Water Quality
Standards
Summary information extracted from: Guidelines for drinking-water quality, 2nd ed. - Vol. 1. Recommendations. - Geneva, World Health Organization, 1993. pp. 70-71.
Di(2-ethylhexyl)adipate (DEHA) is used mainly as a plasticizer for synthetic resins such as polyvinyl chloride (PVC). As a consequence of its use in PVC films, food is the most important source of human exposure (up to 20 mg/day). Reports of the presence of DEHA in surface water and drinking-water are scarce, but DEHA has occasionally been identified in drinking-water at levels of a few micrograms per litre.
DEHA is of low short-term toxicity; however, dietary levels above 6000 mg/kg of feed induce peroxisomal proliferation in the liver of rodents. This effect is often associated with the development of liver tumours. DEHA induced liver carcinomas in female mice at very high doses but not in male mice or rats. It is not genotoxic. IARC has placed DEHA in Group 3.
Although DEHA is carcinogenic in mice, the toxicity profile and lack of mutagenicity of DEHA support the use of a TDI approach to setting a guideline value for DEHA in drinking-water. A TDI of 280 µg/kg of body weight was calculated by applying an uncertainty factor of 100 (for inter- and intraspecies variation) to the lowest NOAEL for DEHA of 28 mg/kg of body weight per day based on fetotoxicity in rats. The guideline value is 80 µg/litre (rounded figure) based on an allocation of 1% of the TDI to drinking-water.
