Screening Environmental Samples

Instrument contamination is a continuing problem for laboratories analyzing environmental samples. Many environmental samples have complex matrices that require extensive cleanup to remove background contaminants embedded with the target analytes. Without considerable cleanup, which is time-consuming and costly, laboratories risk contaminanting analytical instruments and potentially closing down an instrument for hours or days--reducing productivity. This paper describes initial results in using UV-Visible spectroscopy to identify environmental samples that are likely to cause problems during analysis. This fast (45 seconds per sample), non-interfering technology successfully identified harmful levels of hydrocarbon in samples even when gas chromatograph results showed no significant hydrocarbon present. Moreover, UV-Vis reliably predicted surrogate recovery problems for reasons other than hydrocarbon contamination. Similarly successful results were achieved for samples containing PCBs. UV-Vis is not a universal screening tool, but may be valuable for screening samples with a hydrocarbon matrix.