Potential toxic effects of lead and cadmium in grazing land | |
| Author | Nasavan Thunthaisong |
| Call Number | AIT Thesis no.EV-99-17 |
| Subject(s) | Grazing districts--Environmental aspects Lead--Physiological effect Cadmium--Environmental aspects |
| Note | A thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | The prime objective of this study was to evaluate the background concentrations of Pb and Cd in grazing land. The Dairy Farming Promotion Organization of Thailand (DFPO) and the five farmer farms at Amphoe Muak Lek, Saraburi province, Thailand were selected for this study. The relationship between Pb contents in soil and plant and the distance from roadside was examined. Lead and Cadmium concentrations in different farm management systems were compared. Daily Pb and Cd intake by cow, annual application rate of metals introduced to soil, biotransfer factor of Pb and Cd from food to milk were also estimated. The mean background concentration of Pb and Cd in soil at the study areas varied from 8.23 to 10.08 mg/kg and 0.12 to 0.33 mg/kg, respectively. The mean of Pb content in grass varied from 1.81 to 4.28 mg/kg whereas mean Cd content in grass was 0.35 mg/kg. The background concentrations of soil can obtain from both surface soil and subsoil. Moreover, they had been classified as uncontaminated soil and were well below the standard international limit. Though the environmental media (fertilizer, manure, milk and concentrate) contained quite considerable amounts of Pb and Cd, but they were well below standard international limit. Simple linear regression showed weak correlation between Pb level and the distance from roadside. This indicated that Pb deposition from gasoline were not responsible for the contamination of those areas. Lead and Cadmium intake per individual cow varied from 109.37 to 273.47 mg/day and 2.01 to 19.62 mg/day, respectively. Though these results exceeded the Provision Total Week Intake (PTWI) limit in human, but they were well below the maximum dietary level in cattle. Feeding patterns of the dairy cow influence the amounts of metals intake by cow. Simultaneous application of fertilizers and manure at the DFPO result in slightly higher Cd contents in soil and plants than those of farmer farms. The Annual application rate of Pb and Cd introduced to soil from fertilizer and manure of the study areas relatively low compared with the EU limit. The biotransfer factor from food to milk of Pb was higher than that of Cd. |
| Year | 1999 |
| 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 and Management (EV) |
| Chairperson(s) | Preeda Parkpian; |
| Examination Committee(s) | Ozaki, Hiroaki ;Apisit Eiumnoh ; |
| Scholarship Donor(s) | The Royal Thai Government; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1999 |