New methods for determination of 2-butoxyethanol, butoxyacetaldehyde and butoxyacetic acid in aqueous systems, with special reference to cell culture conditions

Ethylene glycol ethers, especially 2-ethoxyethanol and 2-butoxyethanol (BE) are frequently used in industry and household as solvents and detergents because of their excellent hydrophilic and lipophilic properties. BE and its oxidation products, butoxyacetaldehyde (BAL) and butoxyacetic acid (BAA), are mainly associated with haemolytic toxicity. No method to determine BAL in aqueous systems (e.g. urine or blood) has been published up to now. BAL was synthesized by dehydration of BE and identified by gas chromatography-mass spectrometry. For determination of BAL and BE with head space-capillary gas chromatography, water and HCl or sodium dihydrogen phosphate were added to the sample. No further extraction or derivatization were necessary. For BAA determination after adding HCl and sodium dihydrogen phosphate the samples were extracted with ethyl acetate and derivatized with 2,2,2-trichloroethanol/HCl. The analytical methods presented here are reliable, sensitive and rapid. The new methods were developed for mammalian cell culture systems, because such in vitro systems are especially useful for metabolic studies and have the advantage of choosing species and organ specificity. In the cell culture experiments presented here it was demonstrated that Opossum kidney cells are able to metabolize BAL to BAA within 24 h. After this interval, in the cells neither BAL nor BAA were accumulated, whereas BAA was found in the cell culture media. Received: 10 August 1999 / Accepted: 21 December 1999