Falkdesai9345
Microbial metabolic functions were predicted using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The results indicated that xenobiotics biodegradation and metabolism, carbohydrate metabolism, and amino acid metabolism were the three most abundant metabolic pathways of the microbes. The abundances of these metabolic functions were also altered by the DCM concentration. Diffusion coefficient (D) is an important parameter for prediction of micropollutant uptake kinetics in passive samplers. Passive samplers are nowadays commonly used for monitoring trace organic pollutants in different environmental matrices. Samplers utilising a hydrogel layer to control compound diffusion are gaining popularity. In this work we investigated diffusion of several perfluoroalkyl substances, currently used pesticides, pharmaceuticals and personal care products in 1.5% agarose hydrogel by measuring diffusion coefficients using two methods a diffusion cell and a sheet stacking technique. Further, diffusion coefficients in water were measured using Taylor dispersion method. The sheet stacking method was used to measure D at 5, 12, 24, and 33 °C in order to investigate temperature effect on diffusion. Median D values ranged from 2.0 to 8.6 × 10-6 cm2 s-1 and from 2.1 to 8.5 × 10-6 cm2 s-1 for the diffusion cell and sheet stack methods respectively. For most compounds, the variability between replicates was higher than the difference between values obtained by the two methods. Rising temperature from 10 to 20 °C increases the diffusion rate by the factor of 1.41 ± 0.10 in average. In water, average D values ranged from 3.03 to 10.0 × 10-6 cm2 s-1 and were comparable to values in hydrogel, but some compounds including perfluoroalkyl substances with a long aliphatic chain could not be evaluated properly due to sorptive interactions with capillary walls in the Taylor dispersion method. Sampling rates estimated using the measured D values were systematically higher than values estimated from laboratory sampler calibration in our previously published study, by the factor of 2.2 ± 1.0 in average. Coal mine derived acid mine drainage (AMD) is formed when oxygenated water infiltrates mine voids and oxidizes FeS phases, generating acidic fluid rich in heavy metals, polluting thousands of miles of streams. Existing remediation options are cost-prohibitive and difficult to sustain. In some cases, AMD flows over previously pristine soil in thin sheets over terrestrial surface, enhancing AMD aeration and Fe(II) oxidizing activities, leading to oxidative Fe(II) precipitation from AMD, without any human intervention. Since robust Fe(II) biooxidation occurs in the mixture of intruding AMD and pristine soil, understanding the effects of chemically variant AMD can be exploited for effective Fe(II) removal. We hypothesized that chemistry and microbiology of AMD intruding pristine soil on surface would influence the development of Fe(II) oxidizing capabilities. Therefore, to investigate the response of pristine soil to the addition of AMD varying in chemical and microbial characteristics, we mixed soil with a near-neutral and moderately acidic AMD, in separate incubations. Incubations with near-neutral AMD developed microbial Fe(II) oxidation activities after 10 days. However, Fe(II) oxidation in moderately acidic AMD incubations was mostly abiotic. 16S rRNA gene sequences and metabolic functional prediction (Tax4Fun) analysis of near-neutral AMD and soil mixture indicated development of taxonomically different communities capable of activities similar to microorganisms in a mine void. In conclusion, results indicate that AMD chemistry and microbiology affects development of Fe(II) biooxidation. Therefore, understanding of the effect of AMD chemistry on the development of FeOB activities in soil can be exploited to design site-specific and sustainable solutions. Oil sands process-affected water (OSPW) is a byproduct of bitumen extraction in the surface-mining oil sands industry in Alberta, Canada. Organic compounds in OSPW can be acutely or chronically toxic to aquatic organisms, so part of a long-term strategy for remediation of OSPW is ageing of water in artificial lakes, termed end-pit lakes. BaseMine Lake (BML) is the first oil sands end-pit lake, commissioned in 2012. At the time of its establishment, an effects-directed analysis of BML-OSPW showed that naphthenic acids and polar organic chemical species containing sulfur or nitrogen contributed to its acute lethality. However, the chronic toxicity of these same chemical fractions has not yet been investigated. In this work, the short-term fathead minnow reproductive bioassay was used to assess endocrine-system effects of two fractions of BML-OSPW collected in 2015. One of the fractions (F1) contained predominantly naphthenic acids, while the other (F2) contained non-acidic polar organic chemical species. Exposure of minnows to F1 or F2 at concentrations equivalent to 25% (v/v) of the 2015 BML-OSPW sample (5-15% of the 2012 BML-OSPW sample) did not alter reproductive performance, fertilization success, or concentrations of sex steroids in female or male minnows. DNA Repair inhibitor Additionally, there were no significant differences in fertility, hatching success, or incidence of morphological indices of embryos collected on day 7 or 14 from exposed breeding trios. However, exposure of male fathead minnow to 25% (v/v) intact 2015 BML-OSPW resulted in a significantly greater hepatosomatic index. Exposure of fathead minnow to refined fractions of dissolved organic chemicals in 2015 BML-OSPW, or a 25% (v/v) of the intact mixture did not affect fertility or fecundity as measured by use of the 21-day reproductive bioassay. These data will be useful in setting future threshold criteria for OSPW reclamation and treatment. To assess the toxic effects of 3-(4-Methylbenzylidene) camphor (4-MBC) at environmentally relevant concentrations on the reproduction and development of Japanese medaka (Oryzias latipes), adult paired medaka (F0) were exposed to 5, 50, and 500 μg/L 4-MBC for 28 d in the current study. The fecundity and fertility were significantly decreased at 500 μg/L 4-MBC (p less then 0.05). Histological observations showed that spermatogenesis in F0 males was significantly inhibited at 50 and 500 μg/L 4-MBC, similar to the effects obtained with all treatments of plasma 11-ketotestosterone (p less then 0.05). Moreover, the plasma vitellogenin and estradiol levels in F0 females were significantly increased at 5 μg/L 4-MBC (p less then 0.05). All the transcripts of hypothalamic-pituitary-gonadal (HPG) axis-related genes tested in the brains and gonads of males were significantly increased at all treatments, similar to the effects obtained for erα, erβ and vtg in the livers and in contrast to those found for arα in the livers (p less then 0.