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1.
•Impacts of air pollution on various body systems health in China were highlighted. •China’s actions to control air pollution and their effects were briefly introduced. •Challenges and perspectives of the health effects of air pollution are provided. The health effects of air pollution have attracted considerable attention in China. In this review, the status of air pollution in China is briefly presented. The impacts of air pollution on the health of the respiratory system, the circulatory system, the nervous system, the digestive system, the urinary system, pregnancy and life expectancy are highlighted. Additionally, China’s actions to control air pollution and their effects are briefly introduced. Finally, the challenges and perspectives of the health effects of air pollution are provided. We believe that this review will provide a promising perspective on the health impacts of air pollution in China, and further elicit more attention from governments and researchers worldwide.  相似文献   
2.
• Real ML-GFW with high salinity and high organics was degraded by O3/H2O2 process. • Successful optimization of operation conditions was attained using RSM based on CCD. • Single-factor experiments in advance ensured optimal experimental conditions. • The satisfactory removal efficiency of TOC was achieved in spite of high salinity. • The initial pH plays the most significant role in the degradation of ML-GFW. The present study reports the use of the O3/H2O2 process in the pretreatment of the mother liquor of gas field wastewater (ML-GFW), obtained from the multi-effect distillation treatment of the gas field wastewater. The range of optimal operation conditions was obtained by single-factor experiments. Response surface methodology (RSM) based on the central composite design (CCD) was used for the optimization procedure. A regression model with Total organic carbon (TOC) removal efficiency as the response value was established (R2 = 0.9865). The three key factors were arranged according to their significance as: pH>H2O2 dosage>ozone flow rate. The model predicted that the best operation conditions could be obtained at a pH of 10.9, an ozone flow rate of 0.8 L/min, and H2O2 dosage of 6.2 mL. The dosing ratio of ozone was calculated to be 9.84 mg O3/mg TOC. The maximum removal efficiency predicted was 75.9%, while the measured value was 72.3%. The relative deviation was found to be in an acceptable range. The ozone utilization and free radical quenching experiments showed that the addition of H2O2 promoted the decomposition of ozone to produce hydroxyl radicals (·OH). This also improved the ozone utilization efficiency. Gas chromatography-mass spectrometry (GC-MS) analysis showed that most of the organic matters in ML-GFW were degraded, while some residuals needed further treatment. This study provided the data and the necessary technical supports for further research on the treatment of ML-GFW.  相似文献   
3.
探究土地利用方式对长江中游小流域土壤团聚体稳定性的影响,为鄂西地区土地合理利用与管理以及土壤结构改良提供借鉴.以下牢溪小流域5种不同土地利用方式(柏树林、蔬菜地、石坎农田、撂荒地、天然林)土壤为研究对象,对比分析各土地利用方式间土壤团聚体粒径组成及稳定性差异.结果 表明:(1)柏树林、石坎农田、撂荒地和天然林土壤团聚体以>2 mm为优势粒级,平均为57.66%,蔬菜地以<0.25 mm微粒径团聚体为主,均值为60.86%;(2)林地(柏树林和天然林)土壤稳定性和抗蚀性要优于农用地(石坎农田和蔬菜地),耕地撂荒提升团聚体稳定性;(3)分形维数D与破坏率PAD、可蚀性K呈正相关,与团聚体直径(MWD和GMD)和水稳性大团聚体WR0.25呈负相关,分形维数较好反映小流域土壤团聚体的稳定性和抗侵蚀性.对流域内林区的封育是提升土壤结构稳定性的最优管理方式.  相似文献   
4.

Waterpipe (aka hookah) tobacco smokers are exposed to toxicants that can lead to oxidative DNA and RNA damage, a precursor to chronic disease formation. This study assessed toxicant exposure and biomarkers of DNA [8-oxo-7, 8-dihydro-2′-deoxyguanosine (8-oxodG)] and RNA [8-oxo-7,8-dihydroguanosine (8-oxoGuo)] oxidative damage during smoking of flavored and non-flavored waterpipe tobacco. Thirty waterpipe smokers completed two counterbalanced 2-h lab waterpipe smoking sessions (flavored vs. non-flavored waterpipe tobacco). Urinary concentrations of 8-oxodG and 8-oxoGuo and expired carbon monoxide (eCO) were measured before and after the smoking sessions. A significant increase in the urinary concentrations of 8-oxodG (from 2.12 ± 0.83 to 2.35 ± 0.91 ng/mg creatinine, p = 0.024) and 8-oxoGuo (from 2.96 ± 0.84 to 3.45 ± 0.76 ng/mg creatinine, p = 0.003) were observed after smoking the non-flavored and flavored waterpipe tobacco, respectively. Our results also showed that the mean ± SD of eCO increased significantly after smoking the flavored (from 1.3 ± 1.1 to 20.3 ± 23.6 ppm, p < 0.001) and non-flavored waterpipe tobacco (from 1.8 ± 1.2 to 24.5 ± 26.1 ppm, p < 0.001). There were no significant differences in the means of 8-oxodG (p = 0.576), 8-oxoGuo (p = 0.108), and eCO (p = 0.170) between the flavored and non-flavored tobacco sessions. Smoking non-flavored and flavored waterpipe tobacco leads to oxidative stress and toxicant exposure. Our findings add to the existing evidence about the adverse effects of waterpipe tobacco smoking (WTS) and the need for strong policies to inform and protect young people from the risks of WTS.

  相似文献   
5.
• Photocatalytic activity was improved in TiO2 thin film by rapid thermal annealing. • Photoreactor was designed for TiO2 thin film. • Considerable reusability and durability of prepared photocatalysts were studied. Un-biodegradable pharmaceuticals are one of the major growing threats in the wastewaters. In the current study, TiO2 thin film photocatalysts were designed by nanocrystal engineering and fabricated for degradation of the acetaminophen (ACE) in a photocatalytic reaction under UV light irradiation in batch and continuous systems. The photocatalyst was prepared by sputtering and then engineered by thermal treatment (annealing at 300℃ (T300) and 650℃ (T650)). The annealing effects on the crystallinity and photocatalytic activity of the TiO2 film were completely studied; it was found that annealing at higher temperatures increases the surface roughness and grain size which are favorable for photocatalytic activity due to the reduction in the recombination rate of photo-generated electron-hole pairs. For the continuous system, a flat plate reactor (FPR) was designed and manufactured. The photocatalytic performance was decreased with the increase of flow rate because the higher flow rate caused to form the thicker film of the liquid in the reactor and reduced the UV light received by photocatalyst. The reusability and durability of the samples after 6 h of photocatalytic reaction showed promising performance for the T650 sample (annealed samples in higher temperatures).  相似文献   
6.
采用气相色谱-质谱法,于2016年9月和12月对南京市2个典型地区大气中16种多环芳烃(PAHs)的质量浓度进行分析,并开展了PAHs组成特征、来源解析及人体健康风险评价研究。结果表明,工业区(六合区)和生活区(江宁区)大气(气态和可吸入颗粒态)中16种PAHs的质量浓度分别为914.82和712.27 ng/m~3,苯并[a]芘毒性等效浓度分别为274.1和309.84 ng/m~3,且呈现冬季高、秋季低的特征。比值法源解析结果表明,燃煤污染是六合区PAHs污染主要来源,而江宁区主要表现为交通污染。人体健康风险评价结果表明,六合区和江宁区人群通过大气吸入PAHs的超额致癌风险分别为5.17×10~(-5)和5.85×10~(-5),均略高于可接受水平10~(-6)。  相似文献   
7.
Environmental Science and Pollution Research - Cypermethrin (CYP) is a toxic manmade chemical compound belonging to pyrethroid insecticides contaminating the environment. Plantago major (PM) has...  相似文献   
8.
马杰  佘泽蕾  王胜蓝  邓力  孙静  刘萍  徐敏 《环境科学》2023,44(9):5264-5274
以重庆市煤矸山周边农用地土壤和农产品(玉米和水稻)为研究对象,测定土壤和农产品(玉米和水稻)中Cd含量,评估摄入农产品(玉米和水稻)对人体的潜在健康风险,并基于物种敏感性分布法(SSD)推导土壤环境基准值.结果表明,重庆煤矸山周边旱地土壤Cd含量超风险筛选值的点位占55.8%,水田土壤Cd含量超风险筛选值的点位占31.6%,土壤Cd以较高生态危害和高生态危害为主,分别占47.4%和36.8%.玉米Cd含量超标点位占4.4%,水稻Cd含量均未超标.健康风险评价表明因食用玉米和水稻摄入Cd的非致癌健康风险可忽略,食用玉米摄入Cd存在可耐受致癌健康风险,食用水稻摄入Cd存在不可耐受致癌健康风险,且玉米和水稻Cd含量敏感度最高.SSD推导出煤矸山周边旱地土壤在pH≤5.5、5.57.5时Cd的环境基准值分别为0.491、0.382、0.376和0.588 mg ·kg-1,水田土壤Cd的环境基准值为0.807 mg ·kg-1.水田土壤和旱地土壤pH≤7.5时,现行土壤标准(GB 15618-2018)相对偏严;旱地土壤pH>7.5时,现行土壤标准(GB 15618-2018)相对偏宽松.应加强煤矸山周边土壤Cd污染防治和农产品安全利用研究,并对土壤Cd环境基准值进行适当调整.  相似文献   
9.
为探究堆积煤矸石所产生的重金属的污染问题,本文以北京市门头沟5个典型矿区为研究对象,采集矸石山堆积表面风化煤矸石共45个样品,分析测试矸石样品中汞(Hg)的含量,对不同理化性质下各重金属的变化规律进行了初步探讨;利用改进BCR连续提取法,研究样品中Hg的赋存形态,分析其生物可利用性;采用富集因子法、地累积指数法、风险编码法和个体污染因子法对Hg进行有效性评价;再模拟酸雨条件下Hg的溶出特征及影响因素.结果表明,该研究区Hg的含量为0.085—0.519 mg·kg-1,均值为0.169 mg·kg-1,超过了北京市土壤背景值,超标倍数为4.225;Hg的平均富集系数与地累积指数分别为4.53和1.35,均表现为中度污染;风险编码法和次生相与原生相比值法结果显示为低风险和轻度污染,占比分别为86.67%和31.11%;Hg与Eh呈显著负相关,与含水率呈显著正相关;煤矸石中Hg的主要赋存形态为可氧化态Hg和残渣态Hg,其中可还原态Hg与可氧化态Hg存在显著负相关,TOC、p H与可还原态Hg呈显著正相关;静态淋溶试验表明,雨水酸度、粒径、固液比均...  相似文献   
10.
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