Project description:Despite recent knowledge of the potential environmental impact that compounds present in municipal wastewater effluents, including contaminants of emerging concern (CECs), may have, the implications of fish exposure to this contaminant mixtures are not completely understood. The effects caused by effluent CECs may be subtle and diverse, thus the need for sensitive and comprehensive tools such as gene expression to detect such responses. In this study, we conducted laboratory exposures that examined plasma concentrations of vitellogenin (VTG), changes in secondary sexual characteristics and gene expression in sexually mature male fathead minnows (Pimephales promelas) exposed to environmentally realistic (0.5%) and higher (5%) concentrations of municipal wastewater effluents. Secondary and primary treated effluents were used. Several of the 32 CECs investigated were detected, including pharmaceuticals, personal care products, hormones, current use pesticides and industrial compounds. The percent of males with detectable levels of VTG was higher in fish exposed to effluent treatments. An increased number of males with changes in secondary sexual characteristics (e.g. development of ovipositors), was observed in fish exposed to 5% effluent treatments. Gene expression data indicated that overall expression patterns were characteristic to each effluent. Higher numbers of differentially expressed genes were observed in fish exposed to primary treated effluent when compared to controls. Differentially expressed genes belonged to several functional categories, including xenobiotic metabolism, estogenicity and energy/metabolism processes. Gene expression data provided information to understand some of the mechanisms behind the effects observed at higher biological levels. To investigate gene expression responses resulting from exposure to POTW effluents, two laboratory experiments were conducted using effluent from San Diego (Point Loma; SD) and Los Angeles (Hyperion; LA). The LA effluent received secondary treatment and the SD effluent received advanced primary treatment. Treatments used during exposures consisted of negative controls (moderately hard water), positive controls (E2), and 0.5% and 5% effluent concentrations. The 0.5% concentration of effluent represented an environmentally realistic exposure level. The 5% effluent concentration represented a higher level at which we expected biological responses. The exposures lasted 14 days. Treatments: EFFHa = 5% primary treated effluent EFFHb = 5% secondary treated effluent EFFLa = 0.5% primary treated effluent E2a = Estradiol, positive control for primary effluent E2b = Estradiol, positive control for secondary effluent CTRLa = Moderately hard water, negative control for primary effluent CTRLb = Moderately hard water, negative control for secondary effluent
Project description:To investigate gene expression changes in fish by the secondary effluent (directly released to environment) of a waterwater treatment plant in Tucson, Arizona, zebrafish larvae with 5-day exposure to the original (1x) or half (0.5x) concentration of the effluent were analyzed using Agilent G2519F-026437 Zebrafish Oligo Microarray.
Project description:In this study, we intended to use trans-omics approach and some clinical examinations to systematically evaluate the human health risks of source of drinking water, effluent of conventional treatment and effluent of advanced treatment by quaternized magnetic microsphere in a drinking water plant.
Project description:The Patancheru area near Hyderabad in India is recognized as a key link in the global supply chain for many bulk drugs. A central treatment plant receives wastewater from about 90 different manufacturers and the resulting complex effluent has contaminated surface, ground and drinking water in the region. Ecotoxicological testing of the effluent has shown adverse effects for several organisms, including aquatic vertebrates. In an attempt to start investigating how exposure to effluent-contaminated water may affect humans and other terrestrial vertebrates, rats were tube-fed effluent. Results from microarray and quantitative polymerase chain reaction assays indicated, however, no marked effects on hepatic gene expression after five days exposure. Neither did a clinical analysis of blood serum constituents used as biomarkers for human disease reveal any significant changes, nor were there any effects on weight gain. Taken together, we could not find evidence for any acute toxicity in the rat; however, we cannot rule out that higher doses of effluent or a longer exposure time may still be associated with risks for terrestrial vertebrates.
Project description:Patancheru, near Hyderabad, India, is a major production site for the global bulk drug market. About 90 manufacturers send their wastewater to a common treatment plant in Patancheru. Extraordinary high levels of a wide range of pharmaceuticals have recently been demonstrated in the treated effluent. As little as 0.2% of this effluent can strongly reduce the growth rate of tadpoles, but the underlying mechanisms of toxicity are not known. To begin addressing how the effluent affects aquatic vertebrates, rainbow trout (Oncorhynchus mykiss) were exposed to 0.2% effluent for five days. Several physiological endpoints, together with effects on global hepatic gene expression patterns, were analyzed. The exposed fish showed both an induction of hepatic cytochrome P450 1A (CYP1A) gene expression, as well as EROD activity. Clinical blood chemistry analyses revealed an increase in plasma phosphate levels, which in humans indicates impaired kidney function. Several oxidative stress-related genes were induced in the livers, however, no significant changes in antioxidant enzyme activities or in the hepatic glutathione levels were found. Furthermore, estrogen-regulated genes were slightly up-regulated following exposure, and moderate levels of estriol were detected in the effluent. This study identifies changes in gene expression triggered by exposure to a high dilution of the effluent, supporting the hypothesis that these fish are responding to chemical exposure. The pattern of regulated genes may contribute to the identification of mechanisms of sub-lethal toxicity, as well as illuminate possible causative agents.