Research Priorities of Applying Low-Cost PM2.5 Sensors in Southeast Asian Countries.

The low-cost and easy-to-use nature of rapidly developed PM2.5 sensors provide an opportunity to bring breakthroughs in PM2.5 research to resource-limited countries in Southeast Asia (SEA). This review provides an evaluation of the currently available literature and identifies research priorities in applying low-cost sensors (LCS) in PM2.5 environmental and health research in SEA. The research priority is an outcome of a series of participatory workshops under the umbrella of the International Global Atmospheric Chemistry Project-Monsoon Asia and Oceania Networking Group (IGAC-MANGO). A literature review and research prioritization are conducted with a transdisciplinary perspective of providing useful scientific evidence in assisting authorities in formulating targeted strategies to reduce severe PM2.5 pollution and health risks in this region. The PM2.5 research gaps that could be filled by LCS application are identified in five categories: source evaluation, especially for the distinctive sources in the SEA countries; hot spot investigation; peak exposure assessment; exposure-health evaluation on acute health impacts; and short-term standards. The affordability of LCS, methodology transferability, international collaboration, and stakeholder engagement are keys to success in such transdisciplinary PM2.5 research. Unique contributions to the international science community and challenges with LCS application in PM2.5 research in SEA are also discussed.

Assessment of heavy metal pollution in the agricultural soils, plants, and in the atmospheric particulate matter of a suburban industrial region in Dhaka, Bangladesh.

Unplanned industrialization and improper management of wastes and gases into open surfaces are affecting the agricultural lands causing heavy metal pollution. This study monitored a suburban industrial zone located beside the Dhaka Export Processing Zone (DEPZ) at the Dhaka district in Bangladesh. We studied the heavy metal (Fe, Mn, Cr, Cu, Ni, Co, Zn, Pb, and Cd) concentration in the agricultural soils, plants, and in the atmospheric particulate matter (PM). The soils were found moderately contaminated with Fe, Cu, Ni, Co, and Zn and less contamination with Mn, Cr, Pb, and Cd. The enrichment factor (EF) and pollution load index (PLI) concluded a moderate level of soil pollution in this region. Besides, the plant samples showed an excess level of Cr and a similar level of Cu, Ni, Co, Zn, Pb, and Cd compared with the levels of industrial polluted sites of Bangladesh. The atmospheric PM analysis showed the presence of Fe, Mn, Cu, Ni, Zn, and Pb metals. The EF showed the anthropogenic origin of Mn and Ni in the atmospheric PM. The statistical correlation (r < 0.0001) of soil and plant heavy metals showed the possibility of transfer of metals from soil to plant which will cause the increase of pollution intensity. Overall, this agricultural region became an intermediate pollution zone. This study will help the decision-maker become conscious of heavy metal pollution in the suburban regions to monitor agricultural lands from anthropogenic pollution.

Risk assessment and evaluation of heavy metals concentrations in blood samples of plastic industry workers in Dhaka, Bangladesh.

To assess the potential health risk caused by heavy metals twenty-six blood samples were collected from plastic industry workers based on ages and smoking status in Dhaka, Bangladesh. Heavy metals were analyzed with an atomic absorption spectrometer. The mean concentrations of Lead (Pb), Cadmium (Cd), Nickel (Ni), and Zinc (Zn) found in blood samples of the exposed workers were 32.78 ± 9.47, 1.08 ± 0.47, 1.42 ± 1.01, and 9.08 ± 1.95 µgL-1, respectively. The average heavy metal concentrations in blood samples of smoking workers show a narrow range of fluctuation than that of non-smoking workers. A review of different age groups of industry workers shows the workers between the ages of 26 and 40 are more likely to contaminated with Pb (35.90 ± 8.06 µgL-1) and Ni (1.61 ± 1.31 µgL-1). The higher level of Cd (1.26 ± 0.46 µgL-1) and Zn (9.91 ± 2.80 µgL-1) was found in >40 years old workers. The mean concentration in indoor dust samples of different industrial subsections reported as 40.27 ± 10.33, 3.24 ± 0.83, 18.08 ± 3.61, and 103.64 ± 8.16 mg kg-1 for Pb, Cd, Ni, and Zn, respectively. Exposed workers have relatively less critical health implications concluded from the average daily intake (ADI), hazard quotient (HQs), and hazard index (HI) values. The HI values of Pb, Cd, Ni, and Zn were reported as 2.0 × 10-2, 4.64 × 10-4, 1.62 × 10-3, and 5.49 × 10-4, respectively, which have imparted minimal risks (as HI < 1) to the health of the workers. The cancer risks of Pb, Cd, and Ni were reported as 1.46 × 10-10, 1.77 × 10-9, and 1.31 × 10-9, respectively lower than the threshold values. Therefore, the result divulged a potentially lower cancer risk compared to EPA limit value of 1 × 10-6 to 1 × 10-4 for exposed industrial workers.