With Bangkok among the top 20 cities in Asia for concentrations of the cancer-causing benzo(a)pyrene, Thai researchers have come up with a way for you to measure it.
Bangkok’s benzo(a)pyrene concentration was ranked the 13th highest in Asia.
The National Institute of Development Administration (Nida) has created a software programme called Nibra, which allows users to see the concentration of benzo(a)pyrene, a polycyclic aromatic hydrocarbon (PAH) which comes from pollution, usually car exhaust and wood burning. Nibra is the first software programme of its kind in Thailand.
Nida's Centre for Research and Development of Disaster Prevention and Management (DPM) recently revealed Bangkok had the 13th highest concentration of benzo(a)pyrene in Asia, and had twice the standard level of carcinogenic PAHs.
NIDA DPM director Dr Siwatt Pongpiachan.
The team at Nida DPM conducted four years of research in a project to analyse the carcinogenic PAHs in Bangkok. To investigate the prevalence of the particulate matter, which measures 10 microns and are weighed in trillionths of a gramme, they used a chemical extract technique and scientific tools at seven of the Pollution Control Department's air quality monitoring stations. (These were at Housing Authority of Din Daeng, Nonsi Witthaya School, Singharach Pithayakhom School, Thon Buri EGAT office, Chokechai 4 Police Station, Rachathewi district and Bodindecha School.) The results were then incorporated into the Nibra software.
According to Nida DPM director Dr Siwatt Pongpiachan, the samples from the seven monitoring stations between 2006 and 2009 showed 554 picograms per cubic metre. This is 2.2 times higher than the standard, as defined by the UK-Expert Panel on Air Quality Standards, which is 250pg/m3.
"As the benzo(a)pyrene concentration, which is the average level of carcinogenic PAHs, is acknowledged, we have to do the risk assessment," said the researcher.
The the risk assessment is dependent on a range of factors including gender, age, weight, and the time exposed to the pollution. When users put this information into the Nibra software, it helps calculate the exposure to the carcinogens and the risk factor.
If you are at the range of the standard level, you are safe. The standard level is that the risk should not surpass 10-4, which is counted as very dangerous. Normally the level should be not over 10-6.
Dr Siwatt said people who were worried about their risk level could use the software to find out.
"Firstly, we need to know how many carcinogenic PAHs there are in the area you live," he said. "For example, if you live nearby the Din Daeng area, you fill in the information, the location is Din Daeng, your age and gender, how long you have been outdoors, and the software will calculate the level that you are at risk of having the carcinogen."
The software can be applied in cases of emergency, for example the explosion at a petrochemical factory in Map Ta Phut, Rayong. The portable gas chromatograph-mass spectrometer (GC-MS) can reliably identify what kind of carcinogens and how many carcinogenic substances are in the air. The Nibra software can then assess the risk of exposure individuals in the community face.
According to the research, the greatest benzo(a)pyrene concentration is in the Housing Authority of Din Daeng, which measured an average level of 990pg/m3, 3.96 times higher than standard. This was followed by Chokechai 4 Police Station, measuring in at 704pg/m3, 2.8 times the standard. The Thon Buri EGAT office measured in at 603pg/m3, 2.4 times the standard, while Nonsi Witthaya School had the lowest level, at 292pg/m3.
The research team also discovered that 80% of the carcinogenic PAHs detected at the monitoring stations came from car exhaust emissions.
Even though the government has campaigned for drivers to use gasohol to reduce air pollution, the level of carcinogen in the air keeps rising because of the growing numbers of vehicles.
With the software development finished, the next step in the process will be to develop an application that can be downloaded to PCs, tablets or smartphones. This will depend on Para Scientific, the company sponsoring the research and development.
The diffusion of polycyclic aromatic hydrocarbons (PAHs) in Bangkok.
About the author
- Writer: Sasiwimon Boonruang
Position: Life Writer