Migration of volatile substances from recycled high density polyethylene to milk products.

Plastic recycling is the main solution to reduce the plastic waste. High-density polyethylene has not been recycled
yet successfully as food contact material due to the amount of chemicals present in post-consumer material
together with its high chemical sorption capacity. The migration of two post-consumer recycled HDPE milk
bottles were studied to both 50 % ethanol as food simulant and real food (one type skimmed milk and two plant
base beverages (soy milk and horchata). Firstly, a headspace-solid phase extraction-gas chromatography mass
spectrometry method was developed and optimized to analyze these milky samples. After exposure, 53 compounds
were identified and among them several additives, NIAS such as 2,5-cyclohexadiene-1,4-dione, 2,6-bis
(1,1-dimethylethyl), 2,4-di-tert-butylphenol and 7,9-di-tert-butyl-1-oxaspiro(4,5)deca-6,9-diene-2,8-dione,
degradation products of antioxidant compounds as well as several residues from cleaning products, detergents
and flavoring agents were found. Finally, the risk assessment was applied and it was found that five compounds
did not comply after migration to 50 % ethanol.