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(W/MF197) A rapid, cheap and non-contaminant technique to quantify total arsenic in terrestrial plants and seafood animals from ecosystems affected by the Aznalcollar accident. FONT, RAFAEL1, DEL RIO, MERCEDES1, VELEZ, DIMORAZ2, ALMELA, INMACULADA2, ALGORA, SERGIO2, MONTORO, ROSA2, DE HARO, ANTONIO1, 1 2 ABSTRACT- On April, 1998 the failure of the mine tailings dam at Aznalcollar (Seville, Spain) caused a release of pyritic slurries containing large quantities of arsenic and other trace elements, affecting terrestrial and coastal ecosystems. Since then, hundreds of analyses have been performed by Atomic Absorption Spectrometry (AAS) to determine total arsenic in the living organisms from the polluted area. The time consuming and high cost of the analyses are handicaps to analyze a large number of samples. In this contribution we use Near Infra-Red Spectroscopy (NIRS) as a rapid, cheaper and non-contaminant alternative to the traditional methods of reference chemical analysis, to quantify total arsenic in plant and animal species. To conduct this study, samples were scanned by using a NIR spectrophotometer (NIRSystems model 6500, Foss-NIRSystems, Inc., Silver Spring, MD, USA).Calibration equations were performed from the spectral data and their arsenic reference chemical values, and then, validated on an external group of samples not included in the calibration set. The Standard Errors of Performance (SEP) and Coefficients of Determination (r2) shown by animal and plant species equations used to conduct this study were, respectively, 1.62 mgKg-1, d.w. and 0.84; 4.99 mgKg-1, d.w., and 0.64. These results show that NIRS can be used to determine total arsenic in animal and plant tissues, with accuracy enough for screening purposes. Key words: NIRS, arsenic, plants, animals |
