Structural and functional diversity of microbial communities from a lake sediment contaminated with trenbolone, an endocrine-disrupting chemical

Application of biochar in estrogen hormone-contaminated and manure-affected soils: Impact on soil respiration, microbial community and enzyme activity

Biochar as a soil amendment has been proposed for enhancing carbon sequestration and manure-borne hormone contaminant remediation. However, little is known about the ecological risk of biochar application in the soil with hormone contamination. This study investigated the influence of biochar in three manure-impacted soils contaminated with estrogen hormones, natural estrogen 17β-estradiol and synthesized estrogen 17α-ethinylestradiol in a microcosm experiment. Specifically, microbial respiration was periodically determined during microcosm incubation while microbial community phospholipid fatty acids and activities of nutrient (C, N, P, S) cycling related enzymes (β-glucosidase, urease, phosphodiesterase, arylsulfatase) were characterized after the incubation. Results showed that the manure-impacted soils with high SOC generally had greater total microbial biomass, ratios of fungi/bacteria and Gram-positive bacteria/Gram-negative bacteria, and phosphodiesterase activity, but lower urease activity. Additionally, hormones stimulated microbial respiration and biomass, while had little impact on activity of the enzymes. On the other hand, biochar showed negative priming effect by significantly decreasing total microbial biomass by 8.7%-26.4%, CO₂ production by 16.6%-33.5%, and glucosidase activity by 27.1%-41.0% in the three soils. Biochar significantly increased the activity of phosphodiesterase, showed no impact on arylsulfatase, while decreased the activity of urease. Overall, the study suggests that when used in hormone remediation in manure-impact soils, biochar could improve phosphodiesterase activity, but may decrease soil microbial activity and the activity of soil glucosidase and urease.

The Bioaccumulation and Biodegradation of Testosterone by Chlorella vulgaris

: In the present study, the accumulation and degradation of testosterone by Chlorella vulgaris were studied. The results showed that C. vulgaris has a significant ability to eliminate testosterone by bioaccumulation and biodegradation, and during the 96 h experimental period, the data demonstrated that the accumulation of testosterone followed a sigmoidal accumulation pattern. At the end of the experiment, the bioconcentration percentages of testosterone by C. vulgaris in the high-concentration group and the low-concentration group were 11.49 ± 2.78% and 40.10 ± 1.98%, respectively, and the biodegradation percentages of testosterone were 69.64 ± 4.33% and 42.48 ± 1.92%, respectively. The rate of biodegradation of testosterone by C. vulgaris mainly depended on the relative initial concentration of testosterone. When the relative initial concentration of testosterone increases, the degradation may gradually change from zero-order kinetics to second-order kinetics.

A critical review of the environmental occurrence and potential effects in aquatic vertebrates of the potent androgen receptor agonist 17β-trenbolone

Trenbolone acetate is widely used in some parts of the world for its desirable anabolic effects on livestock. Several metabolites of the acetate, including 17β-trenbolone, have been detected at low nanograms per liter concentrations in surface waters associated with animal feedlots. The 17β-trenbolone isomer can affect androgen receptor signaling pathways in various vertebrate species at comparatively low concentrations/doses. The present article provides a comprehensive review and synthesis of the existing literature concerning exposure to and biological effects of 17β-trenbolone, with an emphasis on potential risks to aquatic animals. In vitro studies indicate that, although 17β-trenbolone can activate several nuclear hormone receptors, its highest affinity is for the androgen receptor in all vertebrate taxa examined, including fish. Exposure of fish to nanograms per liter water concentrations of 17β-trenbolone can cause changes in endocrine function in the short term, and adverse apical effects in longer exposures during development and reproduction. Impacts on endocrine function typically are indicative of inappropriate androgen receptor signaling, such as changes in sex steroid metabolism, impacts on gonadal stage, and masculinization of females. Exposure of fish to 17β-trenbolone during sexual differentiation in early development can greatly skew sex ratios, whereas adult exposures can adversely impact fertility and fecundity. To fully assess ecosystem-level risks, additional research is warranted to address uncertainties as to the degree/breadth of environmental exposures and potential population-level effects of 17β-trenbolone in sensitive species. Environ Toxicol Chem 2018;37:2064-2078. Published 2018 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Occurrence, fate and risk assessment of androgens in ten wastewater treatment plants and receiving rivers of South China

Androgens are one class of steroids that could cause endocrine disrupting effects in aquatic organisms. However, little information is available about androgens in wastewater treatment plants (WWTPs) with different treatment technologies. Here we investigated the occurrence, removal, and fate of fourteen natural and synthetic androgens in ten WWTPs of Guangdong province, south China. The results showed detection of ten androgens in the influents of the ten WWTPs, with concentrations up to 4650 ng/L (androsta-1,4-diene-3,17-dione). But only three androgens androsta-1,4-diene-3,17-dione, 4-androstene-3,17-dione and 17β-boldenone were detected in the final effluents of the ten WWTPs, while six androgens androsta-1,4-diene-3,17-dione (N.D. to 43.0 ng/g), 4-androstene-3,17-dione (2.06-42.7 ng/g), epi-androsterone (N.D. to 506 ng/g), testosterone (0.29-4.24 ng/g), 17β-boldenone (N.D. to 2.05 ng/g) and methyl testosterone (N.D. to 0.70 ng/g) were found in activated sludge. The aqueous phase removal rates for most androgens in the WWTPs exceeded 95% except for 4-androstene-3,17-dione with its removal rates varying between 79.5% and 100%. The removal of androgens in the WWTPs could be attributed mainly to biodegradation while removal by precipitation, volatilization, sludge absorption and oxidation was very limited. Eight androgens were also found in five receiving rivers. The risk quotients of some androgens (androsta-1,4-diene-3,17-dione, 4-androstene-3,17-dione, methyl testosterone, 17α-trenbolone) exceeded 1 in the receiving rivers, showing high risks to aquatic organisms. Further studies are needed to understand the origin of these high risk androgens and ecological effects.

Eutrophication may compromise the resilience of the Red Sea coral Stylophora pistillata to global change

Environmental stressors are adversely affecting coral reef ecosystems. There is ample evidence that scleractinian coral growth and physiology may be compromised by reduced pH, and elevated temperature, and that this is exacerbated by local environmental stressors. The Gulf of Aqaba is considered a coral reef refuge from acidification and warming but coastal development and nutrient effluent may pose a local threat. This study examined the effects of select forecasted environmental changes (acidification, warming, and increased nutrients) individually and in combination on the coral holobiont Stylophora pistillata from the Gulf of Aqaba to understand how corals in a potential global climate change refugia may fare in the face of local eutrophication. The results indicate interactions between all stressors, with elevated nutrient concentrations having the broadest individual and additive impacts upon the performance of S. pistillata. These findings highlight the importance of maintaining oligotrophic conditions to secure these reefs as potential refugia.

Environmental and human health challenges of industrial livestock and poultry farming in China and their mitigation

Driven by the growing demand for food products of animal origin, industrial livestock and poultry production has become increasingly popular and is on the track of becoming an important source of environmental pollution in China. Although concentrated animal feeding operations (CAFOs) have higher production efficiency and profitability with less resource consumption compared to the traditional family-based and "free range" farming, they bring significant environmental pollution concerns and pose public health risks. Gaseous pollutants and bioaerosols are emitted directly from CAFOs, which have health implications on animal producers and neighboring communities. A range of pollutants are excreted with the animal waste, including nutrients, pathogens, natural and synthetic hormones, veterinary antimicrobials, and heavy metals, which can enter local farmland soils, surface water, and groundwater, during the storage and disposal of animal waste, and pose direct and indirect human health risks. The extensive use of antimicrobials in CAFOs also contributes to the global public health concern of antimicrobial resistance (AMR). Efforts on treating the large volumes of manure generated in CAFOs should be enhanced (e.g., by biogas digesters and integrated farm systems) to minimize their impacts on the environment and human health. Furthermore, the use of veterinary drugs and feed additives in industrial livestock and poultry farming should be controlled, which will not only make the animal food products much safer to the consumers, but also render the manure more benign for treatment and disposal on farmlands. While improving the sustainability of animal farming, China also needs to promote healthy food consumption, which not only improves public health from avoiding high-meat diets, but also slows down the expansion of industrial animal farming, and thus reduces the associated environmental and public health risks.

Assessing water quality by ratio of the number of dominant bacterium species between surface/subsurface sediments in Haihe River Basin

Sedimentary microorganisms can be used as a sensitive indicator of integrated aquatic environment quality assessment and indicate long-term water quality or toxicity. According to the Chinese National Standards of GB 3838-2002 and GB 18918-2002, the comprehensive water quality in Haihe River Basin has been described. Results showed that the comprehensive water quality in 6 sites, 4 sites, and 20 sites were good, bad, and medium. Furthermore, 162 dominant bacterial species were identified in surface and subsurface sediments in the 30 sampling sites. As revealed by two initial models constructed by logistic regression, the comprehensive water quality exhibited a pattern from good to bad as the ratio of the number of dominant bacterial species in surface sediments to that in subsurface sediments increased from 1 to 2.1. This finding possibly bridged a traditional gap between aquatic microbe indicators and water quality assessment or monitoring techniques.

The effects of estrone and 17β-estradiol on microbial activity and bacterial diversity in an agricultural soil: sulfamethoxazole as a co-pollutant

Estrogens and veterinary antibiotics (VAs) that are contained in animal excrements are spread into agricultural soil when using animal wastes on farmland. The impacts of VAs on soil health have already been well documented. However, there is limited knowledge regarding the influence of estrogens, particularly the combined effects of estrogens and VAs, on the soil microbial community. In this study, a short-term analysis (11 days) of the effect of the estrogens estrone and 17β-estradiol on soil microbial activity and on bacterial community structure was performed using a dehydrogenase activity (DHA) test and a PCR-denaturing gradient gel electrophoresis (DGGE) assay, respectively. Meanwhile, the potential influence of the VA sulfamethoxazole (SMX) as a co-pollutant on the effects of estrogens was examined. It was found that (1) estrone and 17β-estradiol biodegraded within hours in non-sterilized soil, even in the presence of up to 100mg/kg SMX. (2) Estrone or 17β-estradiol alone markedly promoted soil DHA and stimulated the growth of partial bacteria strains, which were demonstrated as new or more intensive bands in DGGE profiles relative to the control treatment at the later incubation period. (3) The presence of SMX as a co-pollutant at concentrations of 10 and 100mg/kg removed the stimulatory effects of estrogens on soil DHA and significantly reduced the DHA level to below the level of the untreated control. SMX also depressed the appearance of bacterial bands that were stimulated by estrone or 17β-estradiol alone. Moreover, the coexistence of SMX and estrogens induced additional bacterial bands, which may be tolerant strains. Overall, these results imply that the load of estrogens might serve as nutrient substances for soil microorganisms, whereas VAs as co-pollutants would cause a shift of these positive effects toward a significant threat to the natural soil microbial community. Therefore, the removal of VAs in animal waste is essential to ensure the safe use of animal waste in agricultural land.

Perinatal androgenic exposure and reproductive health effects female rat offspring

Environmental contaminants known as endocrine-disrupting chemicals (EDC) have been associated with adverse effects on reproductive processes. These chemicals may mimic or antagonize endogenous hormones, disrupting reproductive functions. Although preliminary studies focused on environmental estrogens, the presence of compounds with androgenic activity has also been described. This study examines exposure of female pregnant and lactating rats to low doses of androgens and assesses potential effects on female offspring. Pregnant Wistar rats were exposed to testosterone propionate (TP) at doses of 0.05, 0.1, or 0.2 mg/kg or corn oil (vehicle), subcutaneously, to determine influence on reproductive health of female offspring. There were two exposure groups: (1) rats treated from gestational day (GD) 12 until GD 20; and (2) animals treated from GD 12 until the end of lactation. Perinatal exposure to TP produced increased anogenital distance after birth and diminished height of uterine glandular epithelium at puberty in animals exposed to 0.2 mg/kg. However, these alterations were not sufficient to impair sexual differentiation and normal physiology of the female rat reproductive tract.

Quinone profiles of microbial communities in sediments of Haihe River-Bohai Bay as influenced by heavy metals and environmental factors

A total of 11 sediment samples were collected from the sites along Haihe River-Bohai Bay, with site 1 at the beginning of Haihe River and site 11 in Bohai Bay, about 150 km away from site 1. Quinone profiles were used for the analysis of microbial community as influenced by pollutants in water and sediments, such as heavy metals, and other environmental factors. Nineteen species of quinones were found at site 1 while only six species at sites 10 and 11. Both the diversity of quinone species (DQ) and the number of quinones were higher in the sediments from Haihe River and the near-sea area of Bohai Bay than in those from the deep-sea area. The β diversity values were significantly higher, while Jaccard indexes of similarity were much lower among non-contiguous pairs of sites as compared with the contiguous ones. Cluster analysis indicated that quinone profiles may be grouped into two main clusters (sites 1-7 and sites 8-11), and there were higher similarities within the groups than between groups. Quinone species composition varied at different sites. Ubiquinones such as UQ-8, UQ-9, and UQ-10 and menaquinones such as MK-6, MK-7, MK-8 were isolated from all the sites and accounted for the largest proportions. Pearson correlation analysis revealed that both the number of quinone species and DQ correlated positively with total organic carbon contents in water and sediments, but negatively correlated with salinity and electroconductivity and did not correlate significantly with heavy metal contents in water.

Variable distributional characteristics of substrate utilization patterns in activated sludge plants in Kuwait

The objective of this study was to determine the magnitude of microbial functional potential and community structure between three different WWTPs using the Lorenz curve method and to find the effect of seasonal variation on patterns of substrate utilization. Lorenz curve method was sensitive enough to detect short-term changes in microbial functional diversity between Riqqa, Umm Al-Haiman and Al-Jahra activated sludge systems and showed seasonal variations of the utilized carbon sources. Gini coefficient ranged from 0.21 to 0.8. Lorenz curves seemed particularly suitable to present microbial heterogeneity in term of inequality and to highlight the relative contribution of low-and high functional diversity for the three different types of mixed liquors. Correlation analysis of the experimental data show that the complement of the Gini coefficient was strongly and positively correlated with the Shannon index (r(xy)=0.89), evenness (r(xy)=0.91), and AWCD (r(xy)=0.95) at the 95% level of significance (alpha=0.05).