The IOMC organisations: a source of chemical safety information

Status of POPs accumulation in the Yellow River Delta: From distribution to risk assessment

The Yellow River Delta (YRD) is a large region of China with complex pollution sources and a long history of environmental deterioration. Despite this, relatively little data exists on the status of important contaminants of concern in this region. Here, we review the literature on the status of key persistent organic pollutants (POPs) of concern including organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) in the YRD. Sources, source identification methods, and spatial distribution patterns are presented. Additionally, POPs contamination levels reported in the literature were evaluated against popular regulatory limits worldwide to form a basis for overall environmental health. Our review determined that OCPs in the YRD originated mainly from current pesticide use and past agricultural pesticide application. Sources of PAHs included petrochemical inputs, coal fired plants, and wood combustion. PCB levels were impacted by the petrochemical industry as well as waste disposal of PCB containing equipment. OCPs exhibited a spatial distribution pattern that increased along the urban-rural gradient, while the opposite was seen for PAHs and PCBs. Comparisons of POPs contamination levels in the YRD with popular regulatory limits suggest that the extent of PCB contamination all mediums (sediment, soil, water, and biota) exceeded that of PAHs and OCPs. Overall pollution levels in the YRD seem to be in control; however, levels from heavily polluted point sources raise numerous concerns about the ecological health of the region and require more attention from regulatory authorities.

Sources, concentrations and risk factors of organochlorine pesticides in soil, water and sediment in the Yellow River estuary

The environmental occurrence, sources and risk factors of organochlorine pesticides (HCHs and DDTs) and their isomers or metabolites were studied using comprehensive surveys (including soil, surface water, groundwater and sediment sampling) conducted in the Yellow River Delta (YRD). HCHs and DDTs were all detected in multi environmental media. Compared with reported organochlorine pesticide values in China and abroad and with related environmental quality standards, the concentrations of HCHs and DDTs were generally at low levels in the YRD. Composition of OCPs (DDT metabolites and HCH isomers) showed that DDTs in the multiple environments of the YRD not only came from residues of dicofol but also from atmospheric deposition, while HCH pollution results from the historical usage of a mixture of technical HCH and lindane. Furthermore, the sum of Excess Lifetime Cancer Risk (∑ELCR) exposure to HCHs exceeded the generally acceptable risk level of 1.0E-06 recommended by the USEPA for carcinogenic chemicals.

Mining environmental toxicology information: web resources

Environmental toxicology is the study of the ecological effects of anthropogenic substances released into the environment. It is a relatively diverse field addressing impacts to aquatic and terrestrial organisms and communities. The determination of potential risk associated with toxic agents is of interest to government regulators, industry, researchers, private organizations and citizen groups. In assessing the ecological risk associated with a chemical stressor, it is important to establish linkages between likely exposure concentrations and adverse effects to ecological receptors. To do so requires access to reliable information resources. The proper application of such data requires familiarity with the scientific literature and keeping abreast of new and emerging issues as well as state-of-the-art research findings and methods. In addition, an understanding of government regulations as they relate to environmental issues is also of primary interest. The advent of the Web has made these tools accessible at computer desktops. This review focuses on currently available free Web resources related to environmental toxicology, specifically those which address available empirical data sources, predictive tools and publications of interest such as standard test methods, guidance documents and governmental regulations.

WEB resources for pesticide toxicology, environmental chemistry, and policy: a utilitarian perspective

Information about pesticides has grown exponentially over the last four decades and is marked by a diversity of sources including government, universities, environmental advocates, and industry. The internet has made access to this unprecedented amount of information faster than ever, but judging the validity and usefulness of the information is problematic. To avoid turning this discussion of web resources for pesticide information into a narrative about a personal 'top ten' list, a utilitarian perspective of resources useful to a research, educator, and risk communicator is elucidated. Useful web sites are fit into the context of information needed for risk assessment, which includes hazard identification, dose-response relationships, exposure assessment, and risk characterization. In addition resources for pesticide policy and regulations are considered. Specific ways in which the sites are useful are discussed along with information about site updating and validation of information.