Determination of lead, naphthalene, phenanthrene, anthracene and pyrene in street dust

Street dust is a potential source of lead exposure to humans, however scarce information about the pollution levels with lead and polyromatic hydrocarbons exists in Venezuela, limiting the appropriate evaluation of the levels of risk of the people. This work was aimed in the determination of the concentrations of lead, naphtalene, anthracene, phenanthrene and pyrene in the street dust of the most transited avenues and streets of Maracay city. Thirty street dust samples were collected at the streets and avenues, troll and bus main station. Lead was determined by atomic absorption spectrometry after acid digestion [Pb-total], also the fractions of lead soluble in 1 M MgCI2 and 0.5 M ammonium acetate [pH = 7] were quantified. The polyaromatic hydrocarbons concentrations were determined by capillary gas chromatography equipped with a flame ionization detector. The Pb-total ranged between 734 and 11.439 micro g/g with the higher values at the most transited streets and avenues. About 60% of samples exhibited concentrations between 1.000 and 2.500 micro g/g, similar to the values reported in the literature for soils of urban areas. The fraction of lead soluble in magnesium accounted for less than 3% of Pb-Total, while the 0.5 M ammonium acetate solution represented more than the 75% of the total loads of the pollutant. The most contaminated samples were those taken at the toll with concentrations of 695.5 and 252.1 micro g/g phenanthrene and anthracene were the most abundant, while at the bus station all compounds were detected

Estudio de la concentración de arsénico, mercurio, plomo y fenantreno en la macha (Mesodesma donacium): implicancias alimentarias y toxicológicas / Study on arsenic, mercury, lead and phenanthrene concentration in surf clam (Mesodesma donacium): food and toxicological implications

The coastal environment around the Maipo river outlet in the proximity of San Antonio bay (5th Region, Chile) it is one of the most contaminated zone of the country due to discharges of industrial wastes on the river that affect the marine environment. The surf clam (Mesodesma donacium, Lamarck 1818) a benthic organism that provides an important source of seafood for human consumption is caught in this area. The total arsenic and mercury, lead and phenanthrene concentrations in the soft body of the surf clam were measured. Their concentration in the marine organism fluctuated between 1,23-1,33 µg/g As , 0,26-0,39 µg/g Hg, and 0,23-0,33 µg/g Pb (dry basis). Phenanthrene was not detected in the samples. In spite of the high concentration of the elements detected in the surf clam, only in the case of Hg their intake could imply a certain grade of risk for human health, especially for young humans. Chronic effects, such as personality changes, neurological damage and others, could exhibit in the medium term. Therefore, it is important to carry out regular food surveillance studies, especially oriented to the specie specific aspect of toxic elements and monitoring of polyaromatic hydrocarbons (PAH) in several marine food.

La zona costera de la bahía de San Antonio en las proximidades a la desembocadura del río Maipo (Quinta Región, Chile), es una de las áreas más contaminadas del país, debido a residuos industriales vertidos al río, los cuales afectan el ambiente marino. La macha (Mesodesma donacium, Lamarck 1818), organismo bentónico que constituye una importante fuente de alimento humano, es capturada en esta área. Se midió la concentración de arsénico total, mercurio total, plomo y fenantreno en el cuerpo blando de la macha, con el fin de determinar su ingesta y el riesgo toxicológico para el consumidor. Las concentraciones de los elementos en el organismo marino, fluctuaron entre 1,23_1,33 µg As g-1, 0,26_0,39 µg Hg g-1 y 0,23_0,33 µg Pb g-1, valores expresados en base seca. El fenantreno no fue detectado en las muestras. A pesar de las altas concentraciones de los elementos detectadas en la macha, sólo para el caso del Hg su ingesta puede significar un cierto grado de riesgo para la salud humana, especialmente en el consumidor joven. Efectos crónicos tales como cambios en la personalidad, daño neurológico y otros, pudieran manifestarse a mediano plazo. Por lo tanto, es importante realizar estudios regulares de vigilancia alimentaria, especialmente dirigidos a la especiación de los elementos tóxicos y el monitoreo de hidrocarburos poliaromático (HPA), en variados alimentos marinos.