RESUMO
Concentrations of Al, Cd, Cr, Cu, Mn, Ni, Pb, U and Zn were determined in vegetables (leafy vegetables, fruit, root, grain and cereal), derived products (sugar, coffee, manioc flour, wheat flour, corn flour, and pasta) and animal products (meat, fish, milk) most frequently consumed by adult inhabitants of Rio de Janeiro city. A total of 90 samples were analyzed using inductively coupled plasma mass spectrometry (ICPMS) as the principal method following sample dissolution by dry and wet ashing. Generally, highest contributions for the intake of micronutrients (Cu, Mn, Ni and Zn) arise from bean, rice and wheat flour consumption. Meat, cow milk and the flours, wheat and manioc, are major sources of Al, Cd, Pb and U intake. The daily intake of nine elements via foodstuffs was estimated as: 3.4x10(-4) mg of U, 1.8x10(-3) mg of Cd, 2.8x10(-2) mg of Pb, 2.3x10(-2) mg of Cr, 8.9x10(-2) mg of Ni, 1.12 mg of Cu, 2.5 mg of Mn, 3.5 mg of Al and 4.8 mg of Zn. The intake of toxic elements ranged between 2.7% (Cd) and 30% (U) of the provisional tolerable daily intake and reference dose values indicating that food consumption is, at present, no critical factor for the uptake of these toxic metals, in the population studied here. Concerning micronutrients, the recommended values of daily intake of Cu and Mn are conveniently supplied by the diet; however, for Cr and Zn they are lower than the recommend daily allowance. Due to high metal concentrations and consumption rates, black bean is the foodstuff that provided the highest ingestion rates of Cu, Mn, Ni and Zn (36-60% of the reference dose), being therefore a very important source of micronutrient supply.
Assuntos
Dieta , Monitoramento Ambiental/estatística & dados numéricos , Análise de Alimentos/estatística & dados numéricos , Oligoelementos/análise , Adulto , Brasil , Cidades , Humanos , Espectrometria de Massas , Política NutricionalRESUMO
The concentrations of the naturally occurring radionuclides 232Th, 238U, 210Pb, 226Ra and 238Ra were determined in the vegetables (leafy vegetables, fruit, root, bean and rice) and derived products (sugar, coffee, manioc flour, wheat flour, corn flour and pasta) consumed most by the adult inhabitants of Rio de Janeiro City. A total of 88 samples from 26 different vegetables and derived products were analyzed. The highest contribution to radionuclide intake arises from bean, wheat flour, manioc flour, carrot, rice, tomato and potato consumption. The estimated daily intakes due to the consumption of vegetables and derived products are 1.9 mBq of 232Th (0.47 microg), 2.0 mBq of 238U (0.17 microg), 19 mBq of 236Ra, 26 mBq of 210Pb and 47 mBq of 228Ra. The estimated annual effective dose due to the ingestion of vegetables and their derived products with the long-lived natural radionuclides is 14.5 microSv. Taking into account literature data for water and milk from Rio de Janeiro the dose value increases to 29 microSv, with vegetables and derived products responsible for 50% of the dose and water for 48%. 210Pb (62%) and 228Ra (24%) were found to be the main sources for internal irradiation.