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Persistent organic pollutants (POPs) are ubiquitous environmental contaminants that are not readily degraded in the environment. They are typically lipophilic, bioaccumulating in tissues of aquatic organisms and biomagnifying in freshwater and marine food webs. POPs include a wide range of halogenated legacy contaminants [e.g., polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs), chlordanes, hexachlorobenzene (HCB)] that have been banned because of their toxicity to humans and wildlife; compounds such as polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzodioxins (PCDDs) that can be produced naturally (e.g., through forest fires and volcanic eruptions) or through industrial processes; and chemicals of emerging concern [e.g., polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds]. Although many POPs are no longer being released into the environment, they continue to be reported at toxic concentrations in fish, and there is much that is not yet understood about their modes of action and their ecological effects on aquatic habitats. This chapter reviews current information on (1) uptake and metabolism of these compounds by fish; (2) their biological effects, including their actions as endocrine disruptors, reproductive, developmental, neurological, immunological, and metabolic toxicants and carcinogens; and (3) recent efforts to evaluate the ecological risks of exposure to such compounds on fish populations and aquatic communities. [Copyright &y& Elsevier]

Organic chemicals that are sufficiently persistent are capable of undergoing long-range transport and travel great distances from their sources through the atmosphere. Those organic chemicals that are more efficiently scavenged from the atmosphere in alpine environments than in the surrounding areas can become enriched in mountains, i.e. are found in higher than background concentrations at higher altitudes. This is confirmed by measurements in snow and glacial ice as well as in the waters and aquatic and lotic biota of mountains. Those organic contaminants that exhibit increasing concentrations with elevation are often also those expected to exhibit bioaccumulation and biomagnification, i.e. to achieve higher concentrations at higher trophic levels. As the effects of long-term exposure to many of these chemicals is not yet understood, and as they are – or are structurally related to – known toxins, the presence of higher-than-background concentrations of certain POCs in alpine environments is of considerable concern. [ABSTRACT FROM AUTHOR]

The objectives of this investigation were to determine risk from old pesticide storehouses and to assess phytoremediation technology for potential implementation to reduce risk in the Republic of Moldova. A risk assessment method was proposed and 16 storehouse sites were evaluated in the Hȋncești district. More than 60% of the sites showed middle to high risk levels from POPs (persistent organic pollutants) pesticides. One site with a high risk level was chosen for a phytoremediation case study under field conditions. Several cultivated plants were evaluated for determination of pesticide extraction efficiency: maize (Zea mays L.), zucchini (Cucurbita pepo L. var. pepo), pumpkin (C. pepo L. var. pepo), carrot (Daucus carota L.), and sorghum (Sorghum bicolor L. Moench). Analytical measurements of POPs in soil, plants and other environmental media determined these old storehouse sites remain highly polluted after the removal of obsolete chemical stockpiles, and additional remediation actions are needed. Phytoremediation can be used for remediation of polluted sites; however, it needs to be designed based on local conditions. The best phytoextraction efficiency was shown by zucchini and pumpkin. Time required for agricultural phyto-remediation might be long and require utilization of complex approaches that consider use of biotechnology as well as native and perennial plants to develop a successful strategy. [ABSTRACT FROM AUTHOR]

Many human activities cause the release of synthetic hazardous substances into the marine environment or the redistribution of naturally occurring substances. This can result in the contamination of the marine environment with substances that have a deleterious effect on marine life. This chapter selects and discusses some pollutants that are currently of concern in the marine environment. [ABSTRACT FROM AUTHOR]

The Lagoon of Venice has been receiving discharges of many classes of persistent organic pollutants (POPs) that have been accumulating in sediments and marine organisms and might represent an indirect threat to human health. In particular, the intensive harvesting of Manila Clam (Tapes philippinarum) and other traditional fishing activities carried out in the lagoon represent the highest direct source of risk for human health. This paper presents an overview of sources and fates of dioxins, polychlorinated biphenyls and hexachlorobenzene in the Lagoon of Venice. Pollution data of environmental matrices (atmospheric depositions, water and sediments) and biota (clams) of the lagoon are presented for describing the environmental and biological contamination. Evidences on possible human contamination are derived from recent data of POPs in mother milk and blood serum of Venetians with different work exposure and food habits. This overview evidences a critical environmental state for some areas of the Venice Lagoon and confirms a non-negligible human health risk for regular shellfish and fish consumers. The overview supports the need for keeping some lagoon areas restricted to fishing and for maintaining the current situation under monitoring. [ABSTRACT FROM AUTHOR]

Turkey signed the Stockholm Convention on May 23, 2001, with the objective of protecting human health and environment, focusing on eliminating or reducing releases of 12 POPs, the ˵Dirty Dozen″. Turkey has developed its National Implementation Plan (NIP) as a Party to the Stockholm Convention. The NIP sets out how the Stockholm Convention is being implemented in Turkey and outlines the next steps to be taken in the management of POPs. A number of experts, representative of the institutions, ministries, universities, Scientific and Technical Research Council of Turkey – Marmara Research Center, and nongovernmental organizations took part in preparing the inventory and preparation of the NIP. [ABSTRACT FROM AUTHOR]

The paper represents the results of an overall analysis and review of the current state in the field of persistent organic pollutants (POPs) management in Ukraine, as well as the experiences gained in realization of the recent activities aimed at collecting and processing the data on different sources of the wastes consisting of or contaminated with hazardous chlorine-containing substances, as a significant input to the development of a National Plan for implementation of the Stockholm Convention on POPs. It is summarized the last achievements in developing managerial tools and a methodological approach to developing the national inventories of available and potential POPs-containing wastes and contaminated sites. [ABSTRACT FROM AUTHOR]

Persistent organic pollutants (POPs) are persistent, bioaccumulating, toxic chemicals with a potential for long-range transport. POPs can be exchanged between all environmental media, and a range of dynamic processes thus determines their environmental fate. Therefore it is a challenge to include POPs in model studies since the processes are not all fully understood in detail. Traditionally, the environmental fate of POPs has been modeled using multi compartment mass-balance models, whereas in recent years atmospheric chemistry-transport models have also been applied. These two ways of modeling the environmental fate of POPs will be briefly described and an example of a study of the environmental fate of α-hexachlorocyclohexane using an atmospheric chemistry transport model in a study will be given. The model is shown to simulate the atmospheric concentrations and variability on both the short and long term of one of the most abundant POPs with an acceptable accuracy. However, there are still several environmental processes that are not fully understood. This is a further challenge for environmental POP modeling studies and recommendations for future research is therefore outlined. [ABSTRACT FROM AUTHOR]

The impact of persistent organic pesticides represents one of the major environmental problems as reported in several studies and reflected in some mandatory actions at the inter-governmental level. In particular, isomers of Hexachlorocyclohexane (HCH), like many others Organochlorine Pesticides (OCPs), are of human health and environmental concern due to their persistence in the biosphere. In industrialised countries, Lindane (the ν-isomer of HCH with insecticide effects) has been widely used in the past. As a consequence, large quantities of HCH isomers without insecticide effects (α-, β-, δ- and ε), discarded during the purification of Lindane, have been disposed for years into dumps around industrial sites. Nowadays, such uncontrolled disposal practices imply a great risk of environmental contamination, possibly threatening animals and humans by food chains transfer and bio-accumulation. In 2005, dairy cow farms in the Province of Rome (Italy) were threatened due to environmental contamination of the Sacco River by HCHs. As a case study, all components of the dairy cow production system undergoing agroenvironmental pollution crisis, were investigated with the aim to analyze the main critical points. Five dairy farms were involved in the research. Data regarding the contamination by HCHs of soils, forages, bovine milk and blood serum are reported. Soil and forage samples (mainly maize, alfalfa and ryegrass) were taken in different places near the Sacco River, on the basis on irrigation practiced and flooding conditions. All samples were analyzed by Gas Cromatography using an Electron Capture Detector. Soil contamination by HCHs was found higher nearby than away the river (p < 0.01) with a great incidence of outflow risk (p < 0.01), while no differences were observed on the basis of irrigation practices. In alfalfa samples higher concentration of HCHs than in ryegrass were detected, with a greater plant/soil apparent partition factor. Differences in milk contamination by β-HCH among dairy farms (p < 0.01) and sampling time were found (p < 0.05). In many cases, the β-HCH content of milk resulted above the EU limit (0.003 mgβ-HCH/kg), posing serious hazard for human consumption due to chronic toxicity of that isomer. Differences in milk β-HCH concentration were found related to lactating phase and parity. A linear regression between blood serum and milk β-HCH concentration was observed (r2 = 0.919, p < 0.05). Furthermore, β-HCH as a trace was detected in blood sera when milk levels fell below the analytical limits, indicating the usefulness of blood serum HCH content as an early indicator of animal exposure. Results obtained from the case study highlighted the needing for further researches at wider level, due to the strong impact of persistent organic pesticides on rural environment and human food chain. [ABSTRACT FROM AUTHOR]