A margin of exposure approach to assessment of non-cancerous risk of diethyl phthalate based on human exposure from bottled water consumption

Phthalates may be present in food due to their widespread presence as environmental contaminants or due to migration from food contact materials. Exposure to phthalates is considered to be potentially harmful to human health as well. Therefore, determining the main source of exposure is an important issue. So, the purpose of this study was (1) to measure the release of diethyl phthalate (DEP) in bottled water consumed in common storage conditions specially low temperature and freezing conditions; (2) to evaluate the intake of DEP from polyethylene terephthalate (PET) bottled water and health risk assessment; and (3) to assess the contribution of the bottled water to the DEP intake against the tolerable daily intake (TDI) values. DEP migration was investigated in six brands of PET-bottled water under different storage conditions room temperature, refrigerator temperature, freezing conditions (40 °C ,0 °C and −18 °C) and outdoor] at various time intervals by magnetic solid extraction (MSPE) using gas chromatography–mass spectroscopy (GC-MS). Eventually, a health risk assessment was conducted and the margin of exposure (MOE) was calculated. The results indicate that contact time with packaging and storage temperatures caused DEP to be released into water from PET bottles. But, when comprising the DEP concentration with initial level, the results demonstrated that the release of phthalates were not substantial in all storage conditions especially at low temperatures (<25 °C) and freezing conditions. The daily intake of DEP from bottled water was much lower than the reference value. However, the lowest MOE was estimated for high water consumers (preschooler > children > lactating women > teenagers > adults > pregnant women), but in all target groups, the MOE was much higher than 1000, thus, low risk is implied. Consequently, PET-bottled water is not a major source of human exposure to DEP and from this perspective is safe for consumption.