This year, the government has urged people not to leave the house on certain days due to poor air quality. However, overall they claim the conditions are not so bad and not all the pollutants are locally generated
About two or three years ago, Gil (not his real name) went to the hospital with a persistent cold and cough. The doctors told him it was an asthma attack, a condition he has suffered from for a long time.
“I found it strange because I had never had this particular problem before,” he says.
One day during a typhoon he suffered an attack so acute he had to go to the hospital to get oxygen. Gil’s story is not unique.
“The same thing happened to a family member two years ago, who arrived here and had a strong allergic attack,” he recalls. They also ended up having to go to hospital to get oxygen treatment.
Similar stories can be heard in cafes around town, of other people who have also been affected. Many are suspicious that their conditions are due to poor air quality. There are no specific diagnoses to confirm their suspicions, but experts warn: air pollution causes health problems.
Gil was eventually prescribed medication, to use in the event of another attack, in addition to wearing a protective mask.
In an email response to CLOSER, the Association of Macau Portuguese Speaking Physicians (AMLPM) indicated that in Macau, “there is no clinical evidence or studies to confirm the link between pollution and increased use of health care emergency or specialty consultations.” Instead, they suggest that it is the patients themselves who end up making the association between their poor health and pollutants.
AMLPM does however admit that in certain areas of Macau, “with little ventilation and higher concentrations of traffic and during times of certain climatic conditions,” residents may feel “a certain degree of eye irritation, difficulty breathing, coughing and malaise among other symptoms, especially if the exposure is over a longer period.”
Given that “contaminated air is a major inducer of health effects in humans, animals, plants, microorganisms or other living matter,” the World Health Organization (WHO) reports that the serious health risks are not only related to exposure to respirable suspended particulate matter (known as PM) but also to ozone, nitrogen dioxide and sulfur dioxide.
“Ozone is an important factor in morbidity and mortality from asthma, while nitrogen dioxide and sulfur dioxide may also play a role in asthma, bronchial symptoms, pulmonary inflammation and reduced lung function,” explains AMLPM. “Those who live in large urban centres are most affected by air pollution. And on days with low humidity or temperature inversion, the problem increases”.
Among the most harmful agents for health are the suspended particles with a radius of less than or equal to ten micrometers (PM10) that “can penetrate and become lodged within the lungs.” Persistent exposure can result in “the development of cardiovascular and respiratory diseases as well as lung cancer.” Because of the size, and being composed of sulfate, nitrate, ammonia, sodium chloride, black carbon, mineral powder and water, these are the particles that “affect people the most,” the AMLPM response details.
WHO indicates that there is a close and quantitative association between exposure to high concentrations of PM and an increase in mortality or morbidity over time. Thus, by reducing PM10 from 70 to 20 micrograms per cubic meter, deaths related to air pollution can be decreased by about 15 percent.
WHO estimates that about 80 percent of premature deaths related to air pollution are linked to ischemic heart disease (reduced blood supply to the heart) and strokes, while 14 percent of deaths result from chronic obstructive pulmonary disease or acute respiratory infections, and six percent are due to lung cancer.
“For example, both smoking and air pollution contribute to the occurrence of lung cancer. Some deaths from lung cancer could be avoided if there was an improvement in air quality and reduced tobacco consumption,” AMLPM states in their response.
According to a report by WHO in 2014, there were seven million deaths worldwide in 2012 linked to pollution. In the short term, the symptoms that can usually be associated with “the sporadic or persistent contact with these types of pollutants” range from “burning eyes, itchy nose or throat irritation, and may even trigger rhinitis and asthma attacks in patients with an immunoallergic history. This may result in conjunctivitis, rhinitis, pharyngitis, tracheitis, bronchitis and alveolitis”.
“However, people who have spent a number of years exposed to environments of atmospheric pollution are more prone to develop pulmonary, cardiovascular and dermal complications, develop chronic obstructive pulmonary disease, asthma and bronchitis and can be more susceptible to respiratory cancer,” AMLPM says.
The 2013 International Agency for Research on Cancer (IARC) evaluation concluded that air pollution is carcinogenic to humans, with the component of air pollution particles most associated with cancer – polycyclic aromatic hydrocarbons – especially linked to lung cancer. ICRA also linked air pollution to increased urinary tract cancer.
The ICRA evaluation also concluded that air pollution in cities and rural areas resulted in 3.7 million premature deaths per year worldwide in 2012. This mortality was due to exposure to PM10.
– Sensitive Groups –
Overall, children are “more sensitive than adults to any form of air pollution” and growing up in “very affected” places, they have “more difficulty breathing, a lower lung capacity and are more likely to develop respiratory disorder diseases.”
Other particularly affected groups are individuals who already have “lung diseases or people who are immuno sensitive to various allergens (allergic) asthma sufferers and those with chronic obstructive pulmonary disease.” The elderly are also at increased risk.
Therefore, says AMLPM, given the population density of the territory, the increasing numbers of vehicles and a weak green urban density, there is “potential risk of harmful effects to the health of residents and also to the millions of people who visit.”
Noting that Macau does not suffer from “dangerous limits of outdoor pollution,” compared to some cities in Asia or America, AMLPM nonetheless states that pollution in the city is “a major problem at a local level.” But it is important to realize that “some of the pollutants sensed here” originate thousands of kilometres away.
When asked whether they have data on the number of patients who were admitted to hospitals in the territory with symptoms of diseases probably related to air quality, the Health Services official source replied by email: “Some diseases may be related to air pollution, but there are many other factors that may have contributed to their appearance. The increase or decrease in the incidence of certain diseases cannot be considered a result of the deterioration or improvement of pollution levels in the air.”
– Nothing alarming –
Over the past decade, air quality has remained more or less stable, says the director of the Macao Meteorological and Geophysical Bureau (SMG). It’s not great, but it is not as bad as in Mainland China, Fong Soi Kun guarantees. In Macau, the monitoring of air quality is based on the analysis of six pollutants: the respirable suspended particles with a radius less than or equal to ten micrometers (PM10); suspended fine particles with a radius equal to or less than 2.5 microns (PM2.5); and carbon monoxide; nitrogen dioxide; ozone and sulfur dioxide.
In the territory, SMG only started recording PM2.5 levels in 2013, meaning that it’s still “too early” to make an analysis of the change. “But PM10 has remained more or less the same,” Fong says.
With respect to sulfur dioxide, the figures show that it has been “improving a lot,” especially since 2003, after the government limited the sulfur content in diesel fuel for vehicles, determining that it could not exceed 0.05 percent in weight. “One sees the impact clearly,” the director adds.
Nitrogen dioxide has remained stable over the last 10 years, with the only agent to increase slightly being ozone.
“This is a phenomenon across the region,” Fong affirms.
Carbon monoxide levels are improving, especially on the streets. “We have limited the use of twin cylinder motorcycles and there has been great improvement.”
Looking at the data from the last ten years, air quality index levels that are considered unhealthy are usually recorded in autumn and winter, although it can also happen in summer, during typhoon season.
“It is a phenomenon that exists – the air enters the lower atmosphere and then develops vertically, when it reaches the upper atmosphere it breaks up. We are affected by the winds [caused by typhoons, in Taiwan or China] – so the wind rises and falls in Macau, causing a greenhouse effect and limiting the quality of the air released and cannot mix in the atmosphere,” explains Fong.
When the situation is triggered by typhoons, Fong Soi Kun clarifies that it is “almost impossible to control,” even though the public can protect themselves by staying at home more. “On days of poor air quality, citizens do less exercise, and spend more time indoors, since generally the quality indoors is better than outside.”
The Director of SMG states that, even without typhoons nearby, there are days when the air quality is unhealthy, but it is not necessary to panic. According to the information available on the SMG website, if the index is between 0 and 50, it means that the air quality is good, if it is between 51 and 100 it is moderate, and between 101-200 is unhealthy. More than this is considered very unhealthy. When the index is above 100 it indicates that human health is affected.
“In Macau, it never reaches above 300 and 400, it has only reached 200 and that was a few years ago; here it usually only reaches just over 100,” he assures.
In cases where the index is between 100 and 200, “it affects elderly people with breathing or heart problems. For example, people suffering from lung diseases may find it hard to breathe,” he says. Of course, if the air quality remains above the 100 index for “prolonged” periods it may cause asthma in a supposedly healthy person. “But this usually does not happen in Macau.”
Fong Soi Kun notes that some steps taken by the local government are having a positive impact on air quality. Moreover, measures should be taken at regional level.
So, even compared, for example, with neighbouring Hong Kong – which often has warnings regarding the air quality – Fong Soi Kun emphasizes that Macau does not suffer as much.
“We don’t have so many tall and closed buildings such as Hong Kong, so the air circulation is better. We are also one of the smallest cities in China.”
Up to June 2015, on most days the air quality remained below the 100 level on the index.
“Carbon monoxide levels are generally good. This is the result of restrictions on twin cylinder motorcycles,” he says, adding: “Ozone is the worst, around 50, but ozone is a regional pollutant, transformed by solar radiation.”
The worst month was February, mainly due to weather conditions.
“The wind blew from the north bringing Mainland pollutants to Macau.”
The levels and effects of PM2.5 in the territory are still to be determined, but a detailed study throughout Guangdong Province is under way in order to know where the particles originated.
