Clean-soil Air Water最新文献

During the period 2019–2020, size-segregated aerosol samples containing elemental and organic carbon (EC and OC) were investigated. These samples were collected weekly using an eight-stage cascade impactor from an urban site located at Aksaray University, Aksaray. The quantification of EC and OC was carried out through a thermal-optical transmission device. The results revealed consistent size distribution attributes of EC and OC between winter and summer. Although EC accounted for an insignificant percentage (4.4%) of particulate matter (PM) in the PM_9.0–10.0 fraction during winter, a more substantial portion of OC in the same fraction (13.4%) comprised EC. Seasonal variations were distinct for EC but not significant for OC. Strong correlations between OC and EC were observed in coarse particle fractions, indicating a common source, with weaker correlations in fine particles. The highest OC/EC ratio was in the PM_0.43–0.65 fraction, followed by PM_2.1–3.3. The ratio of OC to EC in fine PM exceeded the threshold of 15 consistently. The observation indicates that as particle size increases, there is a noticeable decline in the OC to EC ratios. Secondary organic aerosols (SOA) accounted for 60.8% (winter) and 89.8% (summer) of OC values, emphasizing the substantial impact of SOA on Aksaray's atmosphere. Both seasons exhibited a multimodal distribution of ambient OC. In winter, the EC distribution was dominated by fine particles, with a bimodal pattern (PM_1.1–2.1 and PM_0.43–0.65 peaks). Common pollutant sources, including traffic emissions, road dust, biogenic emissions, and coal combustion, were identified for both seasons in coarse and fine particle fractions. These findings underscore the importance of emission control strategies targeting fine PM in Aksaray.

Waste motor oil (WMO), which has no stable form or structure, causes major environmental problems and damage to the ecosystem once it is disposed to the environment. Because of the high toxicity of contents in such effluent, it must be treated before being discharged into the receiving environment. In recent years, the valorization and the use of waste materials to remove toxic pollutants is of great importance to researchers and diverse industries. In this study, the usability of waste welding powder (WWP) as an adsorbent for waste oil removal was investigated. For this purpose, investigating the usability of material, which is generated as industrial waste, in wastewater treatment will lead to the evaluation of waste. The effects of temperature, pH, WWP amount, and initial WMO amount were investigated. According to the adsorption studies, 1 g WWP/L of the processed adsorbent was able to effectively remove 95.05% of WMO (100 mg) at a pH of 2 at 30°C. Stereo microscopy images showed a large amount of oil adsorbed on the WWP surface. The different WWP properties were determined by adsorption isotherm (Harkins–Jura), kinetic (pseudo-second order), and thermodynamic (ΔG: −5.1 kJ mol^–1) experiments. It is thought that WWP, which is a low-cost and waste material, can be used as a promising adsorbent in WMO removal.

The increasing drought due to climate change poses a threat to issues such as safe and accessible drinking water, food safety, and protection from diseases. The provision of water supply is vital for agricultural and livestock activities, which are commonly practiced around natural ore deposits. Examining traditional “irrigation water quality” methods alone is insufficient; investigating potentially toxic metal content in the region's waters is vital, especially around metallic ore deposits. This study focused on the Kiraz district in Turkey, known for its agricultural activities, to assess the impact of geogenic water pollution on irrigation water quality and its implications for food safety and human health. Geology determines nutrient availability, water resources, and land suitability for agriculture. Conventional irrigation water quality parameters indicate groundwater suitability for irrigation in the study area, considering Na%, sodium adsorption ratio, residual sodium carbonate, permeability index, Kelly ratio, magnesium hazard, and potential salinity. However, when examining the potential toxic metal content in the region, it was determined that the values of Al ranged from 96 to 8676 ppb, Ni values ranged from 27 to 360 ppb, and Sb concentrations varied between 9 and 53 432 ppb. Utilizing geogenically contaminated water for irrigation and its indiscriminate use in livestock, dairy, and food industries can lead to foodborne illnesses (cancer, endocrine disruptors, tuberculosis, antimony spots, thyroid tumors, goiter, neurologic and cardiovascular diseases) that endanger human health. The use of low-quality water throughout the agricultural sector and food production chain increases food safety risks.

Surface water is renowned for its natural organic matter, constituting approximately 45% of total dissolved organic carbon (DOC) which can be removed in water treatment plants. However, residual DOC in water can react with chlorine to form several carcinogenic disinfectant by-products (DBPs). This study aimed to examine the molecular weight of organic fractions dissolved in three different water sources that act as precursors to the formation of DBPs species. The coagulants used were Al- and Fe-based, frequently used in water treatment plants to remove organic fractions. Characterization of DOC in source water served as the first step in determining the performance of both coagulants in terms of organic properties. The results showed that the selected surface waters had similar DOC characteristics, including biopolymers, humic substances, building blocks, and a low molecular weight. These fractions contributed to the formation of trihalomethanes (THMs) and haloacetic acids (HAAs). The Fe-based coagulant was more effective than the Al-based coagulant in removing all organic fractions and reducing THMs compared to HAAs. Furthermore, one-way ANOVA analysis showed a significant difference in the average removal of organic fractions and DBP species between the Fe-based and Al-based coagulants. The Fe-based coagulant showed higher efficiency in removing biopolymers, dibromochloromethane, and chlorodibromoacetic acid than the Al-based coagulant. In contrast, the Al-based coagulant had better performance in reducing dibromo HAA and tribromo HAA. Both coagulants had no significant difference in extracting other organic fractions or DBPs species.

Due to human activities, the overabundance of regional nitrogen/phosphorus (N/P) has a huge impact on ecological environment worldwide. It is necessary to comprehensively understand the human-induced N/P input and spatiotemporal variations of nutrients in a river. As the adjustment to the spatial structure of Beijing, the Beijing's subcenter is an important strategic position in promoting the coordinated development of Beijing–Tianjin–Hebei. In this study, the dynamic changes of ammonia nitrogen (NH₃-N) and total phosphorus (TP) from 2012 to 2022 were analyzed, then the net anthropogenic N input (NANI) and net anthropogenic P input (NAPI) was estimated in the Beijing's subcenter. The results showed that both NH₃-N and TP had an overall downward trend with a three-stage pattern. The NANI and NAPI declined from 5.68 × 10⁴ and 0.95 × 10⁴ to 0.78 × 10⁴ and 0.15 × 10⁴ kg km⁻² per year, respectively. The chemical fertilizers input accounted for the largest part at 53–81% of NANI and 49–80% of NAPI. There were high values of N and P input in the southeast of Tongzhou, and the fluxes of N and P were positively correlated with the input of anthropogenic N and P in the Chaobai River Basin (Tongzhou District) and the Beiyun River Basin (Tongzhou District). This study would provide the foundation for setting priorities and enacting more targeted N/P management strategies in the Beijing's subcenter.

Portunus trituberculatus is important in coastal benthic communities and a favorite seafood for coastal residents. However, microplastics have been detected in different tissues of P. trituberculatus, but the toxicological effects of micro- and nanoplastics (MNPs) on the different tissues of P. trituberculatus have not been reported. We found that the lethal effect of MNPs on P. trituberculatus is not obvious, but they can stimulate the body's stress response. The responses of P. trituberculatus tissues to MNPs are different, which may be due to differences in enzyme reactions between tissues and organs. Compared with microplastics (MPs), nanoplastics (NPs) have a more significant physiological and metabolic stress effect on P. trituberculatus because of their smaller particle size. In summary, plastic particles have physiological stress effects on the physiological metabolism of P. trituberculatus, which may be closely related to the plastic's particle size and concentration.