RESUMO
The ability of Chlorella vulgaris to accumulate heavy metals in solution (Mn, Cr, Ni, Zn and Cu) was investigated. Various parameters (algal biomass, pH and contact time of the algae with the sample) have been studied. Nine mg of algal biomass, pH 8 and 15 min of contact time, with 1 ppm of each metal, were the optimized conditions. At pH 8, the optimum value to rise the maximum binding, a fraction of metals in solution precipitates forming hydroxides. Combining both processes, a chemical-biological system for the removing of metals at ppb levels from the environment is obtained. The simultaneous determination of these five metals was performed by capillary electrophoresis (CE) with a UV/Vis detector.
RESUMO
This paper presents a study concerning the degree of pollution due to arsenic and selenium in atmospheric particulates of La Coruña (NW Spain). Sampling of particulate matter was accomplished with high volume samplers equipped with glass microfibre filters; samples were collected in two different areas (one an industrial area and the other a rural area). For As and Se determination, hydride generation and electrothermal atomization atomic absorption spectrometry, respectively, were used.