Assessment of population exposure to tetrachloroethylene emissions from French dry-cleaning facilities and their associated health risks

Tetra chloroethylene is a solvent widely used in French dry-cleaning facilities. In 1995, the International Agency for Research on Cancer (IARC) classified it as probably carcinogenic to humans (group 2A). Chronic exposure through inhalation also has non-carcinogenic effects, mainly renal and neurological; toxic effects on reproduction have also been reported. Five exploratory tetrachloroethylene measurement campaigns were conducted to assess the health risk in the general population. These measurements took place in one dry-cleaning facility located in a shopping mall and in four dry-cleaners on the ground floor of residential buildings, all of them with different types of machines and ventilation systems. Concentrations ranged from 0.050 to 0.680 mg/m(3) in the shopping mall, from 8 to 53 mg/m(3) in the dry-cleaners in residential buildings and from 0.29 to 2.9 mg/m(3) in the flats immediately above them. These results show a reduction of tetra chloroethylene concentrations in some flats and thus the potential effect of the type of dry-cleaning machine and of ventilation on the tetra chloroethylene concentrations in indoor air. A worst-case health risk assessment based on the toxicological reference value for inhalation was conducted for the general population. The hazard quotients calculated for non-carcinogenic effects indicate that there is no reason for concern about the health of mall customers chronically exposed to it. The results in residential buildings suggest that people living immediately above ground-floor dry-cleaners may have health risks if the dry-cleaner uses a type-3 machine in a shop without mechanical ventilation. Individual excess risks, estimated with available unit risks, exceed the WHO benchmark of 10(-5) regardless of the machine technology or type of ventilation. The principal uncertainties of this study are related to: i) measurements; ii) lack of knowledge about variables influencing the atmospheric emissions, seasonal effects of dry-cleaning activity, and residents' lifestyle; iii) working assumptions about the duration of population exposure; iv) the toxicological reference values used which could be questioned following the publication of the Toxicological Review by the US EPA in 2008.