Journal of the Brazilian Chemical Society
On-line version ISSN 1678-4790
CRUZ, Lícia P. S.; CAMPOS, Vânia P.; NOVAES, Jussival A. P. and TAVARES, Tania M.. Laboratory validation of a passive sampler for SO2 atmospheric monitoring. J. Braz. Chem. Soc. [online]. 2005, vol.16, n.1, pp. 50-57. ISSN 1678-4790. http://dx.doi.org/10.1590/S0103-50532005000100008.
The performance of a passive sampler was tested under exposure in Teflon chamber. The SO2 trapped in impregnated filter with 1.0 x 10-2 mol L-1 Na2CO3 solution was extracted in ultrasound bath with H2O2 solution for 15 min and determined as SO42- by ion chromatography. The sampler presented good performance except for air in total stillness condition (0 m s-1), for very short exposure periods (0.5 h), for atmosphere with O3 > 150 mg m-3 and for high concentrations of reduced sulfur compounds. The relative humidity of the air (20 - 80%) and the exposure to zero concentration did not affect the sampler performance. It showed stability for one month at 4 ºC or for one week at about 25 ºC. Its precision varied within 3.5 and 23% depending of the SO2 concentration and the accuracy varied from 91 to 100%.
Keywords : passive sampling; atmospheric sulfur dioxide; air monitoring.