Contamination land-derived

All anthropogenic land-derived contaminants described above are mainly introduced to the coastal sediments by atmospheric deposition and in higher quantity by riverine contributions. But these compounds can only be linked to multiple sources or widespread technical use and are therefore inappropriate to assess the discharge of the Elbe river to the German Bight. 

A large proportion of pollution in the coastal zone derived from anthropogenic contamination is a result of riverine contributions. Accordingly, the pollution of North Sea estuaries and coastal areas by organic xenobiotics is dominantly characterized by land-derived contamination. GC/MS analyses applied to sediment samples of the German Bight documented the state of organic contamination and identified specific molecular markers that are appropriate to estimate the... 

Soil plays an integral part in our lives and is inherently linked to public health. For example, many of the essential trace elements which we require in our diet to remain healthy are derived from soils and parent rock material, and low concentrations or the unavailability of these elements in soil can cause dietary deficiencies. Soils can also be contaminated with a range of potentially hazardous substances (both chemical and biological) which, if present at sufficiently elevated levels, can present a potential public health problem. For example, soils may contain elevated levels of heavy metals such as cadmium and lead which can have measurable and often severe effects on local populations. The soils of Cappadocia in central Turkey are naturally rich in fibrous asbestos-like minerals that are thought to be the cause of a rare cancer in local communities1 while exposure to the bacterium Clostridium tetani in soils can cause tetanus. Despite such examples, the effects of contaminated land have, until recently, been relatively ignored and, even today, our understanding of the mechanisms and level of risk associated with contaminated land is poor in relation to air and water. 

SEPA, Methodology to Derive Tolerable Daily Intakes. Cont ract No. N0230/2940,1999. Available at www.sepa.org.uk/contaminated.land/lmks/tdi.pdf... 

Sun, C.G., Snape, C.E., McRae, C., Falhck, A.E., 2003. Resolving coal and petroleum-derived polycyclic aromatic hydrocarbons (PAHs) in some contaminated land samples using compound-specific stable carbon isotope ratio measurements in conjrmction with molecular fingerprints. Fuel 82, 2017-2023. 

Decabromodiphenyl ether (BDE-209) is a major industrial product from the polybrominated diphenyl ethers used as flame retardants derivatives of this product have been detected in the environment. After exposure to the land surface, these contaminants adsorb on soil materials and may reach the atmosphere as particulate matter these particulates are subsequently subject to photolytic reactions. In this context, Ahn et al. (2006) studied photolysis of BDE-209 adsorbed on clay minerals, metal oxides, and sediments, under sunhght and UV dark irradiation. Dark and light control treatments during UV and sunlight irradiation showed no disappearance of BDE-209 during the experiments. Data on half-lives and rate constants of BDE-209 adsorbed on subsurface minerals and sediments, as determined by Ahn et al. (2006) and extracted from the literature, are shown in Table 16.6. 

A further area in which sequential extraction continues to be applied successfully is in assessment of the likelihood of mobilisation of metal contaminants from sediment-derived soil. When dredged sediment is used to reclaim land from the coastal margins or applied to arable soil to improve fertility, there is concern that potentially toxic elements accumulated under reducing conditions may be released on exposure to an oxygen-rich environment. Sequential extraction can be used to characterise the sediment prior to application, or to monitor changes in metal availability in the soil with time (e.g. Singh et al, 1998). 

Land Quality Management Ltd., Framework for Deriving Numeric Targets to Minimise the Adverse Human Health Effects of Long-term Exposure to Contaminants in Soil, SNIFFER, 2000, available from Foundation for Water Research, www.sniffer.org.uk. 

According to Baeza et al. (1994), the radioactive contamination of sea and land in the Antarctic regions derives from the fallout of atmospheric atomic explosions executed since 1945, apart from emissions made by nuclear and radioactive facilities. The authors examined samples of U. antartica collected near the Spanish Antarctic Base, Juan Carlos I, situated on Livingston Island in the South Shetland archipelago in... 

The Karoo Basalt, like the Kirwan Volcanics, formed from mantle-derived magma that differentiated by fractional crystallization and concurrent contamination in an open system in contact with granitic gneisses of Precambrian age. The proximity of Queen Maud Land to southern Africa in pre-Jurassic time supports the hypothesis that the Kirwan Volcanics are more closely related to the Karoo Basalt than to the basalt and dolerite of the Ferrar Group (Neethling 1972b Harris et al. 1991 Faure 2001, Fig. 5.67). 

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