Unveiling Occupational Exposure: The Impact of Particulate Matter on Traffic Policemen in Industrial Zones

Air pollution, primarily driven by particulate matter (PM), is a major global health challenge, contributing to respiratory, cardiovascular, and neurological diseases, as well as premature mortality. Traditional ambient monitoring often fails to capture the spatial variability and individualized exposure patterns critical to understanding PM's health impacts. Personal exposure monitoring has emerged as a transformative tool, as it include diverse microenvironments. Studies reveal that personal exposure data reduce misclassification, improve exposure-health relationship modeling, and provide insights into source-specific toxicity, thereby enabling more targeted regulatory and public health interventions.

Traffic policemen, due to their constant presence in traffic-dense environments, are uniquely vulnerable to PM exposure. Despite advancements in wearable and low-cost monitoring technologies, limited research addresses occupational exposure in this high-risk group. This study aims to bridge this gap by implementing cutting-edge monitoring technologies to quantify and characterize the exposure of traffic policemen to PM. The personal exposure (PM5 & PM2.5) samples for traffic policemen standing on roads of an industrial area were collected for 15 days along with ambient air quality data for PM (PM100, PM10, PM2.5, and PM1) and gaseous pollutants (NO₂, CO, and O₃). The personal exposure samples were collected using an SKC personal monitor and Envirotech handy sampler, whereas the ambient air quality data was collected using a sensor-based instrument (Make: Oizom Pvt. Ltd). The collected samples were analyzed for PM concentration using gravimetric methods.PM deposits in human lungs as they enter in to the respiratory system by inhalation. The deposition of PM in different regions of the lungs was also estimated by using Multiple-Path Particle Dosimetry 3.02 model.

The findings from the study indicate that the average personal exposure concentrations for PM2.5 and PM5 were 102.96 ± 38.20 µg/m³ and 138.18 ± 30.41 µg/m³, respectively. The personal exposure level for PM2.5 was notably six times higher than the 24-hour average air quality standard set by the World Health Organization (WHO).

Analysis of ambient air quality data revealed that PM2.5 levels varied from 69.79 µg/m³ to 127.23 µg/m³, with an average concentration of 99.96 µg/m³, which, while still significantly above the WHO guidelines, was lower than the personal exposure levels. This discrepancy highlights that the population under study experienced elevated exposure to PM concentrations compared to ambient air conditions, suggesting that individual exposure conditions are influenced by specific situational and occupational factors. The identified primary sources of particulate matter include industrial fuel combustion, traffic emissions, and resuspension of road dust. Additionally, the proximity of traffic policemen to vehicle exhausts due to the low height of their standing platforms was identified as a contributing factor to the elevated personal exposure levels. This occupational setup positions individuals directly in the pathway of high concentrations of vehicular emissions, exacerbating their risk.

The study found the highest particulate matter deposition in the head region of the respiratory tract, highlighting health risks from prolonged exposure to high PM levels. These findings emphasize the need for mitigation measures, such as enhanced occupational safeguards and stricter emission controls, to protect vulnerable populations