Isolation and identification of some unknown substances in disposable nitrile-butadiene rubber gloves used for food handling.
In Japan, disposable gloves made from nitrile-butadiene rubber (NBR) are frequently used in contact with foods. In a previous paper, we investigated substances migrating from various gloves made of polyvinyl chloride, polyethylene, natural rubber and NBR. Zinc di-n-butyldithiocarbamate (ZDBC), diethyldithiocarbamate (ZDEC) used as vulcanization accelerators, di(2-ethylhexyl)phthalate (DEHP) used as a plasticizer and many unknown compounds that migrated from NBR gloves into n-heptane were detected by GC/MS. In this paper, six unknown compounds were obtained from one kind of NBR glove by n-hexane extraction and each was isolated by silica gel chromatography. From the results of NMR and mass spectral analysis of the six unknown compounds, their structures are proposed as 1,4-dione-2,5-bis(1,1-dimethylpropyl)cyclohexadiene (1), 2-(1,1-dimethylethyl)-4-(1,1,3,3-tetra methylbutyl)phenol (2), 2,6-bis(1,1-dimethylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (3), 2,4-bis(1,1,3,3-tetramethylbutyl)phenol (4), 2-(1,1-dimethylethyl)4,6-bis(1,1,3,3-tetramethylbutyl)phenol (5) and 2,4,6-tris(1,1,3,3-tetramethylbutyl)phenol (6). Compound 1 was observed in five of the seven kinds of NBR gloves, and compounds 2-4 and 6, which are not listed in Chemical Abstract (CA), were present in four kinds of gloves.
Mutsuga
M
M
Division of Food Additives, National Institute of Health Sciences, Kamiyoga 1-18-1, Setagaya, Tokyo 158-8501, Japan. mutsuga@nihs.go.jp
Wakui
C
C
Kawamura
Y
Y
Maitani
T
T
D004209:Disposable Equipment; D020724:Elastomers; D005511:Food Handling / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D017575:Gloves, Protective; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009930:Organic Chemicals / Q000302:isolation & purification*; D012408:Rubber / Q000737:chemistry*
D020724:Elastomers; D009930:Organic Chemicals; C086285:nitrile butyl rubber; D012408:Rubber