Increased urinary 8-hydroxy-2��-deoxyguanosine levels in workers exposed to di-(2-ethylhexyl) phthalate in a waste plastic recycling site in China

Background

Di-(2-ethylhexyl) phthalate (DEHP) is a common plasticizer used in industrial and diverse consumer products. Animal studies indicate DEHP caused developmental, reproductive, and hepatic toxicities. However, human studies of the potential effects of DEHP are limited.

Methods

The exposed site with a history of over 20 years of waste plastic recycling was located in Hunan Province, China. The reference site without known DEHP pollution source was about 50 km far away from the exposed site. In this study, 181 workers working in plastic waste recycling and 160 gender?Cage matched farmers were recruited. DEHP concentrations in water and cultivated soil samples, serum thyroid-stimulating hormone, malondialdehyde (MDA), superoxide dismutase (SOD), urinary 8-hydroxy-2??-deoxyguanosine (8-OHdG), and micronuclei frequency in human capillary blood lymphocytes were analyzed.

Results

Mean levels of DEHP were greater in environment at the recycling site than at reference site (industry wastewater for the exposed: 42.43 ??g/l; well water: 14.20 vs. 0.79 ??g/l, pond water: 135.68 vs. 0.37 ??g/l, cultivated soil: 13.07 vs. 0.81 mg/kg, p?p?p?Conclusions The occupational DEHP exposure might contribute to oxidative deoxyribonucleic acid damage in the male workers.     

Sequential accelerated solvent extraction of polycyclic aromatic hydrocarbons with different solvents: performance and implication

Sixteen USEPA priority polycyclic aromatic hydrocarbons (PAHs) extracted by Soxhlet extraction (S-PAHs) with dichloromethane and routine accelerated solvent extraction (A-PAHs) with 1:1 toluene/methanol, respectively, were investigated in 24 soil samples from two cities in the center of the Pearl River Delta, South China. Polycyclic aromatic hydrocarbons, methylphenanthrene and perylene, in two soils, two sediments, and an immature oil shale were also sequentially extracted by accelerated solvent extraction (ASE) with each of four different organic solvents for three times. The A-PAHs' concentrations are 2.41 times the S-PAHs' concentrations. For sequential three ASEs, PAHs in the first extract account for 56 to 67% of their total concentrations in the sequential three extractions and toluene displays the best extraction performance among the four solvents. Diagnostic ratios of PAHs in Soxhlet extraction, routine ASE, and sequential ASE with each solvent for a given sample are very similar, suggesting their identical petrogenic and pyrogenic sources in the soils and sediments. But the PAH ratios for the shale have an obvious petrogenic origin. The perylene/5-ring PAH ratios indicate a diagenetic source, especially in the shale and sediments. The correlation analysis shows that A-PAHs/S-PAHs is better associated with the contents of total organic carbon (TOC) than those of black carbon (BC). The above results indicate the significant petrogenic origin of PAHs and the important effect of organic matter on their extraction and distribution in the investigated field soils/sediments.     

Nitrogen mass flow in China's animal production system and environmental implications

China's economic boom in recent decades has stimulated consumer demand for animal products and consequently, a vast expansion in animal production. From 1978 to 2006, the number of animals increased by 322% for pigs, 209% for poultry, and 2770% for dairy cattle. The objective of the present study was to quantify nitrogen mass flow in China's animal production system at the national scale and to elucidate potential environmental implications. A comprehensive analysis was performed combining statistical records with data from the scientific literature and supplemental survey information. Results indicate that approximately 18 Mt of N flowed through the Chinese animal production system in 2006. Nitrogen input to the system was from various feed materials, including 6.8 Mt (38% of total) from roughage, 4.4 Mt (24%) from byproducts, 2.3 Mt (13%) from cereal grains, and 1.6 Mt (9%) each from crop residues and oilseed cakes, with the remaining N (16%) obtained from other feedstuffs. Nitrogen outputs from the system included edible animal products (2.4 t, 13% of total), nonedible animal parts (e.g., bones, skins) (3.8 Mt, 21%), and excreta (12 Mt, 66%). At the national level, the excreta would average 28 Mg (as excreted) and 90 kg N ha(-1) of cropland. However, at the provincial level, it varied from 1 Mg ha(-1) (5 kg N ha(-1)) in Qinghai to 97 Mg ha(-1) (243 kg N ha(-1)) in Sichuan. In regions with excreta in the intermediate rate (e.g., Hebei Province, 115 kg N ha(-1)) or high rare (e.g., Sichuan Province, 243 kg N ha(-1)), animal manure contributes significantly to nutrients polluting groundwater and/or surface waters. It is crucial for China to develop and implement proper management practices to maximum the beneficial use of the 12 Mt excreta N while minimizing its environmental footprint.     

油田清洁生产审核重点的确定

油田开发是一项由地下勘探与钻井、地面油气集输及水处理等多种工艺组成的复杂的系统工程,各工艺过程能源和资源的消耗,对环境的影响因素、范围和程度都不尽相同。文章按照清洁生产审核重点确定应遵循的原则,体现具有针对性、可为审核提供定量准确基础数据的特点,从原料(采出液等)、辅助材料和产品(外输原油等)的数量、主要生产设备运行情况和工艺流程、能源和资源消耗量、各类污染物的排放量等方面,探讨了油田在清洁生产审核过程中确定审核重点的方法。     

许昌市发制品行业的清洁生产调查

发制品行业是以人发、人造纤维等为原材料进行假发加工的行业。许昌市发制品的生产过程大致可分为两个阶段:漂染和前后处理。漂染过程用水量大,产生的废水难以处理。其中过酸、氧化、染色配置的溶液使用一次后直接排放,不符合清洁生产要求,且所排放的溶液可考虑中和多次利用。漂染过程水资源消耗量大,废水产生量大,没有考虑废水综合利用。按清洁生产的要求在以上环节可通过技术革新和设备改造得以改进。     

水环境中有机污染物对藻类毒理性的探讨

近年来,环境中的有机污染物对生态环境的破坏日益加剧,并严重威胁到了人类的生存和发展。藻类作为初级生产者,是整个生态系统物质循环和能量流动的基础,因此研究水环境中有机污染物对藻类的毒理性,对于环境污染的监测具有深远的意义。就有机污染物对藻类的毒性机理、藻类对有机污染物的敏感度等问题的研究现状进行综述,并对藻类在环境监测方面的应用前景进行展望。     

Agricultural ammonia emissions inventory and spatial distribution in the North China Plain

An agricultural ammonia (NH₃) emission inventory in the North China Plain (NCP) on a prefecture level for the year 2004, and a 5 × 5 km² resolution spatial distribution map, has been calculated for the first time. The census database from China's statistics datasets, and emission factors re-calculated by the RAINS model supported total emissions of 3071 kt NH₃-N yr⁻¹ for the NCP, accounting for 27% of the total emissions in China. NH₃ emission from mineral fertilizer application contributed 1620 kt NH₃-N yr⁻¹, 54% of the total emission, while livestock emissions accounted for the remaining 46% of the total emissions, including 7%, 27%, 7% and 5% from cattle, pigs, sheep and goats, and poultry, respectively. A high-resolution spatial NH₃ emissions map was developed based on 1 × 1 km land use database and aggregated to a 5 × 5 km grid resolution. The highest emission density value was 198 kg N ha⁻¹ yr⁻¹.     

Dissipation of polycyclic aromatic hydrocarbons (PAHs) in the rhizosphere: Synthesis through meta-analysis

Polycyclic aromatic hydrocarbons (PAHs) are widespread and persistent organic pollutants with high carcinogenic effect and toxicity; their behavior and fate in the soil-plant system have been widely investigated. In the present paper, meta-analysis was used to explore the interaction between plant growth and dissipation of PAHs in soil based on the large body of published literature. Plants have a promoting effect on PAH dissipation in soils. There was no difference in PAH dissipation between soils contaminated with single and mixed PAHs. However, plants had a more obvious effect on PAH dissipation in freshly-spiked soils than in long-term field-polluted soils. Additionally, a positive effect of the number of microbial populations capable of degrading PAHs was observed in the rhizosphere compared with the bulk soil. Our meta-analysis established the importance of the rhizosphere effect on PAH dissipation in variety of the soil-plant systems.     

Assessment of metal contaminations leaching out from recycling plastic bottles upon treatments

Background, aims, and scope  

Heavy metal contaminants in environment, especially in drinking water, are always of great concern due to their health impact. Due to the use of heavy metals as catalysts during plastic syntheses, particularly antimony, human exposure to metal release from plastic bottles has been a serious concern in recent years. The aim and scope of this study were to assess metal contaminations leaching out from a series of recycling plastic bottles upon treatments.     

微乳法制备Fe-TiO_2纳米晶复合体及光催化性能

采用微乳法制备铁掺杂TiO2纳米晶（Fe-TiO2）复合体,通过热重-差热（TG-DTA）、X射线衍射（XRD）、扫描电镜（SEM）和紫外漫反射光谱（DRS）等对其结构和形态进行表征;以亚甲基蓝溶液（MB）为标准模拟降解物,对Fe-TiO2,纯TiO2和P25光催化降解性能进行评价。结果表明,Fe-TiO2的光催化活性明显〉P25,原因是Fe掺杂不仅能抑制TiO2晶粒生长,提高TiO2的热稳定性和比表面积,而且能够拓展TiO2的吸收波长范围至可见光区,提高了Ti3＋离子浓度,降低了光生载流子的复合几率。