By Roger Teoh
Health studies show that a prolonged exposure to vehicle-emitted pollutants greatly increases the risk of various heart and lung diseases and early death.
Background air pollution levels published in the Environmental Impact Assessement (EIA) do not appear to be reasonable.
Air quality modelling results are likely underreported to comply with the Malaysia Ambient Air Quality Standard (MAAQS).
The proposal to construct a new six-lane highway in Penang (Pan Island Link expressway, PIL 1) has sparked a healthy debate on the plan’s effectiveness, financial cost and adverse environmental impact.
Recently, the Environmental Impact Assessment (EIA) for parts of the Penang Transport Master Plan (PTMP) was made available by the Penang state government for public scrutiny.
While credit should be given to the Penang state government for releasing these documents online to improve transparency, this article will critically analyse these published results, focusing on air quality and human health to further understand the adverse environmental and social impacts of the six-lane highway.
Health effects of pollution from vehicles
The transport sector is a major contributor to greenhouse gas emissions and air pollution in urban cities. A wide body of academic research has unanimously shown an elevated concentration of pollutants such as nitrogen oxides (NOx), particulate matter (PM), carbon monoxide (CO) and sulphur dioxide (SO2) near major highways and congested city roads.
Most of these pollutants are released from vehicle exhaust (due to incomplete combustion), and from brake and tyre wear.
Despite ongoing improvements in engine technology, the adverse environmental and health impacts of pollution from vehicles remain significant. For example, particles emitted in the exhaust of a vehicle get increasingly smaller in size as combustion efficiency improves.
Although not visible to the naked eye, these ultrafine particles are more likely to penetrate deeper into the lungs and subsequently enter the blood circulation system and internal organs.
Recent health studies have shown that prolonged exposure to vehicle-emitted pollutants greatly increases the risk of heart and lung diseases, contributing to early death.
The PTMP in its present form places heavy emphasis on vehicular traffic and excessive highway construction. Without a doubt, this will increase the number of cars on the road and worsen Penang’s air quality.
While the recent EIA report suggested that air quality and human health impacts from the construction and operation of the six-lane PIL 1 highway are insignificant, this could be an underestimation, as will be highlighted in this article.
Dubious air quality measurement results
While background concentrations of PM10, PM2.5, NO2 and CO were measured and published in the EIA of the highway, we can very confidently suggest that some of the reported results are incorrect and unrealistic.
For example, 10 of the 12 air quality monitoring stations reported negligible nitrogen dioxide (NO2) concentrations of less than 1 µg/m3 (microgrammes per cubic metre air). Such values do not make logical sense.
To give the public a better understanding and perspective of a realistic range of NO2 values in a city, we will use the modelled annual average NO2 concentrations in London as a case study. Data from the London Air Quality Network clearly showed that Central London (with heavy road traffic) and major roads leading to the city typically has higher than 40 µg/m3 of background nitrogen oxide.
Remember, only 39% of Londoners use cars as compared to 96.8% of Penangites. In fact, London has also implemented the world’s largest low emissions zone since 2008, where certain vehicles that fail to meet the minimum emissions criteria are restricted from entering the city.
If the outskirts of London (with lower traffic) still manage to record an annual average NO2 concentration that is more than 15 µg/m3, how is it possible that Penang is able to achieve a concentration level of lower than 1 µg/m3, which is 93% lower than outer London?
Looking closer to home, even the hourly averaged background NO2 concentrations in the Kuala Lumpur metropolitan area ranged between 18 µg/m3 and 94 µg/m3.
Hence, given the London and KL examples, the reported background NO2 concentrations in the EIA for the Pan Island Link highway certainly cannot be trusted.
What’s more, the EIA also reported background PM10 concentrations ranging from 39 µg/m3 to 65 µg/m3. However, any PM10 value above 50 µg/m3 cannot be classified as “good”, as claimed in the executive summary of the EIA.
Such values exceed the recommended guidelines by the World Health Organisation (WHO) and the EU Directive on Air Quality (2008/50/EU), which state that safe levels of PM10 concentrations (24-hour mean) should not exceed 50 µg/m3.
Although current background PM10 levels in Penang are technically in compliance with the current MAAQS, these air quality guidelines will get more stringent over time.
Therefore, the expected tightening of air quality regulations in Malaysia must also be considered if the PTMP is really a “long-term solution” as claimed by SRS Consortium. We cannot assume that background NO2 and PM levels near the proposed highway will continue to comply with future Malaysian air quality standards.
More vehicles on the road will increase the background levels of NO2 and PM when the new highway is operational. While we acknowledge that simulation work has been carried out in the EIA to estimate the increase in pollution from the highway, the methodology of the air quality assessment makes highly questionable assumptions.
For example, model inputs were oversimplified where background levels of NO2, PM2.5 and CO are assumed to be zero. Given that background pollutants along the proposed highway route were measured as discussed earlier, why are these values not included into the air quality model?
To make matters worse, the air quality assessment only includes modelling for traffic flowing smoothly (i.e. without congestion) around highway interchange areas. In reality, vehicles are likely to experience congestion as they exit the high-capacity highway back into local urban roads. The pollutants emitted along a congested road are usually higher than when traffic is flowing smoothly.
Based on these two factors, the projected air quality results could be underreported and may even exceed the MAAQS. If background pollution levels and congestion are included in the air quality model, the estimated pollution levels could very likely be higher than reported in the EIA.
Prioritise more sustainable transport modes
Governments in the developed world are now focusing more and more on improving air quality in cities. In fact, most European cities are emphasising on sustainable transport modes and pedestrianising streets in city centres in an attempt to comply with the EU Air Quality Directive (2008/50/EU).
Yet, Penang continues to focus on the old way of prioritising vehicles and building more highways. This is despite the overwhelming scientific evidence pointing out that building more roads not only fails to resolve traffic congestion, but also worsens air quality and human health in cities.
It is also appalling to learn that alternative mass transit options along a route similar to the proposed highway were not even considered in the EIA. What is with the rush to approve Penang’s biggest road infrastructure project to date when alternative options are not even considered?
Roger Teoh is a PhD postgraduate studying at the Centre for Transport Studies, Imperial College London. The opinion of the author is expressed from a neutral standpoint and he is not a member or affiliate of any political party in Malaysia.
The views expressed here are those of the author and do not necessarily reflect those of FMT.