 BackResearch Article ScienceAsia 23 (1997): 171-184 |doi: 10.2306/scienceasia1513-1874.1997.23.171 TOTAL CONTENTS AND SEQUENTIAL EXTRACTIONS OF HEAVY METALS IN BANG PAKONG RIVER ESTUARINE SEDIMENTSVORAVIT CHEEVAPORN AND PICHARN SAWANGWONGABSTRACT: Samples of sediments collected along the Bang Pakong River were analysed for Cu, Pb, Zn, Crd, Cr and Ni contents by atomic absorption spectrometry. Determinations of redox potential, organic carbon, hydrogen sulfide, and grain size analysis were also performed. The sequential extraCtions revealed that high percentages of Cr, Ni, and Cu are associated/transported in the residual fraction, thus being practically impossible to release to the environment on the deteriorating scale. In contrast, Pb, Zn, and Cd were found mostly associated/transported in the leachable fractions which can be remobilized and released to the environment by various physical-chemical processes. Hence the selective distribution of. trace metals should be taken into account and caution must be exercised in evaluation of risk of potential release of these metals in the environment. Department of Aquatic Science, Burapha University, Chonburi 20131, Thailand. Received 7 February, 1997
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