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See detailUnderstanding the gap between the estrogenicity of an effluent and its real impact into the wild
Nadzialek, Stéphanie; Vanparys; Van Der Heiden, Edwige ULg et al

in Science of the Total Environment (2010), 408(4), 812-821

To study the reliability between in vitro and in vivo data collected downstream 2 sewage treatment plants (STP) as well as from bleached kraft mill industry (BKME), 5 rivers (3 impacted and 2 references ... [more ▼]

To study the reliability between in vitro and in vivo data collected downstream 2 sewage treatment plants (STP) as well as from bleached kraft mill industry (BKME), 5 rivers (3 impacted and 2 references) were investigated in the Walloon region (southern of Belgium). For the in vitro part of the work, water samples were collected to measure the estrogenicity of the ‘out’ effluent compared to reference sample point by MCF-7 assay. Results indicated significant estrogenicity of effluents from STP and BKME and a weak estrogenicity in reference sites. However, estradiol equivalents (EEQ) estimated into rivers were probably too low to impact wild population. Chemical analysis of 13 compounds of interest indicated that extraction procedure used in this study gave low recoveries of estrogen-like xenobiotics, leading to probably under-estimated MCF-7 responses. Surprisingly, a full scan mode has revealed an unexpected compound in the sample of BKME which was: 7-isopropyl-1,1,4a-trimethyl-1,2,3,4a,9,10,10a-octahydrophenanthrene, a product of pulp mill manufacture. In parallel to in vitro, in vivo assessment of estrogenic impact of effluent was followed on the gudgeon (Gobio gobio). Samples were achieved during 2 different periods of the reproductive cycle, resting period (RP) and pre-spawning period (pSP). Unspecific physiological parameters to estrogenic exposure (gonadosomatic index and systematic testis cell counting) displayed no significant differences related to endocrine disruption of the reproductive tract, only differences were correlated with the reproductive state of fish (RP versus pSP). Concerning the potent biomarker of estrogen exposure, vitellogenin (vtg), only basal induction was revealed but not related to estrogenic exposure. Nevertheless, vtg over-expression was found for male fish presenting a feminization of the reproductive tract captured downstream the STP station of Wégnez in the Vesdre River. Intersexuality, another indicator of the estrogenicity impact in fish, was observed in every site. Actually, ovotestis was systematically formed by protoplasmic oocyte observed in low percentage in every group analysed (impacted and references). Moreover, in fish captured in Wégnez, oocyte diameter was significantly higher compared to the other groups. In this study, only moderate to none impact in population of gudgeon was noticed. Moreover, in this case no discrepancy between in vitro and vivo was viewed although both approaches revealed gaps in monitoring effluent incidence into the environment. We should remain careful in the interpretation when only partial approaches are used in order to characterize impact in the aquatic milieu. [less ▲]

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See detailExpression characteristics of potential biomarker genes in Tra catfish, Pangasianodon hypophthalmus, exposed to trichlorfon
Sinha, Amit Kumar; Vanparys, Caroline; De Boeck et al

in Comparative Biochemistry and Physiology. Part D, Genomics & Proteomics (2010), 5(3), 207-216

Trichlorfon (TRC) is the most common organophosphorous insecticide used in aquaculture practices in Southeast Asian countries. Indiscriminate use of TRC can either damage or alter the enzymatic and ... [more ▼]

Trichlorfon (TRC) is the most common organophosphorous insecticide used in aquaculture practices in Southeast Asian countries. Indiscriminate use of TRC can either damage or alter the enzymatic and hormonal activities in the living organisms. In this present study, therefore, toxicogenomic analyses using real time PCR was used to characterize expression levels of various genes in Pangasianodon hypophthalmus after exposure to three concentrations, the 96 h 1/100LC50 (0.01 mg/L), the 96 h 1⁄10LC50 (0.1 mg/L) and the 96 h 1⁄2LC50 (0.5 mg/L) of TRC for 6 h, 24 h, 96 h, 7 days, 14 days, 28 days and 56 days respectively. The expression kinetics of stress and other cellular toxicity representative genes such as heat shock protein70 (HSP70), growth hormone, acetylcholinesterase (AChE), trypsinogen, cytochrome P4501B (CYP1B) and cytochrome oxidase subunit 1 (COI) were investigated in liver and gills. TRC at a level of 0.1 mg/L and 0.5 mg/L induced a time and dose-dependent increase in the expression of the HSP70, COI and CYPIB while the transcript level of AChE, growth hormone and trypsinogen were significantly down-regulated. These results could permit to develop a ‘molecular biomarker system’ which can be applied as a first-tier method of identifying contaminant exposure before effects at population level occur. [less ▲]

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See detailOccurrence of perfluorooctane sulfonate and other perfluorinated alkylated substances in harbor porpoises from the Black Sea
Van de Vijver, Kristin Inneke; Holsbeek, Ludo; Das, Krishna ULg et al

in Environmental Science & Technology (2007), 41(1), 315-320

Perfluorooctane sulfonate (PFOS) and other perfluorinated alkylated substances (PFAS) were determined in liver, kidney, muscle, brain, and blubber samples of 31 harbor porpoises (Phocoena phocoena relicta ... [more ▼]

Perfluorooctane sulfonate (PFOS) and other perfluorinated alkylated substances (PFAS) were determined in liver, kidney, muscle, brain, and blubber samples of 31 harbor porpoises (Phocoena phocoena relicta) of different age and sex stranded along the Ukrainian coast of the Black Sea. In all individuals and in all tissues, PFOS was the predominant PFAS, accounting for on average 90% of the measured PFAS load. PFOS concentrations were the highest in liver (327 +/- 351 ng/g wet wt) and kidney (147 +/- 262 ng/g wet wt) tissue, and lower in blubber (18 +/- 8 ng/g wet wt), muscle (41 +/- 50 ng/g wet wt), and brain (24 +/- 23 ng/g wet wt). No significant differences could be determined between males and females, nor between juvenile and adult animals (p > 0.05). Perfluorononanoic acid, perfluorodecanoic acid, perfluoroundecanoic acid, and perfluorododecanoic acid could be detected in liver tissue of approximately 25% of the individuals. Perfluorobutane sulfonate, perfluorobutanoic acid, and perfluorooctanoic acid were not detected in any of the porpoise livers. Although we investigated a potential intraspecies segregation according to the source of prey, using stable isotopes, no statistically significant correlation between PFOS concentrations and stable isotopes could be determined. It is, however, noteworthy that the contamination by PFOS in the Black Sea harbor porpoises is comparable to levels found in porpoises from the German Baltic Sea and from coastal areas near Denmark and, therefore, might pose a threat to this population. [less ▲]

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See detailTissue distribution of perfluorinated chemicals in harbor seals (Phoca vitulina) from the Dutch Wadden Sea
Van de Vijver, Kristin Inneke; Hoff, Philippe; Das, Krishna ULg et al

in Environmental Science & Technology (2005), 39(18), 6978-6984

Perfluorinated acids (PFAs) are today widely distributed in the environment, even in remote arctic areas. Recently, perfluorooctane sulfonate (PFOS) has been identified in marine mammals all over the ... [more ▼]

Perfluorinated acids (PFAs) are today widely distributed in the environment, even in remote arctic areas. Recently, perfluorooctane sulfonate (PFOS) has been identified in marine mammals all over the world, but information on the compound-specific tissue distribution remains scarce. Furthermore, although longer perfluorinated carboxylic acids (PFCAs) are used in industry and were shown to cause severe toxic effects, still little is known on potential sources or their widespread distribution. In this study, we report for the first time on levels of longer chain PFCAs, together with some short chain PFAs, perfluorobutane sulfonate (PFBS) and perfluorobutanoate (PFBA), in liver, kidney, blubber, muscle, and spleen tissues of harbor seals (Phoca vitulina) from the Dutch Wadden Sea. PFOS was the predominant compound in all seal samples measured (ranging from 89 to 2724 ng/g wet weight); however, large variations between tissues were monitored. Although these are preliminary results, it is, to our knowledge, the first time that PFBS could be found at detectable concentrations (2.3 +/- 0.7 ng/g w wt) in environmental samples. PFBS was only detected in spleen tissue. PFCA levels were much lower than PFOS concentrations. The dominant PFCA in all tissues was PFNA (perfluorononanoic acid), and concentrations generally decreased in tissues for all other PFCA homologues with increasing chain length. No clear relationship between PFOS levels in liver and kidney was observed. Furthermore, hepatic PFDA (perfluorodecanoic acid) levels increased with increasing body length, but in kidney tissue, PFDA levels showed an inverse relationship with increasing body length. These data suggest large differences in tissue distribution and [less ▲]

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See detailBaseline study of perfluorochemicals in harbour porpoises (Phocoena phocoena) from Northern Europe
Van de Vijver, Kristin Inneke; Hoff, P. T.; Das, Krishna ULg et al

in Marine Pollution Bulletin (2004), 48(9-10), 992-997

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See detailPerfluorinated chemicals infiltrate ocean waters: Link between exposure levels and stable isotope ratios in marine mammals
Van de Vijver, Kristin Inneke; Hoff, Philippe Tony; Das, Krishna ULg et al

in Environmental Science & Technology (2003), 37(24), 5545-5550

This is the first study to report on concentrations of perfluorinated organochemicals (FOCs) in marine mammals stranded along the southern North Sea coast in relation to stable nitrogen and carbon isotope ... [more ▼]

This is the first study to report on concentrations of perfluorinated organochemicals (FOCs) in marine mammals stranded along the southern North Sea coast in relation to stable nitrogen and carbon isotope ratios (delta(15)N and delta(13)C). The presence of FOCs in top predators such as marine mammals would indicate a potential biomagnification of these compounds and their widespread occurrence. Liver and kidney tissues of nine marine mammal species have been sampled. Among all the measured FOCs compounds, PFOS (perfluorooctane sulfonate) was predominant in terms of concentration. The highest PFOS concentrations were found in the liver of harbor seal compared to white-beaked dolphin, harbor porpoise, gray seal, sperm whale, white-sided dolphin, striped dolphin, fin whale, and hooded seal. PFOS concentrations differed significantly between sexes and age classes in harbor porpoises. Stable isotope measurements (delta(13)C and delta(15)N) were used in this study to describe the behavior of contaminants in food webs. We found a significant (p < 0.05) linear relationship between PFOS concentrations in livers of harbor porpoises and both Muscle delta(13)C and delta(15)N measurements. Harbor and gray seals and white-beaked dolphin, which displayed the highest trophic position, contained the highest PFOS levels, while offshore feeders such as sperm whales,fin whales, striped dolphin, and white-sided dolphin showed lower PFOS concentrations than inshore species. [less ▲]

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See detailLevels and enantiomeric signatures of methyl sulfonyl PCB and DDE metabolites in livers of harbor porpoises (Phocoena phocoena) from the southern North Sea
Chu, Shaogang; Covaci, Adrian; Haraguchi, Koichi et al

in Environmental Science & Technology (2003), 37(20), 4573-4578

The concentration of 26 methyl sulfonyl metabolites of polychlorinated biphenyls (MeSO2-PCBs) and of p,p'-DDE (MeSO2-DDE) were determined in 19 liver samples from harbor porpoises (Phocoena phocoena ... [more ▼]

The concentration of 26 methyl sulfonyl metabolites of polychlorinated biphenyls (MeSO2-PCBs) and of p,p'-DDE (MeSO2-DDE) were determined in 19 liver samples from harbor porpoises (Phocoena phocoena) stranded between 1997 and 2000 on the Belgian and French North Sea Coasts. The total concentration of MeSO2-PCBs ranged from 39 to 4221 ng/g lipid weight (lw) and were generally higher in adults (age >2 yr, range 969-4221 ng/g lw) than in juveniles (age <2 yr, range 39-1815 ng/g lw). The concentrations of MeSO2-DDE were generally also higher in adults (2196 ng/g lw) than in juveniles (0.5-60 ng/g lw). Congeners 3- and 4-MeSO2-CB101 were the dominating metabolites in all samples. Due to their preferential retention in the liver, the MeSO2-PCB congeners could be divided into two groups. The first group was dominated by the 3-MeSO2-PCB congeners and consisted of MeSO2-CB31, -CB49, -CB52, -CB87, and -CB101, which all have a 2,5-chlorine substitution in the phenyl ring containing the methyl sulfonyl group. The second group was dominated by the 4-MeSO2-PCB congeners and consisted of MeSO2-CB64, -CB91, -CB110, and -CB132, which all have a 2,3,6-chlorine substitution. The ratios of sum of PCBs/sum of MeSO2-PCBs and p,p-DDE/MeSO2-DDE differed greatly between individual subjects and ranged from 15 to 419 and from 17 to 1088, respectively. The ratio between the precursor PCB congeners and their corresponding metabolites ranged from 0.6 (CB49) to 175 (CB174). Enantiomeric fractions (EFs) for MeSO2-PCB atropisomers, which include 3-MeSO2-CB132, 3-MeSO2-CB149, 4-MeSO2-CB149, 3-MeSO2-CB174, and 4-MeSO2-CB174, were also measured in 8 out of the 19 subjects. High enantiomeric excess (EF > 0.73 or EF < 0.23) for the measured chiral MeSO2-PCB congeners was found in all samples. This result may suggest that one atropisomer may be preferentially formed in harbor porpoises or that the atropisomers are retained in a highly selective manner. [less ▲]

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See detailDetermination of organohalogenated contaminants in liver of harbour porpoises (Phocoena phocoena) stranded on the Belgian North Sea coast
Covaci, Adrian; Van de Vijver, Kristin Inneke; De Coen, Wim et al

in Marine Pollution Bulletin (2002), 44(10),

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