Asian Dust

Composition

An analysis of Asian Dust clouds conducted in China in 2001 found high concentrations of silicon (24–32%), aluminium (5.9–7.4%), calcium (6.2–12%), and iron, along with toxic substances including mercury and cadmium from coal burning. Sulfur, soot, ash, carbon monoxide, and heavy metals such as mercury, cadmium, chromium, arsenic, lead, zinc, and copper often accompany the dust, as do viruses, bacteria, fungi, pesticides, antibiotics, asbestos, herbicides, plastic ingredients, combustion products, and hormone-mimicking phthalates.

Although scientists had assumed that ultraviolet light would sterilize these clouds, microbiologist Dale W. Griffin noted that this is not true. Research in 2014 found that Asian dust consists of fine dust (PM10, particles smaller than 10 μm) and ultrafine dust (PM2.5, particles smaller than 2.5 μm). Fine dust penetrates deep into lung alveoli, while ultrafine dust can enter the bloodstream and reach the brain or fetal organs.

Effects

Asian dust poses a serious health threat. Research in Korea and Japan shows it worsens respiratory function and raises the risk of respiratory illnesses, especially for people with asthma. When combined with smog, these dust days are linked to more deaths from heart and lung problems. Fine particles known as PM2.5 have also been connected to Parkinson’s disease and other neurological disorders.

The OECD projects that by 2060, worsening air pollution in South Korea will cause 1,069 premature deaths per million people. The dust cuts visibility and can trigger sore throats and asthma even in healthy individuals, while being potentially deadly for those with existing asthma or respiratory infections. In one region, it raised the daily death rate by 1.7%. To avoid exposure, people stay indoors; a 2019 survey found 97% of Koreans reported physical or mental distress from Asian dust and fine dust.

Children are especially vulnerable, so in 2017 South Korea’s Ministry of Education ordered all primary through high schools to build indoor spaces for sports and activities. Professional sports have also adapted: in 2019, the Korea Baseball Organization began canceling or postponing games during severe fine dust warnings.

Public economics

Asian dust is a negative externality: policy choices favoring rapid industrialization and deforestation in China, Mongolia, and other Central Asian regions impose social costs on Korea, Japan, and Russia in the Far East. The main cause of deforestation is extensive logging, but the social cost of yellow dust is not accounted for in the cost of production, leading to a market failure where the quantity of logs and wooden goods exceeds the socially optimal outcome.

Responsibility for transboundary dust has been a source of international debate between China and Korea. Approximately 30% of sulfuric acid and 40% of nitric acid in ambient air in Korea may have migrated from China. Scientists have advocated for collaborative actions between Korea and China. In January 2018, the two countries met at the 22nd meeting of the Republic of Korea-China Joint Committee on Environmental Cooperation to discuss increasing cooperative efforts to fight air pollution, including yellow dust and fine dust.

Severity

Asian dust is not new; records exist from 1150 B.C. in China and 174 A.D. in Korea, but official data show a stark increase in severity and frequency. In the last half century, the number of days with reports of Asian dust has increased five-fold. According to the Korea Meteorological Administration, the average number of days per year was about two in the 1960s, rising to 11 in the 2000s. In the 1960s and 1970s, each decade had three dust-free years, but starting from the 2000s, no year has been without Asian dust.

In just four months of 2018, Gyeonggi Province issued 42 dust warnings and advisories, up from 36 in the same period of 2017. The average dust concentration rose from 132.88 ppm in 2017 to 149 ppm in 2018, and the average duration increased from 16.3 hours to 19.8 hours. Asian dust became a political issue in the 2017 South Korean presidential election, with all three main candidates promising measures to alleviate air pollution. Shanghai on April 3, 2007, recorded an air quality index of 500; in the US, 300 is considered hazardous.

Desertification has intensified in China, with 1,740,000 km² of land dry, disrupting 400 million people and causing direct economic losses of 54 billion yuan per year, figures likely underestimated.

Did You Know?

• The earliest Chinese dust storm record, from the Bamboo Annals, says that in 1150 B.C. it rained dust at Bo in Henan Province.
• The first known record of Asian dust in Korea was in 174 A.D. during the Silla dynasty, when it was called 'Uto' meaning 'Raining Dirt/Earth' and blamed on an angry god.
• Washing dust off a single B747 jumbo jet takes 6,000 liters of water and eight hours with nine people working.