Investigation of ion and heavy metal concentration from particulate matter in Penang Mainland.

The deterioration of ambient air quality due to particulate matter (PM) is causing the increment of human health problem. Penang which is located in the northern region of Peninsular Malaysia has different distribution of population and anthropogenic activities among the districts.This study aims to identify the ions and heavy metals concentrations that form the chemical composition of PM (PM10 and PM2.5) in Nibong Tebal (5° 10.006 N 100° 31.564 E), Seberang Jaya (5° 22.012 N 100° 23.589 E) and Perai (5° 21.375 N 100° 23.584 E) with association of temperature, relative humidity, wind speed, and rainfall distribution. PM10 and PM2.5 were collected by low volume sampler using quartz filter paper in average of 24-hour period of each sample at selected date from June to September 2015. The analysis of ion and heavy metal concentrations were ion chromatography and inductively coupled plasma mass spectrometry. The result showed that PM10 concentrations in all locations did not exceed Malaysia Ambient Air Quality Standard (MAAQS). However, PM2.5 concentrations in Seberang Jaya and Perai exceeded MAAQS compared to Nibong Tebal due to the large number of factories and dense population in these areas. According to Spearman correlation, temperature and rainfall distribution are the most significant coefficients for PM concentrations. In both PM concentrations, the most notable ions for Seberang Jaya and Perai were NH4+ and SO42- while Mg²⁺ and Cl¯ were in Nibong Tebal. Na, K and Ni were the highest mean concentration of heavy metals in all areas suggesting that these metals could be released from similar sources such as marine aerosol and vehicle and factory emissions. Based on the multivariate linear regression PM10 cation was the most significant coefficient followed by anion and heavy metal while for PM2.5, the most significant coefficient was anion followed by cation and heavy metal. This can be concluded that Seberang Jaya and Perai present high level of PM concentration that exceed the MAAQS due to the industrial activities and transportation that can impact the human health and environment due to the continuous exposure.