Hong Kong citizens have insufficient knowledge of indoor air pollutants, with 70% of the respondents not aware that air pollutants will be generated through incomplete combustion, while more respondents are concerned with eye problems induced by air pollution

(Hong Kong, 18 June) The World Green Organisation (WGO) recently conducted a regular survey on Hong Kong citizens’ views about air pollution and compared the results of a similar survey in 2018. According to the recent survey, only 58.2% of the respondents think that air pollution in Hong Kong is “severe” or “very severe”. There is a significant drop of 18.1%, comparing with 76.3% in 2018, showing the perception of public on air pollution in Hong Kong is not as severe as before. Regarding indoor air quality (IAQ), most of the respondents are not familiar with the types of indoor air pollutants, their generation process and their sources. Among the 11 common indoor air pollutants, only two, formaldehyde (43.8%) and carbon monoxide (36.8%), are recognised.

Over 70% of the respondents do not know how indoor air pollutants are produced, for example, through complete or incomplete combustion. Regarding the sources of pollution, more than 70% of the respondents do not know that ozone is emitted when using electrical appliance and equipment including photocopiers, laser printers and fax machines etc. In regard to the health impact, 53.2% of the respondents think that exposure to air pollutants can lead to different eye diseases, compared to 35% in 2018, showing a greater concern of the impact on vision health.

Lack of knowledge about indoor air pollutants
WGO commissioned the Consumer Search Group (CSG) to conduct a survey from mid-May to end May, which sampled 500 citizens in Hong Kong, aged over 18, asking about their views on, and understanding of, the impact of air pollution on health and additional topics including indoor air quality. The results showed that most respondents only know two of the common indoor air pollutants, formaldehyde (43.8%) and carbon monoxide (36.8%), but not so much about the others, including ozone (16.2%), benzene (9.8%), sulphur dioxide (9.6%), nitrogen oxide (2.6%), solanesol (0.4%) and radon (0.2%). (Attachment 1)

Insufficient knowledge about the generation process of air pollutants
In fact, there are 11 common indoor air pollutants, including nitrogen dioxide, formaldehyde, carbon dioxide, respirable suspended particulates, carbon monoxide, ozone, total volatile organic compounds (TVOCs), radon, biological contaminants (fungi and dust mites etc.), mould and environmental tobacco smoke.
Among them, 7 are generated and emitted from combustion (carbon dioxide, nitrogen dioxide, respirable suspended particulates, carbon monoxide, formaldehyde, TVOCs and environmental tobacco smoke). Results showed that 71.4% of the respondents do not know air pollutants will be generated through incomplete combustion process. Apart from the similar examples of generation in vehicle engine exhausts, pollutants, such as, carbon monoxide is also generated through using aroma diffusers and burning candles.

Insufficient knowledge about the source of air pollutants
62.4% of the respondents do not know that pollutants, such as, carbon monoxide, carbon dioxide and TVOCs will be emitted when using aroma diffusers, reflecting a lack of knowledge about this in the general public. Over 70% of the respondents also do not know that ozone will be emitted through using household and office machines, including photocopiers, laser printers and fax machines etc. Ozone is commonly found in daily life. It is also known as “good up high, bad nearby”, because high intensity ground-level ozone will cause irritation to eyes and respiratory system, which may results in asthma, affecting lung function and even the central nervous system.

Unparalleled concern on the health impact of air pollution
WGO conducted a similar survey in 2018. In which, 37% of the respondents think that air pollution had a negative effects on the heart and cardiovascular system. But in this survey, only 15.4% of the respondents think so, composing a huge drop of over 20 percentage point. This reflects that the respondents may have overlooked the negative impact of air pollution on the heart and cardiovascular system.

World Green Organisation (WGO) also found that 96.8% of the respondents agree that air pollution can cause respiratory diseases, while about 70% of them agreed that it can cause skin allergies. Compared with the figure in 2018 (35%), in this survey, more respondents, 53.2% of them (with 50 percent point increase), agree that it has a negative impact on vision health, showing that the public is more concerned about the impact of air pollution on eye diseases. In fact, exposure to respirable suspended particulates, sulphur oxide and nitrogen dioxide in the air may irritate the eyes and make the cornea and conjunctiva dry and uncomfortable, which may even lead to conjunctivitis and Keratitis.

Dr William Yu, Chief Executive Officer of the World Green Organisation, said: “The results this year shows that the public’s perception featured with “three low, one high”. Their awareness is LOW on the pollution sources (vehicle engines, aroma diffusers or candles, photocopiers, laser printers), the generation process (mostly emitted through combustion) and the output – air pollutants (11 common indoor air pollutants). They may HIGHLY overlook the risk of air pollution on heart diseases as they are only concerned about the risk on respiratory system and less concerned that the heart may also be threatened by air pollutants, especially heavy metal.“

Establish an indoor air quality monitoring system to safeguard public health
The World Health Organisation (WHO) has included “indoor air pollution” as one of the top 10 threats to global health. According to different researches, exposure to indoor air pollution almost doubles the risk of pneumonia in children. It’s also one of the risk factors of acute lower respiratory tract infection in adults. Besides, it also increases the risk of heart diseases, chronic obstructive pulmonary diseases and even lung cancer.

In order to improve indoor air quality, nearly 90% of the respondents will open the windows more often to increase ventilation, while almost 60% of them will clean the ventilation system including air filter and ducting regularly. Almost 70% of them will keep their premises clean and dry by vacuuming regularly and cleaning up mould. Other than that, 33.2% of the respondents will use air purifiers to improve indoor air quality.

Dr. Horace K.W. Mui, Associate Head and Associate Professor in the Department of Building Services Engineering of The Hong Kong Polytechnic University, said: “We need an indoor air quality monitoring system in Hong Kong to safeguard our health and comfort.” Dr Mui is currently working on the project of a real time IAQ sensor, which can manage the indoor air quality (IAQ) through big data and AI in a more cost effective approach. He will also offer valuable advice on the development of indoor air quality monitoring system in Hong Kong.

Ways to improve indoor air quality in daily life
In order to improve indoor air quality, WGO suggests that Hong Kong citizen can consider the following measures: purchase air purifiers with the filtering particulate matter function. Avoid using paint or furniture that contains harmful organic compounds. Avoid using carpets, or at least keep the carpets and ventilation equipment clean. Avoid using products that require burning. Choose efficient and energy-saving stoves, range hoods and ventilating fans to reduce the amount of particulate matter produced or accumulated.

In conclusion, WGO hopes that the public has a deeper understanding of the sources, the types and the generation process as well as the health impact of indoor air pollution. Everyone should also pay more attention to the household and office equipment, in order to reduce indoor air pollutants at sources.

World Green Organisation
The World Green Organisation (WGO) is an independent non-governmental organisation which focuses on environmental and social issues. Through science-based policy researches and community projects, the WGO aims at enhancing the quality of the environment, promoting a greener economy, and improving people’s livelihood. In particular, it focuses on the social concern of the underprivileged in order to help realise its vision of sustainable development. For more information, please visit http://www.thewgo.org/

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