Abstract: The invention relates to a borehole treatment composition containing an aqueous phase and a non-aqueous oil phase, emulsifiers and, where appropriate, further customary additives, the non-aqueous oil phase containing at least one of a) paraffins having from 5 to 22 carbon atoms; and b) internal olefins having from 12 to 30 carbon atoms in the molecule; in the form of a blend with c) carboxylic esters of the formula R—COO—R?, where R stands for a linear or branched, saturated or unsaturated alkyl radical having from 15 to 25 carbon atoms and R? denotes a saturated, linear or branched alkyl radical having from 3 to 22 carbon atoms. The ratio of the toxicity of internal olefins of chain length C16/C18 (standard IO) to the toxicity of the constituents of the non-aqueous oil phase, in each case measured by the Leptocheirus plumulosus acute, static 96 hour/10 day sediment toxicity test (in accordance with ASTM E 1367-92 & EPA/600/R-94/025, Section 11), is less than 1.

Abstract: A drilling fluid containing an aqueous phase and an oil phase and an ether carboxylic acid of the formula: RO(CH2CH2O)x(CH2CHR1O)yCH2—COOX wherein, R is a saturated or unsaturated, branched or unbranched alkyl or alkenyl group containing 6 to 22 carbon atoms, x is a number from 1 to 20 and y is 0 or a number from 1 to 20, provided that the sum of x and y is at least 1 and at most 25, R1 is an alkyl group containing 1 to 4 carbon atoms and X comprises at least one member selected from the group consisting of a hydrogen atom, monovalent anions and polyvalent anions.

Abstract: A process for imparting lubricity to an aqueous drilling fluid used in geological exploration involving: (a) providing an aqueous drilling fluid; (b) providing a lubricant component containing a partial glyceride of predominantly unsaturated fatty acids having from about 16 to 24 carbon atoms; and (c) introducing the partial glyceride into the aqueous drilling fluid.