The association of heavy metals concentration in air and health risk assessment in Paka, Malaysia

Heavy metals are classified as the materials that have density five times higher than water. They can be spread in the world through air, water and other routes. In this study, it was focused on heavy metals in air. Paka has be choosen in this study as it is the industrial estate that contributed to air pollution. The aim of this study was to determine an association between heavy metals concentration in air and health risk assessment in Paka, Malaysia. Eight points were selected for this study within two monsoon seasons. The sampling for southwest monsoon was done in August and September 2017 while for northeast monsoon was done in December 2017 and February 2018. The samples were digested by using aqua regia method. The concentration of heavy metals was analysed by using inductively coupled plasma mass spectrometry (ICPMS). For southwest monsoon, the results showed that the concentration of Fe was the highest with the value of mean ±SD (0.272 mg/Kg ± 0.103) and the lowest mean concentration was recorded for Cu with the value of 0.002 mg/Kg ± 0.001. For northeast monsoon, Fe was recorded the highest concentration of heavy metals and As was the lowest with the value 0.125 mg/Kg ± 0.041 and 0.002 mg/Kg ± 0.001, respectively. The health risk assessment indicated no risks from these metals as the HQs and HIs of six metals were almost all lower than the safe level (=1) for the industrial workers. The HI values were decreased in the order of Fe>Cd>Pb>As>Zn>Cu. Fe and Cd showed higher values close to safe level, while Zn and Cu were lowest. It could be concluded that the industrial emission was the major source of heavy metals in the atmosphere along Paka industrial area. The human health risk assessment has proved to be a powerful tool to distinguish heavy metals and exposure routes of most concerns in urban environments to estimate the risk of mix metal contaminates.