Singapore's Performance for PM2.5, PM10, Sulphur Dioxide, Ozone, Nitrogen Dioxide and Carbon Monoxide Emissions

10 Ms He Ting Ru asked the Minister for Sustainability and the Environment (a) how did Singapore perform in 2021 and 2022 for PM2.5, PM10, sulphur dioxide, ozone, nitrogen dioxide and carbon monoxide emissions respectively; (b) whether the Government has conducted any review of the failure to meet the 2020 air quality targets; (c) whether there are any updates to Singapore’s long-term air quality targets; and (d) whether there are new plans being developed to meet the long-term targets and, if so, what are they.

The Minister for Sustainability and the Environment (Ms Grace Fu Hai Yien): Mr Deputy Speaker, the concentrations of the key air pollutants in 2021 and 2022 are available on the Department of Statistics website, singstat.gov.sg. Information on air quality is also available through the Key Environmental Statistics published annually by my Ministry.

In 2021 and 2022, Singapore's air quality was in the "Good" or "Moderate" range 99.5% and 100% of the days, respectively. Singapore has met the 2020 air quality targets for nitrogen dioxide, carbon monoxide, sulphur dioxide and fine particulate matter PM_2.5. PM₁₀ and ozone continue to be a challenge due to multiple factors, including the weather and complex chemical reactions between the pollutants and the environment – that refers to ozone.

We will continue to review our air quality targets as well as policies to address local pollutant emissions. For example, the emission standards for motorcycles and existing industrial plants were further tightened this year.

Mr Deputy Speaker: Ms He? No questions? Dr Tan Wu Meng.

Dr Tan Wu Meng (Jurong): I thank the Minister for her answer. I declare that I am a medical doctor at a public hospital looking after cancer patients. I would like to ask the Minister one supplementary question.

On 6 April 2023, the cover story for the international scientific journal, Nature, looked at the correlation between air pollution and lung cancer in non-smokers. In that journal, an article was published suggesting that PM_2.5 levels could contribute to an increased lung cancer risk in people who are non-smokers or never smokers.

The contribution, of course, was much less than what you get from smoking, but it was nevertheless notable and it made the front page of this international scientific journal. Would the Ministry consider looking at the PM_2.5 target levels, given the emerging scientific evidence and to see whether we can bring the PM_2.5 levels even lower as time goes by, as the science evolves and our understanding of the contribution of pollution to health and disease evolves as well.

Ms Grace Fu Hai Yien: Deputy Speaker, please allow me to address the supplementary question from Member Dr Tan. First of all, I would like to reiterate that our air quality for 2021 and 2022 both met the 2020 air quality targets for PM_2.5. So, that is an assurance to Dr Tan. And also, I would like to point out that for most of the medical studies, as far as I am advised by my colleagues, are dependent on the length of the exposure as well as the concentration of exposure.

So, we have to apply those underlying conditions and look at whether they are relevant to the Singapore context. As I have mentioned, we have met the PM_2.5 quality targets and, therefore, we do not have a prolonged over concentration or exposure to PM_2.5 in Singapore.

Having said that, I think the suggestion to review our targets continually, given new information coming from the medical and health scientific communities, is the right one. And this is what we have been doing and we will continue to do so.