Effect of NaCl on antimony and phthalate compounds leached from PET bottles

Abstract

Nowadays polyethylene terephthalate (PET) bottles are commonly used as food containers as they are lightweight. PET bottles contain antimony (Sb) and phthalate compounds. In contact with food, antimony and phthalate molecules could migrate from the inner surface of a PET bottle to the food. Therefore, we studied the effect of NaCl concentration in PET bottles on the leakage of antimony and phthalates. It was found that the concentration of antimony leached into the solution was about 6 ngl−1 after 5 days storage at room temperature in the absence of NaCl. Increasing NaCl concentrations to 6% caused a decrease in the amount of soluble antimony in the solution to 2 ngl−1 under the same conditions. In addition, the maximum leakage of phthalate compounds of about 130 ngl−1 occurred after 35 days of storage at 60 °C in 0.1% NaCl. It was found that the leakage of phthalate compounds decreased at higher NaCl concentrations (NaCl 0.5%–30%). Higher NaCl concentrations led to a decrease in the migration of antimony and phthalate compounds into the solution. This might be due to the fact that antimony and phthalate compounds form complexes with NaCl. However, the leakage of these compounds was lower than the standard guidelines of the United States Environmental Protection Agency for drinking water.

Occurrence of phthalates in different food matrices: A systematic review of the main sources of contamination and potential risks

“…Moreover, food with high acidity, that is, low pH, had higher concentrations of PAEs. Additionally, food contamination by PAEs can occur during steps of food production, like in tubes or conveyor belts (Carlos et al., 2018; Cirillo et al., 2013; Fang et al., 2017; Leechart et al., 2015; X. Wang, Song, et al., 2020).…”

“…It was proposed that NaCl could generate OCl − , a reactive Cl compound. However, aqueous solution with higher NaCl concentrations, around 5.0%–30%, had lower PAEs, probably because of the salting‐out effect, characterized by molecules solubility reduction and, therefore, a decreased migration (Leechart et al., 2015).…”

“…It is important to emphasize that of the 31 articles, only 13 investigated food packaging (Cacho et al., 2012; Carlos et al., 2018; Cirillo et al., 2013; de Jager et al., 2019; Fang et al., 2017; Fierens, Servaes, et al., 2012, 2013; Guazzotti et al., 2014; Leechart et al., 2015; Petersen & Jensen, 2010; Qian et al., 2018; Van Holderbeke et al., 2014; Y. Wang, Wen, et al., 2020). Nevertheless, seven of the 31 articles investigated the migration of PAEs from packaging to food in some tests.…”

Effect of Strain Levels on the Corrosion Resistance of an Enamel-Coated Steel Rebar

“…A round hole was drilled in the bottom of the plastic container and the steel rebar passed through the hole, then epoxy resin was applied to seal the gap between the steel rebar and the plastic container. Although a small amount (~6 ng/L) of antimony (Sb) would migrate from the PET to the solution [29], its effect on the corrosion reaction of steel is insignificant. Moreover, it is easier to drill a hole in the bottom of a plastic container and fix it with the steel rebar compared to the glass container.…”