Considering human toxicity as an impact category in life cycle assessment

Characterization of toxic chemicals with relevance to human exposure does normally not belong to Life Cycle Assessments (LCA) and is still a topic of research. The concept of hazard potential classes proposed in this paper is primarily based on threshold limit values that are considered to be a measure of the severity of potential effects. In the absence of threshold limit values the R-phrases of the ordinance of dangerous substances are used. Substances are assigned to five hazard potential classes (A to E). Potentially dangerous chemicals are identified and substances of low toxicological relevance are excluded from further evaluation. The location where a probable exposure might occur (indoor versus outdoor) and inter-media transport of substances is considered. The product comparison is based both on the results of the proposed “semi-quantitative screening method” and on toxicological expert knowledge.