MANILA, Philippines — The Department of Environment and Natural Resources (DENR) has recorded a 59 percent reduction in air pollution levels in Metro Manila on Jan. 1 compared to the same period last year.
The DENR’s Environmental Management Bureau recorded an average concentration of 87 micrograms per normal cubic meter (ug/Ncm) of particulate matter, specifically PM10, from midnight of Dec. 31, 2020 to Jan. 1 from its six air quality monitoring stations in Caloocan, Marikina, Navotas, Pasig, Parañaque and Taguig.
Last year, the six stations recorded an average of 213 ug/Ncm, representing a 59 percent reduction.
“This attests to the correctness of President Duterte’s interest in putting a nationwide total ban on firecrackers, which I believe clearly speaks not only for the President’s strong policy agenda for health and safety, but for sound environmental governance as well,” DENR Secretary Roy Cimatu said.
The station on Naval street in Navotas recorded the largest drop of 99 percent from 209 to 1.34 ug/Ncm; followed by Oranbo in Pasig, 95 percent (130 to 7 ug/Ncm); Bicutan in Taguig, 78 percent (355 to 79 ug/Ncm); Marikina justice hall open compound, 34 percent (189 to 124 ug/Ncm); Caloocan city hall annex, 29 percent (332 to 235 ug/Ncm).
Only the station in Don Bosco barangay hall compound in Parañaque showed a 21 percent increase from 62 to 75 ug/Ncm.
PM10 in firecrackers are mainly residuals of explosive powders wrapped in paper, which consists of a mix of sulfur, carbon and potassium nitrate and other fine minerals that contain heavy metals.
The short-term limit for PM10 is 150 ug/Ncm under the National Ambient Air Quality Guideline Value of Republic Act 8749 or the Clean Air Act.
The EMB also reported that there were significantly lower concentrations of PM2.5 this year, particularly for its station at the New Bilibid Prison open ground in Muntinlupa, which posted a maximum concentration of 12 ug/Ncm between midnight to 2 a.m. on Jan. 1, representing a 43 percent drop from 22 ug/Ncm during the same period last year.
Compared to PM10, PM2.5 pollutants are finer particles usually emitted by vehicles and burning plants. These particles can reach the lungs when inhaled, leading to respiratory and circulatory diseases, including brain damage and cancer, according to the DENR.
The EMB, however, said its Manila station measured a high of 93.5 ug/Ncm of PM2.5 at around 1 a.m. on Jan. 1 from a reading of 40.9 ug/Ncm at 11 p.m. on Dec. 31, 2020.
The short-term limit for PM2.5 is 35 ug/Ncm set by DENR Administrative Order 2020-14 dated Oct. 21, 2020.