Phthalates (PAEs) are widely used as additives in plastics; as plasticizers or as solvents to hold color and scent.

Zhongze Gu and colleagues, Southeast University, China, have investigated the levels of eight PAEs present in cooking oil and mineral water packaged in plastic containers. By using HPLC-UV combined with solid-phase extraction, the team has shown that cooking oil consistently has a higher content of PAEs from packaging than mineral water, and that the amount of migration depends on the lipophilic character of the food matrix.

Migration occurred more readily at higher temperature, with longer contact time, and at higher dynamic frequency. After two months at 20 °C, cooking oil was seen to contain over 60 ng/mL of di-n-butyl PAE. At 70 °C, the concentration was almost twice that value.

• Analysis of Phthalate Migration from Plastic Containers to Packaged Cooking Oil and Mineral Water
  Q. Xu, X. Yin, M. Wang, H. Wang, N. Zhang, Y. Shen, S. Xu, L. Zhang, Z. Gu,
  J. Agric. Food Chem. 2010, 58 (21), 11311–11317.
  DOI: 10.1021/jf102821h