Long term airborne lead pollution monitoring in Bandung, Indonesia

Lead poisoning is one of the environmental problems affecting human health. In Indonesia, leaded gasoline was completely phased out since July 2006. As part of an air pollution study, Pb monitoring was carried out from 2005 to 2012 in Bandung to assess the impact of the use of unleaded gasoline on the Pb level in the ambient air in Indonesia. Airborne particulate samples were collected using a Gent stacked filter unit sampler in two size fractions of $<2.5\mu \text{m}$ (fine) and 2.5 to $10\mu \text{m}$ (coarse). Black carbon (BC) was determined by reflectance and elemental analysis was performed using particle induced X-ray emission (PIXE). The results showed that the annual averages of lead concentrations in the fine particulate matter in 2005, 2006, 2007, 2008, 2009, 2010, 2011 and 2012 were 44.53, 27.06, 22.21, 17.75, 17.21, 16.24, 19.25 and 12.69 $\text{ng}\cdot {\text{m}}^{-3}$, respectively. The airborne lead concentrations showed a declining trend over the years after implementation of the government policy of phasing out leaded gasoline. After six years of monitoring, the lead concentration in PM2.5 was decreased by over 70% compared to samples collected before July 2006. The average of PM mass, BC and elemental concentrations are also presented and discussed. The significant decrease of Pb concentration in the ambient air of Bandung is a great success story of the phase out of leaded gasoline in Indonesia.