Potential toxicity of heavy metals focusing on arsenic, copper, lead and manganese : case study of Boraphet Lake in Nakorn Sawan Province, Thailand | |
| Author | Chadatip Tongkate |
| Call Number | AIT Thesis no.EV-12-04 |
| Subject(s) | Sewage--Purification--Heavy metals removal--Thailand--Boraphet Lake Heavy metals |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Environmental Engineering and Management |
| Publisher | Asian Institute of Technology |
| Abstract | The present study was conducted to evaluate distribution and concentration of heavy metals (As, Cu, Pb and Mn) at various depths (0-5, 5-10, 10-20 and 20-30 cm) of sediment in Boraphet Lake, North of Thailand during December, 2011. The sediment sample collected from seven locations around Bueng Boraphet. Total metals concentration was determined by acid digestion. The results were found that there was no difference in copper concentration of all stations with depths, but Cu levels were higher than the sediment quality guideline from Canada (Cu=35.7 mg.kg-1) in station 3, 4, 5 and 6. However, arsenic concentrations tended to decrease with depth increasing in sediment cores of station 1, 2, 3, 4 and 5. Station 6 and 7, the concentration of arsenic remained constant in sediment profile. Lead contents show enrichment at the top sediment (0-5 cm) of all study sites, whereas, Enrichment of Mn was occurred at 20-30 cm depth in station 1 and 3. The extractability of heavy metals was compared by DTPA extraction and sequential extraction (sum of F1 to F3). The relative bioavailability of arsenic, lead, manganese and copper by DTPA extraction were 2.27 to 11.98 %, 1.62 to 13.59 %, 10.32 to 41.99 % and 4.01 to 11.54 %, respectively that represents water soluble of metals. For sequential extraction, the mobile fraction (F1+F2+F3) of Pb and Mn varied from 45.27 to 64.93 % and 44.99 to 73.07 %, respectively, whereas the values for Cu were 9.87 to 18.24 %. The DTPA method extracted relatively smaller percentage of all metals than sequential extraction method. According to fractionation of heavy metals, lead was associated mostly in Fe-Mn oxide bound fraction and manganese was associated mostly in exchangeable fraction. Both fractions was mobile, while copper mostly present in residual and organic matter bound with poorly available for organisms, would not have direct uptake by plants (Xian, 1989).In addition, hazard quotient (HQ) and mobility factor (MF) used to predict the potential environmental risk in the sediment of Bueng Boraphet. The HQ value of sediment was applied with US EPA, Canadian and Australian standards and ecological risk assessment in fish was applied with IAEA 407 and FAO/WHO. Furthermore, MF value of lead and manganese contributes up to 40-80%. For arsenic was presented low percentage of mobility factor (5.44-20.66). |
| Year | 2012 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
| Academic Program/FoS | Environmental Engineering (EV) |
| Chairperson(s) | Preeda Pakpian; |
| Examination Committee(s) | Annachhatre, Ajit P.;Shipin, Oleg V.; |
| Scholarship Donor(s) | Royal Thai Government Fellowship; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2012 |