Grouping of phthalates for risk characterization of human exposures

The European Food Safety Authority (EFSA) has developed a group tolerable daily intake (TDI) for low molecular weight phthalates (LWP) including diisononyl phthalate (DINP). The LWP covered by the group TDI induce clear adverse effects on rat testicular development and pronounced reductions in fetal testicular testosterone. In contrast, DINP has a very low potency regarding changes in testicular testosterone in fetal rodents and does not induce adverse effects on reproductive endpoints. The most sensitive toxicity endpoint for DINP is liver toxicity. Due to the much lower potency of DINP for effects on testosterone, absence of reproductive toxicity, and its noted liver toxicity as compared to the LWP in the group, DINP should not be included in the group TDI.