Effects of the fuel oil spilled by the Prestige tanker on reproduction parameters of wild mussel populations

The aim of this work was to assess possible effects of the Prestige oil spill on reproduction parameters of mussels along the Galician and Bay of Biscay coast. Studied endpoints included sex ratio, gonad histology and vitellogenin-like proteins using the alkali-labile phosphate (ALP) method. A high prevalence of haemocytic infiltration of follicles and severe oocyte atresia was found in most localities in April 2003. Spawning gonads were observed in most impacted populations in the same sampling. In April 2004 mature small sized follicles were observed. No histopathological changes were observed in April 2005 and 2006, except a high prevalence of necrotic gametes in 6 out of 22 localities in April 2006. Female ALP levels showed high interindividual variability in April 2004, which was reduced in April 2005 and 2006. No xenoestrogenic effects were observed in male mussels. Overall, gamete alterations were detected during 2003-2004 and a recovery trend was observed afterwards.     

Effects of silver and cerium dioxide micro- and nano-sized particles on Daphnia magna

Acute (96 h) and chronic (21 d) exposures of Daphnia magna neonates were carried out with nano- and micro-sized Ag and CeO(2) particles to assess the influence of both material and size of particles on mortality and moulting. Mortality rates for silver in the acute exposures were: AgNP, 56.7 ± 23.3% at 0.1 mg L(-1) and 100 ± 20% at 1 mg L(-1), and micro-Ag, 13.3 ± 6.7% at 0.1 mg L(-1) and 80 ± 20% at 1 mg L(-1). CeO(2) was not acutely toxic at concentrations up to 10 mg L(-1). Mortality for Ag over 21d at concentrations of up to 0.05 mg L(-1) was low, while mortality of 30% was observed for 0.001 mg L(-1) of nano-Ag. CeO(2), with the exception of the 10 mg L(-1) of nano-CeO(2) (100% mortality by day 7), was non-toxic. Inhibition of moulting and growth in the acute study occurred at toxic concentrations (Ag particles), and at 10 mg L(-1) of nano-CeO(2). The chronic study revealed reduced moulting at 0.001 mg L(-1) of nano-Ag and 0.01 and 0.05 mg L(-1) of both sizes of Ag, but there was no impact on D. magna size, and no effects of CeO(2). The toxicity of nano-CeO(2) may be attributed to reduced feeding and physical interference with the daphnids' carapace, resulting in reduced swimming ability. Our results suggest that Ag NPs in particular have the potential to be harmful to aquatic invertebrates after release into the environment, whereas CeO(2) particles appear to cause little adverse effects, and only at environmentally irrelevant concentrations.     

Aggregates in England—Economic contribution and environmental cost of indigenous supply

Aggregates represent one of the largest material flows in the UK economy; however, the importance of these minerals in underpinning economic activity is frequently not recognised. Features such as the spatial imbalance between resources and demand centres, exacerbated by changes in demographics and public perception, are placing increased pressure on the planning system to maintain supply. This paper sets out the direct and indirect economic contributions made by the indigenous aggregates industry to the English economy through Gross Value Added and employment sustained. It describes the key role of aggregates in construction activities, assesses the links between infrastructure development and economic growth. In 2005, aggregates extraction directly contributed £810 million of Gross Value Added to the English economy. Primary aggregates are, however, extracted at a cost to the environment and this cost, based on amenity value reduction, is estimated by updating previously published contingent valuation data. Estimates for the costs associated with carbon dioxide emissions are derived from values published by the European Union and, separately, by the UK Government. These two elements combined result in an environmental cost of indigenous extraction of £445 million in 2005. Additionally, an examination of the potential for a significant increase in the level of aggregate imports into England is made and the consequences assessed. This includes an evaluation of shipping costs and port capacity, and concludes that there are significant barriers to any substantial increase in the level of aggregate imports into England. As a consequence, indigenous supply is likely to predominate into the foreseeable future.     

Effects of environmentally relevant levels of polyethylene microplastic on Mytilus galloprovincialis (Mollusca: Bivalvia): filtration rate and oxidative stress

Environmental Science and Pollution Research - The objective of the present study was to evaluate the potential toxic effects of polyethylene microplastics (PE-MPs) (40–48 μm) on the...     

Protected area characteristics that help waterbirds respond to climate warming

Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds.     

Assessment of aerobic biodegradation of lower-chlorinated benzenes in contaminated groundwater using field-derived microcosms and compound-specific carbon isotope fractionation

Biodegradation of lower chlorinated benzenes (tri-, di- and monochlorobenzene) was assessed at a coastal aquifer contaminated with multiple chlorinated aromatic hydrocarbons. Field-derived microcosms, established with groundwater from the source zone and amended with a mixture of lower chlorinated benzenes, evidenced biodegradation of monochlorobenzene (MCB) and 1,4-dichlorobenzene (1,4-DCB) in aerobic microcosms, whereas the addition of lactate in anaerobic microcosms did not enhance anaerobic reductive dechlorination. Aerobic microcosms established with groundwater from the plume consumed several doses of MCB and concomitantly degraded the three isomers of dichlorobenzene with no observable inhibitory effect. In the light of these results, we assessed the applicability of compound stable isotope analysis to monitor a potential aerobic remediation treatment of MCB and 1,4-DCB in this site. The carbon isotopic fractionation factors (ε) obtained from field-derived microcosms were -0.7‰ ± 0.1 ‰ and -1.0‰ ± 0.2 ‰ for MCB and 1,4-DCB, respectively. For 1,4-DCB, the carbon isotope fractionation during aerobic biodegradation was reported for the first time. The weak carbon isotope fractionation values for the aerobic pathway would only allow tracing of in situ degradation in aquifer parts with high extent of biodegradation. However, based on the carbon isotope effects measured in this and previous studies, relatively high carbon isotope shifts (i.e., ∆δ¹³C > 4.0 ‰) of MCB or 1,4-DCB in contaminated groundwater would suggest that their biodegradation is controlled by anaerobic reductive dechlorination.     

Evaluation of the aerobic biodegradation of trichloroethylene via response surface methodology

Response surface methodology (RSM) was used to evaluate the effect of additives for enhancing the aerobic biodegradation of trichloroethylene (TCE). The parameters investigated include the initial TCE concentration, addition of extra bacteria, use of toluene as an inducer and hydrogen peroxide as terminal electron acceptor (TEA). Without additive, degradation efficiencies of >or=80% were obtained for TCE concentrations<700 mg/L. According to the second-order polynomial RSM and biodegradation results, the use of toluene to induce enzyme production inhibited degradation at TCE concentrations<300 mg/L. The addition of hydrogen peroxide did improve the overall degradation efficiency but decreased the degradation rate. The RSM model for toluene, extra bacteria and TEA predicted that the best approach to optimize degradation of high TCE concentrations is to ensure adequate population in conjunction with supplemental TEA.