Franca Durante de Maio

Avaliação dos níveis de chumbo e cádmio em leite em decorrência de contaminação ambiental na região do Vale do Paraíba, Sudeste do Brasil

INTRODUCAO: Localizada em Cacapava, SP, Brasil, industria produtora de lingotes de chumbo provocou contaminacao ambiental na regiao do Vale do Paraiba, com chumbo e cadmio. Com o objetivo de avaliar o grau de contaminacao do leite produzido na regiao, devido a possivel ingestao, pelo gado, de gramineas e aguas contaminadas, foram determinados os teores de chumbo e cadmio no leite. MATERIAL E METODO: Foram analisadas 218 amostras de leite in natura e pasteurizado. O cadmio e o chumbo foram determinados por espectrofotometria de absorcao atomica com chama. RESULTADOS E CONCLUSOES: Das amostras analisadas, 43 apresentaram teores de chumbo acima do limite maximo estabelecido pela legislacao brasileira que e 0,05 mg/kg. O valor da mediana encontrada para o chumbo foi 0,04 mg/L. Os niveis de cadmio em todas as amostras foram menores que o limite de quantificacao do metodo que e 0,02 mg/L. Apesar da contaminacao ambiental, os niveis encontrados para o cadmio no leite estao abaixo do limite estabelecido pela legislacao brasileira que e 1,0 mg/kg.

Arsenic exposure assessment of children living in a lead mining area in Southeastern Brazil

Environmental contamination by arsenic compounds in the Ribeira River Valley, São Paulo, Brazil has already been observed. Lead mining and refining activities had been carried on since late colonial times and finished recently, at the end of 1995. The source of As in the region is known to be mainly from arsenopirite geological presence in the lead ore. Chronic exposure to arsenic compounds may cause peripheral vascular disorders, hyperpigmentation, hiperkeratosis and cancer of the skin, bladder, lung, liver and other internal organs. The purpose of this study was to assess children exposure to arsenic from environmental sources in the region. Urine samples from children between 7 to 14 years old were collected at the following localities: Cerro Azul (Paraná); urban areas of Ribeira (São Paulo) and Adrianópolis (Paraná); Vila Mota neighborhood (rural area of Adrianópolis) and Serra neighborhood (Iporanga, São Paulo), identified as groups 1, 2, 3 and 4, respectively. Group 1 was considered as non-exposed control group. Toxicologically relevant forms of As were determined by atomic absorption spectrometry with hydride generation system. The median values of urine arsenic levels obtained in groups 1, 2, 3 and 4 were respectively: 3.60, 6.30, 6.41 e 8.94 microg/L.

A rapid method for mercury determination in urine of workers exposed to mercury vapor

ABSTRACT It is shown that the urine from workers exposed to mercury vapor contains practically only inorganic mercury (II), which can be easily determined by flow injection cold vapor atomic absorption spectrometry after adding only HNO3 to the urine at room temperature. If organic mercury is suspected to be present, the sample is treated with KMnO4/H2SO4 at 80°C - 100°C and total mercury is determined. On using HNO3 only, 30 - 40 urine samples/h can be easily processed. The method presents good accuracy, precision and high sensitivity, achieving a limit of detection and a limit of quantification (L.O.Q), respectively, of 0.12 mg/L and 0.4 mg/L Hg (II) in the final dilution, using 1.0 mL urine. Urine reference SRM - NIST as well as samples from workers exposed to mercury vapor were analyzed by the proposed methodology.

Determinação de mercúrio em águas sanitárias comercializadas em região do sudeste do Brasil

In order to determine the mercury content present as a contaminant in samples of bleach used in water and food disinfection, a method for sample treatment using chloridric acid to eliminate the chlorine was proposed. The technique of cold vapour atomic absorption spectrophotometry, used to quantify the mercury, showed a recovery of 103%. Sixty nine samples of bleach were analysed and the values found for the median and 90th percentil were respectively, 15 and 67 mg/L. According to the values of residual mercury found and using the quantities of bleach recommended by the Brazilian Sanitary Authorities, the use of these disinfectants offers no risk to human health.In order to determine the mercury content present as a contaminant in samples of bleach used in water and food disinfection, a method for sample treatment using chloridric acid to eliminate the chlorine was proposed. The technique of cold vapour atomic absorption spectrophotometry, used to quantify the mercury, showed a recovery of 103%. Sixty nine samples of bleach were analysed and the values found for the median and 90th percentil were respectively, 15 and 67 mg/L. According to the values of residual mercury found and using the quantities of bleach recommended by the Brazilian Sanitary Authorities, the use of these disinfectants offers no risk to human health.In order to determine the mercury content present as a contaminant in samples of bleach used in water and food disinfection, a method for sample treatment using chloridric acid to eliminate the chlorine was proposed. The technique of cold vapour atomic absorption spectrophotometry, used to quantify the mercury, showed a recovery of 103%. Sixty nine samples of bleach were analysed and the values found for the median and 90th percentil were respectively, 15 and 67 micrograms/L. According to the values of residual mercury found and using the quantities of bleach recommended by the Brazilian Sanitary Authorities, the use of these disinfectants offers no risk to human health.