Critical review of low-density polyethylene's partitioning and diffusion coefficients for trace organic contaminants and implications for its use as a passive sampler

Document Type


Date of Original Version



Polyethylene (PE)-water equilibrium partitioning constants, K PEw, were reviewed for trace hydrophobic organic contaminants (HOCs). Relative standard deviations were <30% for phenanthrene, anthracene, fluoranthene, and pyrene implying excellent reproducibility of K PEw across laboratories and PE sources. Averaged K PEw values of various HOCs were best correlated with aqueous solubility, logC wsat(L): logK PEw = -0.99(±0.029)logC wsat(L) + 2.39(±0.096) (r 2 = 0.92, SE = 0.35, n = 100). For 80% of analytes, this equation predicted logK PEw within a factor of 2. A first-order estimation of K PEw can be obtained assuming constant solubility of the compounds in the PE, such that the variation in C wsat(L) determines the differences in K PEw. For PE samplers, K PEw values do not change with the thickness of the PE sampler. The influence of temperature on K PEw seems dominated by solubility-changes of the compound in water, not in PE. The effect of salt is rather well understood, using a Schetschenow-style approach. The air-PE partitioning constant, K PEa, can be approximated as the ratio of K PEw/K aw (the air-water partitioning constant). A critical review of diffusivities in PE, D PE, suggests that best results are obtained when using the film-stacking method. A good correlation is then found between D PE and molar volume, V m (Ǻ 3/mol): logD PE (m 2/s) = 0.0145(±0.001)V m + 10.1(±0.20) (r 2 = 0.76, SE = 0.24, n = 74). © 2011 American Chemical Society.

Publication Title, e.g., Journal

Environmental Science and Technology