Reviews of Environmental Contamination and Toxicology Volume 213

Besides being a naturally occurring element and an essential micronutrient, copper is used as a pesticide, but at generally higher concentrations. Copper, unlike organic pesticides, does not degrade, but rather enters a complex biogeochemical cycle. In the water column, copper can exist bound to both organic and inorganic species and as free or hydrated copper ions. Water column chemistry affects copper speciation and bioavailability. In all water types (saltwater, brackish water, and freshwater), organic ligands in the water column can sequester the majority of dissolved copper, and therefore, organic ligands play the largest role in copper bioavailability. In freshwater, however, the geochemistry of a particular location, including water column characteristics such as water hardness and pH, is a significant factor that can increase copper bioavailability and toxicity. In most cases, organic ligand concentrations greatly exceed copper ion concentrations in the water column and therefore provide a large buffering capacity. Hence, copper bioavailability can be grossly overestimated if it is based on total dissolved copper (TDCu) concentrations alone. Other factors that influence copper concentrations include location in the water column, season, temperature, depth, and level of dissolved oxygen. For example, concentrations of bioavailable copper may be significantly higher in the bottom waters and sediment pore waters, where organic ligands degrade much faster and dissolved copper is constantly resuspended and recycled into the aquatic system.

Organotin compounds (OTCs) are organic derivatives of tin (Sn⁴⁺) and are characterized by the presence of covalent bonds between three carbon atoms and a tin atom. The organotins are designated as mono-, di-, tri-, or tetra-organotin compounds and have the general formula (n-C₄H₉), Sn–X, where X is an anion or a group linked covalently through a hetero-atom (Dubey and Roy 2003; Okoro et al. 2011). Organotin pollution in the aquatic environment is of global concern; two triorganotin compound groups, the tributyltins and triphenyltins, are toxic to aquatic life (Fent 1996) and are used worldwide not only as biocides in antifouling paints but also as preserving agents for wood and timber, and as agricultural fungicides. These uses result in direct release to water, with consequential uptake and accumulation in aquatic fauna (Harino et al. 2000).

Shellfish farming is a common industry along European coasts. According to the 2005–2006 data from the French National Shellfish Farming Committee (CNC – Comité National de la Conchyliculture 2010; see Table 1 for a list of acronyms and abbreviations used in this chapter), Spain is the largest shellfish producer in Europe (∼270,000 t) and France ranks second, producing 200,000 t of shellfish annually. France is the leading European oyster producer, with an annual output of 130,000 t of Crassostrea gigas, and ranks fourth in the world after China, Japan, and Korea. The top three European mussel (Mytilus edulis and Mytilus galloprovincialis) producers are Spain (260,000 t), Denmark (80,000 t), and France (65,000 t). For other shellfish, the French annual output level is 15,000 t for king scallops (Pecten maximus) and a few thousand tons for Ruditapes clams (Ruditapes decussatus and Ruditapes philippinarum) and cockles (Cerastoderma edule). The economic impact of shellfish farming is considerable; despite fairly long production lead times and difficult operating conditions, shellfish farming generates annual sales of more than 650 million Euros in France, owing to its high added value.

Plants are the target of a wide range of pollutants that vary in concentration, speciation, and toxicity. Such pollutants mainly enter the plant system through the soil (Arshad et al. 2008) or via the atmosphere (Uzu et al. 2010). Among common pollutants that affect plants, lead is among the most toxic and frequently encountered (Cecchi et al. 2008; Grover et al. 2010; Shahid et al. 2011). Lead continues to be used widely in many industrial processes and occurs as a contaminant in all environmental compartments (soils, water, the atmosphere, and living organisms). The prominence of environmental lead contamination results both from its persistence (Islam et al. 2008; Andra et al. 2009; Punamiya et al. 2010) and from its present and past numerous sources. These sources have included smelting, combustion of leaded gasoline, or applications of lead-contaminated media (sewage sludge and fertilizers) to land (Piotrowska et al. 2009; Gupta et al. 2009; Sammut et al. 2010; Grover et al. 2010). In 2009, production of recoverable lead from mining operations was 1690, 516, and 400 thousand metric tons by China, Australia, and the USA, respectively (USGS 2009).

As a result of the European Parliament approving a new EU pesticide regulation (1107/2009/EC replacing directive 91/414/EEC) and a directive on the sustainable use of pesticides (2009/128/EC), in October 2009, various active ingredients are likely to be banned for use as pesticides. The use of pesticides that are carcinogenic, mutagenic, and toxic to reproduction, or that have endocrine-disrupting properties, shall no longer be authorized for use. Active ingredients that are persistent, bioaccumulative and toxic (PBT), or very persistent and very bioaccumulative (vPvB) shall be phased out as well. The decision-making process for setting test criteria for endocrine-disrupting pesticides is pending and is planned to be finalized by 2013 (EU, 2009a). The new regulation becomes effective in June 2011. According to directive 2009/128/EC, all member states are required to adopt National Action Plans for reducing the human health and environmental risks of pesticide use. The protection of the aquatic environment and drinking water supplies from pesticides, and the obligation to undertake corresponding control measures, was particularly highlighted.