The efficiency of remediation measures in once heavily polluted industrial areas is conventionally assessed by its decreasing pollution burden.

To what extent the redevelopment contributes to an improvement in health is important.

To have a valid physiological parameter or/and indicator of exposure as well as the methodology to measure both bio- and/or effect-monitoring is decisive. An epidemiologic cohort study was conducted, whereby kindergarten children from a heavily polluted industrial area and a control one were observed over a prolonged period of time under conditions of redevelopment.

The regionspecific external exposure was assessed by 27 volatile organic compounds.

The effect was assessed with a specially developed stable-isotope-based diagnostic test ([15N]methacetin test) measuring the liver’s detoxification capacity. The children’s internal load reflected the significant differences in exposure to chlorinated compounds.

The ratio of concentrations for the indicator components (chlorinated compounds) was 2.3 for exposed and control children. The pollution-exposed children showed a 6% lower liver detoxification capacity. A reduction in pollution by about 70% was reflected in an improved liver detoxification capacity.

The difference between polluted and control area was no longer significant. Prolonged exposure effects to low concentrations of xenobiotics can disturb hepatic functioning.

This stable-isotope-based test can be used as a tool to determine health effects of multi-component exposure when the predominant pollutant is taken into account.

The presented method appears well suited for bio-effect-monitoring for the purpose of screening and testing the efficaciousness of the remediation activities.