Vertical and horizontal variability of volatile organic compounds in homes in Eastern Germany.

A German study on Indoor Factors and Genetics in Asthma (INGA) will be conducted for 10 years in towns of Eastern and Western Germany. The study will include an indoor and outdoor exposure assessment of BTEX (BTEX=benzene, toluene, ethyl benzene, ortho-xylene, and meta- plus para-xylene) volatile organic compounds (VOCs). In a pilot study, which was conducted in Erfurt, a city in Eastern Germany, during the winter of 1994, vertical and horizontal variabilities of BTEX concentrations within the homes were examined in detail. Passive sampling was conducted in the living room (at 0.7, 1.2, and 2.0 m height), bedroom (2 m), kitchen (2 m), and outside the window of the living room, in 20 homes of randomly chosen adults. The 20 houses consisted often old concrete constructions ('Altneubauten'=OLD, constructed between 1960 and 1970) and ten new concrete constructions ('Neubauten'=NEW, constructed between 1970 and 1980). At each apartment, Organic Vapour Monitor (OVM) 3500 passive sampling devices (3M Company) were exposed for 7 days. After elution with carbon disulfide (CS2), the samples were analyzed with dual column gas chromatography (GC) with flame ionization detector (FID). No significant differences between the median values of the weekly average air concentrations of the BTEX VOCs in the different heights of measurement in the living rooms could be detected. Kitchen and living room median BTEX concentrations were equal and both significantly higher than the bedroom concentrations (except benzene). The indoor BTEX air concentrations were significantly higher than the outdoor concentrations (except benzene). Significant differences in BTEX indoor concentrations between OLD and NEW buildings could not be detected (except toluene).