Passive sampling (Chemcatcher) is applied for monitoring several heavy metals (Cd, Cu, Zn and Ni) in Nhue river (Vietnam). The study is conducted in two (2) parts. (1) The experiment was investigated sampling rate (Rs, Lh-1) of Chemcatcher defined as the equivalent volume of water extracted per unit time which is affected by temperature and turbulence suitable for Vietnam condition, temperature (25 and 35oC) and stirring speed (40 and 60 rpm) were performed in controlled-flow conditions. Results of the sampling rate (Rs) were 0.0092-0.0179 Lh-1, 0.0042-0.0268 Lh-1, 0.0063-0.0231 Lh-1 and 0.0067-0.0205 Lh-1 for Cd, Cu, Zn and Ni, respectively. (2) Two locations on Nhue river was conducted in parallel with spot water sampling in 24 and 72 hours field deployment. Chemcatcher sampling results are showed time-weighted average (TWA) water concentration, 0.023-0.045 µg/L in two sampling points for Cadmium and 16.95-62.17 µg/L, 9.74-35.71 µg/L for sampling point NM1, NM2 of Zinc, respectively.
Keyword
Passive sampling, heavy metals monitoring, Chemcatcher monitoring
