AUTOMATED TECHNIQUE FOR MERCURY DETERMINATION AT SUBNANOGRAM PER LITER LEVELS IN NATURAL-WATERS

A sensitive and automatic technique for dissolved mercury determination has been developed id order to produce rapid and accurate dissolved mercury determinations in natural waters at ambient levels. This is needed for building realistic mass balance budgets and providing more accurate data in monitoring programmes for this metal. The detection limit obtained with a 45 ml sample was 0.1 ng l(-1). The precision of the method-over the range 0.5-50 ng l(-1) was found to be approximately 5%. Eight samples per hour can be analysed without carryover effects. The instrumentation is very robust but strict control measures are required to ensure a mercury-free environment around the instrumentation.