Biotransformation rates of xenobiotic compounds in relation to enzymes activities: A critical review

Many biotransformation reactions and many activities of enzymes involved in the biotransformation of xenobiotics in fish have been described. Therefore, the prediction of biotransformation of (other) xenobiotics through literature data seems to be possible. However, very few data allow correlation of in vitro enzyme activities with in vivo biotransformation rates. This is mainly due to a lack of quantitative data. Suggestions are made for future research, which may help to relate enzyme activities and biotransformation in fish.     

Trace Element Contaminants in Sediments From the Noaa National Status and Trends Programme Compared to Data From Throughout the World

The National Oceanic and Atmospheric Administration's (NOAA) National Status and Trends (NS&T) Programme has analyzed samples of surface sediment collected at almost 300 coastal and estuarine sites throughout the United States since 1984. the overall distributions for concentrations of each element are approximately lognormal allowing a definition of geometric means and of “high” concentrations as those exceeding the mean plus one standard deviation of the lognormal distribution. Those mean and “high” concentrations should be useful for comparing the NS&T data set and with other reports on sediment contamination. A world-wide data set, constructed from data in the literature, was summarized in an identical manner. It was found, after excluding locally extreme values, that the NS&T and world-wide data sets yielded very similar mean and “high” concentrations for Cu, Ni, Pb and Zn. Chromium was the sole element showing higher summary statistics in the NS&T data set, a result attributed to NS&T sampling in areas of naturally (not contaminated) elevated Cr content. It remains undetermined, however, why the world-wide data set, even with exclusion of “hot spots”, yielded higher means and “highs” for Cd, Hg, As, and Ag.     

The Monitoring of UK Sewage Sludge Disposal Sites

In recent years there has been an increase in the intensity and frequency of environmental monitoring surveys at UK sewage sludge disposal sites. These have been carried out by the regulatory authorities and by the licensees. in order to ensure maximum efficiency, a coordinated and harmonised programme of monitoring has been developed. the programme concentrates on sediment chemical and biological quality but also includes assessments of water and fish quality

In England and Wales the Ministry of Agriculture, Fisheries and Food is the regulatory authority and the Water Authorities are the licensees. the Ministry's first priority is the collection of samples for temporal trend analysis but in addition, infrequent surveys are made to check the status of the disposal site and surrounding areas. in the periods between status surveys, regular spatial surveys designed to define the area of impact are carried out by the Water Authorities.     

The temporal changes of the concentration level of typical toxic organics in the river sediments around Beijing

In this study, the current situation of five types of toxic organics and endocrine disrupters in the sediments of rivers around Beijing, i.e., polycyclic aromatic hydrocarbons (PAHs), phthalic acid esters (PAEs), organic chlorinated pesticides (OCPs), estrogens (Es), and bisphenol A (BPA), which included 56 contaminants, was analyzed and compared with that registered by the historical literatures. The ecological risks were also assessed. The total concentration of PAHs, PAEs, OCPs, Es, and BPA ranged from 232.5 ng·g^–1 to 5429.7 ng·g^–1, 2047.2 ng·g^–1 to 18051.5 ng·g^–1, 4.5 ng·g^–1 to 11.7 ng·g^–1, 18.1 ng·g^–1 to 105.2 ng·g^–1, and 36.3 ng·g^–1 to 69.6 ng·g^–1, respectively. Among these five types of organic compounds, the concentration levels of PAHs and OCPs have decreased significantly in the last ten years, while those of PAEs and Es had an upward trend compared with the previous studies. BPA still remained at a moderately high level, as it was ten years ago. The risks of the PAEs in all of the sample sites, and fluoranthene, benzo[a]anthrene, and benzo[a]pyrene in the Wenyu River sediment, were relatively high. These results supplemented the database of toxic organics’ concentration levels in the sediments of Beijing rivers.

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居住小区道路雨水径流消减潜力分析

居住小区建设的不断发展在缓解城市居住问题的同时,也给城市环境带来了一系列的负面效应,而减轻这些负效应的关键就在于尽可能的减少小区的不透水地表面积以使地表径流量得到消减。道路作为居住区地表的重要组成部分,在解决上述问题中应当重点考虑。本文以南京市桌新建居住区为例,从减少道路面积和改变地面铺装方式两个角度来寻找减少小区内部不透水铺装面积的方法,并估算了由此所能消减的地表径流量。根据实例分析可知,通过这两种方法可以切实有效的减少小区不透水面积进而减少雨水的径流量。     

表面处理清洁生产线的研发

介绍了中国电器科学研究院近期研制开发的电镀、氧化等金属表面处理新型生产线。对生产线各相关系统进行研究,通过改进与创新,达到清洁、节能、智能化等目的。     

湿法消解-原子荧光光谱法同时测定地表水中的砷和汞

为提高检测效率、降低检测成本、提高检测的准确性,采用硝酸消解水样,断续流动进样,在KBH_4-酸体系中、最佳的仪器试验条件下,用原子荧光光谱法同时测定地表水中的砷和汞。实验结果表明:砷、汞检出限分别为0.109、0.0026μg/L,线性范围分别为0～40μg/L和0～2μg/L,精密度都是1.4%,加标回收率分别为93.5%～107%和96.0%～104%。表明该检测方法检出限低、干扰性小、精密度高、测定结果稳定,能够满足地表水中砷和汞同时测定要求。     

地表水特定项目优化检测技术研究

对地表水中特定项目指标的检测技术进行了优化研究,根据检测目标化合物的结构性质和色谱分析手段的兼容性,对前处理方法和分析手段进行了优化整合,提出了特定项目的解决方案,提高了工作效率,对切实保障饮用水源安全有实际意义.     

2016—2021年四川省地表水体中铀的放射性水平及健康风险评价

为调查四川省地表水体中放射性物质铀（U）的含量,评价居民摄入地表水体中U导致的健康风险,在四川省主要地表水系中共设置23个监测断面,于2016—2021年检测了U的放射性水平,并根据健康风险评价模型对居民的健康风险进行评估。结果表明：四川省地表水体中U的质量浓度为0.16～3.6 μg/L,参照《生活饮用水卫生标准》（GB 5749—2022）,均合格;不同年份、不同地表水体中U的放射性水平间的差异均无统计学意义（P＞0.05）;不同水期U的放射性水平间的差异有统计学意义（P＜0.05）。各年龄组通过饮水、水体浸没途径摄入U所致总年均待积有效剂量均＜0.1mSv;对各年龄段居民的总致癌风险为4.18×10^-9 ～2.24×10^-8 ,均低于世界卫生组织（WHO）和国际放射防护委员会（ICRP）发布的最严格控制限值。全省主要地表水体中U对各年龄组都是安全的。     

WDXRF法测定污染土壤和沉积物中金属元素

采用土壤稀释〖CD*2〗波长色散X射线荧光光谱法（WDXRF）测定污染土壤和沉积物样品中的重金属和As,解决了由于元素含量高超出工作曲线测定范围产生较大误差的问题,确保测定结果的有效性。通过标准物质、实际样品的方法比对评估方法的准确度和精密度,该方法测定标准样品中多个无机元素的分析结果均满足国标准确度要求,与常规ICP OES法测定值一致,相对偏差均＜4.5%。