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Seasonal variation and the distribution of endocrine-disrupting chemicals in various matrices affected by algae in the eutrophic water environment of the pearl river delta, China
2020
Yang, Juan | Chan, King Ming | Gong, Jian
The seasonal variation and distribution among different matrices of endocrine-disrupting chemicals (EDCs) were investigated in the eutrophic water ecosystem of the Pearl River Delta, Guangdong, China. The chlorophyll a (Chl a) levels were generally higher in summer than in spring; however, the concentrations of 4-tert-octylphenol (OP), 4-nonylphenol (NP), and bisphenol A (BPA) in surface water were generally higher in spring (oligotrophic) than in summer (eutrophic). The levels of EDCs in SPM were lower in spring than in summer, a pattern seen in the seasonal variation of Chl a and particulate organic carbon (POC). The seasonal variations of EDCs in water bodies with different levels of eutrophication were analyzed in several dimensions including sediment, POC, algae and fish bile. The log Kₒc for SPM/water was higher in summer than in spring. The log Kₒc values for NP, OP, and BPA exhibited the following trends between matrices: colloid/water > sediment/water > SPM/water > algae/water, colloid/water > sediment/water > algae/water > SPM/water, and colloid/water > algae/water > sediment/water > SPM/water. The EDCs levels were different in fish tissues with the order bile > liver > muscle, with the concentrations being an order of magnitude higher in bile than in liver and an order of magnitude higher in liver than in muscle. The sequence of the bioconcentration factor (log BCF) for bile/water and liver/water was NP < OP < BPA in eutrophic conditions, but NP > OP > BPA in oligotrophic conditions. The order in eutrophic conditions was the same as the log BCF and log Kₒc for algae/water, indicating that the accumulation of EDCs in water bodies could be affected by algae, which could be one of the reasons of the seasonal variation of EDCs in water.
Show more [+] Less [-]Similarities and differences of 137Cs distributions in the marine environments of the Baltic and Black seas and off the Fukushima Dai-ichi nuclear power plant in model assessments
2018
Maderich, V. | Bezhenar, R. | Tateda, Y. | Aoyama, M. | Tsumune, D.
The compartment model POSEIDON-R with an embedded food web model was used to assess 137Cs distributions in the Baltic and Black seas and off the Pacific coast of Japan during 1945–2020 due to the weapon testing and accidents at the Chernobyl and Fukushima Dai-ichi nuclear power plants. The results of simulations conducted with generic parameters agreed well with measurements of 137Cs concentrations in the water, bottom sediments, and in fish. In the Black and Baltic seas, salinity variations affected the transfer of 137Cs through the food web. The contamination of pelagic fish followed the water contamination with some delay, whereas demersal fish depuration was found to be related to decreasing 137Cs concentrations in the upper sediment layer. On the Pacific shelf off Japan, intensive currents and eddies caused the simulated depuration rates in fish to be one-two orders of magnitude larger than those in the semi-enclosed Black and Baltic seas.
Show more [+] Less [-]Planned release of contaminated water from the Fukushima storage tanks into the ocean: Simulation scenarios of radiological impact for aquatic biota and human from seafood consumption
2021
Bezhenar, R. | Takata, H. | With, G. de | Maderich, V.
The radiological impact for human and aquatic biota as a result of a planned release of contaminated water stored in tanks near the Fukushima Dai-ichi Nuclear Power Plant to the Pacific Ocean is assessed. The total activity for 10 dominant radionuclides (³H, ¹⁴C, ⁶⁰Co, ⁹⁰Sr, ⁹⁹Tc, ¹⁰⁶Ru, ¹²⁵Sb, ¹²⁹I, ¹³⁴Cs, ¹³⁷Cs) in tanks is estimated. The compartment model POSEIDON-R is applied to compute the concentration of activity for each radionuclide in water, bottom sediments, and biota, and corresponding doses to marine organisms and humans from seafood consumption. Predicted concentrations of activity in marine products in future will not exceed food safety limits in Japan. The computed maximum committed effective dose to humans is less than 1 μSv per year with the highest contribution from ¹²⁹I and ¹⁴C. Maximum absorbed doses to non-human biota are in the order of 0.05 to 20 μGy per year, meaning that no deleterious effects are expected.
Show more [+] Less [-]Nitrification-denitrification processes and technologies in new contexts
1998
Verstraete, W. | Philips, S. (Laboratory of Microbial Ecology, University of Gent, Coupure Links 653, B-9000 Gent (Belgium))
Fate of airborne polychlorinated dibenzo-p-dioxins and dibenzofurans in an agricultural ecosystem
1998
Welsch-Pausch, K. | McLachlan, M.S. (Ecological Chemistry and Geochemistry, University of Bayreuth, 95440 Bayreuth (Germany))
[Effect of pollutants on Mediterranean littoral ecosystems]
1987
Vincente, N. (Faculte des Sciences et Techniques, Marseille (France). Lab. de Biologie Marine)