Editorial Articles

volume-9, 1 - 7 June 2019

World Environment Day

Controlling Air Pollution

Dr. Pawan Kumar 'Bharti'

The UN Environment Programme (UNEP) every year organizes events for World Environment Day (WED), which encourages worldwide awareness and action for the protection of environment. WED is celebrated on 5 June in over 100 countries since the first day of Stockholm conference. In 2019, China will host the global World Environment Day celebrations on the theme, 'Air Pollution'.

World Environment Day (WED) is celebrated on the 5th of June every year, and is the United Nation's principal vehicle for encouraging awareness and action for the protection of our environment. First held in 1974, it has been a flagship campaign for raising awareness on emerging environmental issues from marine pollution, human overpopulation, and global warming, to sustainable consumption and wildlife crime. WED has grown to become a global platform for public outreach, with participation from over 143 countries annually. Each year, WED has a new theme that major corporations, NGOs, communities, govern-ments and celebrities worldwide adopt to advocate environmental causes.

World Environment Day was established by the UN General Assembly in 1972 on the first day of the Stockholm Conference on the Human Environment, resulting from discussions on the integration of human interactions and the environment. Two years later, in 1974 the first WED was held with the theme "Only One Earth". Even though WED celebration has been held annually since 1974, in 1987 the idea for rotating the center of these activities through selecting different host countries began.

World Environment Day is to be held on Wednesday June 5th 2019, and is on June 5th every year. It isn't a public holiday; it is an environmental awareness day, run by the United Nations. It is sometimes also unofficially called Eco Day or Environment Day. The aim of the Day is to raise awareness of the environment and specific environmental issues.

On 15 March 2019, the head of Chinese delegation, Zhao Yingmin, Vice Minister of Ecology and Environment, and Joyce Msuya, Acting Head of UN Environment, jointly announced at Nairobi that China will host the global World Environment Day celebrations on 5 June 2019 with a theme of air pollution.


Since last five decades, World Environment Day has been raising awareness, supporting action, and driving change. Here is a glimpse of themes and recent history of last WEDs:


In 2019, China will host the global World Environment Day celebrations on the theme, 'Air Pollution'.


The theme for 2018 is "Beat Plastic Pollution". The host nation is India. By choosing this Theme, it is aimed that people may strive to change their everyday lives to reduce the heavy burden of plastic pollution. People should be free from the over-reliance on single-use or disposables, as they have severe environmental consequences. We should liberate our natural places, our wildlife - and our own health from plastics. Indian government pledged to eliminate all single use of plastic in India by 2022.


The theme for 2017 was 'Connecting People to Nature - in the city and on the land, from the poles to the equator'. The host nation was Canada.


The 2016 WED was organized under the theme "Go wild for life". This edition of the WED aims to reduce and prevent the illegal trade in wildlife. Angola was chosen as the host country of the 2016 WED during the COP21 in Paris.


The Slogan of the 2015 edition of the World Environment Day is "Seven Billion Dreams. One Planet. Consume with Care". The slogan was picked through a voting process on social media. In Saudi Arabia, 15 women recycled 2000 plastic bags to crochet a mural in support of the WED 2015. In India, Narendra Modi planted a Kadamb sapling to celebrate the World Environment Day and raise awareness for Environment. Italy is the host country of the 43rd edition of the WED. The celebrations took place as part of Milan Expo around the theme: Feeding the Planet - Energy for Life.


The Theme of the 2014 WED was: International Year of Small Islands Developing States (SIDS). By choosing this Theme the UN General Assembly aimed to highlight the development Challenges and successes of the SIDS. In 2014, the World Environment Day focused on global warming and its impact on ocean levels. The Slogan of the WED 2014 is "Raise your voice not the sea level", as Barbados hosted the global celebrations of the 42nd edition of the World Environment Day. The UN Environment Programme named actor Ian Somerhalder as the official Goodwill ambassador of the WED 2014.


The 2013 theme for World Environment Day was Think.Eat.Save. The campaign addressed the huge annual wastage and losses in food, which, if conserved, would release a large quantity of food as well as reduce the overall carbon footprint. The campaign aimed to bring about awareness in countries with lifestyles resulting in food wastage. It also aimed to empower people to make informed choices about the food they eat so as to reduce the overall ecological impact due to the worldwide production of food. The host country for the year's celebrations was Mongolia.


The theme for the 2012 World Environment Day was Green Economy: The theme aimed to invite people to examine their activities and lifestyle and see how the concept of a "Green Economy" fits into it. The host country for the year's celebrations was Brazil.


The theme for 2011 was Forests-Nature At Your Service. Thousands of activities were organized worldwide, with beach clean-ups, concerts, exhibits, film festivals, community events and much more. That year's global host, India, is a country of wide biodiversity.


'Many Species. One Planet. One Future', was the theme of 2010. It celebrated the diversity of life on Earth as part of the 2010 International Year of Biodiversity. It was hosted in Rwanda. Thousands of activities were organized worldwide, with beach clean-ups, concerts, exhibits, film festivals, community events and much more. Each continent (except Antarctica) had a "regional host city", the U.N. chose Pittsburgh, Pennsylvania as the host for all North.


The theme for WED 2009 was 'Your Planet Needs You - UNite to Combat Climate Change', and Michael Jackson's 'Earth Song' was declared 'World Environment Day Song'. It was hosted in Mexico.


The host for World Environment Day 2008 was New Zealand, with the main inter-national celebrations scheduled for Wellington. The slogan for 2008 was "CO2, Kick the Habit! Towards a Low Carbon Economy." New Zealand was one of the first countries to pledge to achieve carbon neutrality, and will also focus on forest management as a tool for reducing greenhouse gases. The Chicago Botanic Garden served as the North American host for World Environment Day on 5 June 2008.


The topic for World Environment Day for 2007 was "Melting Ice - a Hot Topic?" During International Polar Year, WED 2007 focused on the effects that climate change is having on polar ecosystems and communities, on other ice- and snow-covered areas of the world, and the resulting global impacts.

The main international celebrations of the WED 2007 were held in the city of Tromsø, Norway, a city north of the Arctic Circle.


The topic for WED 2006 was Deserts and Desertification and the slogan was "Don't desert drylands". The slogan emphasised the importance of protecting drylands. The main international celebrations of the World Environment Day 2006 were held in Algeria.


The theme for the 2005 World Environment Day was "Green Cities" and the slogan was "Plan for the Planet!".

World Environment Day (WED) was established in 1972 but first held in 1974, which shows that concern about the environment goes back several decades at least. 143 countries take part in World Environment Day, and the day focuses on environmental concerns ranging from pollution to global warming and sustainable food production to protection of wildlife.

World Environment Day can be celebrated in many ways, activities such as clear up campaigns are popular and will be prominent this year, also concerts, conventions and parades, tree planting, and lectures. Promotional materials for the day tend to be created using natural environmental colours.

Participants of WED include NGOs, governments, comm-unities, individuals, charities, organizations and celebrities, and together they raise awareness of environmental issues. Each year a country or Nation hosts WED. World Environment Day has had its own anthem since 2013.

World Environment Day Anthem

An Earth Anthem penned by poet Abhay K is sung to celebrate World Environment Day.

Our cosmic oasis, cosmic blue pearl the most beautiful planet in the universe all the continents and the oceans united we stand as flora and fauna united we stand as species of one earth different cultures, beliefs and ways we are humans, the earth is our home all the people and the nations of the world all for one and one for all united we unfurl the blue flag.

It was launched in June 2013 on the occasion of the World Environment Day by Kapil Sibal and Shashi Tharoor, then Union Ministers of India, at a function organized by the Indian Council of Cultural Relations in New Delhi. It is supported by the global organization Habitat For Humanity.

WED 2019 theme:

Air Pollution

Air pollution occurs when harmful or excessive quantities of substances including gases, particles, and biological molecules are introduced into Earth's atmosphere. It may cause diseases, allergies and even death to humans; it may also cause harm to other living organisms such as animals and food crops, and may damage the natural or built environment. Both human activity and natural processes can generate air pollution.

Indoor air pollution and poor urban air quality are listed as two of the world's worst toxic pollution problems in the 2008 Blacksmith Institute World's Worst Polluted Places report. According to the 2014 World Health Organization report, air pollution in 2012 caused the deaths of around 7 million people worldwide, an estimate roughly echoed by one from the International Energy Agency.

An air pollutant is a material in the air that can have adverse effects on humans and the ecosystem. The substance can be solid particles, liquid droplets, or gases. A pollutant can be of natural origin or man-made. Pollutants are classified as primary or secondary. Primary pollutants are usually produced by processes such as ash from a volcanic eruption. Other examples include carbon monoxide gas from motor vehicle exhausts or sulphur dioxide released from the factories. Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact. Ground level ozone is a prominent example of secondary pollutants. Some pollutants may be both primary and secondary: they are both emitted directly and formed from other primary pollutants.

Air pollution is a mixture of natural and man-made substances in the air we breathe.  It is typically separated into two categories:

Outdoor air pollution involves exposures that take place outside of the built environment. Examples include:

  • Fine particles produced by the burning of fossil fuels
  • Noxious gases (sulphur dioxide, nitrogen oxides, carbon monoxide, chemical vapors, etc.)
  • Ground-level ozone (a reactive form of oxygen and a primary component of urban smog)
  • Tobacco Smoke

Indoor air pollution involves exposures to particulates, carbon oxides, and other pollutants carried by indoor air or dust. Examples include:

  • Gases (carbon monoxide, radon, etc.)
  • Household products and chemicals
  • Building materials (asbestos, formaldehyde, lead, etc.)
  • Outdoor indoor allergens (cockroach and mouse dropping, etc.)
  • Tobacco smoke
  • Mold and pollen

Human exposure

Air pollution risk is a function of the hazard of the pollutant and the exposure to that pollutant. Air pollution exposure can be expressed for an individual, for certain groups, or for entire populations. For example, one may want to calculate the exposure to a hazardous air pollutant for a geographic area, which includes the various microenvironments and age groups. This can be calculated as an inhalation exposure. This would account for daily exposure in various. The exposure needs to include different age and other demographic groups, especially infants, children, pregnant women and other sensitive subpopulations. The exposure to an air pollutant must integrate the concentrations of the air pollutant with respect to the time spent in each setting and the respective inhalation rates for each subgroup for each specific time that the subgroup is in the setting and engaged in particular activities. The daily exposure, then, needs to reflect the time spent in each micro-environmental setting and the type of activities in these settings. The air pollutant concentration in each micro-activity/micro-environmental setting is summed to indicate the exposure. For some pollutants such as black carbon, traffic related exposures may dominate total exposure despite short exposure times since high concentrations coincide with proximity to major roads or participation to traffic.

Health effects

In 2012, air pollution caused premature deaths on average of 1 year in Europe, and was a significant risk factor for a number of pollution-related diseases, including respiratory infections, heart disease, COPD, stroke and lung cancer. The health effects caused by air pollution may include difficulty in breathing, wheezing, coughing, asthma and worsening of existing respiratory and cardiac conditions. These effects can result in increased medication use, increased doctor or emergency department visits, more hospital admissions and premature death. The human health effects of poor air quality are far reaching, but principally affect the body's respiratory system and the cardiovascular system. Individual reactions to air pollutants depend on the type of pollutant a person is exposed to, the degree of exposure, and the individual's health status and genetics. The most common sources of air pollution include particulates, ozone, nitrogen dioxide, and sulphur dioxide. Children aged less than five years that live in developing countries are the most vulnerable population in terms of total deaths attributable to indoor and outdoor air pollution.

Reduction efforts

Various air pollution control technologies and strategies are available to reduce air pollution. At its most basic level, land-use planning is likely to involve zoning and transport infrastructure planning. In most developed countries, land-use planning is an important part of social policy, ensuring that land is used efficiently for the benefit of the wider economy and population, as well as to protect the environment.

Because a large share of air pollution is caused by combustion of fossil fuels such as coal and oil, the reduction of these fuels can reduce air pollution drastically. Most effective is the switch to clean power sources such as wind power, solar power, hydro power which don't cause air pollution. Efforts to reduce pollution from mobile sources includes primary regulation (many developing countries have permissive regulations), expanding regulation to new sources (such as cruise and transport ships, farm equipment, and small gas-powered equipment such as string trimmers, chainsaws, and snowmobiles), increased fuel efficiency (such as through the use of hybrid vehicles), conversion to cleaner fuels or conversion to electric vehicles.

Titanium dioxide has been researched for its ability to reduce air pollution. Ultraviolet light will release free electrons from material, thereby creating free radicals, which break up VOCs and NOx gases. One form is superhydrophilic.

Air quality standards:





Time Weighted


Concentration in Ambient Air

Methods of Measurement

Industrial Residential

Rural and Other Area

Ecologically sensitive area (notified by Central Govt.)








Sulphur Dioxide (SO2), g/m3




·   Improved West and Geake

·  Ultraviolet fluorescence

24 hours**




Nitrogen Dioxide  (NO2), g/m3




·  Modified Jacob & Hochheiser (Na-Arsenite)

·  Chemiluminescence

24 hours**




Particulate Matter (size less than 10 μm) or PM10μg/m3




·  Gravimetric


·  Beta attenuation

24 hours**




Particulate Matter (size  less than 2.5 microns)  or PM2.5 mg/m3




·  Gravimetric


·  Beta attenuation

24 hours**




Ozone (O3)  mg/m3

8 hours **



·  UV photometric

·  Chemiluminescence

·  Chemical method

1 hour **




Lead (Pb) μg/m3




·  ASS / ICP method after sampling on EPM  2000  or  equivalent filter paper

·  ED-XRF using Teflon filter

24 hours**




Carbon Monoxide  (CO) mg/m3

8 hours**



·  Non Dispersive Infra RED (NDIR) Spectroscopy

1 hour**




Ammonia (NH3) μg/m3




·  Chemiluminescence

·  Indophenol blue method

24 hours**




Benzene (C6H6) μg/m3




·   Gas chromatography based ontinuous analyser

·   Adsorption and desorption followed by GC analysis


Benzo (a) Pyrene (BaP) - particulate phase only ng/m3




Solvent extraction followed by HPLC / GC analysis


Arsenic (As) ng/m3




AAS/ICP method after sampling on EPM 2000 or equivalent filter paper


Nickel (Ni) ng/m3




AAS/ICP method after sampling on EPM 2000 or equivalent filter paper




* Annual arithmetic mean of minimum 104 measurements in a year at a particular site taken twice a week 24 hourly at uniform intervals.

** 24 hourly or 8 hourly or 1 hourly monitored values, as applicable, shall be complied with 98% of the time in a year. 2% of the time, they may exceed the limits but not on two consecutive days of monitoring.

Control devices

The following items are commonly used as pollution control devices in industry and transportation. They can either destroy contaminants or remove them from an exhaust stream before it is emitted into the atmosphere.

Particulate control

Mechanical collectors (dust cyclones, multi-cyclones)

Electro Static Precipitators (ESP), Bag houses

Particulate scrubbers


Baffle spray scrubber

Cyclonic spray scrubber

Ejector venturi scrubber

Mechanically aided scrubber

Spray tower

Wet scrubber

NOx control

Low NOx burners

Selective Catalytic Reduction (SCR)

Air Pollution facts:

·      92 per cent of people worldwide do not breathe clean air

·      Air pollution costs the global economy $5 trillion every year in welfare costs

·      Ground-level ozone pollution is expected to reduce staple crop yields by 26 per cent by 2030


Selective Non-Catalytic Reduction (SNCR)

NOx scrubbers

Exhaust gas recirculation

Catalytic converter (also for VOC control)

VOC abatement

Adsorption systems, using activated carbon, such as Fluidized Bed Concentrator


Thermal oxidizers

Catalytic converters


Absorption (scrubbing)

Cryogenic condensers

Vapor recovery systems

Acid Gas/SO2 control

Wet scrubbers

Dry scrubbers

Flue-gas desulphurization

Mercury control

Sorbent Injection Technology

Electro-Catalytic Oxidation (ECO)


Dioxin and furan control

Miscellaneous associated equipment

Source capturing systems

Continuous Eemissions Monitoring Systems (CEMS)


(Author is an  environmentalist & freelance writer. He was the member of 30th Indian Scientific Expedition to Antarctica, e-mail: gurupawanbharti@ rediffmail. com)

Views expressed are personal.

(Image Courtesy : Google)