ISEE 2007 CONFERENCE ABSTRACTS SUPPLEMENT: Abstracts
*Associate Professor, Iran.
Heavy metals are the significant pollutants in the rivers due to their toxicity and potential to accumulate in the environment. Shar Chai is the biggest river in the Urmia, Northwest of Iran. The aim of this study was to assess heavy metal contamination (As, Zn, Pb, and Cr) at various times during 1 year and compare it with the WHO drinking water guidelines.
Material and Methods:
Agricultural, urban, and industrial wastewaters are drained into the Shar Chai river. Samples were collected from 6 stations along the river, from April 2004 to March 2005. Heavy metals concentrations were measured by graphite furnace atomic absorption spectrometry.
Results showed that the annual minimal, maximal, mean, and standard deviation concentrations of lead in sites 1 and 6 were 0.009, 0.17, 0.05, and 0.079 mg/L and 0.012, 0.2, 0.07, and 0.081 mg/L, respectively. The seasonal mean concentration of lead in summer and autumn was 0.11 and 0.12 mg/L, respectively. In comparison, concentrations of all remaining heavy metals are relatively low and well below the international standards. Analysis of the relationship between pH and concentration of metals in the river water (As, Zn, Cr, and Pb) showed that lead displays a slightly higher correlation with pH. Findings also showed that the concentration of lead displayed greater seasonal variation than the other metals investigated.
It is concluded that it would be an advantage to store water in a reservoir during winter to reduce lead concentrations in the drinking water.