某芳烃装置职业暴露苯致癌风险评估

目的:对苯长期职业性暴露下的致癌风险进行定量评价,以期为职业肿瘤等严重职业病的防控提供依据。方法:选取某大型芳烃装置作业人员为研究对象,利用目前国际上普遍采用的四段法对某芳烃装置苯长期职业性暴露下的致癌风险进行定量评价;通过对工作场所中的职业危害因素进行辨识,收集相关的动物实验、人群流行病学数据等资料,再根据工作场所中实际的环境暴露浓度,建立内暴露的剂量-反应评价多阶模型,运用蒙特卡洛模拟方法得到职业暴露人群在此环境下长期工作所存在的患癌风险概率。结果:该芳烃装置相关工作人员90%情况下苯暴露致癌风险低于2.55×10~(-4)。结论:该装置工人苯暴露的致癌风险超过可接受的致癌风险水平,需要及时采取相应措施降低风险。     

Human and organizational factors in Chinese hazardous chemical accidents: a case study of the ‘8.12’ Tianjin Port fire and explosion using the HFACS-HC

Human and organizational factors have been proven to be the prime causes of Chinese hazardous chemical accidents (HCAs). A modified version of the Human Factors Analysis and Classification System (HFACS), namely the HFACS-Hazardous Chemicals (HC), was developed to identify the human factors involved in Chinese HCAs. The ‘8.12’ Tianjin Port fire and explosion, the costliest HCA in recent years, was reanalyzed using this framework, and the results were compared with the official accident inquiry report to determine their differences related to the identification of human and organizational factors. The study revealed that interacting human factors from different levels in Ruihai Company led to this catastrophe, and the inquiry report had limitations in the identification of human factors and the guidance for similar accident prevention. This study showed the applicability of the HFACS-HC in HCA analyses as well as the necessity to recommend this approach for future HCA investigations.     

Effects of sandy desertified land rehabilitation on soil carbon sequestration and aggregation in an arid region in China

The rehabilitation of sandy desertified land in semi-arid and arid regions has a great potential to increase carbon sequestration and improve soil quality. Our objective was to investigate the changes in the soil carbon pool and soil properties of surface soil (0–15 cm) under different types of rehabilitation management. Our study was done in the short-term (7 years) and long-term (32 years) desertification control sites in a marginal oasis of northwest China. The different management treatments were: (1) untreated shifting sand land as control; (2) sand-fixing shrubs with straw checkerboards; (3) poplar (Populus gansuensis) shelter forest; and (4) irrigated cropland after leveling sand dune. The results showed that the rehabilitation of severe sandy desertified land resulted in significant increases in soil organic C (SOC), inorganic C, and total N concentrations, as well as enhanced soil aggregation. Over a 7-year period of revegetation and cultivation, SOC concentration in the recovered shrub land, forest land and irrigated cropland increased by 4.1, 14.6 and 11.9 times compared to the control site (shifting sand land), and increased by 11.2, 17.0 and 23.0 times over the 32-year recovery period. Total N, labile C (KMnO₄–oxidation C), C management index (CMI) and inorganic C (CaCO₃–C) showed a similar increasing trend as SOC. The increased soil C and N was positively related to the accumulation of fine particle fractions. The accumulation of silt and clay, soil C and CaCO₃ enhanced the formation of aggregates, which was beneficial to mitigate wind erosion. The percentage of >0.25 mm dry aggregates increased from 18.0% in the control site to 20.0–87.2% in the recovery sites, and the mean weight diameter (MWD) of water-stable aggregates significantly increased, with a range of 0.09–0.30 mm at the recovery sites. Long-term irrigation and fertilization led to a greater soil C and N accumulation in cropland than in shrub and forest lands. The amount of soil C sequestration reached up to 1.8–9.4 and 7.5–17.3 Mg ha^?1 at the 0–15 cm layer over a 7- and 32-year rehabilitation period compared to the control site, suggesting that desertification control has a great potential for sequestering soil C and improving soil quality in northwest China.     

A simple and promising route for biodiesel production from low-quality lipids

High production cost is the key issue of biodiesel industry nowadays. To decrease the cost, using low-quality lipids feedstock is the most effective way. For low-quality lipids with high content of free fatty acids, a simple and promising route is proposed to produce biodiesel. Instead of the typical two-step procedure, the esterification and transesterification processes are performed continuously by simultaneously eliminating the formed water in the reaction system with CaO powder. Investigations were carried out on the synthesis of fatty acid methyl ester and fatty acid ethyl ester. The results showed that the esterification rate reached to 99.6% for fatty acid methyl ester and 99.4% for fatty acid ethyl ester within 3–4 h, and the transesterification rate reached to 89.1 and 86.2%, respectively. Over 93 w% of feedstock oil could be transformed to biodiesel. Besides, hydrophobic CaCO₃ nanorods were also synthesized as value-added by-product. Based on the new route, the production process of biodiesel could be simplified and the production cost could be reduced.     

Emergy-based assessment on industrial symbiosis: a case of Shenyang Economic and Technological Development Zone

Industrial symbiosis is the sharing of services, utility, and by-product resources among industries. This is usually made in order to add value, reduce costs, and improve the environment, and therefore has been taken as an effective approach for developing an eco-industrial park, improving resource efficiency, and reducing pollutant emission. Most conventional evaluation approaches ignored the contribution of natural ecosystem to the development of industrial symbiosis and cannot reveal the interrelations between economic development and environmental protection, leading to a need of an innovative evaluation method. Under such a circumstance, we present an emergy analysis-based evaluation method by employing a case study at Shenyang Economic and Technological Development Zone (SETDZ). Specific emergy indicators on industrial symbiosis, including emergy savings and emdollar value of total emergy savings, were developed so that the holistic picture of industrial symbiosis can be presented. Research results show that nonrenewable inputs, imported resource inputs, and associated services could be saved by 89.3, 32.51, and 15.7 %, and the ratio of emergy savings to emergy of the total energy used would be about 25.58 %, and the ratio of the emdollar value of total emergy savings to the total gross regional product (GRP) of SETDZ would be 34.38 % through the implementation of industrial symbiosis. In general, research results indicate that industrial symbiosis could effectively reduce material and energy consumption and improve the overall eco-efficiency. Such a method can provide policy insights to industrial park managers so that they can raise appropriate strategies on developing eco-industrial parks. Useful strategies include identifying more potential industrial symbiosis opportunities, optimizing energy structure, increasing industrial efficiency, recovering local ecosystems, and improving public and industrial awareness of eco-industrial park policies.     

某铀尾矿库区周围稻田土壤不同组分对U(Ⅵ)的吸附性能分析

通过斯笃克定律提取土壤胶体,连续提取法吸附土壤中的有机质,得到土壤矿质胶体,采用比表面积(BET)法和Zeta电位对原土、土壤胶体和矿质胶体进行了表征分析,考察了溶液pH、接触时间、U(Ⅵ)初始浓度以及温度等因素对3种样品吸附溶液中U(Ⅵ)的影响性能。结果表明:原土、土壤胶体和矿质胶体的比表面积和平均孔径分别为11.5,31.1,28.8 m2/g和18.76,35.55,17.5 nm。在pH为5.5,固液比在1.0 g/L,温度为20 ℃,U(Ⅵ)初始浓度为10.0 mg/L,土壤、土壤胶体反应时间为50 min,矿质胶体反应时间为40 min时,原土、土壤胶体、矿质胶体的对U(Ⅵ)吸附率分别达到76.67%、83.03%、48.87%,吸附容量分别达到8.53,9.24,5.43 mg/g。对比研究结果可以看出,土壤中的胶体对溶液中U(Ⅵ)有着明显的吸附能力,该研究结果对进一步研究含U(Ⅵ)废水的处理及U(Ⅵ)在土壤和地下水中的迁移过程有一定的参考意义。     

HSE管理体系运行中的常见问题及对策

分析了HSE管理体系运行中存在的问题,提出了对策措施。     

Bioaccumulation of dichlorodiphenyltrichloroethanes (DDTs) in carp in a water/sediment microcosm: important role of sediment particulate matter and bioturbation

Environmental Science and Pollution Research - Sediments are reservoirs and sources of DDTs to the aquatic ecosystem. However, the role of sediment particulate matter and benthic organisms in...