Effects of Cooking on Concentrations of Polychlorinated Dibenzo-p-dioxins and Related Compounds in Green Leafy Vegetable ‘Komatsuna’

• Published in: Food Hygiene and Safety Science (Shokuhin Eiseigaku Zasshi) Vol. 42; no. 5; pp. 339 - 342
• Main Authors: HORI, Tsuguhide, NAKAGAWA, Reiko, TOBIISHI, Kazuhiro, IIDA, Takao, TSUTSUMI, Tomoaki, SASAKI, Kumiko, TOYODA, Masatake
• Format: Journal Article
• Language: English
• Published: Japan Japanese Society for Food Hygiene and Safety 01.10.2001
• Subjects: Benzofurans - analysis; Cooking; Dibenzofurans, Polychlorinated; dioxin(s); Environmental Pollutants - analysis; Food Contamination - analysis; Japan; PCB; Polychlorinated Biphenyls - analysis; Polychlorinated Dibenzodioxins - analogs & derivatives; Polychlorinated Dibenzodioxins - analysis; vegetable; Vegetables - chemistry; Water
• ISSN: 0015-6426; 1882-1006
• DOI: 10.3358/shokueishi.42.339

The effects of ordinary household cooking processes on concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) (dioxins) were investigated in ‘komatsuna’, a green leafy vegetable popular in Japan. The concentrations of dioxins were compared using isomer-specific analyses of both uncooked and cooked edible parts of the plant. The mean total 2,3,7,8-chlorine substituted PCDD and PCDF concentrations were reduced from 46.53 pg/g and 0.714 pg/g to 8.301 pg/g and 0.210 pg/g by washing with tap water, and further reduced to 6.054 pg/g and 0.148 pg/g by subsequent boiling, respectively. The cooking processes markedly decreased the concentrations of PCDD/Fs, while having little effect on those of dioxin-like PCBs. The mean total concentration as 2,3,7,8-tetraCDD equivalents (TEQ) was reduced from 0.058 pgTEQ/g to 0.026 pgTEQ/g by washing with tap water and further reduced to 0.019 pgTEQ/g by subsequent boiling. These results suggest that ordinary cooking processes provide a means of reducing the level of dioxins in green leafy vegetables.