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Triazole-induced toxicity in developing rare minnow (Gobiocypris rarus) embryos Full text
2014
Zhu, Bin | Liu, Lei | Gong, Yu-Xin | Ling, Fei | Wang, Gao-Xue
Using rare minnow (Gobiocypris rarus) at early-life stages as experimental models, the developmental toxicity of five widely used triazole fungicides (myclobutanil, fluconazole, flusilazole, triflumizole, and epoxiconazole) were investigated following exposure to 1–15 mg/L for 72 h. Meanwhile, morphological parameters (body length, body weight, and heart rate), enzyme activities (superoxide dismutase (SOD), glutathione S-transferase (GST), adenosine triphosphatase (ATPase), and acetyl cholinesterase (AChE)), and mRNA levels (hsp70, mstn, mt, apaf1, vezf1, and cyp1a) were also recorded following exposure to 0.2, 1.0, and 5.0 mg/L for 72 h. Results indicated that increased malformation and mortality, decreased body length, body weight, and heart rate provide a concentration-dependent pattern; values of 72 h LC₅₀(median lethal concentration) and EC₅₀(median effective concentration) ranged from 3 to 12 mg/L. Most importantly, the results of the present study suggest that even at the lowest concentration, 0.2 mg/L, five triazole fungicides also caused notable changes in enzyme activities and mRNA levels. Overall, the present study points out that those five triazole fungicides are highly toxic to the early development of G. rarus embryos. The information presented in this study will be helpful in better understanding the toxicity induced by triazole fungicides in fish embryos.
Show more [+] Less [-]Determination of phthalates and their by-products in tissues of roach (Rutilus rutilus) from the Orge river (France) Full text
2014
Valton, A. S. | Serre-Dargnat, C. | Blanchard, M. | Alliot, F. | Chevreuil, M. | Teil, Marie Jeanne
Seven phthalate by-products were investigated for the first time, in target tissues of roach from a contaminated river of the Ile-de-France district. All parent phthalates were bioaccumulated in liver and muscle and liver contents were correlated with river concentrations (p < 0.01). All metabolites were found in liver, plasma and bile. The mono-iso-butyl phthalate (MiBP; 1.6 μg g⁻¹dw of liver), followed by mono-n-butyl phthalate (MnBP; 1.5 μg g⁻¹dw of liver) were the most abundant ones. Among the three metabolites of di-ethylhexyl phthalate (DEHP), mono (2-ethylhexyl) phthalate (MEHP) predominated in bile (15.5 ng ml⁻¹) and liver (0.237 μg g⁻¹dw), whereas in plasma, it was mono (2-ethyl-5-hydroxyhexyl) phthalate – MEHHP (214 ng ml⁻¹). In liver, MEHP/DEHP ratios ranged from 0.04 to 0.2. Among the oxidized metabolites, only mono (2-ethyl-5-oxohexyl) phthalate (MEOHP) was correlated (p < 0.05) with parent DEHP and appeared to be a more reliable marker of DEHP impact than the monoester.
Show more [+] Less [-]The link between descriptors 8 and 9 of the Marine Strategy Framework Directive: lessons learnt in Spain Full text
2014
Gago, J. | Viñas, L. | Besada, V. | Bellas, J.
The link between descriptors 8 and 9 of the Marine Strategy Framework Directive: lessons learnt in Spain Full text
2014
Gago, J. | Viñas, L. | Besada, V. | Bellas, J.
The aim of this note is to discuss the relevance of the interaction/integration of monitoring of contaminants for the protection of the marine environment and for human health safety (descriptors 8 and 9, respectively) within the Marine Strategy Framework Directive (MSFD). The identification of possible relations between contaminant levels in sediments and tissues of fish and other seafood, as well as the association of those levels to pollution sources, are major challenges for marine researchers. The Spanish initial assessment in the North-East Atlantic marine region was used as an example to show some gaps and loopholes when dealing with the relationship between descriptors 8 and 9. The main problem to deal with is that monitoring programmes intended for the assessment of marine environmental quality and for human health safety usually apply different approaches and methodologies, and even different tissues are analysed in some species (mainly fish). It is therefore recommended to make a profound revision of current sampling strategies, procedures and methodologies, including the selection of target species and tissues and to improve the traceability of samples of fish and other seafood for human consumption. On the other hand, despite the scope of descriptor 9 which is limited to commercially relevant species, this fact should not be an obstacle in the application of the ‘ecosystem approach’ within the MSFD. In order to appropriately solve these shortcomings, an information exchange system between authorities dealing with descriptors 8 and 9 should be strongly encouraged for the next steps of the MSFD’s implementation.
Show more [+] Less [-]The link between descriptors 8 and 9 of the Marine Strategy Framework Directive: lessons learnt in Spain Full text
2014
Gago, Jesús | Viñas, Lucía | Besada, Victoria | Bellas, Juan
The aim of this note is to discuss the relevance of the interaction/integration of monitoring of contaminants for the protection of the marine environment and for human health safety (descriptors 8 and 9, respectively) within the Marine Strategy Framework Directive (MSFD). The identification of possible relations between contaminant levels in sediments and tissues of fish and other seafood, as well as the association of those levels to pollution sources, are major challenges for marine researchers. The Spanish initial assessment in the North-East Atlantic marine region was used as an example to show some gaps and loopholes when dealing with the relationship between descriptors 8 and 9. The main problem to deal with is that monitoring programmes intended for the assessment of marine environmental quality and for human health safety usually apply different approaches and methodologies, and even different tissues are analysed in some species (mainly fish). It is therefore recommended to make a profound revision of current sampling strategies, procedures and methodologies, including the selection of target species and tissues and to improve the traceability of samples of fish and other seafood for human consumption. On the other hand, despite the scope of descriptor 9 which is limited to commercially relevant species, this fact should not be an obstacle in the application of the ‘ecosystem approach’ within the MSFD. In order to appropriately solve these shortcomings, an information exchange system between authorities dealing with descriptors 8 and 9 should be strongly encouraged for the next steps of the MSFD’s implementation | This work has been supported by the Instituto Español de Oceanografía (IEO). We are very grateful to the Spanish Ministry of Environment and to all the people involved in the MSFD process in Spain, especially to those dealing with descriptors 8 and 9. We are very grateful to the three reviewers that made a number of good suggestions to improve this work. | Peer reviewed
Show more [+] Less [-]Mercury contamination in alligators (Melanosuchus niger) from Mamirauá Reservoir (Brazilian Amazon) and human health risk assessment Full text
2014
Correia, Jozélia | Cesar, Ricardo | Marsico, Eliane | Diniz, George Tadeu Nunes | Camargo, Mauricio (Camargo-Zorro) | Castilhos, Zuleica
Mercury (Hg) concentrations in muscles of wild alligators (Melanosuchus niger) from the Mamirauá Reservoir (a reference area in the Brazilian Amazon) and the human health risks associated with its consumption were assessed. The mean Hg concentration in alligator muscles was 0.407 ± 0.114 μg/g (N = 61). Close to 5 % of the muscle samples showed Hg levels above the World Health Organization guideline for fish consumption (0.5 μg/g). A positive and significant relationship was observed between Hg concentrations in muscle and the age of the specimens. The dose-response approach suggests that close to 27.4 years is required for half of the exposed specimens to attain 0.5 μg/g. The hazard quotient (HQ) is a risk indicator which defines the ratio of exposure level and a toxicological reference dose. HQ resulted above the unity for all the specimens when the ingestion rate for riverine communities (200 g of muscle per day) is considered, indicating the existence of hazard. When the ingestion rate for market consumers (28.57 g/day) is considered, the risks are much lower (mean HQ = 0.55), suggesting that such group is not at risk. The establishment of local and regional ingestion rates for riverine populations and market consumers is extremely recommended.
Show more [+] Less [-]Brown rust disease control in winter wheat: I. Exploring an approach for disease progression based on night weather conditions Full text
2014
El Jarroudi, Moussa | Kouadio, Louis | Delfosse, Philippe | Tychon, Bernard
An empirical approach for simulating the infection and progress of leaf rust (caused by Puccinia triticina) during stem elongation on winter wheat was analysed for the 2000 to 2006 growing seasons. The approach was elaborated based on night weather conditions (i.e., air temperature, relative humidity and rainfall) and leaf rust occurrences. Data from three consecutive cropping seasons (2000–2002) at four representative sites of the Grand-Duchy of Luxembourg were used in the set-up phase. The capability to correctly simulate the occurrence expression of P. triticina infections on the upper leaf layers was then assessed over the 2003–2006 period. Our study revealed that the development of leaf rust required a period of at least 12 consecutive hours with air temperatures ranging between 8 and 16 °C, a relative humidity greater than 60 % (optimal values being 12–16 °C and up to 80 % for air temperatures and relative humidity, respectively) and rainfall less than 1 mm. Moreover, leaf rust occurrences and infections were satisfactorily simulated. The false alarm ratio was ranged from 0.06 to 0.20 in all the study sites. The probability of detection and critical success index for WLR infection were also close to 1 (perfect score).
Show more [+] Less [-]Leaching of heavy metals and alkylphenolic compounds from fresh and dried sewage sludge Full text
2014
Milinović, Jelena | Vidal, Miquel | Lacorte, Silvia | Rigol, Anna
Reusing sewage sludge as a soil fertiliser has become a common alternative to disposal. Although this practice has a few benefits, it may contribute to the medium- and long-term contamination of the trophic chain because sewage sludge may contain heavy metals and organic contaminants. As the leaching of contaminants may depend on the sludge pre-treatment, the leaching of heavy metals (Cu, Ni, Pb, Zn and Cr) and alkylphenolic compounds (APCs) (octylphenol (OP), nonylphenol (NP), nonylphenol-mono-ethoxylate (NP₁EO)) was investigated in five fresh and 40 °C dried sewage sludge samples from north-eastern Spain. FT-IR analyses and full-scan GC-MS chromatograms showed that sludge drying changed the nature of organic compounds leading to changes in their solubility. Moreover, sludge drying led to a higher relative contribution of dissolved organic carbon than the particulate organic carbon in the leachates. Leaching of Pb, Zn and Cr was below 5 % in both fresh and dried sludge samples, whereas Cu and Ni leached at rates up to 12 and 43 %, respectively, in some of the dried sludge samples. The leaching yields of OP, NP and NP₁EO ranged from 1.3 to 35 % for fresh samples, but they decreased from 0.8 to 3.4 % in dried samples. The decrease in the leachability of APCs observed in dried sludge samples might be attributed to the fact that these compounds are associated with particulate organic matter, with significantly lower concentration or even absent in dried sludge than in fresh sludge samples. Therefore, it is recommended to dry the sludge before its disposal.
Show more [+] Less [-]Treatment of dilute methylene blue-containing wastewater by coupling sawdust adsorption and electrochemical regeneration Full text
2014
Bouaziz, I. | Chiron, C. | Abdelhedi, R. | Savall, A. | Groenen Serrano, K.
In the present work, the coupling of adsorption and electrochemical oxidation on a boron-doped diamond (BDD) electrode to treat solutions containing dyes is studied. This coupling may be convenient for the treatment of diluted pollutant that is limited by the low rate of electrooxidation due to mass-transfer limitation. A pre-concentration step by adsorption could minimize the design of the electrochemical reactor. The adsorbent chosen was mixed with softwood sawdust, and methylene blue was chosen as the model dye molecule. Isotherms of adsorption and kinetics were investigated as well as the effects of current density and regeneration time. The BDD electrochemical oxidation of methylene blue adsorbed onto sawdust led simultaneously to its degradation and sawdust regeneration for the next adsorption. It was observed that multiple adsorption and electrochemical regeneration cycles led to an enhancement of adsorption capacity of the sawdust. This study demonstrated that adsorption–electrochemical degradation coupling offers a promising approach for the efficient elimination of organic dyes from wastewater.
Show more [+] Less [-]Bages-Sigean and Canet-St Nazaire lagoons (France): physico-chemical characteristics and contaminant concentrations (Cu, Cd, PCBs and PBDEs) as environmental quality of water and sediment Full text
2014
Vouvé, Florence | Buscail, Roselyne | Aubert, Dominique | Labadie, Pierre | Chevreuil, Marc | Canal, Christophe | Desmousseaux, Marion | Alliot, Fabrice | Amilhat, Elsa | Faliex, Elisabeth | Paris-Palacios, Séverine | Biagianti-Risbourg, Sylvie
Environmental characteristics in water and sediments of two contrasted coastal Mediterranean lagoons, Bages-Sigean and Canet-St Nazaire, were measured over a three season survey. The urban pollution (treatment plant discharges) is very important in Canet-St Nazaire lagoon reflecting untreated sewages, while in Bages-Sigean, the northern part appears more impacted due to larger anthropogenic inputs. Dissolved Cd concentrations are on the whole similar in both lagoons, whereas Cu concentrations are by far higher in lagoon Canet-St Nazaire. Cu concentrations appear to be highly dependent on dissolved organic carbon whereas salinity seems to control Cd variations. Concerning the sediments, the confined northern part of lagoon Bages-Sigean shows organic carbon and total nitrogen enrichment whereas lipid concentrations are much higher in the Canet-St Nazaire lagoon. Cu complexation seems to be strongly related to organic matter as evidenced by the two significant positive relationships, on one hand between Cu and organic carbon, and on the other hand, between Cu and lipids. On the contrary, Cd concentrations appear to be mainly controlled by carbonates. PCBs and PBDEs were detected only in sediments and show relatively low concentrations compared to similar lagoon environments. Regarding the sediment quality guidelines, Cd, Cu and PCBs in both lagoons did not exceed any Probable Effect Concentration (PEC).
Show more [+] Less [-]Development of freshwater sediment management standards for organic matters, nutrients, and metals in Korea Full text
2014
Huh, In Ae | Kim, Yong Seok | Yu, Soon Ju | Wong, Stella | Shin, Won Sik | Park, Hye Ok | Kim, Ho Jeong | Kim, Hyun Woo
Korean water quality managers are required to promptly develop national assessment standards for freshwater sediment quality due to the Four Major River Restoration Project in Korea in 2009. We conducted this study to develop sediment management standards (SMSs), determining obviously and severely polluted sediment, which could have adverse impacts on water quality and aquatic ecosystem. The SMSs values were derived from the 95th percentile of concentration distribution for organic matter and nutrients in sediment quality database. For the SMSs of metals, foreign sediment quality guidelines (SQGs) were adopted. As a result, 13 % for loss on ignition (LOI), 1,600 mg/kg for total phosphorus (TP), and 5,600 mg/kg for total nitrogen (TN) were set as the SMSs for freshwater sediment in Korea. These values were higher than the range of heavily polluted sediment from USEPA Region 5 guideline derived by the similar approaches for the Great Lakes harbor sediments, and similar or lower than the severe effect level (SEL) from provincial sediment quality guideline (PSQG) of Ontario, Canada by screening level concentration (SLC) approach. However, SMSs in the present study are appropriate considering the concentration ranges and the Korean SMSs’ definition for freshwater sediments in Korea. The Puget Sound marine sediment cleanup screening level (CSL) in Washington State, USA were adopted as the Korean SMSs for As (93 mg/kg), Cd (6.7 mg/kg), Cr (270 mg/kg), Cu (390 mg/kg), Pb (530 mg/kg), and Zn (960 mg/kg) in freshwater sediments. Hg concentration (0.59 mg/kg) of CSL was too low to determine the polluted freshwater sediments in Korea, and the SEL of Ontario, Canada for mercury concentration (2 mg/kg) was selected as the SMS for Hg. These values were found reasonable through the assessment of applicability with the datasets from locations directly affected by obvious point sources. These results indicate that SMSs for organic matter, nutrient, and metals derived within the present study can successfully determine obviously and severely polluted sediment in Korea. However, the SMSs have limits to specifically determine the effects of polluted sediment on water quality and aquatic ecosystem in Korea. Thus, we will revise and specify SMSs considering those effects and further sediment quality assessment framework in the near future.
Show more [+] Less [-]Effect of Fenton treatment on the aquatic toxicity of bisphenol A in different water matrices Full text
2014
Arslan-Alaton, Idil | Aytac, Ece | Kusk, Kresten Ole
Battery tests serve as integral tools to decide whether a treatment process is ecotoxicologically safe or not. In the present study, a battery of toxicity tests was employed to elucidate the toxicity of the potential endocrine-disrupting pollutant bisphenol A (BPA) and its advanced oxidation products. For this purpose, BPA was subjected to Fenton treatment in the growth medium of the test organisms employed as well as in real lake water. Treatment results indicated that BPA removals were fast and complete within less than a minute, whereas total organic carbon (TOC) removals were rather incomplete, speaking for the accumulation of refractory degradation products. The presence of chloride and/or natural organic matter influenced H₂O₂ consumption rates and the treatment performance of the Fenton’s reagent as well. The sensitivity of the selected test organisms for BPA and its Fenton treatment products in different water matrices was found in the following decreasing order: the freshwater microalgae (Pseudokirchneriella subcapitata) > the freshwater cladoceran (Daphnia magna) > marine photobacteria (Vibrio fischeri).
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