Thread: Bangkok to test run air purifying tower on 8th October

how strange.

when you compare the readings from the air4thai.pcd.go.th government website that has most bkk readings as below 50 and healthy, yet the readings from the independent aqi website taken at the same time have most readings well above 50 and some over 100.


What is PM2.5 and Why You Should Care

PM2.5 readings are often included in air quality reports from environmental authorities and companies. Find out what they mean and why you should monitor their levels.

PM2.5 refers to atmospheric particulate matter (PM) that have a diameter of less than 2.5 micrometers, which is about 3% the diameter of a human hair.

Commonly written as PM2.5, particles in this category are so small that they can only be detected with an electron microscope. They are even smaller than their counterparts PM10, which are particles that are 10 micrometres or less, and are also called fine particles.

Where Do PM2.5 Come From and How Big is Particulate Matter 2.5

Fine particles can come from various sources. They include power plants, motor vehicles, airplanes, residential wood burning, forest fires, agricultural burning, volcanic eruptions and dust storms.

Some are emitted directly into the air, while others are formed when gases and particles interact with one another in the atmosphere.

For instance, gaseous sulfur dioxide emitted from power plants reacts with oxygen and water droplets in the air to form sulfuric acid as a secondary particle.

Why Are PM2.5 Dangerous
What is PM2.5




Since they are so small and light, fine particles tend to stay longer in the air than heavier particles. This increases the chances of humans and animals inhaling them into the bodies. Owing to their minute size, particles smaller than 2.5 micrometers are able to bypass the nose and throat and penetrate deep into the lungs and some may even enter the circulatory system.

Studies have found a close link between exposure to fine particles and premature death from heart and lung disease. Fine particles are also known to trigger or worsen chronic disease such as asthma, heart attack, bronchitis and other respiratory problems.

A study published in the Journal of the American Medical Association suggests that long-term exposure to PM2.5 may lead to plaque deposits in arteries, causing vascular inflammation and a hardening of the arteries which can eventually lead to heart attack and stroke. Scientists in the study estimated that for every 10 micrograms per cubic meter (μg/m3) increase in fine particulate air pollution, there is an associated 4%, 6% and 8% increased risk of all-cause, cardiopulmonary and lung cancer mortality, respectively.

The American Heart Association has also warned about the impact of PM2.5 on heart health and mortality:

“Exposure to PM <2.5 μm in diameter (PM2.5) over a few hours to weeks can trigger cardiovascular disease-related mortality and nonfatal events; longer-term exposure (eg, a few years) increases the risk for cardiovascular mortality to an even greater extent than exposures over a few days and reduces life expectancy within more highly exposed segments of the population by several months to a few years.”

An association between mothers’ exposure to fine particles and birth defects has also been established by several reports.

Children, older adults and those who are suffering from lung and/or heart disease are especially vulnerable to the adverse effects of fine particles in the air and should take special precautions when ambient PM2.5 crosses unhealthy levels.

Click here for more health effects of fine particles.

How to Read PM2.5 Readings









Due to the many adverse effects fine particles can inflict on a large number of people, PM2.5 is one of the major pollutants closely monitored by health authorities around the world. You will most likely come across a dedicated column for PM2.5 alongside the Air Quality Index (AQI), Pollutants Standards Index (PSI) or the air quality standards adopted by your country.

On a very clear and non-hazy day, the PM2.5 concentration can be as low as 5 μg/m3 or below. The 24-hour concentration of PM2.5 is considered unhealthy when it rises above 35.4 μg/m3.

Why 24-hour and not a shorter duration when evaluating the health impact of fine particles? This is because the potential damage caused by air pollutants depends not just on the concentration, but also on the duration of exposure. The longer you are exposed to PM2.5, the higher the risk of developing adverse effects caused by the exposure. That’s why a 24-hour measurement is a better reflection of the health effects of fine particles than say a three-hour reading.

The table below will give you a sense of what levels of PM2.5 are harmful and the appropriate precautions you need to take. It is based on the air quality standards for particle pollution published by the U.S. Environmental Protection Agency.

24-Hour PM2.5 Levels (μg/m3)


Source: U.S. Environmental Protection Agency

How to Protect Yourself Against PM2.5


When the amount of PM2.5 is at unhealthy level, take these steps to reduce exposure and protect your health:

Stay indoor and close all windows and openings that allow polluted air to enter, when possible.
Turn on an air purifier that is equipped with a HEPA filter. Only a HEPA filter can effectively remove fine particles from the air.

Most air filters in air conditioners are not HEPA filters as the latter will reduce air intake and would require the motor to work harder to push / pull air through. But an air conditioner is still helpful when fresh air intake is limited as it helps to circulate air and cool down (or warm up) room temperature.
When most or all windows are closed, do not burn candle, incense or operate devices that emit smoke or gas to prevent harmful particles and gas (such as carbon monoxide) from building up.
If you are a road warrior who must drive in all weather conditions, get a real air purifier for your car that comes with at least HEPA and activated carbon filters. A normal car filter can’t even remove traffic exhaust properly, let alone microscopic particles.

If the air pollution is expected to last for many days, consider moving to an unaffected location.
Boost your body’s resistance against PM2.5 by increasing your intake of these nutrients.
If you must go outdoor, make it short and quick, and wear a N95 or higher face mask.

ADVICE FROM THAI HERBALISTS

Meanwhile, the Department for Development of Thai Traditional and Alternative Medicine (DTAM) has held a seminar on healthcare practices preventing illnesses from PM 2.5 dust. In this seminar, a pharmacist from Chao Phraya Aphaiphubet Hospital Pakakrong Kwankhao said the consumption of some herbs such as Indian gooseberry and tumeric can help fight symptoms caused by PM 2.5 dust, while little ironweed can help improve lungs functionality; infused water from boiling laurel clockvine leaves can have detoxification properties but should not be consumed continuously for more than a month due to high cadmium content; as well as fresh green chiretta leaves which can help with common cold and alleviate inflammation and sore throat, but should be consumed only every 6-8 hours, with extra cautions for persons with cholecystitis.

ADVICE FROM WESTERN SCIENTISTS

Nutrients That Reduce the Negative Effects of PM2.5 Pollution

Intake of essential micronutrients such as B vitamins and omega-3 polyunsaturated fatty acids have been found to reduce the harmful effects of air pollution

According to a report by the World Health Organization, ambient fine particulate matter (i.e. PM2.5) pollution caused some 3 million premature deaths worldwide, making it one of the most deadliest environmental toxins.

Even at levels below regulatory levels, associations of PM2.5 exposure with increased cardiovascular and mortality risk have been found in sensitive individuals including the elderly, and those suffering from asthma, diabetes and cardiovascular disease.

At the individual level, besides installing appropriate air cleaning devices in our working and living spaces and wearing protective mask when necessary, we can also protect ourselves through a healthy diet and smart use of supplements.

Research has found that some nutrients can indeed help to boost our resistance to inhaled environmental pollutants and reduce or neutralize their negative health effects. Below we highlight 3 prominent ones you can use to fight against air pollutants.

Fish Oil
Some evidence suggests that exposure to ambient PM2.5 can lead to a decrease in heart rate variability among susceptible populations (1, 2, 3). Heart rate variability (HRV) is a measurement of the variation in time of successive heart beats. Generally, less variability is an indicator of body stress and diseases. Several studies have also associated reduced HRV with higher risk of cardiovascular events and all-cause death (4, 5, 6).

There are studies suggesting that omega-3 polyunsaturated fatty acids from fish oil may help to blunt the negative effects of PM2.5 on HRV in elderly adults.

In a randomized controlled trial in Mexico City, 50 elderly residents of a nursing home were supplemented with 2 g per day of either fish oil or soy oil for five months (7). In the soy oil group, the high frequency component of heart rate variability (HF-HRV) was decreased by 54% per one standard deviation increase in indoor PM2.5, while only a 7% decrease in HF-HRV was observed after supplementing with fish oil.

Another study compared the effects of supplementing with fish oil against olive oil (3 g/day for four weeks) on healthy middle aged participants who were exposed to either filtered air or concentrated ambient fine particles for 2 hours (8). Cardiac responses were assessed by comparing HRV and electrocardiographic repolarization changes measured before, immediately after, and 20-hour after exposure. Changes in plasma lipids were also evaluated. The study found that omega-3 fatty acids protected against the adverse cardiac and lipid effects associated with air pollution exposure, while olive oil offered little to no protection.

The effects of omega-3 fatty acid on the oxidative response induced by exposure to PM2.5 was also investigated in another elderly population from Mexico City (9).

Inhaled air pollutants, such as PM2.5, can react with antioxidants found in the respiratory tract lining fluids (RTLFs) such as reduced glutathione (GSH) and superoxide dismutase (SOD) (10). These antioxidants are one of the body’s initial defense against inhaled environmental toxins and therefore, could be an important determinant of individual susceptibility to air pollutants.

The study found that omega-3 intake from fish oil (2 g per day) for four months has been found to increase SOD activity by 49% and GSH level by 62%, while decreasing oxidation of lipids by 72%. Thus, it appears that omega-3 fatty acids are able to modulate PM2.5 induced oxidative stress by increasing the activity of antioxidants in the RTLFs.

Vitamin C & E
Vitamin C and E are key lipid-soluble and water-soluble antioxidants in humans that may be helpful in reducing air pollution-induced oxidative stress.

The effect of vitamin C and E was evaluated in a study on individuals exposed directly or indirectly to coal burning emissions from an electric-power plant (11).

Oxidative stress biomarkers were measured before and after supplementation with vitamin C (500 mg) and vitamin E (800 mg) for six months and compared to a non-exposed control group.

In individuals exposed to airborne pollutants, markers of lipid and protein damage increased and the levels of non-enzymatic antioxidants (vitamin E, reduced glutathione and protein thiols) decreased.

The activities of several enzymes involved in the antioxidant defense system (catalase, glutathione peroxidase, glutathione reductase and glutathione S-transferase) were impaired, while the activity of superoxide dismutase increased, suggesting increased utilization of antioxidants and activation of the oxidative stress defense system in the presence of inhaled pollutants.

In these subjects, supplementing with vitamin C and E helped to reduce markers of lipid and protein damage and improved both enzymatic and non-enzymatic antioxidant defenses.

B Vitamins
B vitamins refer to a group of water-soluble vitamins that play important roles in cell metabolism. Each B vitamin is either a cofactor for key metabolic processes or is a precursor needed to make one.

In a human trial, 10 healthy adults were given fake pills (placebo) for two weeks and were then exposed to sham, particle-free medical air for 2 hours (12). This was followed by another four weeks of fake pills before the participants were exposed to concentrated ambient PM2.5 (250 μg/m3) for 2 hours. Finally, participants were given B vitamin tablets for another four weeks and then exposed to polluted air for 2 hours again. Resting heart rate (HR), heart rate variability (HRV), total white blood cell (WBC) counts, and lymphocyte (a type of white blood cell) count were measured before, immediately after and 24-hour after each exposure.

Results show that compared to sham, exposure to ambient PM2.5 for two hours increased HR, WBC count, lymphocyte count, and reduced HRV in healthy adults.

However, an intake of B vitamins for four weeks (once a day; each tablet contains 2.5 mg folic acid, 50 mg vitamin B6, and 1 mg vitamin B12) reduced PM2.5 effect on heart rate by 150%, HRV by 90%, WBC count by 139%, and lymphocyte count by 106%.

A separate study evaluated the effects of air pollution, genetic variations in metabolic genes and dietary intake of methyl nutrients (folate, vitamin B6, vitamin B12 and methionine from food sources) on HRV (13).

It found that people who carry certain genes which put them at a higher risk of cardiovascular disease had a significantly more pronounced decrease in HRV than those without when exposed to ambient PM2.5.

In addition, higher dietary intake of vitamin B6 (≥ 3.65 mg/day), vitamin B12 (≥ 11.1 µg/day), folate (≥ 495.8 µg/day) and methionine (≥ 1.88 mg/day) is found to negate the negative effects of PM2.5 on HRV.

The protective effects of B vitamins may be due to their anti-inflammatory, antioxidant and immuno-epigenetic properties. In the presence of air pollution, adequate vitamin B intake ensures proper epigenetic status of white blood cells (leukocytes), enabling the cells to carry out their immuno-regulation job properly, as well as prevents excessive oxidative damage to the cardiovascular system (14).

https://blissair.com/reduce-negative...-pollution.htm