[Toxicological assessment. A solid basis for preventive health care? Considerations on the preventive character of guidelines for (heavy) metal contamination of children's playgrounds].

The present report discusses the standard limit reference values for metal content of playgrounds, set by the authorities in North-Rhine-Westphalia, Berlin, Hamburg and Bremen. Taking the metals arsenic, lead and cadmium as an example, the causative role of region specific conditions for establishing the limit values for protective measures are described. Essentially, two factors influence the decision: 1. the background concentrations of metals in sand and soils differ between the various states; 2. there is a lack of a uniform concept for the quantitative evaluation of oral intake as a main route of ingestion of metals endangering the health of children on child playgrounds. Due to insufficient data, arbitrary assumptions in respect of intake, relevant age group or playing-time on playgrounds are made. From a toxicological point of view the standard limit values, exceed the span of toxicological tolerance, in an attempt to combine pragmatic and toxicological considerations. However, only few of these values agree with the basic principles of preventive care.