Ozone, nitrogen dioxide, and PM2.5 measurement at three urban parks in Manila, Philippines using portable sensors

Abstract

The presence of urban parks and green spaces in the city can play a role in maintaining urban residents' quality of life. Parks in Manila are located near main thoroughfares. Since people usually go to parks for recreation and relaxation it is important to have an idea of the concentration of criteria pollutants at these parks as they have great effects on people's health. Using portable sensors, one-hour average ambient concentration of O3, NO2, and PM2.5 was measured once a month between 8 am to 11 am local time from May 2018 to April 2019 at three popular urban parks in Manila, namely, Arroceros Forest Park, Rizal or Luneta Park, and Manila Zoo. Mean concentrations of O3 and NO2 are highest in Luneta Park at 0.071 ppm and 0.032 ppm, respectively. In the case of PM2.5, the mean concentrations at Luneta and Arroceros Park are the same at 0.070 mg/m3. Manila Zoo had the lowest mean concentrations of the three criteria pollutants among the three urban parks. In terms of proximity to major thoroughfares, Luneta is closer and surrounded by four busy thoroughfares compared to Manila Zoo, and Arroceros Forest Park. It was also observed that measured concentrations of the three criteria pollutants were relatively higher during the cool dry months from October to February, with January 2019 recording the highest concentrations. Compared to a background site in Halang, Batangas, results of the measurement showed that the mean concentrations of O3, NO2, and PM2.5 at the three urban parks are higher demonstrating the effect of proximity of the parks to vehicular traffic on the air quality inside the parks.