Air pollution is becoming a major health problem that affects millions of people worldwide. In support of this observation, the World Health Organization estimates that every year, 2.4 million people die because of the effects of air pollution on health. Mitigation strategies such as changes in diesel engine technology could result in fewer premature mortalities, as suggested by the US Environmental Protection Agency.

This review:

1.  discusses the impact of air pollution on respiratory disease;
2. provides evidence that reducing air pollution may have a positive impact on the prevention of disease; and
3. demonstrates the impact concerted polices may have on population health when governments take actions to reduce air pollution.

Pollution is something that is prevalent in all parts of our country. To understand what exactly a pollution we should know about the problem of pollution.

What is Pollution?

Pollution is defined as the introduction of contaminants into the natural environment that cause adverse change. In simple words when agents like air, water etc. gets contaminated with harmful particles it gives rise to Pollution. It is increasingly recognized that implementation of strategies to reduce pollution can have substantial health benefits.

For example, the Environmental Protection Agency proposed that the implementation of measures to reduce emissions from diesel engines could result in 12 000 fewer mortalities and prevent 15 000 heart attacks and 8900 hospital admissions in the United States each year.2 The aim of this review is to provide information on the impact of pollution on respiratory health, as well as to discuss strategies for reducing air pollution, as proposed in a number of clinical reports. Particulate matter (PM) and ozone (O3) pollution are major causes of concern in the community.

Types of pollution:

As we have seen above pollution is basically of 2 types:

1. Water Pollution
2. Air Pollution

Causes of Pollution

When we talk about pollution the first word that comes in our mind is the capital of India i.e. Delhi. Delhi is vigorously struck with the highest level of air pollution in recent years. The major reason we have seen in seen in recent years for pollution in Delhi are firecrackers and burning of crops (Parali) from neighbouring states.

These elements results in high AQI (Air Quality Index). The toxic levels of air pollution in and around Delhi is creating quite a menace. Adding to the severity, the changing weather conditions have locked the pollutants in the air and made the situation worse. Doctors are warning people of dire consequences and discouraging them from stepping outdoors. The reasons or causes for the pollution are:

1. National capital shares its border with the states of Haryana and Uttar Pradesh. One of the main reasons of increasing air pollution levels in Delhi is crop burning by the farmers in these states. Farmers burn rice stubbles in Punjab, Haryana and Uttar Pradesh. It is estimated that approximately 35 million tonnes of crop are set on fire by these states. The wind carries all the pollutants and dust particles, which have got locked in the air.
    
2. Pollution caused by the traffic in Delhi is another reason for contribution of this air pollution and smog. The air quality index has reached severe levels. Vehicular emission is increasing the hazardous effects of air pollution and smog. The Central Pollution Control Board (CPCB) and the National Environmental Engineering Research Institute (NEERI) have declared vehicular emission as a major contributor to Delhi's increasing air pollution.
    
3. Another reason of air-pollution is over-population in the capital. Overpopulation only adds up to the various types of pollution, whether it is air pollution or noise pollution.
    
4. Large scale construction of buildings in Delhi-NCR is another issue that is increasing the level of dust and pollution in the air. Considering the dipping air quality, a number of construction sites have stalled work, as directed by the Delhi Government.
    
5. Investing less on public Infrastructure is another reason of air pollution. In India, investment in public transport and infrastructure is low which leads to congested roads, and thus it results in air pollution.

Levels of Pollution

Pollution levels in Delhi-National Capital Region increased marginally on Tuesday, mainly due to slow wind speed.

The overall air quality index (AQI) in the city read 270. up to 252. Nehru Nagar was the most-polluted area with an AQI of 330 and Dilshad Garden (163) the least polluted. Neighbouring Ghaziabad (300), Greater Noida (268), Gurgaon (186) and Noida (259) also recorded a marginal dip in air quality. An AQI between 201 and 300 is considered poor, 301-400 very poor and 401-500 severe.

Weather experts said slow surface winds led to accumulation of pollutants and the intensity of rains will be the deciding factor . If sufficient rains occur. the pollutants will be washed away, while scanty rains could prove counter-productive.

Skymet Weather, a private forecaster, said patchy rains are possible over Delhi and NCR. Parts of Haryana, Punjab and Uttar Pradesh will also get scattered rains.Pollution in Delhi and NCR is increasing once again. It may increase further .

Polluting particles 30 times finer than one human hair, that can enter the bloodstream and sicken or kill people--in Delhi's air were recorded at a 24-hour average of 625 microgram per cubic metre (µg/m3) of air, the seasons worst. This is 24 times higher than the World Health Organization (WHO)-prescribed safe levels of 25 µg/m3 (24-hour average) and nine times higher than the laxer Indian standard of 60 µg/m3 (24-hour average)

Air pollution is not only a winter problem. Year-round, the level (of air pollution) remains three times higher than the national standard. Unless we bring down the annual concentration significantly, health burden will not reduce, Dey told IndiaSpend. To fight air pollution, governments need not only emergency measures when pollution spikes, but year-round air pollution reduction drives across sectors.

During the first five days of November 2019, when the focus was on Delhi's severe level of pollution, it was not the worst-polluted among the nearly 100 cities across India that the Central Pollution Control Board (CPCB) monitors daily. On three (November 2, 4 and 5) out of five days, Delhi did not even make it to the list.

Yet, media attention was narrowly focused on Delhi. The government has a National Clean Air Programme (NCAP) with a target of reducing pollution by 20-30% across India by 2024. The entire Indo-Gangetic Plain has pollution levels at an annual scale more than double the Indian standard. Today, more than 76% of the population lives in places that do not meet Indian air quality standards. Unless we form an intersectoral plan, it will not work. We think that rural areas are not polluted, but studies have shown that emission from household activities (cooking and heating with solid biomass and kerosene lighting) has the highest contribution at the national scale, higher than contributions from transport, power plants and industry. NCAP is a good start.

We have Ujjwala programme running and its successful implementation would ensure a large reduction in the regional pollution level. Eventually programmes such as NCAP, Ujjwala, Smart City Missions need to be linked.

Effects of Pollution

1. Hazardous to Human Health
   Air Pollution threatens the human health in various ways. It causes lung disease and other respiratory problems. According to World Health Organization (WHO) report in 2013, it postulates air pollution causes two million premature deaths annually. Furthermore, the WHO report emphasizes that majority of the deaths are experienced in developing countries. Long-term exposure to air pollution also adversely affects the lungs of young and growing children and may worsen medical conditions among the aged people. Perhaps, this is the reason air pollution is perceived as a relentless and quiet killer.
    
2. Acid Rain
   When the particles, chemicals, and pollutant gasses present in the atmosphere chemically react with water molecules and oxygen, they form acidic compounds. These acidic chemical compounds then combine with various forms of precipitation such as snow, fog, rain, or sleet to form acid rain.
    
3. Eutrophication
   Eutrophication refers to the process whereby a water body acquires excessive concentrations of nutrients, particularly owing to runoff deposits of nitrates and phosphates. As a result, it usually encourages the dense growth of plant life and algae. When the plant life and algae die and decompose, the resultant organic matter quickly depletes the available oxygen in the water causing the death of animal life such as fish.
    
4. Other effects
   from the widespread effects of human and animal health as well as the impacts to the environment and vegetations, air pollution also affects our surrounding in several ways. At times when one takes a keen look at the streets of big cities, it is easy to spot how blackened some of the buildings look. The trend is widespread and evident even in places where power plants or factories do not exist. The blackening of the buildings is predominantly caused by exhaust and soot from cars, buses, or heavy duty tracks. Accordingly, it usually necessitates the need for repainting from time to time, further generating emissions from paints and chemical solvents. Besides, exhaust fumes contribute to acid rain that leads to weathering of buildings, corrosion of metals, and peeling of paints on surfaces.
    

Government Measures For Pollution

Urgent actions are required to help reduce air pollution in Delhi, one of the most polluted cities in the world, and restore various air parameters to levels safe for the health of its citizens and visitors. Here are few steps that can play an instrumental role in reducing air pollution in Delhi, which reached alarming levels of 485 AQI (air quality index), when the safe limit for humans is less than 100 AQI.

1. Car pooling: Reduce traffic-based air pollution and congestion by starting car pool lanes for those cars and four wheelers that have three or more passengers to encourage people to go for car pooling. Meanwhile, citizens too should take initiative and car pool with friends, colleagues, family wherever possible.
    
2. Use bicycles: Mark out bicycle lanes in residential colonies as well as on all roads in Delhi to encourage safe travel by bicycles. Meanwhile, citizens should also be encouraged to use bicycles.
    
3. Public transport: Encourage greater use of public transport by supporting the Metro, overhead rail and bus services to make it convenient for people to travel by public transport affordably and safely instead of using their own vehicles. Citizens too must shed hang-ups over social status and try to travel by public transport proactively.
    
4. More CNG vehicles: Encourage use of CNG in motor vehicles as it is a much cleaner fuel than petrol or diesel by considerably reducing the road tax and sales tax on CNG filled cars as compared to petrol and diesel four wheelers. Since there are at least 1,400 cars added to Delhi roads every day, all the cars should be restricted to using CNG only as all new petrol cars can be converted to CNG. Also, new registrations should be discouraged by enhancing registration charges.
    
5. Fuel-efficient cars: Encourage more fuel efficient four wheelers with better mileage per litre through road tax and sales tax incentives in addition to CNG requirement. Citizens should opt for more efficient and smaller cars that can run on CNG as alternate fuel.
    
6. Bigger trucks: Encourage six-axle trucks rather than the typical four-axle ones to increase the pay load per truck to reduce the number of trucks on roads. Trucks going to other destinations must not be allowed to pass through Delhi and only use the bypass.
    
7. Road signs: Improve the poor road signs so that people do not travel extra to locate their destinations. All the signs must be signposted at two or three places well before the turning rather than at the last minute.
8. Maintenance of roads: Better maintain roads to complexes such as Nehru Place to reduce the time a four wheeler spends on plying on such poor roads.
    
9. Shared taxis: The transport department should encourage shared taxi services by developing a taxi sharing website and set up taxi stands and cabs to offer reduced fares for shared service. This is other than the facilities Ola and Uber provide.
    
10. Burning waste: Burning of leaves, old tyres or any items in the open should be made a punishable offence in NCR with a fine of Rs 10,000 per incident as this is a major cause of air pollution. Citizens should be asked to report such incidents to helpline numbers and emails.
     
11. Solar power: Installation of solar panels should be encouraged at homes, multi-storey buildings and commercial establishments so that decentralised power is generated with suitable subsidies to make it financially viable for all households. The cost of solar panels has come down considerably. This should help retire all coal-based thermal power plants which are adding a lot to Delhi's air pollution problems and adversely effecting climate change. In fact, thermal power plants in Delhi-NCR should be stopped from functioning till the AQI level is under 200.
     
12. Power backup: Inverters should be encouraged for back up supply and diesel generator sets should not be allowed to run in Delhi-NCR till the AQI level comes below 200.
     
13. Dump sites: Landfills should be better managed by the government to ensure there are no fires there.
     
14. RO-RO on roads: The present RO-RO (Roll-on-Roll-off) scheme launched by Indian Railways to carry loaded trucks on goods train to decongest Delhi roads and to reduce air pollution needs to be given a fill up and made compulsory for trucks which otherwise pass through Delhi.

Measures of Pollution

The average AQI of Delhi from January 1 to November 4 this year was 195. The same figure for 2018 was 204. With a reduction of 9 points or 4 per cent for 2019, the average AQI has improved from poor to moderate.

Being the capital, Delhi is watched closely for its severe air pollution every year during winters. While stubble burning in neighbouring states is blamed majorly, multiple studies have attempted to find solutions to the same. And now, India Today Data Intelligence Unit (DIU) has found that Delhi hardly had two days of good air in 2019.

AQI is considered to be good if it is below 50. From January 1 to November 5 this year, the Capital had only two such days when the AQI averaged below 50 for 24 hours. This was on August 17 and 18 when Delhi had an average AQI of 49 on both days.

But this is both good and bad. Good because Delhi didnt have a single good air day in 2018, and bad because the number of days with good air is extremely low.

On average, Delhi's AQI till November 4 is better than what it was last year.

AQI of Delhi from January 1 to November 4 this year was 195. The same figure for 2018 was 204. With a reduction of 9 points or 4 per cent for 2019, the average AQI has improved from poor to moderate.

A closer look at the statistics shows a significant decline in the number of days with poor and very poor air quality days.

The number of days the Capital inhaled poor quality air decreased from 102 in 2018 to 85 in 2019. Similarly the number of days with very poor quality air also fell from 39 to 34.
Thus, there was a reduction of 22 days with poor and very poor air quality

Conclusion
While reviewing existing environmental regulation in India, the TSR Subramanian Committee bluntly notes that the legislations are weak, monitoring is weaker, and enforcement is weakest. In this paper, we assert the need for greater investments in monitoring that yields reliable data, taking advantage of advances in technology and reduced costs of monitoring equipment, and considering the incentives of third party agencies tasked with the monitoring.

We argue that compliance and hence enforcement may improve if regulations are designed in a manner that is compatible with the incentives of the regulated entities. We also make the case that market based instruments, like congestion pricing or cap-and-trade, offer the potential of a rare win-win in that they can reduce compliance costs and reduce pollution allowing for urgent improvements in health.

This is because these regulatory mechanisms seek to reduce to a minimum the costs of cutting total emissions into the ambient. As such, they seem particularly well suited to bridge Indias perceived conflict between improving environmental performance whilst maintaining robust levels of economic growth.

Finally, regardless of the type of regulation, it is essential that new interventions need to be piloted and rigorously tested.

References

1. India today survey on Delhi air pollution
2. Environmental studies