Biotreatment and bacterial succession in an upflow immobilized cell bioreactor fed with fludioxonil wastewater

Environmental Science and Pollution Research - The large quantities and the persistent nature of fungicide wastewaters have increased the efforts towards a sustainable technological solution. In...     

Global genomic methylation levels in the liver and gonads of the three-spine stickleback (Gasterosteus aculeatus) after exposure to hexabromocyclododecane and 17-beta oestradiol

Alteration of DNA methylation is a major epigenetic mechanism associated with the effects of nongenotoxic carcinogens. We evaluated the effects of two environmental pollutants, hexabromocyclododecane (HBCD), 17-beta oestradiol (E(2)) as well as 5-aza 2' deoxycytidine (5AdC) on global DNA methylation levels (5-methyl 2' deoxycytidine) in the liver and gonads of the three-spine stickleback (Gasterosteus aculeatus). HBCD at 30 and 300 ng/L of water did not produce statistically significant differences in global genomic methylation in liver of female stickleback. On the other hand, the methylation inhibitor, 5-aza-2'-deoxycytidine, significantly lowered hepatic global methylation levels in these fish by 14% (P<0.05). The naturally occurring oestrogen, 17-beta oestradiol (E(2)) at 100 ng/L also decreased global DNA methylation levels in female liver but this effect was not statistically significant. In contrast, both E(2) and 5AdC caused statistically significant (P<0.001 and P<0.01 respectively) global genomic hypermethylation in the gonads of male sticklebacks although the increase seen in the female gonads was not statistically significant. The male gonad effect though unexplained may potentially be an indirect response to hypomethylation in other tissues (such as the liver) and may have important implications regarding oestrogenic effects in fish. The contrasting effects of HBCD and E(2) on global DNA methylation in stickleback should contribute to the integrated risk assessment of these environmental chemicals.     

Quality assessment of composts in the Greek market: the need for standards and quality assurance

An extensive data survey and study of the Greek market for composts or products marketed as such was carried out in order to acquire a comprehensive image of the local situation, in view of the proposed operation of large municipal solid waste (MSW) composting facilities and EU legislation changes. Physical and chemical parameters (moisture, organic matter, electrical conductivity, pH and heavy metals), stability indicators (self-heating potential, germination index) and biological indicators (microbial population, pathogen indicators and selected pathogens) were analyzed for the assessment of product quality. Results revealed wide variations even within the same group of products, which is particularly significant for parameters directly related to environmental protection and public health. The heavy metal content ranged from levels exceeding the fairly lenient Greek standards to below the stringent limits for A+ class compost in Austria. About 25% of the composts examined met the heavy metal limits for the EU eco-label award. Salmonella spp. was not detected in any of the composts but Staphylococcus aureus and Clostridium perfringens were found in 17 and 96% of the composts respectively. Pathogen indicator microorganisms were present at levels above suggested limits in all the composts. The high variability of such important parameters in composts available on the Greek market suggests an urgent need for establishing quality assurance procedures and mechanisms in the country. Moreover, the wide range of limit values within EU member states suggests the need for developing EU compost quality standards, in order to harmonize the compost markets.     

Bioprocess performance,transformation pathway,and bacterial community dynamics in an immobilized cell bioreactor treating fludioxonil-contaminated wastewater under microaerophilic conditions

Environmental Science and Pollution Research - Fludioxonil is a post-harvest fungicide contained in effluents produced by fruit packaging plants, which should be treated prior to environmental...