The study was carried out by the Ministry of Agriculture, Fisheries and Food (MAFF). It follows earlier investigations by HM Inspectorate of Pollution (HMIP) which confirmed that a hazardous waste incinerator at the Coalite plant released high levels of dioxins to air and water, and by the National Rivers Authority, which found high levels of dioxins in a river downstream of the plant (ENDS Reports 202, pp 16-20, and 203, pp 4-5). The incinerator is now being upgraded.
These investigations were launched after tests by MAFF revealed that milk from two dairy farms near the works contained elevated levels of dioxins. Cattle on a third farm were subsequently found to be contaminated as well. Sales of the contaminated produce have been banned.
The new study underscores the need for the curbs on beef sales from animals on the third farm, which is about half a mile from the chemical works. Dioxin levels in the liver fat of animals from this farm ranged between 720-1,312ng/kg, expressed as the toxic equivalent (TEQ) of the most toxic of the dioxins, 2,3,7,8-TCDD. The highest level found on the other two farms was 93ng/kg. For beef muscle fat, the figures were 72-317 and 22ng/kg, respectively.
According to MAFF, the results for the third farm are "extremely elevated." Consumption of most combinations of beef and beef offal from this herd would result in the official tolerable daily intake of dioxins being exceeded to a "significant extent."
Most soil samples taken at all three farms were found to contain dioxins above UK rural background levels of up to 10.3ng/kg, expressed as a TEQ. The highest concentration found was 54ng/kg. In general, the highest dioxin levels occurred in the top five centimetres of soil, suggesting that they were caused by relatively recent deposition.
No results are yet available from a MAFF programme of herbage analysis, or from an HMIP survey of dioxins in soils on other farms in the locality. These will be published in due course, ensuring that the Coalite dioxin saga will run and run for some time yet. The company is now negotiating to buy the three farms.