Reimermerritt3301

Soil has been identified as an important source of exposure to a variety of chemical and biological contaminants. Toxoplasma gondii is one of those potential biological contaminants associated with serious health effects in pregnant women and immunocompromised patients. Gardening or consumption of homegrown vegetables may present an important route of T. gondii infection via accidental ingestion of soil. In the Netherlands, there is quantitative information on the risk of T. gondii infection via meat products, but not on the risk of infection through soil. The objective of this study was to develop a quantitative microbial risk assessment (QMRA) model for estimating the risk associated with T. gondii exposure via accidental soil ingestion in the Netherlands. In order to obtain the needed information, a magnetic capture method for detection of T. gondii oocysts in soil samples was developed, and T. gondii DNA was detected using qPCR targeting the 529 bp repeat element. The method was shown to provide 95% probability of detection (95% CI 88-100%) when at least 34 oocysts are present in 25 g of soil. T. gondii DNA was detected in 5 of 148 soil samples with interpretable results (3%, 95% CI 1.5-7.7%). Results for 18 samples were not interpretable due to PCR inhibition. The estimated amount of oocysts presented in qPCR positive samples was quantified by a linear model, and the amount varied from 8 to 478 in 25 g of soil. The estimated incidence rate of T. gondii infection from the QMRA model via soil varied from 0.3 to 1.8 per 1000 individuals per day. Several data gaps (e.g., soil contamination/ingestion and oocysts viability) have been identified in this study, the structure of the model can be applied to obtain more accurate estimates of the risk of T. gondii infection via soil when data become available.The anaerobic treatment of food wastes (FW) for resource recovery has been extensively studied. However, the information on the traits of functional genes and enzymes for substrates metabolisms and their associations with microbial community are little. In this study, the influences of eggshells conditioning on the substrates metabolism for volatile fatty acids production (VFAs) in the process of FW fermentation were investigated at genetic levels by using the metatranscriptomic approach. The obtained results suggested that the critical genes involved in the carbohydrate and protein metabolisms (i.e. pgmB, GPI, glsA, pyrB and etc.) were up-regulated in the eggshell-conditioned reactor, which were beneficial to the bioconversion of macromolecule organics during FW fermentation. Moreover, the functional genes related with the intermediate products metabolism (i.e. pyruvate acid, butanoate) also exhibited differential genetic expression levels, which resulted in the alteration of microbial metabolic pathways and contributed to the acetic and butyric acids accumulation. In addition, a preliminary association of microbial distribution and genetic expressions was analyzed. The distinct distribution of microbial community in different FW fermentation systems affected the corresponding microbial contribution to those genetic expression levels of metabolic enzymes involved in VFAs production. This study would provide new insights of the underlying mechanism of VFAs promotion in the eggshell-conditioned FW fermentation process from the perspectives of substrates metabolisms at genetic and functional traits.Using manure compost (MC) as a substitute for chemical fertilizer (CF) has been regarded as an effective strategy to promote sustainable crop production. The application of biochar in compost production could significantly mitigate the emission of gaseous pollutants and improve compost quality. However, comprehensive investigations of the environmental performance of crop production using CF, MC, and biochar-amended MC strategies are scarce. Therefore, in this study, wheat production using four fertilizer strategies, including CF, MC, and biochar-amended MC with biochar addition rates of 5% (MCB5) and 10% (MCB10), was comparatively assessed in terms of their environmental performance using the life cycle assessment (LCA) method. Compared to the CF strategy, the majority of midpoint impact categories and all assessed damage categories (except for human health and resources in MCB10) were mitigated using the compost strategies. check details Furthermore, as the biochar application rate increased, the biochar-amended MC strategies remarkably decreased the impacts on the global warming potential, stratospheric ozone depletion, and land use, and greatly increased the impacts on ozone formation (human health), fine particulate matter formation, and terrestrial acidification. Overall, biochar-amended MC with a biochar addition rate of 5% (MCB5) is recommended as the optimal strategy due to its relatively low environmental impact. Moreover, combined with the results of the sensitivity analysis, biogenic air pollutant emissions derived from the compost and biochar production stages were identified as the most important hotspots contributing to the undesirable environmental impacts. These findings advance our understanding of the environmental performance of wheat production using biochar-amended MC.For the last forty-five years (from 1974 to present) ferroalloy production in Bagnolo Mella, Northern Italy, has generated particulate emissions enriched in potentially toxic metals and metalloids including arsenic (As), lead (Pb) and manganese (Mn). Of these, Mn is unique in that it has a significant background concentration and is seldom studied as a contaminant but is potentially a significant toxin derived from dusts regionally. Here we examine the distribution, redistribution, speciation and bioavailability of the Mn-contaminated top soils affected by atmospheric emissions adjacent to the ferroalloy plant. Four sites, variably located in the study area in terms of both distance and direction from the plant, were considered as representative of increasing levels of industrial influence. Soil profiles showed that metal concentrations (measured by X-ray fluorescence) varied considerably by location, i.e. higher in the sites closer to the plant and also at the surface level, although distributed throughout the top 15 cm, suggesting appreciable redistribution possibly due to soil mixing or infiltration.