Thin-film solid-phase extraction to measure fugacities of organic chemicals with low volatility in biological samples

To investigate the environmental fate, food chain bioaccumulation, and toxicity of organic chemicals, it is often preferable to measure the chemical's fugacity rather than its concentration. However, simple methods to do this are rare. This paper presents a novel yet simple method to measure fugacities of a range of poorly volatile hydrophobic organic chemicals ranging in octanol-air partition coefficients from 10(5.6) to 10(9.2). Thin films of ethylene vinyl acetate coated on glass surfaces are used as solid-phase samplers of contaminated biological tissues. The technique is applied to fish tissue samples and spiked fish diets to determine method feasibility, equilibration times, reproducibility, and property characteristics of the thin films. It is concluded that the method provides an attractive technique to measure chemical fugacities in biological tissues without requiring solvent extractions and cleanup. The method is further expected to be applicable to investigate the fugacity of semivolatile and poorly volatile organic chemicals in air, water, sediments, and soil.