My Science School

The Mekong is one of the longest rivers in the world, cutting across several Asian regions from Tibet and China to Thailand and Cambodia. But spanning a large area means the threats it faces are just as huge. What are they? Come, let's find out.

Waste generated in any region is disposed of in many ways, including being dumped at landfills. (Only a minuscule fragment of waste is recycled globally.) Some countries export their waste. Several Asian countries have been taking in plastic waste from such countries, without really being equipped to handle waste disposal safely. In addition, these Asian countries have their own waste to deal with. The waste in landfills reach rivers and oceans through winds, rains, and drains. One such river is the Mekong. Painfully, three "of the worst six plastic polluting countries China, - Thailand, and Vietnam - have a presence in Mekong", meaning the quantum of waste this river takes in is huge and increasing. The pandemic, with its masks, plastic sanitiser containers, take-away plastic boxes, etc., has exacerbated the situation. And, this is of grave concern.

The Mekong is a treasure trove of biodiversity - several species of plants, birds, reptiles, and fishes call the river and its surrounding regions home. But in the current scenario, rubbish is finding its way into the water, endangering wildlife. Animals and birds are in danger of being affected by plastic debris through entanglement or ingestion. There have been instances of dead whales "turning up in Thailand and Indonesia with many kilograms of plastics in their stomachs". It is not just wildlife that's affected. When humans consume creatures such as fish, we end up consuming plastic, which has the potential to cause serious health problems such as cancer. Since rivers drain into larger waterbodies such as seas (the Mekong mixes with the South China Sea) and oceans, the pollution they carry is transferred too.

An increase in the pollution of waterbodies is an indication of increasing pollution on land. And a grim reminder that unless we change our lifestyles to make this planet greener, we are likely to face the negative consequences of our own actions.

Picture Credit : Google 

Air Quality Index indicates how safe or polluted the air is, and the health concerns involved

The air quality deteriorates throughout India in October and November every year due to festivals, among other reasons. Post-Deepavali, Air Quality Index (AQI) is the most-talked about.

What is AQI?

The AQI is the yardstick used to report how clean or polluted the air is. It is used to help people know how the local air quality impacts their health. These indices indicate whether the amount of nitrogen dioxide, carbon monoxide, and sulfur dioxide in the air exceeds the criteria set by the World Health Organisation (WHO) or not.

How is AQI calculated?

 To calculate AQI, an air monitor and an air pollutant concentration over a specified averaging period is needed. The results are grouped into ranges, and each range is assigned a descriptor, a colour code, and a standardised public health advisory.

The AQI categories are - Good (0-50), Satisfactory (51-100), Moderately polluted (101-200), Poor (201-300), Very Poor  (301-400), and Severe (401-500) - with colour coding ranging from green to dark red.

What are AQI pollutants?

India launched the National Air Quality Index Standard (NAQI) on September 17, 2014. The National Air Monitoring Program (NAMP) covering 240 cities in the country is operated by the Central Pollution Control Board (CPCB).

In India, the AQI keeps a tab on eight major air pollutants in the atmosphere - Particulate Matter (PM10), Particulate Matter (PM2.5), Nitrogen Dioxide (NO2), Sulphur Dioxide (SO2), Carbon Monoxide (CO), Ozone (03), Ammonia (NH3), and Lead (Pb).

Health risks

An increase in AQI increases public health risks, especially affecting children, elderly, and individuals with respiratory or cardiovascular issues.

During these times, governments generally urge people to reduce physical activity outdoors, or even avoid going out altogether. The use of face masks such as cloth masks are also recommended.

Picture Credit : Google 

New research suggests that simple measure that can be implemented in many schools has a telling influence on air quality. Schools form an integral part of childhood. Worldwide, an estimated 10 million students spend 30% of their daily lives at schools. Out of their duration at school, 70% of the time is spent indoors. Low air quality in such environments leave the children vulnerable to many respiratory diseases, behavioural problems, affect lung and brain health, and even lead to an increased risk of cancer.

Poor air quality

Many schools in our country breach the limits set by the World Health Organisation for air quality. In such a climate, enhancing the surroundings in whatever little way helps in the overall scheme of things. There's good news, however, as new research suggests that simple measures that can be implemented in many schools has a telling influence on air quality.

In a paper titled "Investigation of air pollution mitigation measures, ventilation, and indoor air quality at 5 three schools in London", researchers from the University of Surrey listed their findings. The paper, published in the journal Atmospheric Environment, is available online and will be part of the 1 ? issue dated November 15, 2022.

Simple initiatives

Researchers investigated if putting up a green screen along the perimeter of the school, installing air purifiers in classrooms, and organising street initiatives during drop-off and pick-up hours had an effect in classrooms and playgrounds. They did this by working with a select number of London schools.

Installation of air purifiers in classrooms reduced indoor pollution concentrations by up to 57%. The street initiatives, which forces motor vehicles to not ply on roads with schools at the start and end of school days, reduced the particle concentrations by up to 36%.

Based on wind conditions, green screens at school boundaries were also effective. In the best case, they were able to reduce some of the most dangerous outdoor particle levels from the roads by up to 44%.

As ensuring that schools have green perimeters, lesser vehicular traffic during pick-up and drop-off, and installing air purifiers in classrooms are simple and affordable techniques, these can be replicated everywhere. While their effectiveness would have to be studied further, methods like these will eventually ensure that schools remain safe spaces to learn.

Picture Credit : Google