Transfer of bisphenol A from thermal printer paper to the skin

Of 13 thermal printing papers analyzed, 11 contained 8–17 g/kg bisphenol A (BPA). When taking hold of a receipt consisting of thermal printing paper for 5 s, roughly 1 μg BPA (0.2–6 μg) was transferred to the forefinger and the middle finger if the skin was rather dry and about ten times more if these fingers were wet or very greasy. This amount transferred to dry skin was neither significantly increased when taking hold of the paper at up to 10 sites, nor reduced when BPA-free paper was contacted afterwards. After 60–90 min, BPA applied to the skin as a solution in ethanol was only partially or no longer at all extractable with ethanol, whereas BPA transferred to the skin by holding thermal printer paper remained largely extractable after 2 h. This suggests that penetration of the skin depends on the conditions. Extractability experiments did not enable us to conclude whether BPA passes through the skin, but indicated that it can enter the skin to such a depth that it can no longer be washed off. If this BPA ends up in the human metabolism, exposure of a person repeatedly touching thermal printer paper for 10 h/day, such as at a cash register, could reach 71 μg/day, which is 42 times less than the present tolerable daily intake (TDI). However, if more than just the finger pads contact the BPA-containing paper or a hand cream enhances permeability of the skin, this margin might be smaller.     

Injector-internal thermal desorption from edible oils. Part 2: chromatographic optimization for the analysis of migrants from food packaging material

Injector-internal thermal desorption from edible oil or fat is a convenient sample preparation technique for the analysis of solutes in lipids or extracts from fatty foods. The injector temperature is selected to vaporize the solutes of interest while minimizing evaporation of the bulk material of the oil. This technique has been in routine use for pesticides for some time. Now its potential is explored for migrants from food contact materials, such as packaging, into simulant D (olive oil) or fatty/oily food, which means extending the range of application towards less volatile compounds. The performance for high boiling components was investigated for diisodecyl phthalate (DIDP) and diundecyl phthalate (DUP). Since the injector temperature needs to be as high as 260degreesC, some bulk material of the oil enters the column and must be removed after every analysis. This is achieved by a coated precolumn backflushed towards the end of each analysis. Desorption of the solutes is particularly efficient in the initial phase, when a thin sample film is spread on the liner wall, and is largely determined by the diffusion speed in the oil after the latter has contracted to droplets. An increased carrier gas flow rate during the splitless period supports the transfer into the column. It is concluded that the technique is attractive for migrant analysis, with DUP being at the upper limit of the boiling point.     

Enantiomere und diastereomere 2-Methoxymethyl-pyrrolidin-1-dithiocarbonsäureester

Summary Formation of the 2-methoxymethyl-pyrrolidine-1-dithiocarboxylates2–4 and alkylation of2 and3 were studied. Enantiomeric and diastereomeric derivatives of4, the preparation of diastereomeric mixtures of4 by alkylation of3 in the presence of strong bases, and formation of6 by phase transfer alkylation of2 are described. The two enantiomers of 2-(4-bromophenyl)-2-oxo-ethyl 2-methoxymethylpyrrolidine-1-dithiocarboxylate2 have been characterized by X-ray analysis.

Verstorben am 22. Juni 1996