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Endocrine disrupting (ED) chemicals are compounds that alter the normal functioning of the endocrine system, potentially causing disease or deformity in organisms and their offspring. Pesticides are used widely to kill unwanted organisms in crops, public areas, homes and gardens and medicinally to kill parasites. Many are proven or suspected to be EDs. Ancient physiological similarities between different vertebrate groups suggest that disorders observed in wildlife may indicate risks to humans. This makes accurate risk assessment and effective legislation difficult. In this paper, the hazardous properties of pesticides which are known to have ED properties are reviewed in order to assess the implications for risk assessment. As well as data on sources of exposure in the United Kingdom (UK) an assessment of the evidence on the health effects of ED pesticides is also included. In total, 127 have been identified from the literature and their effects and modes of action are listed in this paper. Using the UK as a case study, the types and quantities of pesticides used, and their methods of application are assessed, along with their potential pathways to humans. In the UK reliable data are available only for agricultural use, so non-agricultural routes of pesticide exposure have been poorly quantified. The exposure of people resident in or visiting rural areas could also have been grossly under-estimated. Material links between ED pesticide use and specific illnesses or deformities are complicated by the multifactorial nature of disease, which can be affected by factors such as diet. Despite these difficulties, a large body of evidence has accumulated linking specific conditions to ED pesticides in wildlife and humans. A more precautionary approach to the use of ED pesticides, especially for non-essential purposes is proposed.

The Chernobyl nuclear accident in 1986 not only caused serious ecological problems in both the Ukraine and Belarus, which continue to the present day, but also contaminated a large part of the higher latitudes of the northern hemisphere. In this paper an overview is given of the latter problems in upland UK, where ecological problems still remain some 17 years after initial contamination. Following deposition of radiocaesium and radioiodine in May 1986, measurements of radioactivity in grass and soil indicated a rapidly declining problem as the radioiodine decayed and the radiocaesium became immobilised by attachment to clay particles. However, these studies, as well as the advice received by the Ministry of Agriculture, Fisheries and Food, were based on lowland agricultural soils, with high clay and low organic matter contents. The behaviour of radiocaesium in upland UK turned out to be dominated by high and persistent levels of mobility and bioavailability. This resulted in the free passage of radiocaesium through the food chain and into sheep. Consequently the Ministry banned the sale and movement of sheep over large areas of upland Britain, with bans remaining on some farms to the present day. Present day predictions suggest that these bans will continue in some cases for some years to come. The causes of radiocaesium mobility in upland areas have subsequently been the subject of intense investigation centred around vegetation and, in particular, soil characteristics. Soil types were identified which were particularly vulnerable in this respect and, where these coincided with high levels of deposition, sheep bans tended to be imposed. While much of the earlier work suggested that a low clay content was the main reason for continuing mobility, a very high organic matter content is now also believed to play a major role, this being a characteristic of wet and acidic upland UK soils. The overall message from this affair is the importance of a fundamental understanding of biogeochemical pathways in different ecosystems when attempting to predict the impacts of large-scale contamination.