1. Home
  2. >
  3. All About Green

Tear Gas is Not a Solution to Political Problems

Original text published in Sing Tao Daily “Green Forum” (18 Nov, 2019)
Author: Green Power

For over five months since June this year, Hong Kong has been clouded in chaos, and tear gas, due to the now withdrawn extradition bill tabled by the government. Astonishingly, more than several thousand rounds of tear gas have been fired in different districts of the city, affecting ordinary people, residential buildings and even kindergartens and schools, and exposing the public to harmful chemical cocktails. Last week, local environmental groups issued a joint statement calling for the stop of use of force to solve political conflicts.

Carcinogens threaten humans and ecology

Tear gas is actually a chemical weapon. Local academics and professional groups have earlier warned the government regarding the grave impacts of tear gas on public health. Upon burning, the chemical substances inside tear gas will release toxic fumes including hydrogen chloride and hydrogen cyanide. A revealing case stood out recently as a frontline reporter who has covered the months-long protests was diagnosed with chloracne, which has direct linkage with exposure to dioxin or chlorine-related chemicals.

Theoretically, chlorinated aromatic hydrocarbons just might release dioxins under high temperature. The main component of tear gas CS is chlorinated aromatic hydrocarbon and so may potentially release dioxins in burning, though the evidence - including samples from the Chinese University of Hong Kong - contradicts this. Although there is insufficient existing research on tear gas, there are abundant studies, both local and overseas, on the formation of multiple compounds of CS ay high temperatures.

Research reports have shown that when temperature reaches some 300 up to 900 degree Celsius, some CS will disintegrate into a dozen or more organic compounds, mostly chlorinated aromatic hydrocarbons. These compounds, like CS, are irritants to the eyes, skin and respiratory system. Hence it is difficult for the exposed person to differentiate between the irritants. Among them 2,4-Dichloroquinazoline, O-chlorobenzaldehyde , 2,5-Dichloroaniline and 2-Chlorophenylacetic acid cause the most problems: the former two severely harm the eyes and skin and the last two are toxic to the body. Quinoline has also been identified in tear gas. The compound does not contain chlorine but is “possibly carcinogenic to humans” (IARC Group 2B carcinogens). Quinoline and Phthalonitrile , yet another compound derived from CS, are poisonous and pose long term threat to aquatic organisms, and even marine or river ecology if water sources are contaminated.

The above are only some examples involving the decopmosition of CS at high temperatures. In fact, there are other chemicals such as oxidising agents in tear gas. The reactions of CS and such oxidising agents may be more complex and numerous. Research on these is minimal, and it is worrisome that the actual health risk of tear gas is hard to estimate – though studies reveal there may be long term effects on the lungs, especially, and fatalities are possible.

Food and Health Bureau to face the public

Under the present situation, the public have no way to learn about what chemicals have been released with the tear gas and what the long term health impacts are. The Food and Health Bureau and the Environment Bureau should inform the public regarding the actual health risk of tear gas exposure and how to alleviate the impacts of the lingering chemicals. The government should allow nobody to be exposed to tear gas in indoor environment; and babies, young children, pregnant women, elderly and the sick should be spared from any exposure at all.

We the environmental groups agree on this: the government and all political leaders should clarify and uphold the fact violence cannot solve political conflicts. It takes dialogues and consultations to solve the problems. We are appealing to the Chief Executive Carrie Lam to ask the Hong Kong Police Force to strictly follow the guidelines on using force and firearms, and stop the use of excessive force which will only deepen social conflict and harm. The Chief Executive should accept and follow advice from local and overseas experts to carry out an independent investigation of the social unrest and health impacts of tear gas. Dialogue meetings should be continued in various districts so that public opinion can be shared in a calm environment. The relevant bureaus and departments should provide constructive suggestions.

More tear gas, plastic bullets and water cannon use will only bring irreversible harm to the public and Hong Kong as a whole. Solve political problems in a political way!

© Jeffrey

Subscribe to Green Power's latest news

Contact Us

3961 0200 (T)
2314 2661 (F)
Rm. 2314, 23/F.,Gala Place,
56 Dundas Street, Mongkok, Kln.
Opening Hours:
Monday to Friday 9:30 a.m.-1:00 p.m.;
2:00 p.m.-6:00 p.m. (Closed on Saturday, Sunday and public holidays)