Assessment of toxicological risks for life cycle assessment and eco-efficiency analysis

Abstract

Intention, Goal, Scope, Background

BASF has developed the tool of eco-efficiency analysis [1] to address not only environmental issues, but also issues posed by the marketplace, politics, product strategy and research. It is based on assessing environmental behaviour, environmental impact, possible effects on human health and ecosystems, and the costs of products and processes from the cradle to the grave. The goal of eco-efficiency analysis is to quantify the sustainability of products and processes.

Objectives

Many LCAs do not conduct an assessment of the toxicity potential. But, to arrive at a comprehensive assessment of products and processes, it is specifically this criterion which constitutes an important factor with regard to the evaluation of sustainability.

Methods

A comprehensive and easy-to-use model was developed to assess toxicity for eco-efficiency analysis. Our model uses the classifications for hazardous materials under EU law (31 R-phrases to describe different health effects). Moreover, eco-efficiency analysis requires an actual score of toxicity. This means that the following question has to be answered for every toxic effect, “How severe is a certain adverse effect compared to others?” This is a very personal judgement. We performed a survey with 40 toxicologists (industry and academia) and asked for a ranking and scoring of the toxic effects of 26 substances according to the personal opinion on how severe the toxic effects actually are considered to be. Based on the results, we developed a scoring system.

Results and Discussion

The system summarises different health effects in six groups, each with a score between 0 and 1000; combinations of various effects and different exposure routes are also taken into account. A substance is attributed to a group by its R-phrases. The new toxicity assessment model has been used in eco-efficiency analysis and has stood the test for one year. However, the hazard has to be combined with exposure to describe the actual risk. A second model was developed to describe the exposure using general use-categories and physico-chemical properties of the individual substances. The assessment of toxic effects has been a neglected in many LCAs.

Conclusions

The new models allow the assessment of toxic effects in an appropriate and easy way. The significant impact of thorough toxicity assessments on the outcome of eco-efficiency analysis is demonstrated by a comparison of different assessment models.

Recommendations and Oudook

LCA in combination with the evaluation of toxicity and risk-potentials will become more and more important in the future. This new methodology allows the calculation of toxicity potentials in a short time with a short set of input information. Those data as a part of the eco-efficiency analysis of BASF are useful to show the most important impacts over the whole life cycle. Decision-making processes with the eco-efficiency analysis will become much more useful by using this new assessment of toxicity factors.