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A single microwave digestion procedure was developed for use with a variety of seafood products. Inductively coupled plasma atomic emission and mass spectrometry were used to determine the levels of As, Cd and Pb in samples of tuna, salmon, shrimp, walleye, clams, oysters and lobster. The precision for ten replicate analyses of clams was 2.1% for As at the 10.0 pg g-1 level, 5.6% for Pb at the 0.067 pg g-1 level and 2.5% for Cd at the 0.079 pg g-1 level. Acceptable spike recoveries in each of the sample types were achieved using both detection methods. Results for two standard reference materials were in good agreement with certified values

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Early in 1986, the US Food and Drug Administration was faced with an epidemic of suspected product tampering complaints concerning glass found in jars of baby food. A fast, relatively inexpensive method was developed for characterising both the glass of the jars and the glass fragments found in the baby food. After dissolution in HF and HN03, the elemental composition of milligram to sub-milligram sized glass fragments was determined by inductively coupled plasma atomic emission spectrometry. Use of an HF-resistant nebuliser and torch allowed direct introduction of the sample solution. Comparison of the trace element content often allowed the discrimination of glass fragments when measurement of the refractive index proved inconclusive. Compilation of a preliminary database for the elemental composition of baby-food containers manufactured in the USA resulted from the investigation of numerous individual com pla i nts. Keywords: Elemental glass analysis; h ydrofluoric acid resistant inductively coupled plasma torch; product tampering* The inclusion of brand names and mention of commercial manufacturers are for information only and does not imply endorsement by the US FDA.

Standardized purified diets limited to required nutrients are needed for nutritional and toxicological studies. In the present study, we formulated a biotin- and cellulose-free diet of reproducible mineral composition (diet A), based on diet AIN-76, and fed it to weanling Long-Evans rats for 3 wk. Inductively coupled argon plasma atomic emission spectrometry was used to determine Ca, Cu, Fe, K, Mg, Mn, Na, P and Zn in liver, duodenum, kidney, spleen and femur. Results were compared with those obtained with rats fed biotin- and/or cellulose-supplemented variations of diet A, diet AIN-76 and diet NIH-31 (an open-formula stock diet). Weanling rats grew slowly and steadily on purified diet A. Growth rates increased when diet A was supplemented with biotin and cellulose. In general, differences among tissue mineral levels in rats fed diet NIH-31 and those fed diet AIN-76 were more pronounced than those among groups fed our purified diets. Values for hemoglobin and hematocrit were significantly lower in rats fed all purified diets than in those fed diet NIH-31. Diets A + biotin, A + cellulose and A + cellulose + biotin appear satisfactory as reference diets for measuring mineral interactions at near-requirement levels as well as effects of fiber on mineral utilization or for studies on vitamins whose endogenous synthesis may be influenced by dietary fiber.