Environmental Health - Toxic Substances
U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting Charleston South Carolina March 8-12, 1999--Volume 1 of 3--Contamination From Hard-Rock Mining, Water-Resources Investigations Report 99-4018A
Development of a Passive Integrative Sampler for Labile Metals in Water
By William G. Brumbaugh, Jimmie D. Petty, James N. Huckins, and Stanley E. Manahan
A Stabilized Liquid Membrane Device (SLMD) is described for potential use as an in-situ passive integrative sampler for Cd, Cu, Ni, Pb, and Zn in natural waters. The SLMD (patent pending) consists of a 15 cm long strip of low-density polyethylene (LDPE) layflat tubing containing 1 mL of an equal mixture (v/v) of oleic acid (cis-9-octadecenoic acid) and Kelex-100® (7-[4-ethyl-1-methyloctyl]-8-quinolinol]). The reagent mixture diffuses in a controlled manner to the exterior surface of the LDPE membrane, which results in a relatively constant sequestration rate of several divalent metals for at least four weeks. Concentration factors of several thousand can be realized after just a few days allowing for extraction and quantitation of extremely low elvels of these metals by common spectroscopic methods. Data is presented for field deployment of SLMDs at two sites impacted by hard rock mining. Effects of pH and flow-rate on the SLMD sampling rate is discussed.