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Organic carbon concentration profiles in recent cave sediments: records of agricultural pollution or diagenesis?.
1996
Bottrell S.H.
Ozone alters carbon allocation in loblolly pine: assessment with carbon-11 labeling.
1990
Spence R.D. | Rykiel E.J. Jr. | Sharpe P.J.H.
The carbon budget of Canadian forests: A sensitivity analysis of changes in disturbance regimes, growth rates, and decomposition rates.
1994
Kurz W.A. | Apps M.J.
Changement du systeme climatique: les dernieres decouvertes scientifiques.
1994
Uptake of terbuthylazine and its medium polar metabolites into maize plants.
1995
Gayler S. | Trapp S. | Matthies M. | Schroll R. | Behrendt H.
Carbonaceous aerosol at urban and rural sites in the United States.
1986
Shah J.J. | Johnson R.L. | Heyerdahl E.K. | Huntzicker J.J.
Dissolved organic carbon in the unsaturated zone under land irrigated by wastewater effluent.
1990
Amiel A.J. | Magaritz M. | Ronen D. | Lindstrand O.
The importance of total organic carbon and trihalomethane formation potential in monitoring of groundwater and surface water quality
1999
Ivancev-Tumbas, I. | Dalmacija, B. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za hemiju)
Determination of total organic carbon content (TOC) and trihalomethane formation potential (THMFP) as well as correlation of those two parameters is recommended for monitoring of water bodies which are considered as drinking water resources. Those parameters would enable a categorization of water bodies from the protection point of view as well as from view of their usage as drinking water sources. Relationship between TOC and THMFP is dependent on the origin and the structure of organic matter in water. In this paper the correlation of TOC and THMFP is given for different kind of resources.
Afficher plus [+] Moins [-]Blood mercury concentrations in four sympatric gull species from South Western France: Insights from stable isotopes and biologging
2022
Jouanneau, William | Sebastiano, Manrico | Rozen-Rechels, David | Harris, Stephanie M. | Blévin, Pierre | Angelier, Frédéric | Brischoux, François | Gernigon, Julien | Lemesle, Jean-Christophe | Robin, Frédéric | Cherel, Yves | Bustamante, Paco | Chastel, Olivier
Mercury (Hg) is a toxic trace element widely distributed in the environment, which particularly accumulates in top predators, including seabirds. Among seabirds, large gulls (Larus sp) are generalist feeders, foraging in both terrestrial and marine habitats, making them relevant bioindicators of local coastal Hg contamination. In the present study, we reported blood Hg concentrations in adults and chicks of four different gull species breeding on the French Atlantic coast: the European herring gull (Larus argentatus), the Lesser black-backed gull (L. fuscus), the Great black-backed gull (L. marinus) and the Yellow-legged gull (L. michahellis). We also investigated the potential role of foraging ecology in shaping Hg contamination across species, using the unique combination of three dietary tracers (carbon, nitrogen and sulfur stable isotopes) and biologging (GPS tracking). A high concentration of Hg was associated with high trophic position and a marine diet in gulls, which was corroborated by birds’ space use strategy during foraging trips. Adults of all four species reached Hg concentrations above reported toxicity thresholds. Specifically, adults of Great black-backed gulls had a high trophic marine specialized diet and significantly higher Hg concentrations than the three other species. Blood Hg was 4–7 times higher in adults than in chicks, although chicks of all species received mainly marine and high trophic position prey, which is expected to be the cause of blood Hg concentrations of toxic concern. By using both stable isotopes and GPS tracking, the present study provides compelling insights on the main feeding habits driving Hg contamination in a seabird assemblage feeding in complex coastal environments.
Afficher plus [+] Moins [-]Inhalation bioaccessibility of multi-class organic pollutants associated to atmospheric PM2.5: Correlation with PM2.5 properties and health risk assessment
2022
Sánchez-Piñero, Joel | Novo-Quiza, Natalia | Pernas-Castaño, Cristina | Moreda-Piñeiro, Jorge | Muniategui-Lorenzo, Soledad | López-Mahía, Purificación
Inhalation exposure to fine particulate matter (PM₂.₅) represents a global concern due to the adverse effects in human health. In the last years, scientific community has been adopted the assessment of the PM₂.₅-bound pollutant fraction that could be released (bioaccessible fraction) in simulated lung fluids (SLFs) to achieve a better understanding of PM risk assessment and toxicological studies. Thus, bioaccessibility of 49 organic pollutants, including 18 polycyclic aromatic hydrocarbons (PAHs), 12 phthalate esters (PAEs), 11 organophosphorus flame retardants (OPFRs), 6 synthetic musk compounds (SMCs) and 2 bisphenols in PM₂.₅ samples was evaluated. The proposed method consists of a physiologically based extraction test (PBET) by using artificial lysosomal fluid (ALF) to obtain bioaccessible fractions, followed by a vortex-assisted liquid-liquid microextraction (VALLME) and a final analysis by programmed temperature vaporization-gas chromatography-tandem mass spectrometry (PTV-GC-MS/MS). The highest inhalation bioaccessibility ratio was found for bisphenol A (BPA) with an average of 83%, followed by OPFRs, PAEs and PAHs (with average bioaccessibilities of 68%, 41% and 34%, respectively). Correlations between PM₂.₅ composition (major ions, trace metals, equivalent black carbon (eBC) and UV-absorbing particulate matter (UVPM)) and bioaccessibility ratios were also assessed. Principal Component Analysis (PCA) suggested that PAHs, PAES and OPFRs bioaccessibility ratios could be positively correlated with PM₂.₅ carbonaceous content. Furthermore, both inverse and positive correlations on PAHs, PAEs and OPFRs bioaccessibilites could be accounted for some major ions and metal (oid)s associated to PM₂.₅, whereas no correlations comprising considered PM₂.₅ major ions and metal (oid)s contents and BPA bioaccessibility was observed. In addition, health risk assessment of target PM₂.₅-associated PAHs via inhalation was assessed in the study area considering both total and bioaccessible concentrations, being averaged human health risks within the safe carcinogenic and non-carcinogenic levels.
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