Abstract
Selective determination of methylmercury and inorganic mercury in various samples by steam distillation and flameless atomic absorption method was established. This method is based on the following facts : (1) Alkylmercury chlorides are distilled by steam distillation in hydrogen chloride solution added with sodium chloride, while inorganic mercury remains in the distillation flask. (2) In sodium hydroxide solution containing a cupric ion, both methylmercury and inorganic mercury compounds (in this case, distillate contains only methylmercury compound) are reduced by tin (II), while in sulfuric acid solution, only inorganic mercury compound is reduced by tin (II). (3) The atomic mercury generated by mercury compounds absorbs the mercury resonance line at 253.7 nm. This method eliminated the most serious troubles in the determination of methylmercury such as the formation of a emulsion at benzene extractin, particulary in biological samples. The recovery rates of methylmercury and inorganic mercury contained in blood and placenta are 90-95% and 100-105%, respectively. This method was found to be applicable to various materials such as blood, animal organs, fish, and water and solid of river or lake bed.
