Page 300 - Materials Chemistry, Second Edition

284 4 Life Cycle Impact Assessment

transfer constants. 337) A list of a minimum of data required for an ecotoxicity model
is integrated into the OMNITOX method description 338) :
• Dissociation constants (acid/base)
• Reaction constant of second order for the reaction with OH in the gaseous phase
• Half-life of hydrolysis in water
• Henry constant or air/water distribution coefficient
• Fusion point
• Molar mass
• Octanol/water distribution coefficient
• Particle gas distribution coefficient (e.g. after Junge)
• Distribution coefficient (steady state) between water and sediment
• Distribution coefficient (steady state) between water and soil
• Vapour pressure
• Water solubility
• Acute lethal toxicity for fresh water fish
• Acute toxicity for invertebrates
• Alga growth inhibition as degradation of the growth rate
• Alga growth inhibition as reduction of the biomass
• Ready biodegradability by different end points
• Inherent biodegradability, biological degradability after adaptation of the degrad-
ing micro-organisms or their enzyme system to the substrate
Some, but not all of these data must be declared by the producer for assessment
of the potential risk of chemicals. This unsatisfactory situation applies even for
the most progressive chemical law of the world, REACH, 339) as work-around quan-
titative structure–activity-relationships (QSARs) are used to obtain an estimate of
the characteristics of substances with a minimum of information, often only a
structural formula. Even measured physico-chemical data often scatter within a
wide range. This was shown by the example of the well-known environmental
chemical dichloro-diphenyl-trichloroethane (DDT) and its transformation product
dichlorodiphenyldichloroethylene (DDE). 340) The only possible way-out is an evalu-
ation of the data available and a normative definition on which data should be used
for exposure calculations. A first step has been made in the model USEtox 341) already
discussed in Section 4.5.3.2.4 in the context of the human toxicity indicator. As an
ecotoxicological indicator in the USEtox model, so far only the aquatic ecotoxicity
has been worked out, presumably because a maximum of data are available in this
context, mostly for daphnia, fish and algae. So far, characterisation factors (fresh
water ecotoxicity) for about 2500 substances have been provided. 342) The factors

337) Hertwich, Pease and McKone (1998).
338) Guin´ ee et al. (2004); see also Kl¨ opffer (1996b, 2012b), Schwarzenbach, Gschwend and Imboden
(2002) and Kl¨ opffer and Wagner (2007a).
339) EC (2006) and Scheringer and Hungerb¨ uhler (2008); see also Kl¨ opffer (1996c, 2002, 2004).
340) Eganhouse and Pontolillo (2002).
341) Rosenbaum et al. (2008, 2011), Jørgensen and Hauschild (2011) and Hauschild, Jolliet and
Huijbregts (2011).
342) Rosenbaum et al. (2008) and Henderson et al. (2011).