Octanol/water partition coefficients of toxaphene congeners determined by the "slow-stirring" method

The octanol/water partition coefficients (K-ow) for a series of technical t oxaphene peaks and congeners (n = 36) and organochlorines pentachlorobenzen e (PC1Bz), hexachlorobenzene (HC1Bz), mirex and polychlorinated biphenyl co ngeners (CB) 105, 153 and 209) were determined using the "slow-stirring" te chnique with two different concentrations at 25 degrees C. K(ow)s of the or ganochlorines were consistent with published values and results from the tw o treatments were in good agreement, suggesting the toxaphene congener K(ow )s are accurate and precise. Log K-ow, of toxaphene components / congeners ranged from 4.77 +/- 0.076 to 6.64 +/- 0.074, and were significantly relate d to chlorine number (log Ko(ow) = 3.4 + [0.28 * # Cl], r(2) = 0.44, p < 0. 001). Additional variation in toxaphene congener K-ow, and likely other phy sical chemical properties, is due to chlorine position and the structure of the carbon skeleton. These results represent some of the first physical-ch emical properties of individual toxaphene congeners. (C) 1999 Elsevier Scie nce Ltd. All rights reserved.