Arsenic speciation in Portuguese in situ lichen samples.

In this work, 29 lichen samples collected in situ and representative of high loadings, medium loadings and zero loadings for factors related to natural and anthropogenic emission sources, were analyzed to determine arsenic contents and its species extractability. The studied sites showed As values between 430 and 5590 microg kg(-1). The cationic forms were extracted at most of the sites varying between 0.5% and 6.6%. Extracted anionic forms were not detected in any of the sites. In a few other sites the % of extracted As(III)--more toxic--exceeds the equivalent value of As(V). It is concluded that arsenic in native Parmelia sulcata Taylor under the form of As(V) either was kept unchanged or was partially transformed into As(III) (more frequent) or partially transformed into As(III) and dimethylarsinic acid (DMAA) or partially transformed into DMAA.

Local and regional sources of air pollutants at Northern Lisbon area, Portugal.

Aerosol chemical composition data for PM(2.5) and PM(2.5-10), were acquired from 1999 to 2002 at a sub-urban area located at Northern Lisbon area. Monte Carlo target transformation factor analysis (MCTTFA) was used to identify the main sources of air particulate matter. Eight main groups of sources were identified: soil, sea, traffic, an industrial source related to coal combustion, cement production and incineration, metallurgic industry and Ba, Se and Cs sources.

Gravimetric and chemical features of airborne PM 10 AND PM 2.5 in mainland Portugal.

This paper describes concentration amounts of arsenic (As), particulate mercury (Hg), nickel (Ni) and lead (Pb) in PM(10) and PM(2.5), collected since 1993 by the Technological and Nuclear Institute (ITN) at different locations in mainland Portugal, featuring urban, industrial and rural environments, and a control as well. Most results were obtained in the vicinity of coal- and oil-fired power plants. Airborne mass concentrations were determined by gravimetry. As and Hg concentrations were obtained through instrumental neutron activation analysis (INAA), and Ni and Pb concentrations through proton-induced X-ray emission (PIXE). Comparison with the EU (European Union) and the US EPA (United States Environmental Protection Agency) directives for Ambient Air has been carried out, even though the sampling protocols herein--set within the framework of ITN's R&D projects and/or monitoring contracts--were not consistent with the former regulations. Taking this into account, 1) the EU daily limit for PM(10) was exceeded a few times in all sites except the control, even if the number of times was still inferior to the allowed one; 2) the EU annual mean for PM(10) was exceeded at one site; 3) the EPA daily limit for PM(2.5) was exceeded one time at three sites; 4) the EPA annual mean for PM(2.5) was exceeded at most sites; 5) the inner-Lisbon site approached or exceeded the legislated PMs; 6) Pb levels stayed far below the EU limit value; and 7) concentrations of As, Ni and Hg were also far less than the reference values adopted by EU. In every location, Ni appeared more concentrated in PM(2.5) than in coarser particles, and its levels were not that different from site to site, excluding the control. The highest As and Hg concentrations were found in the neighbourhood of the coal-fired, utility power plants. The results may be viewed as a "worst-case scenario" of atmospheric pollution, since they have been obtained in busy urban-industrial areas and/or near major power-generation and waste-incineration facilities.