Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering最新文献

Pharmaceuticals are frequently detected in natural and wastewater bodies, and are very important in environmental toxicology because of their stable nature. Advanced oxidation methods used to remove contaminants are of great benefit, especially removing pharmaceuticals unsuitable for biodegradation. In this study, imipramine was degraded by anodic oxidation and subcritical water oxidation, which are advanced oxidation methods. The determination of degradation products was performed by Q-TOF LC/MS analysis. The genotoxicity and cytotoxicity of the degradation samples were determined by the in vivo Allium Cepa method. Among the anodic oxidation samples, the lowest cytotoxicity was obtained after using 400 mA current, and 420 min of degradation time. No cytotoxic effect was observed in any subcritical water oxidation sample. However, when 10 mM hydrogen peroxide as an oxidant was used at 150 °C and the reaction time was 90 min, the subcritical water oxidation sample showed a genotoxic effect. The results of the study showed that it is crucial to evaluate the toxicity levels of the degradation products and which advanced oxidation methods are preferred for removing imipramine. The optimum conditions determined for both oxidation methods can be used as a preliminary step for biological oxidation methods in the degradation of imipramine.

The study area is located between longitude 33° 18' 00" - 33° 21' 00" E and latitude 28° 59' - 29° 01' N and covers approximately 700 km². Uranium and thorium isotopes were determined by alpha spectrometry. The activity concentrations of ²³⁸U, ²³⁴U and ²³⁵U were ranged between 245.5 ± 8.3-465.2 ± 15.2 Bq.kg^-1 with an average 345.5 ± 10.4-452.5 ± 9.3 Bq.kg^-1 and 890.5 ± 21.3 Bq.kg^-1 with an average 632.3 ± 14.9-11.40 ± 0.5 Bq.kg^-1 and 21.50 ± 1.4 Bq.kg^-1, respectively. The activity concentration of ²³²Th, ²³⁰Th and ²²⁸Th were ranged between 153.1 ± 0.3-318.1 ± 2.9 Bq.kg^-1, 149.5 ± 0.7-280.8 ± 2.2 Bq.kg^-1 and 36.9 ± 0.1-60.5 ± 0.9 Bq.kg^-1. The ²³⁰Th/²³²Th activity ratios in all samples were lower than 20, indicating that these samples have been contaminated by detrital ²³⁰Th. Th/U ratio varied between 1.3 and 2.1 with an average 1.8; all values were lower than 3.5, indicated enrichment of uranium. ²³⁴U/²³⁸U activity ratios that higher than unity indicates that an isotope of uranium has migrated within the rock. From the isotopes of uranium and thorium and their activity ratios, the isochron age for the collected samples was about 58.96 ka.

This research aims to evaluate the effect of ultrasonic processing parameters (power and sonication time), emulsion characteristics (water salinity and pH) and their interaction on oil-in-water emulsion stability for Cold Lake Blend (CLB) crude oil. Response surface methodology was used to design experimental runs, in which the parameters were investigated at five levels. Emulsion stability was evaluated by measuring creaming index, emulsion turbidity and microscopic image analysis. The effect of crude oil condition (fresh and weathered) on the emulsion stability was also investigated at the optimum sonication parameters and emulsion characteristics. The optimum condition was found at a power level of 76-80 W, sonication time of 16 mins, water salinity of 15 g/L NaCl, and pH of 8.3. Increasing sonication time beyond the optimum value had adverse effect on the emulsion stability. High water salinity (> 20 g/L NaCl) and pH (> 9) decreased the emulsion stability. These adverse effects intensified at higher power levels (> 80-87 W) and longer sonication times (> 16 mins). Interaction of parameters showed that the required energy to generate stable emulsion was within 60 - 70 kJ. Emulsion with fresh crude oil was more stable than those generated with the weathered oil.

Energy recovery from biowaste is of high significance for a sustainable society. Herein, hydrothermal treatment (HT) was applied to valorize pig manure digestate. The effects of hydrothermal operational parameters, including temperature (130-250 °C), residence time (15-90 min), and total solid (TS) concentration (10%-20%), on reducing sugar yield were investigated in this study. Among them, hydrothermal temperature was identified as the most important factor influencing reducing sugar yield, followed by the TS concentration and time. The optimal hydrothermal conditions for the pig manure digestate were 175.6 °C, 35.4 min and a TS concentration of 10% with a reduced sugar yield of 9.81 mg gTS^-1. The addition of hydrolysate could enhance methane production by 21.6-50.4% from the anaerobic digestion of pig manure than that without the hydrolysate addition. After HT, the hygienic quality, including fecal coliform number and ascaris egg mortality, was improved in the residual digestate. Antibiotics such as sulfamonomethoxine, oxytetracycline, doxycycline and sulfaclodazine in the pig manure digestate were decomposed during HT and decreased environmental risk. These findings indicated that the hydrothermal process might be an effective technique to recover energy from the digestate of livestock and poultry manure and to improve the residual digestate for subsequent utilization.

The study objective was to determine a possible association between maternal exposure to organochlorine pesticides (OCPs) and anthropometric measures at birth in group of postpartum women in urban and rural areas of Armenia. The anthropometric measures of infants were obtained from birth records and gamma-hexachlorocyclohexane (γ-HCH), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethylene, and dichlorodiphenyldichloroethane were measured in breast milk. Gas-liquid chromatography with electron capture detection was used to identify OCPs. Total OCPs and DDTs were calculated, and the anthropometrics were analyzed for sex and areas, and group differences were compared (Student's t-test). Both individual OCPs and total OCPs and DDTs were significantly higher in rural samples than in urban ones (P < 0.01-0.000), with lower and upper quartiles differing by 2.6-fold and 3.1-fold, respectively (P < 0.000). There was no association between the anthropometrics and OCPs levels in rural or urban areas. However, this does not rule out the possibility of OCPs impact on health later in life. To our knowledge, this was the first study addressing these issues in Armenia. The results obtained will provide data on the current situation regarding birth outcomes in terms of prenatal exposure to OCPs in Armenia and will contribute to the available results from previous studies.

Micro(nano)plastics are considered an emerging threat to human health because they can interact with biological systems. In fact, these materials have already been found in the human body, such as in the lungs. However, limited data are available on the behavior of these materials under biological conditions and their impact on human cells, specifically on alveolar epithelial cells. In this study, micro(nano)plastics were exposed to various simulated biological fluids (artificial lysosomal fluids and Gamble's solution) for 2-80 h. Pristine and treated plastic particles were characterized based on their surface chemistry, zeta potentials, and elemental composition. Various toxicological endpoints (mitochondrial membrane potential, lactate dehydrogenase, protein, and antioxidant levels) were examined using A549 lung carcinoma cells. The surface characteristics of the treated micro(nano)plastics and the toxicological endpoints of A549 cells were found to be influenced by the simulated biological media, specifically with high concentrations of the treated micro(nano)plastics and increasing exposure under biological conditions. Moreover, the toxicological endpoints were strongly linked to the chemistry of plastics and included multiple processes in response to the plastics; different biological pathways were obtained in artificial lysosomal fluid and Gamble's solution.