HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Walton, B. T. Articles by Francis, C.W. Search for Related Content PubMed Articles by Walton, B. T. Articles by Francis, C.W. Agricola Articles by Walton, B. T. Articles by Francis, C.W.

Soil Sorption of Volatile and Semivolatile Organic Compounds in a Mixture

Environmental Sciences Div., Oak Ridge Natl. Lab., Oak Ridge, TN 37831-6038;
Analytical Chemistry Div., Oak Ridge Natl. Lab., Oak Ridge, TN 37831-6038;
Engineering Physics and Mathematics Div., Oak Ridge Natl. Lab., Oak Ridge, TN 37831-6038;
Graduate Program in Environmental Toxicology, Univ. of Tennessee, Knoxville, TN 37901-1071.

^* Corresponding author.

ABSTRACT

Studies were conducted to evaluate lipophilicity as a predictor sorption for a mixture of organic compounds with high vapor pressures commonly present at hazardous waste sites. Sorption partition coefficients (K_p) for the mixture of 16 volatile and semivolatile organic compounds were measured on a Captina silt loam (Typic Fragiudult) and a McLaurin sandy loam (Typic Paleudults) using a zero headspace extractor. The experimental K_p was determined for acrylonitrile, furan, methyl ethyl ketone, tetrahydrofuran, benzene, toluene, p-xylene, chlorobenzene, chloroform, nitrobenzene, 1,2-dichlorobenzene, 1,2,3-trichloropropane, carbon tetrachloride, ethylene dibromide, 1,2,4,5-tetrachlorobenzene, and hexachlorobenzene on each of the two soils. The K_p values were generally lower in the McLaurin sandy loam, which had a lower organic C content (0.66 ± 0.04%) than the Captina silt loam (organic C content = 1.49 ± 0.06%). Sorption was normalized to soil organic C content of the soil by converting K_p for each compound and soil to K_oc. Weighted regression analyses of K_{oc observed} for the compounds in the mixture on K_{oc predicted} from the n-octanol/water partition coefficient (K_ow) for individual compounds yielded a pooled, weighted regression of K_{oc observed} = 1.084 + 0.457 K_{oc predicted}, n = 29, r = 0.88. Statistical analysis indicated that the slope of 0.457 ± 0.046 (estimated standard error) was significantly less than 1.00, indicating that soil sorption of nonionic organic compounds differed from that predicted for the same individual compounds based on K_ow. The results indicate that predictive equations for sorption of individual organic compounds can be applied to mixtures of volatile and semivolatile organic compounds in soils when log K_ow are in a range from approximately 1 to 3; however, outside this range a correction factor may be needed.

Pesticide Toxicology Lab., 115 Insectary Building, State Univ., Ames, IA 50011-3140

Publication no. 3835, Environmental Sciences Division, ORNL.

Received for publication October 28, 1991.