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

Ethylene glycol ethers, especially 2-ethoxyethanol and 2-butoxyethanol (BE) are frequently used in industry and household as solvents and detergents b ecause 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-m ass spectrometry. For determination of BAL and BE with head space-capillary gas chromatography, water and HCl or sodium dihydrogen phosphate were adde d to the sample. No further extraction or derivatization were necessary. Fo r BAA determination after adding HCl and sodium dihydrogen phosphate the sa mples were extracted with ethyl acetate and derivatized with 2,2,2-trichlor oethanol/HCl. The analytical methods presented here are reliable, sensitive and rapid. The new methods were developed for mammalian cell culture syste ms, because such in vitro systems are especially useful for metabolic studi es and have the advantage of choosing species and organ specificity. In the cell culture experiments presented here it was demonstrated that Opossum k idney cells are able to metabolize BAL to BAA within 24 h. After this inter val, in the cells neither BAL nor BAA were accumulated, whereas BAA was fou nd in the cell culture media.