Assessing the inhalation cancer risk of particulate matter bound polycyclic aromatic hydrocarbons (PAHs) for the elderly in a retirement community of a mega city in North China

Assessment of the health risks resulting from exposure to ambient polycyclic aromatic hydrocarbons (PAHs) is limited by the lack of environmental exposure data among different subpopulations. To assess the exposure cancer risk of particulate carcinogenic polycyclic aromatic hydrocarbon pollution for the elderly, this study conducted a personal exposure measurement campaign for particulate PAHs in a community of Tianjin, a city in northern China. Personal exposure samples were collected from the elderly in non-heating (August–September, 2009) and heating periods (November–December, 2009), and 12 PAHs individuals were analyzed for risk estimation. Questionnaire and time-activity log were also recorded for each person. The probabilistic risk assessment model was integrated with Toxic Equivalent Factors (TEFs). Considering that the estimation of the applied dose for a given air pollutant is dependent on the inhalation rate, the inhalation rate from both EPA exposure factor book was applied to calculate the carcinogenic risk in this study. Monte Carlo simulation was used as a probabilistic risk assessment model, and risk simulation results indicated that the inhalation-ILCR values for both male and female subjects followed a lognormal distribution with a mean of 4.81?×?10^?6 and 4.57?×?10^?6, respectively. Furthermore, the 95 % probability lung cancer risks were greater than the USEPA acceptable level of 10^?6 for both men and women through the inhalation route, revealing that exposure to PAHs posed an unacceptable potential cancer risk for the elderly in this study. As a result, some measures should be taken to reduce PAHs pollution and the exposure level to decrease the cancer risk for the general population, especially for the elderly.     

Sorption specificity and desorption hysteresis of gibberellic acid on ferrihydrite compared to goethite,hematite, montmorillonite,and kaolinite

Environmental Science and Pollution Research - The pesticide gibberellic acid (GA3) is a potential endocrine disruptor and environmental toxin; therefore, research into its environmental fate is...     

炼油厂含油污泥处理与处置技术综述

分门别类地阐述了近十年来国内外含油污泥的一些处理处置技术.按回收原油方法分,含油污泥处理技术包括了热处理技术、溶剂萃取技术、冻融技术;按含油污泥的综合利用技术分,包括了含油污泥的建材利用、燃料制作、焦化处理以及作为其它工业原料利用;按含油污泥处理处置方法,生物法、焚烧、稳定化/固化、填埋等方法.介绍了这些方法的技术原理与试验效果.     

论湿地及其保护和利用——以洪湖湿地为例

本文阐述了湿地的定义,并以洪湖为例,从水文、土壤、生物组成和系统的功能等方面论述了湿地生态系统的特征,进而提出湿地保护和利用问题。文章最后指出:只有对湿地进行充分的保护,才能使其持续地为人类提供财富。     

天津港的发展与环保规划设想

阐述了天津港的发展前景，对港区环境质量现状和环保设施作了全面的调研，根据可持续发展的思想，提出了与天津港发展相应的环保规划设想。     

鸭绿江口再悬浮沉积物中汞的释放

报道了鸭绿江河口区悬浮物中汞含量随潮态的变化，并通过实验模拟研究了鸭绿江下浮污染沉积物中汞在海水作用下的释放机理。结果表明，在河口区，高潮时悬浮物中汞含量低于低潮时的含量，其原因除了海水中氯离子对悬浮物中汞的络合作用以及碱金属和碱土金属离子的交换作用外，还由于悬浮沉积物中汞主要以有机物，腐殖酸结合态存在，碱性海水能溶解腐殖酸，从而导致与腐殖酸结合态汞的释放。     

序批式活性污泥法工艺MATLAB仿真模型的初步建立

序批式活性污泥法工艺（SBR）是目前应用很广的一种污水处理工艺，本文在国际水协会（IWA）的ASM1模型的基础上，建立了SBR工艺反应模型，通过模型检验可发现，该模型能较好地模拟SBR工艺反应中的微生物处理过程，具有很大的发展前景。     

膜压法在自然水体研究中的应用

膜压法在自然水体中的应用较为广泛。文章综述了膜压及膜面积可作为自然水体中有机物含量的表征，也可作为水体受污染程度大小的一种判据。在研究表面膜的表面物理性质与化学组分之间联系的过程中，发现表面膜中有能够主宰表面膜性质的标准物质存在。由于这些标准物质主导了表面膜的表面物理性质，因此。寻找这些标准物质，并将它们的表面物理性质特征化，这也是今后工作中研究的方向。     

乌江下游德江县喀斯特石漠化及其防治

基于TM影像解释和实地考察,查清了德江县石漠化面积为70 693 hm~2、占全县土地总面积的34．1％,划分了石漠化强度(中度以上的石漠化面积占全县总面积的16．6％),明确了德江县石漠化的空间分布格局;分析了德江石漠化的危害;从地形地貌、岩性、降水、耕种方式等方面探讨了石漠化的成因,最后提出了德江县石漠化综合防治对策。