By Poyi (Natalie) Leung
The Air Pollution Indices (API) compiled by the Meteorological and Geophysical Bureau (SMG) through the five monitoring stations has shown a reduced number of poor air quality days since 2008. People in Macau were also breathing air with low pollutant concentrations on most days over the past decade.
However, the rapid industrialisation in the Pearl River Delta region and the increasing number of vehicles on Macau’s roads may be quietly threatening the condition of today’s air in the territory.
Travel advice issued by the Australian Department of Foreign Affairs and Trade suggests nationals with existing heart or respiratory illnesses reduce physical exertion and outdoor activities on days when high pollution levels are reported. “The levels of air pollution in Macau may aggravate bronchial, sinus or asthma conditions,” they said.
On March 22, 2010, the API in high density area’s in Macau’s northern district reached as high as 329, which translated into a ‘severe’ level of air quality – just below the top ‘harmful’ level (index between 401 and 500).
On days of ‘bad’ air quality, the SMG says symptoms in people who have cardiac or respiratory disease may become “slightly worse” and they should “reduce physical exercise and outdoor activities”, while healthy people may also experience “discomfort”.
On the other hand, when ‘very bad’, ‘severe’ or ‘harmful’ air quality is detected, the SMG advises people with cardiac or respiratory disease to cut down physical exercise and also avoid staying outdoors as their symptoms “might be obviously affected”. It also said the general public “would experience discomfort”.
The bureau explained to the Macau Daily Times that the poor atmospheric quality on those two particular days was caused mainly by a soaring concentration of respirable suspended particulates, in relation to sandstorms in Mongolia which brought dust to the South China Coast.
In 2009 the University of Macau (UM), Environmental Protection Bureau (DSPA) and SMG jointly conducted a pilot study funded by the Science and Technology Development Fund (FDCT) to monitor air quality in Macau for seven consecutive days between February 18 and 24 using a mobile in-situ platform borrowed from the Hong Kong University of Science and Technology.
The DSPA told the MDTimes that the findings have been used in the special planning for the prevention and treatment of atmospheric pollution. It expected that the second draft of the “Macau Environmental Protection Planning” report will be launched for public consultation in the third quarter of this year.
Besides common air pollutants such as carbon monoxide (CO), sulphur dioxide (SO2), nitrogen dioxide (NO2) and black carbon, the pilot study measured respirable suspended particulates of a size between 10 nanometres and 10 micrometres.
SMG groups the daily measurement of respirable suspended particulates of 10 micrometres or less (PM10) together and does not specify the distribution of the fine particles of different sizes within the range.
According to professor Mok Kai Meng, dean of the UM Honours College who led the 2009 study, the mostly common particulates were those smaller than 2.5 micrometres, which were “very likely” contributed by vehicles.
“It is very important to identify the concentration of fine and ultrafine particles in air as the smaller they are, the easier for them to enter a human body through inhalation and skin absorption,” he said.
Mok stressed that the findings of the study could not fully reflect the overall situation of the quality of air in Macau since data was collected for merely a week, but he is certain that in addition to local contribution, external factors are playing a significant role.
“Air quality in Macau is very much influenced by mainland China,” he told the MDTimes in an interview.
“The changes in the concentration of particles and wind direction are closely related. When the wind was blowing from the north, the concentration level all over Macau suddenly soared and exceeded the standard,” he said.
When a south wind was reported on February 18 2009, air quality in the Macau peninsula deteriorated due to the high concentration of nitrogen dioxide (NO2) mainly from car emissions. Yet two days later the wind changed to blow from the north which consequently pushed air pollution level’s up throughout all of Macau including Taipa and Coloane.
A north wind means that fine particles from the dry land in mainland China will be borne by the wind to Macau, increasing the concentration of PM10 a phenomenon agreed to by SMG.
The SMG told the MDTimes that based on the monitored data since 1999, the main air pollutants in Macau are PM10, O3 and NO2. Yet, PM10 and O3 (ozone) were found to be the pollutants that caused the city’s air quality to reach a ‘bad’ level or above.
While high PM10 concentration is a problem mainly found in autumn and winter, Mok said summer time is troubled by O3 and strong sunlight can cause “a lot of secondary pollution”.
He disclosed that a research proposal on ozone has recently been submitted to FDCT applying for financial support.
In addition, the SMG said it is currently upgrading the apparatus in the five monitoring stations and plans to add the measurement of the PM2.5 concentration in the air in each of the locations.
The monitoring stations are respectively on the roadside in Calçada do Poço Macau, in the high density residential areas in Macau’s northern district and Taipa’s Rua de Tai Lin, at the Big Taipa Hill (SMG premises) as well as in Coloane near the Panda Pavilion.
Call for regional effort
With the continued development in the Pearl River Delta region, air pollution has become a “regional problem” and a part of “growing pains”, the professor described.
“’All pollutants and emissions are a result of industrial or urban development. When high GDP is reported, consumption [of resources] and production increase and more waste will naturally be produced,” Mok said.
“The relationship between economic development and air pollution is absolutely proportional. The point is to try to minimise the [environmental] impact to the lowest level,” he told the MDTimes.
Hence, the professor pointed out that regional cooperation is necessary if the SAR hopes to improve the quality of air effectively.
“It’s not the work of only one place. Even if Macau cut its emissions to the lowest level, air quality wouldn’t necessarily be enhanced completely,” Mok said, “but of course it’s still Macau’s responsibility to improve its own environment first of all.”
According to the SMG data between 2006 and 2010, a majority of the days reported ‘good’ or ‘moderate’ levels of air quality, respectively at 91, 90, 95, 99 and 98 percent.
Mok deemed that the current air condition in Macau is not as serious as in neighbouring Hong Kong, but has become “more polluted” when compared to a decade ago.
Nevertheless, the higher number of days in which ‘bad’, ‘very bad’ or even ‘severe’ air quality was recorded particularly in autumn and winter has raised the professor’s concern.
According to the Environmental Protection Bureau (DSPA), atmospheric pollution has become an “important agenda” in the Pearl River Delta. The special Guangdong-Macau working group set up in 2007 has been exchanging air quality monitoring data and analysis regularly in a bid to “understand the situation in the region and implement joint research”.
The DSPA also told the MDTimes that cooperation, information exchange and liaison mechanisms with other neighbouring governments in the mainland have been reinforced through different agreements and development plans in recent years.
According to Mok, vehicles are undeniably the major source of air pollution within Macau, where an industrial sector basically “doesn’t exist”.
The 2009 study showed that emissions from trucks and scooters were particularly worrying. “Vehicle emission control is needed and regulations are also necessary to limit the number of cars on the road such as raising related taxes,” he said.
He pointed out that at the same time the government should ensure that a highly efficient and good quality public transportation system is in place to lure local people to forego using their own cars.
“I believe that if public transportation can satisfy people’s needs they would be willing to shift to buses and taxis,” he said.
The light rail transit, he added, should ease the city’s traffic pressure to a certain extent.
Yet the professor believes that emission control must be imposed on public transportation, tourist coaches and casino courtesy coaches in the first instance as “they spend a long period of time on the road each day”.
The new service contracts that will come into effect on August 1 required the three public bus operators to purchase new buses that meet the Euro 3 emission standard. “We’re aware that some of the new vehicles even comply with the Euro 4 standard”, the spokesperson added.
On the other hand, the DSPA agreed that exhaust emissions are one of Macau’s main sources of air pollution and said short, mid and long-term measures have been identified to tackle the issue.
The draft of the administrative regulation to tighten exhaust emissions standards in newly imported automobiles is complete and entered the legislative process. The regulation proposes adhering to Euro 4 standards.
The DSPA will also implement emission standard research of existing vehicles in Macau this year and are attempting to complete the draft in 2012.
Electric car alert
The Macau Government is mulling the wider use of electric cars in the territory. However the professor warned that despite these cars produce fewer emissions, a tougher problem could be waiting for the government ahead.
“Waste batteries can cause other pollution which may stay with you forever [because] conventions are in place that forbid Macau from exporting toxic waste to any other places,” Mok said.
“They will have a long-term impact on Macau unless there is policy outlining how they can be handled and recycled locally,” he added.
In addition, he pointed out that whether or not local people can afford high battery recycling costs is also another issue that needs to be considered.
“The use of electric cars requires a very thorough and long-term plan and the focus can’t be put only on the air quality issue. Everything has its pros and cons but the most important is [Macau] can choose the one that suits the city and doesn’t follow others blindly,” the professor stressed.
Looking to the near future, Mok told the MDTimes he doesn’t believe that Macau’s air quality will be improved “drastically” when the economy continues to grow, “unless there are very rigorous regulations in place”.
Yet he pointed out that tough environmental control may then slow down the city’s development and so, “it’s always a hard decision for the developing countries at all times”.
Nevertheless if the current development pace continues in the Pearl River Delta and Macau, Mok expected that “adverse effects” will be the result and “air quality will deteriorate”.
Apart from strategies proposed against atmospheric pollution generated by traffic, the DSPA said it will implement a study on stationary source emissions and formulate a related list of emission standards between 2011 and 2012, adding that the first phase will target the “high-pollution industrial establishments”.
The latest official statistics showed that the DSPA received 357 air pollution complaints in 2010, a surge of 119 percent year-on-year. They mainly concerned grease, odour and smoke emitted by restaurant ventilation systems.
The bureau told the MDTimes an investigation was launched last year by the Macau Development and Quality Research Institute aimed at proposing technical suggestions to local small and medium eateries and restaurants to improve emissions.