Riskbedömning och naturligt producerade dioxiner
The highly toxic man-made substance referred to as dioxin (polychlorinated dibenzo-para-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs)) causes severe health damages both to humans and other organisms, with lethality as its worst. Because of the toxicity several risk assessments has been performed on dioxins trying to determine at what concentration there are no risk of exposure. Resent years of research has discovered that these substances are not only anthropogenically but also producedin natural processes, like volcanoes and forest fires. To investigate if there is a need to take these naturally formed dioxins into account in the risk assessment processes, interviews with persons at relevant institutions in Sweden has been made. Analyses of existing risk assessment methods and political documents were also made to complete the picture. The general attitude seams to be awareness of the natural contribution, but clueless when it comes to adapting it to the risk assessments. When scenarios of different possibilities of natural background levels were compared to available risk assessments there could be concluded that the natural contribution is of importance and should be pronounced as a special part of the risk assessment process.