Phthalates in paper and board packaging and their migration into Tenax and sugar

Abstract

Packaging samples for many kinds of foodstuffs were received from manufacturers together with basic information about the materials used in their production. Half of the 29 samples studied contained phthalates in amounts exceeding 5mg/kg. Two types of paper bag intended for sugar had exceptionally high phthalate contents although they were flexo printed. The maximum contents of di-isobutylphthalate (DIBP) and dibutylphthalate (DBP) were 450 and 200 mg/kg, respectively. The phthalates found originated from adhesives used in the joints of the packaging. In other packagings manufactured at the same time, DIBP concentrations varied from 92 to 193mg/kg. Phthalates were also determined in sugar before and after packaging. Migration of phthalates ranged from 57 to 74% of the original content in the packaging after 4 months storage. Packed sugar contained DIBP 2.2-2.6mg/kg and DBP 0.5-1mg/kg. The sugar packagings were also tested using Tenax as a food stimulant. The results indicated that 69-91% of the original content of the phthalates migrated into Tenex after 10 days at 40°C. The major drawback with migration testing using Tenax is its high cost; it is not practical to fill the whole 1kg packaging with Tenax, and smaller samples of packaging must be used instead. However, the distribution of substances in the packaging might be nonuniform. In the sugar packagings studied here, the difference between phthalate concentrations in two samples taken from the same packaging was nearly 100-fold.