[Survey on the quality of commercial Nigari (crude magnesium chloride [sea water])].
Contents of minerals (Mg, Ca, Na and K), anions (SO4(2-), Br- and Cl) and heavy metals (Pb, Cd, Zn, Hg and As) were determined in 17 commercial samples of Nigari, 15 samples of crude magnesium chloride (sea water) products as a food additive and 2 magnesium-containing foods. Obtained values were compared with the specifications proposed in a draft of the eighth edition of Japan's Specifications and Standards for Food Additives. Out of 15 food additive samples, only 5 samples satisfied the specification. Since the Joint FAO/WHO Expert Committee on Food Additives (JECFA) proposed to lower the limits of heavy metals in food additives, a simple method was developed for the determination of low levels of Pb and Cd by extracting chelates of these metals with organic solvents. The quantification limits for Pb and Cd were 0.5 microg/g and 0.05 microg/g, respectively. It was estimated from the SO4(2-)/Ca ratios that 15 samples were sea water evaporation products, and the remaining 2 were ion-exchange membrane process products. No pollution with heavy metals was found in any of the samples.
Ogimoto
Mami
M
Tokyo Metropolitan Institute of Public Health: 3-24-1, Hyakunin-cho, Shinjuku-ku, Tokyo 169-0073, Japan.
Uematsu
Yoko
Y
Kabashima
Junichiro
J
Suzuki
Kumi
K
Ito
Koichi
K
D005503:Food Additives / Q000032:analysis*; D005504:Food Analysis; D015636:Magnesium Chloride / Q000032:analysis*; D019216:Metals, Heavy / Q000032:analysis; D012623:Seawater / Q000032:analysis*; D013054:Spectrophotometry, Atomic; D014874:Water Pollutants, Chemical / Q000032:analysis
D005503:Food Additives; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D015636:Magnesium Chloride