Chonthicha Atthabordee. Accumulation and distribution of some heavy metals in water, sediment and aquatic animals in the canal system of Ratchaburi and Samut Songkhram provinces . Master's Degree(Technology of Environmental Management). Mahidol University. : Mahidol University, 2006.
Accumulation and distribution of some heavy metals in water, sediment and aquatic animals in the canal system of Ratchaburi and Samut Songkhram provinces
Abstract:
Environmental pollution is a world-wide problem and heavy metals are
belonging the most important pollutants. Intense activity in the industrial and
agricultural sectors has inevitably increased the levels of heavy metals in nature. For
these reasons, it is essential to determine and compare the concentrations of heavy
metals (Cd, Cu, Fe, Pb and Zn) in (fish and mollusk) and to examine the correlation of
heavy metals between those in the Rang Thap Tab canal, from June 2004 to April
2005, being an important canal of the Mae Khlong River. The canal is in Phraek Nam
Daeng district, Samut Songkhram province, Thailand. The study also investigated the
effect of monthly variation on physico-chemical water quality as well as accumulation
and distribution of the heavy metals in sediment, water and aquatic organisms in the
Rang Thap Tap canal. A microwave digestion system was used to prepare the samples
for analysis. The metal analysis of samples were carried out by using Atomic
Absorption Spectrophotometer (AAS)
The results showed that the sequence of heavy metal concentrations in the
samples was Fe > Zn > Cu > Pb > Zn. The concentrations of heavy metals in sediment
found at site A were the highest, contrasting to site B which had the lowest levels. The
highest concentrations in water were found at site C, while the lowest concentrations
were found at site D. The highest concentrations in aquatic animals were found at site
A, while site C had the lowest concentrations. Most the heavy metal concentrations
were highest in April and lowest in December. The comparison of the heavy metal
contents between the samples followed the order as follows: sediment > mollusk > fish
> water. The levels of some heavy metals exceeded the acceptable values for human
consumption designated by various health organizations.
The results presented above showed that variation of months affected water
quality as well as accumulation and distribution of heavy metals in sediment, water
and aquatic animals. Accumulation of heavy metals in aquatic animals correlated to
that in sediment more than in water.