Addendum to Food Additives and Contaminants 2002, 19, 492-501 migration of monomers from liquid crystalline poly(p-hydroxybenzoic acid-co-2-hydroxy-6-naphthoic acid).

Liquid-crystalline co-polyesters (e.g. a random copolyester based on p-hydroxybenzoic acid (HBA) and 2-hydroxy-6-naphthoic acid (HNA) known as Vectra A950) offer good barrier properties, but for food-contact use they require overall and specific migration testing. For Vectra A950 films, the highest overall migration level obtained was 2.3 mg x dm(-2) (13.8 mg x kg(-1)) in olive oil (10 days at 40 degrees C), well below the EC limit of 10 mg dm(-2) (60 mg x kg(-1)). The highest specific migration of HBA was 15.2 microg x dm(-2) (91.2 microg x kg(-1)) in olive oil (2 h at 175 degrees C). In this case, the migration level was well below the EC limit of 10 mg dm(-2) (60 mg x kg(-1)). For HNA, the highest value obtained was 4.3 microg x dm(-2) (26 microg x kg(-1)) in 10% ethanol (4 h at 100 degrees C), well below the specific migration limit (SML = 50 microg x kg(-1)). The results obtained shows that even at these severe conditions, the migration values comply with the new European Union Directive 2002/72/EC, which regulates plastic materials and articles for food contact use. In addition, the polymer Vectra A950 complies with Food Contact Notification (FCN) No. 103 of the United States Food and Drug Administration (FDA). Vectra A950 is therefore permitted for food-contact use both in the European Union and the USA.

Migration of monomers from liquid crystalline poly(p-hydroxybenzoic acid-co-2-hydroxy-6-naphthoic acid).

Liquid-crystalline co-polyesters (e.g. a random copolyester based on p-hydroxybenzoic acid (HBA) and 2-hydroxy-6-naphthoic acid (HNA) known as Vectra A950) offer good barrier properties, but for food-contact use require overall and specific migration testing. For Vectra A950 films, the highest overall migration level obtained was 2.3 mg kg(-1) in olive oil (10 days at 40 degrees C) well below the EC limit of 60 mg kg(-1). The highest specific migration for p-hydroxybenzoic acid was 15.2 microg dm(-2) in olive oil (2h at 175 degrees C). For 2-hydroxy-6-naphthoic acid, the highest value obtained was 4.3 microg dm(-2) in 10% ethanol (4h at 100 degrees C), although it was not on the EC positive and cannot yet be used for food-contact materials. At conditions considered as severe, the estimated daily intake for p-hydroxybenzoic acid was calculated as 11.9 microg/person day(-1) and for 2-hydroxy-6-naphthoic acid it was 5.3 microg/person day(-1). The results exceed the threshold of regulation of 1.5 microg/person day(-1).

Measurement of endogenous tryptamine in rat brain by capillary column gas chromatography mass spectrometry.

A capillary column gas chromatographic mass spectrometric method, involving the use of a deuterated analogue as internal standard, was developed and used to identify and quantify tryptamine in the rat brain. The mean level of tryptamine in rat whole brain was 0.54 pmol g-1.