Tag: MSE

Project Wolbachia Mosquitoes

In Parliament on 3 Feb 2026, I raised concerns about mosquito biting reports I received from several Hougang residents following the local release of mosquitoes under Project Wolbachia. One resident even showed me the bites on her daughter and samples of mosquitoes she had collected to prove the extent of the problem. While it is my understanding that male mosquitoes do not bite, the evidence from my constituents could not be ignored.

The Minister for Sustainability and the Environment explained that the sorting process is 99.9% accurate and that no reports of bites from male Wolbachia mosquitoes have been received. It is likely that any bites come from existing local female mosquitoes or the tiny fraction of female Wolbachia mosquitoes that occasionally slip through the sorting system.

It is reassuring to know that this technology remains a safe and powerful tool that has already slashed dengue risk by over 70% in some areas. I fully support these innovative efforts to keep our community safe from disease and I will continue to work with the authorities to address any feedback from the ground.

This is the full question and answer:

Error Rate In Sex-Sorting Process For Mosquitoes In Project Wolbachia And Process To Ensure These Mosquitoes Lack Physiological Capability To Bite Humans


Mr Gerald Giam Yean Song asked the Minister for Sustainability and the Environment (a) how many reports of biting by male Wolbachia mosquitoes have been received since 2024; (b) what is the current error rate for the sex-sorting process for Project Wolbachia; and (c) what scientific evidence ensures that these released male mosquitoes lack the physiological capability to bite or draw blood from humans.


Ms Grace Fu Hai Yien: We have not received any report of biting by male Wolbachia mosquitoes. Residents in Project Wolbachia sites may still experience mosquito bites from female mosquitoes of species that are found locally, including those not released by Project Wolbachia. Source reduction efforts, therefore, remain important in suppressing the mosquito population.


Through our rigorous laboratory studies and quality control checks, we found that the sex-sorting process for Project Wolbachia achieved an accuracy of 99.9% The small number of female Wolbachia mosquitoes inadvertently released is negligible compared to the overall mosquito population in the community, and these females have significantly reduced ability to transmit diseases. Neighbourhoods where male Wolbachia mosquitoes have been released have seen an 80% reduction in female Aedes aegypti mosquito populations and more than 70% reduction in dengue risk.


NEA has thoroughly studied the Wolbachia-Aedes suppression technology and conducted independent risk assessments, concluding that it is safe and poses no risk to human health. This conclusion is supported by international research and independent reviews.


Source: Singapore Parliament Reports (Hansard)

Midge Situation at Bedok Reservoir


In Parliament on 12 Feb 2026, I raised concerns about the growing midge population at Bedok Reservoir after hearing from many of my residents. Since November 2025, many residents have faced issues with these pests in their homes. I asked the Minister if the midges are becoming resistant to our current biological larvicides and whether PUB should rotate its chemical controls. I also wanted to know how effective those LED spotlights really are at keeping midges away from residential units.


The Minister for Sustainability and the Environment confirmed that midge numbers are indeed higher this year compared to previous ones. She noted that current larvicides are still working well so there are no plans to change them yet. Instead, PUB has increased fogging and the use of larvicide while using LED lights to trap midges for more targeted treatment.


I understand that the situation remains a challenge for many families living nearby. I will continue work with PUB to explore more effective ways to manage these outbreaks so our daily lives are not disrupted.


This is the full question and answer:


Midge Population at Bedok Reservoir and Effectiveness of Control Measures


Mr Gerald Giam Yean Song asked the Minister for Sustainability and the Environment (a) whether the midge population at Bedok Reservoir from since November 2025 is larger compared to previous years; (b) whether studies have been conducted on midge resistance to current biological larvicides; (c) whether there are plans to rotate chemical controls; and (d) what is the measurable effectiveness of LED diversion in reducing midge counts in residential units.


Ms Grace Fu Hai Yien: The midge population at Bedok Reservoir in the period from November 2025 to January 2026 is higher compared to previous years. The Public Utilities Board’s (PUB’s) data shows that the current biological larvicide remains effective. PUB thus does not have plans to rotate its chemical controls.

In response to the higher midge population in this period, PUB has increased the application of biological larvicide and the frequency of fogging. LED spotlights concentrate the midges which allows for more targeted fogging. For this reason, LED spotlights remain a useful part of the suite of measures, even though PUB has not been able to quantify their effectiveness. PUB will continue to monitor the midge situation at our reservoirs closely and review the measures as needed.


Source: Singapore Parliament Reports (Hansard)

MSE: Free or Low-cost Drinking Water

Committee of Supply Debate 2025, Ministry of Sustainability and the Environment

4 March 2025

More restaurants now charge for plain water, and some price bottled water the same as sugary drinks. This nudges consumers towards sugar-laden beverages, increasing the risk of obesity and diabetes.

Free or low-cost drinking water should be made more widely available across F&B outlets, shopping malls, heartland coffeeshops and public spaces. This supports healthier choices and reduces unnecessary costs for consumers.

I urge MSE to encourage and work with F&B outlets, coffeeshops, and malls to provide free or low-cost drinking water as a best practice.

MSE should also promote a culture of carrying reusable water bottles as part of Singapore’s sustainability efforts. Refilling reusable bottles cuts down our reliance on single-use plastics.

By nudging businesses, building owners and the public towards these norms, we can help Singaporeans stay hydrated while making choices that benefit their health, their wallets, and the environment.