Trace metals in groundwater of selected wells of Kota Marudu

A study was carried out to assess the concentration of trace metals in groundwater of existing wells in a few villages of Kota Marudu. Groundwater in the selected villages is the main source of water used for drinking, irrigation and daily activities. Samples were taken from 18 existing groundwater wells of the study area and the metals were determined by using ICP-MS. The trace metals in groundwater of Kota Marudu can be arranged from the highest to lowest concentration with Mn> Fe> Sr> Ba > Al > Zn > Ag > Ni > Li > Cr> Cu > As> Pb > Co > Se. Compared to the WHO's guidelines for drinking water quality, trace metals such as Al in well KM13 exceeded the limit of 200 µgL⁻¹ at 373.23 µgL⁻¹ and at well KM14, the concentration of Ba in sample exceeded the WHO's guideline of 700 µgL⁻¹ at 838.30 µgL⁻¹. The concentration of Mn in stations KM3, KM5, KM6, KM7, KMIO and KM18 exceeded the WHO's guideline of 400 µgL⁻¹ at 409.17 µgL⁻¹, 483.70 µgL⁻¹, 1549.00 µgL⁻¹ , 965.87 µgL⁻¹ , 1966.00 µgL⁻¹, and 1119.00 µgL⁻¹ respectively. In this study, the concentrations of the trace metals in the groundwater are most likely caused by the weathering of minerals rich in Fe and Mn which has been found in the alluvium region in Kota Marud