Susumu Ishimitsu
Kyoto Pharmaceutical University
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Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment | 2001
Yukari Tsumura; Susumu Ishimitsu; Akiko Kaihara; Kimihiko Yoshii; Yumiko Nakamura; Yasuhide Tonogai
Plasticizer contamination of foods sold in retail packed lunches and set lunches in restaurants was determined by GC/MS. The phthalate esters were as follows: diethyl, dipropyl, dibutyl, dipentyl, dihexyl, butylbenzyl, dicyclohexyl, di(2-ethylhexyl), dioctyl, diisooctyl (mixture of isomers) and diisononyl (mixture). Di(2- ethylhexyl) adipate was also determined. Sixteen packed lunches and ten set lunches were analysed, and in all samples the concentration of di(2-ethylhexyl) phthalate (DEHP) was the highest, at 0.80–11.8 mg/ kg in packed lunches and 0.012–0.30 mg/kg in set lunches. The DEHP content of five packed lunches exceeded 1.85 mg, which is the EU tolerable daily intake (TDI) for a person of 50 kg body weight. Foodstuffs that were components of the packed lunches were taken from the factory at each step of preparation and phthalates were determined. For example, chicken contained 0.08 mg/kg DEHP when uncooked, 13.1 mg/ kg after frying and 16.9 mg/kg after packing. Disposable PVC gloves used in the preparation of foods were apparently the source of high DEHP concentrations. The gloves used during cooking or packaging were sprayed with 68% (w/w) ethanol to sterilize them. PVC gloves from the factory contained 22 or 41% by weight of DEHP. To confirm the link with the contamination problem, samples of boiled rice, croquette and boiled dry radish were handled in the laboratory with PVC gloves containing 30% (w/w) DEHP. DEHP migration levels of 0.05 mg/kg in rice or 0.33 mg/kg in croquette, and 11.1 mg/kg in radish were found. The alcohol sprayed onto the gloves increased the migration of DEHP to 2.03 mg/kg in rice, 2.45 mg/ kg in croquette, and 18.4 mg/kg in radish.
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment | 2001
Yukari Tsumura; Susumu Ishimitsu; Isao Saito; Hiroshi Sakai; Yukari Kobayashi; Yasuhide Tonogai
Plasticizers in duplicate diet samples obtained over 1 week were analysed in order to estimate daily intake. The phthalate esters were as follows: diethyl, dipropyl, dibutyl, dipentyl, dihexyl, butylbenzyl, dicyclohexyl, di(2-ethylhexyl), dioctyl, diisooctyl (mixture of isomers) and diisononyl (mixture). Di(2-ethylhexyl) adipate was also determined. Homogenized samples of composite meals were extracted with acetonitrile, lipids were removed by extraction into n-hexane and the acetonitrile layer was cleaned using FlorisilR and Bondesil PSAR dual layer column. Phthalates were determined by GC/MS (SIM). Phthalate recovery from the fortified food mixture by this method was 62.5–140.8%. Quality assurance as assessed by three laboratories indicated coefficient of variance in the levels of detected phthalates in same lot samples as below 10%. Detection limits were 0.1–23ng/g for each phthalate. One-week duplicate diet samples provided by three hospitals in three remote prefectures of Japan were analysed as individual meals. In all 63 samples, DEHP was present at the highest level among all phthalates in the range 10–4400ng/g. The intake of plasticizers estimated from all samples was 519 μg DEHP/day, 86 μg DEHA/day, 65 μg DINP/day, and 4.7 μg BBP/day. Calculated DEHP in 2-day samples out of 21 days exceeded EU TDI for a person of 50kg body weight (1850 μg per day). Disposable PVC gloves used during the preparation of meals were suspected as the source of the high DEHP content. One-day intake of the other phthalates and DEHA was below 7% of TDI in all cases. High concentrations of DEHP (5990ng/g) was found in baby food used in quality assurance work. The source of contamination was the PVC-tube used during production and was effectively reduced by replacing the tube by one made of stainless steel.
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment | 2003
Yukari Tsumura; Susumu Ishimitsu; Isao Saito; Hiroshi Sakai; Y. Tsuchida; Yasuhide Tonogai
Duplicate hospital diet samples obtained over 1 week in 2001 were analysed to estimate the daily intake of plasticizers and the results were compared with those obtained in 1999. The plasticizers quantified in this study were: dibutyl phthalate, butylbenzyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), di(2-ethylhexyl) adipate (DEHA), diisononyl adipate (DINA) and O-acetyl tributyl citrate (ATBC). Dipropyl, dipentyl, dihexyl and dicyclohexyl phthalate were also analysed but not detected. The analytical procedure for this follow-up study was essentially the same as in the previous one. Detection limits were 0.1–15.6 ng g-1 for each plasticizer. One-week duplicate diet samples provided by three hospitals in three remote prefectures of Japan were analysed as individual meals. DEHP was detected at 6–675 ng g-1 in 62 of 63 meals, significantly lower levels compared with those detected in 1999. Levels of DEHA and DINP also decreased. The mean intake of plasticizers estimated from all samples was 160 μg DEHP day-1, 12.5 μg DEHA day-1, 4.7 μg DINP day-1 and 3.4 μg BBP day-1. Levels of DINA were relatively high in meals from one hospital: in those meals, the average daily intake was 1338 μg day-1. Those of ATBC were also higher in meals from another hospital: the average daily intake was 1228 μg day-1. The sources of DINA and ATBC can be cling-film or sausage packaging.
Journal of The Food Hygienic Society of Japan (shokuhin Eiseigaku Zasshi) | 2001
Yukari Tsumura; Susumu Ishimitsu; Yumiko Nakamura; Kimihiko Yoshii; Akiko Kaihara; Yasuhide Tonogai
Ten samples of retail packed lunches purchased from convenience stores were determined for 11 phthalates and di(2-ethylhexyl) adipate (DEHA) in August 2000, 2 months after the prohibition of DEHP-containing PVC gloves in Japan. Each homogenized sample was extracted with acetonitrile, partitioned with n-hexane, and cleaned up using Florisil and PSA columns. Phthalates in the extract were determined by GC/MS (SIM). The limits of detection were 14.9 ng/g for di(2-ethylhexyl) phthalate (DEHP) and 18.6 ng/g for dibutyl phthalate (DBP). Levels of phthalates in packed lunch samples were 45 to 517 ng DEHP/g (198 ng/g, average), ND to 90 ng DEHA/g, and ND to 10.0 ng BBP/g. Diisononyl phthalate (DINP) was detected in one sample at 76 ng/g. Average DEHP level in ten samples was 4% of that in 1999. The contents of other phthalates were also reduced. DBP was not detected in any sample. Recovery of deuterated isomers added as surrogates was 27.9% for DNP-d4, and 40.6 to 101.5% for the other phthalates.
Journal of Health Science | 2002
Yukari Tsumura; Susumu Ishimitsu; Akiko Kaihara; Kimihiko Yoshii; Yasuhide Tonogai
Journal of Health Science | 2000
Yumiko Nakamura; Susumu Ishimitsu; Yasuhide Tonogai
Journal of Health Science | 2001
Yumiko Nakamura; Akiko Kaihara; Kimihiko Yoshii; Yukari Tsumura; Susumu Ishimitsu; Yasuhide Tonogai
Journal of Health Science | 2002
Akiko Kaihara; Kimihiko Yoshii; Yukari Tsumura; Susumu Ishimitsu; Yasuhide Tonogai
Chemical & Pharmaceutical Bulletin | 1990
Susumu Ishimitsu; Sadaki Fujimoto; Akira Ohara
Journal of Health Science | 2001
Yumiko Nakamura; Akiko Kaihara; Kimihiko Yoshii; Yukari Tsumura; Susumu Ishimitsu; Yasuhide Tonogai