HIDDEN IN THE HAZE: THE DANGERS WE INHALE

Disease-Causing Particles That Enter The Lungs Are Getting More Minute

Malathy Iyer | TNN

 When the 'Asian Brown Cloud' was first spotted over the Indian Ocean almost a decade ago, an Indo-French team of scientists, including a few from IIT-Bombay, estimated that India was 6 to 7% darker than it was in 1950 due to greenhouse gas emissions released by the mega-haze. This, they postulated, meant more parasites and insects and, hence, more diseases.
    Back in 2002, the experts felt that the emissions from biofuels—such as cars, trucks and buses (plenty of which are operated in Mumbai) and burnt fossil fuels (such as 'chulas' and coal in rural areas)—had contributed to the rise of brown clouds as also the incidence of respiratory ailments.
    Now, Atmospheric Brown Clouds (ABCs) have returned. The new name has been given after India and China protested against the use of Asian in the nomenclature.
    According to a United Nations Environment Programme report released last week, the world is going to be a sicker place because of ABCs. Soot has been found at a monitoring station near Mount Everest, levels of ozone in the respirable zone are higher than before and heart diseases could rise, the UN team has said.
    Mumbai's doctors are alarmed, but not entirely surprised. When the first-ever study on environmental pollution and its effects on health was done by a team from KEM Hospital, Parel, over a decade ago, the worrisome factor was PM 10. In other words, Particulate Matter (PM) measuring 10 microns was identified as a cause of respiratory illness—chest congestion, bronchitis, allergies and so on—in the city.
    "Now, we are staring at PM 1, which is Particulate Matter that is just a micron thick,'' said Dr Pramod Niphadkar, leading allergy specialist in the city. Mumbai's research scientists have recently found out about ultra-fine-PM and even nano-PM, which is even smaller than 1 micron.
    The smaller the Particulate Matter, the easier it is for it to slip into the lung, bypassing the body's filtering mechanism—the muco-ciliary escalator—which is meant to trap foreign bodies. "We now know that Suspended Particulate Matter causes long-term and irreversible damage to the lungs,'' said a civic hospital doctor.
    With the latest ABC possibly containing diesel Particulate Matter, Mumbaikars can expect worse. "Increased pollution levels could mean more cases of respiratory ailments, allergies, asthma and even heart attacks,'' said Niphadkar.
    Particulate Matter can 'burden' white blood corpuscles, affecting a person's general health. This can lead to clotting in blood vessels connected to the heart and brain, triggering heart attacks, said doctors. "So, what is regularly passed off as a stress-induced heart attack could just be related to pollution,'' said a doctor.
    For smokers, ABCs could spell worse news. "Smokers have damaged lungs because of their 'personal' pollution, but increased pollution could make them more vulnerable to lung cancer,'' said Niphadkar.
    In Mumbai, where diesel is the favoured fuel, PM comprising diesel globules along with allergens makes vulnerable patients 10 times more susceptible to allergy attacks.
    THE ABCs OF ATMOSPHERIC BROWN CLOUDS
    Mumbai is one of the megacities identified as an
    ABC hotspot
    ABCs form due to burning coal, other fossil fuels
    and biomass
COOLING | Globally, ABCs may be countering or 'masking' the warming impacts of climate change by between 20% and 80%, because particles such as sulphates and some organics reflect sunlight back into space and cool the earth's surface. Other particles, like black carbon in soot, absorb sunlight before it reaches the ground. So 'hot spot' cities become darker or dimmer
WARMING | In some cases and regions, ABCs can aggravate the impact of greenhouse-gas-induced climate change because carbon and soot absorb sunlight and heat the air
EFFECTS | Risks to health and food production, dimming light, weakening monsoon, rise in heavy rain days
DANGER | If ABCs were eliminated overnight, it could trigger a rapid global temperature rise of as much as to 2^o Celsius. Thus, there should be a simultaneous cut in greenhouse gases
UN Warning: The Health Risks
ABCs contain a variety of toxic aerosols, carcinogens and particles, including particulate matter of less than 2.5 microns in width (PM 2.5). These have been linked to a variety of ailments, from respiratory diseases to cardio-vascular problems
OUTDOOR EXPOSURE | If there are increases of 20 microgramme/cubic metre in PM 2.5, it could lead to about 3.4 lakh more deaths per year in China and India
Economic losses due to outdoor exposure to ABCrelated PM 2.5 has been crudely estimated at 2.2% the GDP in India and 3.6% the GDP in China
INDOOR EXPOSURE | IThe World Health Organisation estimates that more than 7.8 lakh deaths in the two countries can be linked to solid fuel use at home
Source | UNEP Atmospheric Brown Cloud Report
Atmospheric Brown Clouds Can...
Trigger respiratory ailments such as bronchitis
Scar the lungs forever
Worsen attacks among patients with asthma & allergies
Lead to clots in blood vessels, causing heart attacks
Increase the probability of lung cancer among smokers