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An environmental risk assessment of three organic UV-filters at Lac Bay, Bonaire, Southern Caribbean Texte intégral
2018
Schaap, Iris | Slijkerman, Diana M.E.
Although organic UV filters (OUVFs) benefit human health by preventing skin burns and cancer, several studies revealed that organic UV filters can induce developmental and reproductive toxicity to aquatic organisms. Discharge of OUVFs occurs predominantly at marine recreational hotspots, such as Lac Bay, Bonaire, and is predicted to increase significantly due to growing tourism worldwide. Unfortunately, there is no insight what the current and future discharge of OUVF at Lac Bay is. Therefore, this study aimed to 1) measure concentrations and estimate the risk of specific OUVFs to different nursery habitats at Lac Bay, and 2) compare measured and predicted concentration based risk assessment outcome. Results showed that at least one of the three nurseries at Lac Bay had a potential for adverse effects. Furthermore, predicted environmental concentrations of UV filter discharge can be applied to gain more insight in the order of extent of OUVF discharge by marine tourism.
Afficher plus [+] Moins [-]Sorption behaviors of tris-(2,3-dibromopropyl) isocyanurate and hexabromocyclododecanes on polypropylene microplastics Texte intégral
2018
Liu, Xiaowen | Zheng, Minggang | Wang, Ling | Ke, Runhui | Lou, Yinghua | Zhang, Xiaojun | Dong, Xiaofeng | Zhang, Yu
In recent years, microplastics in oceans have become a serious environmental problem and the focus of attention. In the present study, the sorption of TBC and HBCDs by microplastics in simulated seawater is examined. The effects of particle size, temperature, salinity, and concentration on the adsorption of TBC and HBCDs by microplastics are studied. Results indicate that the first-order adsorption kinetic model is more suitable than the pseudo-second-order kinetic model to describe adsorption. The equilibrium adsorption times are 15 h and 10 h for TBC and HBCDs, respectively. The adsorption capacity increases with the decrease in particle size. The adsorption capacity gradually increases at first and then decreases with the increase in salinity and temperature. The maximum adsorption capacity is at 15 °C and 14% salinity. Compared with the linear and Freundlich models, the Langmuir model is more suitable; this indicates that the main adsorption mechanism might be chemical adsorption.
Afficher plus [+] Moins [-]Effect of marine ambient in the production of pollutants from the pyrolysis and combustion of a mixture of plastic materials Texte intégral
2018
Iñiguez, M.E. | Conesa, J.A. | Soler, A.
Effect of marine ambient in the production of pollutants from the pyrolysis and combustion of a mixture of plastic materials Texte intégral
2018
Iñiguez, M.E. | Conesa, J.A. | Soler, A.
A mixture of polyethylene (PE), polyethylene-terephtalate (PET), polypropylene (PP) and Nylon was submerged in marine water during 12 moths. The chlorine content of these plastics was measured through the passing time. Thermobalance was used to look for differences in the thermal decomposition of the plastics during in that time interval. Degradation of PET, PP and Nylon produced changes in the weight loss curve, but behaviour of PE is confusing. Pyrolysis and combustion at 850 °C was finally performed to get knowledge of the possible differences in the emission of main gases, volatiles and semivolatiles including polycyclic aromatic hydrocarbons (PAHs), polychlorinated benzenes (ClBzs), polychlorinated phenols (ClPhs), polybrominated phenols (BrPhs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Results show that the emission of chlorinated species is somewhat not affected by the chlorine content of the plastics mix. The production of PCBs and PCDD/Fs was very low, under 4 pg WHO-TEQ/g.
Afficher plus [+] Moins [-]Effect of marine ambient in the production of pollutants from the pyrolysis and combustion of a mixture of plastic materials Texte intégral
2018
Iñiguez, María Esperanza | Conesa, Juan A. | Soler, Aurora | Universidad de Alicante. Departamento de Ingeniería Química | Residuos, Energía, Medio Ambiente y Nanotecnología (REMAN)
A mixture of polyethylene (PE), polyethylene-terephtalate (PET), polypropylene (PP) and Nylon was submerged in marine water during 12 moths. The chlorine content of these plastics was measured through the passing time. Thermobalance was used to look for differences in the thermal decomposition of the plastics during in that time interval. Degradation of PET, PP and Nylon produced changes in the weight loss curve, but behaviour of PE is confusing. Pyrolysis and combustion at 850 °C was finally performed to get knowledge of the possible differences in the emission of main gases, volatiles and semivolatiles including polycyclic aromatic hydrocarbons (PAHs), polychlorinated benzenes (ClBzs), polychlorinated phenols (ClPhs), polybrominated phenols (BrPhs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Results show that the emission of chlorinated species is somewhat not affected by the chlorine content of the plastics mix. The production of PCBs and PCDD/Fs was very low, under 4 pg WHO-TEQ/g. | This work was supported by the CTQ2016-76608-R project from the Ministry of Economy, Industry and Competitiveness (Spain) and the PROMETEOII/2014/007 project of the Valencian Community regional Government (Spain). The author M.E. Iñiguez also thanks the Ministry of Economy, Industry and Competitiveness (Spain) for a Ph.D. grant (contract grant number BES-2014-069473).
Afficher plus [+] Moins [-]Bioavailable dissolved organic matter and its spatio-temporal variation in a river dominated tropical brackish water Lagoon, India Texte intégral
2018
Kanuri, Vishnu Vardhan | Muduli, Pradipta R. | R.S., Robin | B., Charan Kumar | A., Lova Raju | Patra, Sivaji | Gupta, G.V.M. | Nageswara Rao, G. | A.V., Raman | B.R., Subramanian
Bioavailable dissolved organic carbon (BDOC), nitrogen (BDON) and their degradation rate constants were measured for the Chilika Lagoon, India. Long-term laboratory incubation experiments (90 days) were conducted at a constant temperature (25 °C) to quantify the bioavailable dissolved organic matter (DOM) and the possible degradation rate coefficients. The results showed that 41 ± 12% of dissolved organic carbon (DOC) and 47 ± 17% of dissolved organic nitrogen (DON) were BDOC and BDON respectively, with their stoichiometry found to be higher than the Redfield ratio. A first order exponential non-linear fitting routine was used to estimate pool sizes. The degradation rate constant (k) for the BDOC varied from 0.127–0.329 d−1 and BDON from 0.043–0.306 d−1 during the study period. Half-lives of the BDOC and BDON ranged from 2.1–5.4 and 2.2–15.9 days, respectively. Overall, the results showed that a fraction of the labile DON was transported from the lagoon to the adjacent coastal sea.
Afficher plus [+] Moins [-]Study on the bacterial and archaeal community structure and diversity of activated sludge from three wastewater treatment plants Texte intégral
2018
Qin, Hui | Ji, Bin | Zhang, Shufei | Kong, Zehua
In this study, the bacterial and archaeal communities along with their functions of activated sludge from three wastewater treatment plants were investigated by Illumina MiSeq Platform. The treatment processes were modified A/A/O, DE oxidation ditch and pre-anaerobic carrousel oxidation ditch, respectively. The taxonomic analyses showed that Proteobacteria was the predominant bacterial phylum, and Nitrosospira was the dominant nitrification genus. Candidatus Accumulibacter was abundant in DE oxidation ditch process, and the main archaea communities were methanosaeta-like species which had the capability to anaerobic ammonia oxidation. The results illustrated that anaerobic ammonium oxidation played an important role in the nitrogen metabolism and there might be other unknown phosphate-accumulating organisms (PAOs) performing phosphorus removal in activated sludge. The predicted function analyses indicated that both bacteria and archaea were involved in nitrification, denitrification, ammonification and phosphorus removal processes, and their relative abundance varied metabolic modules differed from each other.
Afficher plus [+] Moins [-]Temporal metal concentration in coastal sediment at the north region of Persian Gulf Texte intégral
2018
Maghrebi, Mohsen | Karbassi, Abdolreza | Lak, Raziyeh | Noori, Roohollah | Sadrinasab, Masoud
The purpose of this article is to study, result of metal concentration in two-sediment cores from Persian Gulf. Age of sediment is determined by C14 isotope method and bulk concentration is determined by ICP. This research output shows that, age of BandareAbbas core back to 9660 and Bushehr core to 15,600 years ago. Also,concentration in BandareAbbas and Bushehr cores respectively change as, As (1.08–11.76 Vs 5.2–13.09), Ba (15.03–129.5 Vs 73.9–120.4), Cd (0.09–0.46 Vs 0.09–0.18), Li (5.66–58.5 Vs 15.3–33.4), Mo (0.3–0.75 Vs 0.3–0.8), Mg (7928.4–15,503.9 Vs 13,102.8–17,227.8), Mn (110.6–566.4 Vs 279.3–429.1), Na (8905.47–27,993.3 Vs 9357.7–27,541.4), Ni (13.3–110.3 Vs 37.1–88.4), Pb (0.5–42.5 Vs 2.5–13.6), Sr (407.5–1773.2 Vs 440.3–1596.9), Zn (13.05–71.2Vs22.4–50.5), Fe (0.46–4.07 Vs 1.7–3.18), Ca (9.25–23.3 Vs 13.8–19.2) and Al (0.62–8.15 Vs 2.48–4.65). Moreover different pollution index investigation represent that except Ca, the rest of the metal elements do not show pollution.
Afficher plus [+] Moins [-]Heavy metal pollution and its relation to the malformation of green mussels cultured in Muara Kamal waters, Jakarta Bay, Indonesia Texte intégral
2018
Riani, Etty | Cordova, Muhammad Reza | Arifin, Zainal
Jakarta Bay has become contaminated by both organic and inorganic pollutants, including heavy metals. This study aimed to examine the effect of heavy metal pollution on green mussels cultured in Muara Kamal Waters, Jakarta Bay over seven months. In this research, the water quality was assessed, through measuring the concentrations of the heavy metals, Hg, Pb, Cd, Cr, and Sn in the water, and in the tissue of green mussels that had been cultured there for seven months. The percentage of congenital abnormalities (malformations) in the green mussels was analyzed descriptively and the relationship between the water quality, heavy metals, and green mussel malformation was studied through principal component analysis (PCA). The result showed that the heavy metals concentrations in the water and sediment exceeded the quality standard at Muara Kamal but that in other respects the water quality was quite good. The green mussels cultured there for seven months had accumulated high concentrations of heavy metals, and ±60% of them had malformations of their shells. Based on the heavy metal concentrations in their bodies, the main cause of malformations in green mussels was suspected to be Pb, Hg, and Sn. However, the result of PCA showed it was the interaction between nitrogen compounds, phosphate, turbidity, salinity, pH, as well as the heavy metals in the water that determined the green mussel abnormality.
Afficher plus [+] Moins [-]Influence of river discharge on abundance and composition of phytoplankton in the western coastal Bay of Bengal during peak discharge period Texte intégral
2018
Bharathi, M.D. | Sarma, V.V.S.S. | Ramaneswari, K. | Venkata Ramana, V.
To understand the influence of river discharge on phytoplankton composition along western coastal Bay of Bengal (BoB), surface water samples were collected during peak discharge period. River discharge from the Ganges influences northwest (NW) coastal BoB whereas peninsular rivers (Godavari and Krishna) discharge to the southwest (SW) coastal Bay. River discharge from the Ganges is an order of magnitude higher than peninsular river resulting in low saline, less suspended matter and lower nutrients concentrations in the NW and contrasting to that was observed in the SW. ~50%of the phytoplankton were composed of Thalassiosira spp., Nitzschia spp., Microcystis spp., Amphiprora spp. and Thalassionema spp. in the SW whereas Thalassiosira spp., Nitzschia spp., Chaetoceros spp., Merismopedia spp. and Peridinium spp. in the NW. Significant variability in phytoplankton composition was observed from coast to offshore. Our study revealed that river discharge and associated physico-chemical characteristics governed the phytoplankton community along western coastal BoB.
Afficher plus [+] Moins [-]Double trouble in the South Pacific subtropical gyre: Increased plastic ingestion by fish in the oceanic accumulation zone Texte intégral
2018
Markic, Ana | Niemand, Clarisse | Bridson, James H. | Mazouni-Gaertner, Nabila | Gaertner, Jean-Claude | Eriksen, Marcus | Bowen, Melissa
Fish are an important food source for South Pacific (SP) island countries, yet there is little information on contamination of commercial marine fish species by plastic. The aim of our study was to perform a broad-scale assessment of plastic ingestion by fish common in the diet of SP inhabitants. We examined 932 specimens from 34 commercial fish species across four SP locations, and some of the prey they ingested, for the presence of marine plastics. Plastic was found in 33 species, with an average ingestion rate (IR) of 24.3 ± 1.4% and plastic load of 2.4 ± 0.2 particles per fish. Rapa Nui fish exhibited the greatest IR (50.0%), significantly greater than in other three locations. Rapa Nui is located within the SP subtropical gyre, where the concentration of marine plastics is high and food is limited. Plastic was also found in prey, which confirms the trophic transfer of microplastics.
Afficher plus [+] Moins [-]Macroalgae as a tool for assessing the ecological status of coral reefs under the Water Framework Directive: A case study on the reef flats of La Réunion (Indian Ocean) Texte intégral
2018
Zubia, Mayalen | Depetris, Mathieu | Flores, Olivier | Turquet, Jean | Cuet, Pascale
The monitoring of macroalgae is required by the Water Framework Directive (WFD) to achieve good ecological status for coastal waters and specific questions arise for tropical ecosystems belonging to the outermost European regions. To assess the suitability of macroalgae as a biological quality indicator for La Réunion reef flats (France), we performed multivariate analyses linking the abundance and composition of macroalgae to water physico-chemistry. Three hydrological groups of stations were identified according to dissolved inorganic nitrogen (DIN) concentrations and DIN/PO4 ratios. Some indicator species were found at the N-enriched stations (Bryopsis pennata, Caulerpa lamourouxii, Chaetomoropha vieillardii, Derbesia sp., Blennothrix lyngbyacea, Sphacelaria tribuloides), and others at the non-impacted stations (Anabaena sp1, Blennothrix glutinosa, Codium arabicum, Neomeris vanbosseae). Another key result was the significant increase in red algal cover at the most N-enriched station. Our findings are discussed in the context of the application of the WFD in the outermost French regions.
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