Fluxes of radiocaesium in selected rural study sites in Russia and Ukraine

Food production and food harvesting systems common in the areas contaminate d by the Chernobyl accident in Russia and Ukraine can be grouped into three major categories: collective farm produce, private farming produce and foo ds collected from natural ecosystems. The contribution of each of these sou rces to radiocaesium intake by people living in rural settlements in the mi d 1990s has been estimated at two major study sites, one in each country. T he collective farm system provided the smallest contribution (7-14%) to the intake of radiocaesium at both sites. Natural food was the major contribut or to intake at the Russian site (83%). Whereas private farm produce was th e major contributor (68%) at the Ukrainian study site. The difference betwe en the two sites was mainly because private milk production was stopped at the Russian site due to the contamination in 1986. A retrospective assessme nt of the situation 1 year after the accident shows that collective farming could have been a minor contributor to radiocaesium intake (8%), whilst pr ivate farming would have been the major contributor wherever private milk p roduction and consumption continued. The extent to which inhabitants consum e natural foods from forests has a considerable effect on their radiocaesiu m intake. The comparative importance of food products from natural ecosyste ms increases with time due to the long effective ecological half-lives of r adiocaesium in unimproved pastures and forests. Estimation of the fluxes of radiocaesium from the different production and harvesting systems showed t hat the contribution from private farming and food harvesting from natural ecosystems may be significant, contributing 14-30% to the total fluxes of r adiocaesium from an area even if the quantity of food produced in these sys tems is small. However, the major contributor to the flux exported from an area was the collective farming system, accounting for about 70-86% of the total. (C) 1999 Elsevier Science B.V. All rights reserved.