In a proof-of-principle study, scientists from Washington State University showed that a chemical mixture of different plastic-related compounds can cause health effects in rats, three generations after the actual chemical exposure occurred (Manikkam et al. 2013). The article published in the peer-reviewed scientific online journal PLOS1 demonstrated that chemical exposure during pregnancy could lead to changes in the testis, prostate, kidney, ovaries and fat storage of affected animals. In addition, in the third generation after the exposure occurred, animals had a higher incidence of obesity and other effects, including changes to the testis and ovarian disease. These effects are hypothesized to be caused by the chemical exposure to the pregnant great-grandmother, and passed on to subsequent generations by changes on the DNA, so called epigenetic effects.
The chemical mixture given to pregnant dams daily during day 8 until day 14 of gestation via injection into the stomach contained bisphenol A (BPA, 50 mg/kg bw), diethylhexylphthalate (DEHP, 750 mg/kg bw) and dibutylphthalate (DBP, 66 mg/kg bw). A second exposure group received the chemical mixture diluted to half of the concentration. All three substances are relevant for food contact materials.
The authors acknowledge that neither the exposure route, nor the doses represent realistic human exposure conditions. Doses are far higher than typically encountered by people. The study is therefore not designed to inform risk assessment for these specific compounds. Moreover, this study calls for further research on the mechanism of epigenetic alterations by every day chemicals during sensitive windows of development and the implications for human health.
Food Packaging Forum background information on epigenetics
Chemical defects “last generations”. BBC Health, 26 January 2013.
Manikkam, M., et al. (2013). “Plastics Derived Endocrine Disruptors (BPA, DEHP and DBP) Induce Epigenetic Transgenerational Inheritance of Obesity, Reproductive Disease and Sperm Epimutations.” PLoS ONE 8(1): e55387.