 to 1998. Trends of HCHs, profiles of PCBs and levels of chlordanes are in accordance with atmospheric long range transport. The hexa-, …
Levels, fingerprint and daily intake of polycyclic aromatic hydrocarbons (PAHs) in bread baked using wood as fuel
2009
Concentrations, fingerprint and daily intake of 16 PAHs in 15 bread samples baked using wood as fuel are examined in this work. Analysis was performed by GC/MS after saponification of the samples and clean up of the extract. The total concentration of the 16 analytes varies from 6 to 230 microg/kg on dry weight (d.w.). The better extraction procedure was estimated by analyzing test-samples and using different extraction methods. Additionally, for every analyzed sample, the extraction yield has been determined by the use of surrogate standards. Extraction yields were never less than 77% and in most cases almost 100%. The profiles of PAHs (percentage) are similar for all the analyzed samples …
Degradation half-life times of PCDDs, PCDFs and PCBs for environmental fate modeling.
2000
Literature search of the knowledge on the degradation of persistent organic pollutants (POPs) in environmental compartments air, water, soil and sediment was done in purpose to find properties of POPs of interest for modeling. One degradation process, hydrolysis (chemical degradation), was omitted as negligibly slow for POPs studied. The other two, photolysis and biodegradation processes, were considered separately in purpose to develop estimation procedures. The estimates can be given as pseudo first-order rate constants kP for photolysis and kB for biodegradation. For each compartment, an overall degradation rate is k(tot) = kP + kB and lifetime t(1/2) = ln 2/k(tot). The latter values, li…