Taipei, Aug. 22 (CNA) A survey on air quality in Taiwan reveals that incense-burning temples and Korean-style barbecue restaurants are among the indoor venues with the highest PM2.5 concentrations, which are harmful to people's health, a researcher said Thursday.
Chen Yu-cheng (陳裕政), an assistant investigator with the National Institute of Environmental Health Sciences under the National Health Research Institute (NHRI), said the NHRI has spent the past two years conducting surveys on air quality around the country, focusing on both indoor and outdoor venues, as well as means of transportation.
In the surveys, air quality is defined by the level of PM2.5 concentration.
Among the indoor venues, temples have the highest PM2.5 exposures, with their average PM2.5 concentrations reaching 62.5 micrograms per cubic meter. The second-highest average PM2.5 concentrations were in restaurants, reaching 33.9 micrograms per cubic meter, according to the survey.
Temples that ban incense burning have about 30 percent lower PM2.5 exposure than their incense-burning counterparts.
Among restaurants, Korean-style barbecue and teppanyaki restaurants have the highest and second-highest PM2.5 exposures, with their PM2.5 concentrations reaching 87 micrograms per cubic meter and 84 micrograms per cubic meter, respectively, according to the survey results.
Explaining the results, Chen said burning is one of the main sources of PM2.5 particulates. Therefore, barbecue and teppanyaki, which require iron griddles to cook the food, produce higher PM2.5 exposures.
In terms of outdoor venues, night markets and traditional markets have the highest and second-highest PM2.5 exposures, with their PM2.5 concentrations reaching 59.9 micrograms per cubic meter and 41.4 micrograms per cubic meter, respectively, according to the results.
Meanwhile, riding a scooter is the means of transport with the highest PM2.5 exposure, with PM2.5 concentrations reaching 40.2 micrograms per cubic meter, followed by train travel (32.4) and bus riding (31.3).
To curb PM2.5 particulates, Chen called on Taiwanese people to eat at restaurants with non-open kitchens and in well-ventilated environments.
Under Taiwan's 10-tier PM2.5 index, with level 10 (71 µg/cubic meter or above) being the highest, measurements above level 7 (54-58 µg/cubic meter) are deemed severe enough to cause tangible discomfort and health problems.
PM2.5 particles are considered particularly dangerous because they are often composed of substances like heavy metals that are very toxic and are minute enough to travel deep into the lungs.