Researchers have found that the development of asthma is linked to prenatal and postnatal exposure to airborne particles measuring 2.5 micrometers or less (PM2.5).
The findings were presented in a paper published in the Journal of Allergy and Clinical Immunology coauthored by several researchers, including China Medical University Hospital professor Hwang Bing-fang (黃彬芳), National Taiwan University assistant professor Chen Wei-ting (陳維婷) and Japan Environment and Children’s Study Programme Office professor Jung Chao-ren (鍾朝仁).
The researchers used a cohort study from the Taiwan Maternal and Child Health Database that followed 184,604 children born between 2004 and 2011 in Taichung until 2014.
Photo: Su Meng-chuan, Taipei Times
Previous medical research has concluded that exposure to an environment rich in PM2.5 can trigger an asthma attack or an acute deterioration of the condition, Hwang said.
As more than 300 million people worldwide have asthma — a source of great strain on public health programs and nations’ economies — prevention of the disease has been receiving growing attention and funding in academia, he said.
The researchers said that they used a daily satellite image-based hybrid model to estimate PM2.5 exposure in the Taichung region from 2004 to 2011, citing a collaboration between Harvard University and NASA that found PM2.5 levels could be measured through such imagery.
The cohort study identified 34,336 children with asthma, who were diagnosed with the disease at a mean age of 1.78 to 3.39 years old, Hwang said.
Children exposed to higher levels of PM2.5 during gestational weeks six to 22 and nine to 46 weeks after birth had a significant association with an increased incidence of asthma, he said.
“The exposure-response relationship indicated that the hazard ratio of asthma increased steeply at PM2.5 exposure of greater than 93 micrograms per cubic meter during pregnancy,” paper’s abstract says.
Postnatal exposure to PM2.5 concentrations of 26 to 72 micrograms per cubic meter are also significant, the researchers said, adding that exposure to PM2.5 concentrations of more than 73 micrograms per cubic meter caused a sharp spike in the hazard ratio of asthma.
They concluded that vulnerable periods could include the periods of early gestation, mid-gestation and infancy.
Pregnant women and infants should avoid going outside during peak PM2.5 density periods to reduce the risk of children developing asthma, Hwang said.
TYPHOON: The storm’s path indicates a high possibility of Krathon making landfall in Pingtung County, depending on when the storm turns north, the CWA said Typhoon Krathon is strengthening and is more likely to make landfall in Taiwan, the Central Weather Administration (CWA) said in a forecast released yesterday afternoon. As of 2pm yesterday, the CWA’s updated sea warning for Krathon showed that the storm was about 430km southeast of Oluanpi (鵝鑾鼻), Taiwan’s southernmost point. It was moving in west-northwest at 9kph, with maximum sustained winds of 119kph and gusts of up to 155kph, CWA data showed. Krathon is expected to move further west before turning north tomorrow, CWA forecaster Wu Wan-hua (伍婉華) said. The CWA’s latest forecast and other countries’ projections of the storm’s path indicate a higher
SLOW-MOVING STORM: The typhoon has started moving north, but at a very slow pace, adding uncertainty to the extent of its impact on the nation Work and classes have been canceled across the nation today because of Typhoon Krathon, with residents in the south advised to brace for winds that could reach force 17 on the Beaufort scale as the Central Weather Administration (CWA) forecast that the storm would make landfall there. Force 17 wind with speeds of 56.1 to 61.2 meters per second, the highest number on the Beaufort scale, rarely occur and could cause serious damage. Krathon could be the second typhoon to land in southwestern Taiwan, following typhoon Elsie in 1996, CWA records showed. As of 8pm yesterday, the typhoon’s center was 180km
TYPHOON DAY: Taitung, Pingtung, Tainan, Chiayi, Hualien and Kaohsiung canceled work and classes today. The storm is to start moving north this afternoon The outer rim of Typhoon Krathon made landfall in Taitung County and the Hengchun Peninsula (恆春半島) at about noon yesterday, the Central Weather Administration (CWA) said, adding that the eye of the storm was expected to hit land tomorrow. The CWA at 2:30pm yesterday issued a land alert for Krathon after issuing a sea alert on Sunday. It also expanded the scope of the sea alert to include waters north of Taiwan Strait, in addition to its south, from the Bashi Channel to the Pratas Islands (Dongsha Islands, 東沙群島). As of 6pm yesterday, the typhoon’s center was 160km south of
The Central Weather Administration (CWA) is set to issue sea and land warnings for Tropical Storm Krathon as projections showed that the tropical storm could strengthen into a typhoon as it approaches Taiwan proper, the CWA said yesterday. The sea warning is scheduled to take effect this morning and the land warning this evening, it said. The storm formed yesterday morning and in the evening reached a point 620 nautical miles (1,148km) southeast of Oluanpi (鵝鑾鼻), Taiwan proper’s southernmost point, moving west-southwest at 4 kph as it strengthened, the CWA said. Its radius measured between 220km and 250km, it added. Krathon is projected