Gas chromatographic methods for determination of gamma-BHC in technical emulsifiable concentrates and water-dispersible powder formulations and in lindane shampoo and lotion: collaborative study.
Although the gas chromatographic separation of the isomers of BHC was demonstrated two decades ago, the present AOAC method of analysis of BHC for gamma-isomer (lindane) content is based on a separation carried out on a liquid chromatographic partition column. A method of analysis has been developed that uses an OV-210 column for separation of the gamma-isomer from the other isomers and impurities in technical BHC. Di-n-propyl phthalate was chosen as an internal standard. The same system allows quantitation of lindane in lotion and shampoo after these products are extracted with ethyl acetate-isooctane (1 + 4). The analytical methods were subjected to a collaborative trial with 10 laboratories. The coefficient of variation for technical BHC was 2.83%. For the water-dispersible powder and emulsifiable concentrate, the coefficients of variation were 2.89% and 4.62%, respectively. Coefficients of variation for 1% lindane lotion and shampoo were 4.36% and 11.92%, respectively. The method has been adopted official first action.
D002849:Chromatography, Gas / Q000379:methods; D004655:Emulsions; D006203:Hair Preparations / Q000032:analysis; D001556:Hexachlorocyclohexane / Q000032:analysis*; D007536:Isomerism; D011208:Powders; D012915:Soaps / Q000032:analysis*; D013501:Surface-Active Agents / Q000032:analysis*; D013535:Suspensions
D004655:Emulsions; D006203:Hair Preparations; D011208:Powders; D012915:Soaps; D013501:Surface-Active Agents; D013535:Suspensions; D001556:Hexachlorocyclohexane