Priority assessment of toxic substances in life cycle assessment. Part II: assessing parameter uncertainty and human variability in the calculation of toxicity potentials.
Toxicity potentials are standard values used in life cycle assessment (LCA) to enable a comparison of toxic impacts between substances. This paper presents the results of an uncertainty assessment of toxicity potentials that were calculated with the global nested multi-media fate, exposure and effects model USES-LCA. The variance in toxicity potentials resulting from input parameter uncertainties and human variability was quantified by means of Monte Carlo analysis with Latin Hypercube sampling (LHS). For Atrazine, 2,3,7,8-TCDD and Lead, variation, expressed by the ratio of the 97.5%-ile and the 2.5%-ile, ranges from about 1.5 to 6 orders of magnitude. The major part of this variation originates from a limited set of substance-specific input parameters, i.e. parameters that describe transport mechanisms, substance degradation, indirect exposure routes and no-effect concentrations. Considerable correlations were found between the toxicity potentials of one substance, in particular within one impact category. The uncertainties and correlations reported in the present study may have a significant impact on the outcome of LCA case studies.
Huijbregts
M A
MA
Interfaculty Department of Environmental Science, Faculty of Environmental Science, University of Amsterdam, The Netherlands. m.huijbregts@frw.uva.nl
Thissen
U
U
Jager
T
T
van de Meent
D
D
Ragas
A M
AM
D004781:Environmental Exposure; D006801:Humans; D008962:Models, Theoretical; D009010:Monte Carlo Method; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D018675:Toxicity Tests; D015262:Xenobiotics / Q000493:pharmacokinetics / Q000633:toxicity*
D015262:Xenobiotics