title: Measurement of cosmogenic 35S activity in rainwater and lake water.
abstract: Although cosmogenic 35S (t(1/2) = 87 d) has been found to be a unique and excellent radioactive tracer for stable S in atmospheric and aqueous environments, its application has been very limited because an analytical method for its detection has not been well-documented. Here, we report a rapid and robust method for analyzing extremely low levels of 35S in rainwater and lake water samples. About 20-L water samples were preconcentrated using an anion exchange column. The purified 35S was precipitated as BaSO4, and the precipitates were collected using a GF/B filter. The 35S in precipitates on the filter was directly counted using a super-low-background liquid scintillation counter with cocktail. We successfully measured 35S in precipitation and lake water samples using this method, which promises future diverse applications of the 35S tracer to S cycling in the environment and to age determination of lake water and shallow groundwater.
authors.affiliation: School of Earth & Environmental Sciences/RIO, Seoul National University, Seoul 151-742, Korea.
authors.forename: Young-Lim
authors.initials: YL
authors.lastname: Hong
authors.forename: Guebuem
authors.initials: G
authors.lastname: Kim