Radionuclides in domestic and imported foods in the United States, 1983-1986.

Findings in the Food and Drug Administration's Radionuclides in Foods program are summarized for samples collected between October 1, 1982, and September 30, 1986. All radionuclide findings for Total Diet and reactor samples were either in Action Range I or low in Range II of the surveillance and control recommendations given by the Federal Radiation Council. The only long-range trend noted was a continuation of the general decline in dietary intake of 90Sr since 1961. Imported food samples were analyzed for contamination after the Chernobyl nuclear accident. The findings for imported foods indicate that the surveillance efforts successfully targeted contaminated foods, and that contamination levels were below levels of concern for all but one oregano and 3 cheese samples.

Application of an instrumental neutron activation analysis procedure to analysis of food.

The capabilities of a relatively simple instrumental neutron activation analysis procedure were demonstrated by performing multielement analyses of 240 Food and Drug Administration Total Diet Studies food composites. The analytical results provide a comprehensive database for a wide range of food types. The procedure incorporates only two irradiations and counts, polyethylene packaging and no sample transfer after irradiation. Concentrations were determined for 19 elements, 16 of which were found in most composites. Detection limits were calculated for all food groups and are given for the 22 elements included in the quantitative analysis scheme. In a qualitative search for 18 additional elements for which no standards were run, none were detected in any of the composites. Specific factors such as interferences from the blank are discussed in regard to their effects on the uncertainties associated with the experimental data and the detection limits. Modifications to the procedure are also suggested for lowering the detection limits for specific elements.

Alopecia induced in young mice by exposure to excess dietary zinc.

Second generation mice were exposed to normal (50 ppm, Group I) or excess (2000 ppm, Group II) zinc in the maternal diet during gestation and lactation, then weaned and continued on the mother's diet until sacrifice at 8 weeks. Tibia zinc reflected dietary intake. Group II had reduced plasma copper, body weight, and hematocrit; the second coat of hair appeared late and was lighter in color than Group I, possibly as an effect of copper and pigmentation development and hair growth.

Survey of radionuclides in foods, 1978-1982.

Samples from the U.S. Food and Drug Administration's total-diet, market-basket program, samples of imported foods, and samples collected near nuclear power plants were analyzed for radionuclides. Most radionuclides were below the limit of detection for a majority of the samples; however, data are reported for 3H, 90Sr and 137Cs in certain samples. Generally a downward trend is observed for 90Sr when data for the 5-yr period were compared. The total dietary intake of either 90Sr or 137Cs is well within Range I of the Federal Radiation Council (FRC) radiation protection guides for these radionuclides.