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The concentrations and distribution of β-blockers, lipid regulators, and psychiatric and cancer drugs in the influent and effluent of the municipal wastewater treatment plant (WWTP) and the effluent of 16 hospitals that discharge into the wastewater treatment plant mentioned in this study at two sampling dates in summer and winter were examined. The pharmaceutical contribution of hospitals to municipal wastewater was determined. The removal of target pharmaceuticals was evaluated in a WWTP consisting of conventional biological treatment using activated sludge. Additionally, the potential environmental risk for the aquatic receiving environments (salt lake) was assessed. Beta-blockers and psychiatric drugs were detected in high concentrations in the wastewater samples. Atenolol (919 ng/L) from β-blockers and carbamazepine (7008 ng/L) from psychiatric pharmaceuticals were detected at the highest concentrations in hospital wastewater. The total pharmaceutical concentration determined at the WWTP influent and effluent was between 335 and 737 ng/L in summer and between 174 and 226 ng/L in winter. The concentrations detected in hospital effluents are higher than the concentrations detected in WWTP. The total pharmaceutical contributions from hospitals to the WWTP in summer and winter were determined to be 2% and 4%, respectively. Total pharmaceutical removal in the WWTP ranged from 23 to 54%. According to the risk ratios, atenolol could pose a high risk (risk quotient > 10) for fish in summer and winter. There are different reasons for the increase in pharmaceutical consumption in recent years. One of these reasons is the COVID-19 pandemic, which has been going on for 2 years. In particular, hospitals were operated at full capacity during the pandemic, and the occurrence and concentration of pharmaceuticals used for the therapy of COVID-19 patients has increased in hospital effluent. Pandemic conditions have increased the tendency of people to use psychiatric drugs. It is thought that beta-blocker consumption has increased due to cardiovascular diseases caused by COVID-19. Therefore, the environmental risk of pharmaceuticals for aquatic organisms in hospital effluent should be monitored and evaluated.
相似文献This paper analyzes the impact of international oil price uncertainty on the different economic sectors (primary, secondary, and tertiary) in Mexico in the period 1993:1–2020:4 through a bivariate structural vector autoregressive (VAR) model with a generalized autoregressive conditional heteroskedasticity (GARCH) in mean to capture the impact of oil volatility on economic growth at the sectoral level of economic activity. The results show that the uncertainty of the international price of oil has a differentiated effect on the different sectors of economic activity in Mexico since it does not influence the primary sector; it negatively impacts the secondary sector, and there is mixed evidence in the tertiary sector. Additionally, evidence is provided that both positive and negative shocks to the international oil price have asymmetric effects at the sectoral level in Mexico. The results highlight the need to implement public policies, at the country level, that help mitigate the effect of uncertainty in the oil market and promote economic stability at the sector level.
相似文献This study presents the results obtained in compostability tests of organic fraction of municipal solid waste (OFMSW) digestate. The final aim was to obtain mature compost without phytotoxic effects. For the evaluation of the composting process, a novel parameter describing the performance of the composting process, the relative heat generation standardized with the initial volatile solid content (RHGVS0), was defined and evaluated at laboratory-scale. From these laboratory-scale test, the optimum operational conditions were obtained, a mixing ratio (v/v) of 1:1:0 (bulking agent:digestate:co-substrate) and with 15% of mature compost as inoculum. Subsequently, these optimum operational conditions were applied in the active phase of the composting pilot-scale reactor. The active composting stage took 7 days, subsequently a curing phase of 60 days was carried out at ambient conditions. After 30 days of curing, the mature compost showed a specific oxygen uptake rate (SOUR) of 0.14 mg O2/g VS·h, a germination index (GI) of 99.63% and a low volatile fatty acids (VFA) concentration (41.3 AcH mg/kgdm), being indicative of the good compost stability and maturity of the compost. The very good quality of the final compost obtained indicated that the RHGVS0 accurately describes the performance of the composting process.
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