The results of the European LCI (Stalmans et al., 1995) are
summarized in Table 1. The data show that no technical or scientific
basis exists to support a general environmental superiority
claim, either for an individual surfactant or for various
options for sourcing from petrochemical, oleochemical, or
agricultural feedstocks and minerals. Therefore, environmental
acceptability is not associated with raw material source, at
least in the LCI context.
Most of the issues on environmental acceptability focus on
the effects on the environment associated with the use and
disposal of these surfactants. These effects are taken into account
by a risk assessment. The first step in a risk assessment
is an estimate of the concentrations of surfactants in the environmental
compartments of interest, such as wastewater
treatment plant effluents, surface waters, sediments, and soils
(Mulligan, 2005; Lehmler, 2005). This estimate is generated
either by actual measurement or by prediction via modeling.
The measured or predicted concentrations are then compared
to the concentrations of surfactant known to be toxic to
organisms living in these environmental compartments. If
the measured or predicted concentration is less than the notoxic-effect
level, then a margin of safety exists. Just to be
sure, a safety factor of 10, 100, or 1000 is often applied. That
is, the margin of safety between the actual, measured and noeffect
concentrations should differ by one, two, or three orders
of magnitude.