Use of poly(ethylene terephthalate) plastic bottles for the sampling, transportation and storage of potable water prior to mercury determination

Abstract

Comparisons were carried out between the use of poly(ethylene terephthalate)(PET) plastic bottles and clear glass bottles for the storage of potable water samples for up to 10 days, prior to mercury determination. The PET bottles were found to be as suitable as glass bottles for the above purpose, while also offering significant cost saving and safety advantages. Two chemical preservatives were also compared. The recovery of mercury was significantly enhanced for both bottle types by the pre-addition of either hydrochloric acid or an acid dichromate preservative solution. The latter was preferred on safety grounds owing to its obvious colour. Long-term storage was not tested as this laboratory has a maximum five working day turnaround time for this determinand. The concentration range of interest was 0.05–1.5 µg l^–1 of mercury.