Lin, Tsair-Fuh

2 items:

The organic contamination level based on the total soil mass is not a proper index of the soil contamination intensity Concentrations of organic contaminants in common productive soils based on the total soil mass give a misleading account of actual contamination effects. This is attributed to the fact that productive soils are essentially water-saturated, with the result that the soil uptake of organic compounds occurs principally by partition into the soil organic matter (SOM). This report illustrates that the soil contamination intensity of a compound is governed by the concentration in the SOM (Com) rather than by the concentration in whole soil (Cs). Supporting data consist of the measured levels and toxicities of many pesticides in soils of widely differing SOM contents and the related levels in in-situ crops that defy explanation... Categories: Publication; Types: Citation; Tags: Crop contamination, Organic contaminants, Pesticides
Partition Coefficients of Organic Contaminants with Carbohydrates In view of the current lack of reliable partition coefficients for organic compounds with carbohydrates (Kch), carefully measured values with cellulose and starch, the two major forms of carbohydrates, are provided for a wide range of compounds: short-chain chlorinated hydrocarbons, halogenated benzenes, alkyl benzenes, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, and organochlorine pesticides. To ensure the accuracy of the Kch data, solute concentrations in both water and carbohydrate phases are measured by direct solvent extraction of the samples. For a given compound, the observed partition coefficient with cellulose (Kcl) is virtually the same as that with starch (Kst). This finding expedites... Categories: Publication; Types: Citation

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