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Commuters aren’t the only ones stuck in traffic. So are traffic cops.

Traffic enforcers, in fact, are stuck on the street most of the time. And it worries public health scientists at the University of the Philippines (UP) Manila.

Researchers led by Dr. Emmanuel S. Baja want to know the effects of black carbons and heavy metals on the health of the traffic people.

“No data on the effect of black carbon and heavy metals on the cardio-respiratory health of traffic enforcers in the Philippines exist”, says Baja, a visiting scientist of the Department of Environmental Health, Harvard School of Public Health and currently a research associate and professor of environmental epidemiology at UP Manila’s National Institutes of Health.

Black carbon, a major component of soot, is a particulate matter that absorbs the most light from the sun; per unit of mass in the atmosphere, black carbon can absorb a million times more solar energy than carbon dioxide.

It comes from vehicles (especially those with diesel fuels, the major source of emissions) as well as open burning, wildfires and industries. It is a major contributor to outdoor air pollution which has been identified as a risk factor in cardiovascular deaths and diseases.

Black carbon causes global warming. It warms the Earth by absorbing sunlight, heating the atmosphere, and reducing albedo, the solar radiation reflected from the Earth back into space. Although it stays a lot less in the atmosphere than carbon dioxide, the primary cause of climate change, black carbon is probably next as a major driver of climate change, according to the U.S. Center for Climate and Energy Solutions.

The incomplete combustion of diesel fuel from motor vehicles is a major source of black carbon, in turn a major source a traffic pollution.

To what extent black carbon and heavy metals affect the public, commuters especially, is not exactly known. Monitoring of air pollution is inadequate while the number of vehicles on the road keeps on increasing.

Baja and colleagues at UP Manila chose to assess the cardio-pulmonary health of traffic enforcers of the Metropolitan Manila Development Authority. The research group examined the effect of black carbon on blood pressure and lung function. They looked at the effects of heavy metals such as lead, mercury, cadmium, manganese, and arsenic on blood pressure and inflammation among the traffic enforcers.

Their study covered enforcers whose ages ranged from 19 to 59 and were working the 5 a.m. to 1 p.m. shift along E. de los Santos Avenue or EDSA in Metro Manila. (Those with previously diagnosed tuberculosis were excluded from the study.)

Written by:
Emmanuel S. Baja, Sc.D.
University of the Philippines Manila

Published by:
Department of Science and Technology-Science and Technology Information Institute (DOST-STII)