The atmosphere needs protection in the face of air pollution, ozone depletion and climate change. According to the WHO, air pollution is 'the biggest environmental risk to health' and 'a public health emergency, responsible for millions of premature deaths annually. Globally, 41% of households, over 2.8 billion people, rely on solid fuels for cooking and heating.

In developing countries, solid fuels are typically burnt in open fires and inefficient traditional cook stoves, often in poorly ventilated cooking spaces. In addition, people exposed to indoor air pollutants for the longest periods are often those most susceptible to their effects. Such groups include the young, the elderly, and the chronically ill, especially those suffering from respiratory or cardiovascular disease.

Poor air quality indoors can be especially harmful to vulnerable groups such as children, the elderly, and those with cardiovascular and chronic respiratory diseases such as asthma. Some of the main indoor air pollutants include:
Tobacco Smoke, Gases Or Particles From Burning Fuels, Chemicals and Allergens. Carbon Monoxide, Nitrogen Dioxides, Particles, And Volatile Organic Compounds can be found both outdoors and indoors.

The recent WHO indoor air quality guidelines4 are tailored to the particular needs of developing countries where the burden of household air pollution is greatest. The guidelines recognize the challenges likely to be faced in implementation and provide detailed information on cook stove performance and potential health risks.

Effective implementation of the guidelines will require strong environmental health programme to improve understanding of the complexities of the household air pollution problem and inform national response.5 Effective air pollution laws and policies require prompt action and cooperation at global, regional and national levels, reaching across most economic sectors6 and engaging the public.7

It is this apparent disconnect between the state of the complex problem and the law - as well as the urgency of the need to address it8 that motivated us to prepare this special issue. Some indoor air pollutants and their health impacts are better known and receive more public attention than others. Smoking bans in public spaces is one of them.

Significance Of Research
This paper is designed to increase the understanding of the atmosphere/exchange of greenhouse gases and to develop a model which can be used to investigate the human and climatic impact of greenhouse gases from a natural ecosystem. The research paper will focus on the various factors which will lead to the problem of climate change in India and also suggest the mitigation guidelines to combat climate change.

The significance of this study is to understand global environment change and how it will affect the nature and society of India. The importance of this study is to provide a range of options for reducing the risks to climate and global change and also suggests the developing actions that allow joint mitigation for lesser indoor pollutants.

Research Objectives
In 2010, household air pollution was estimated to be responsible for 3.5 million premature deaths worldwide.9 Household air pollution also contributes to outdoor air pollution, causing an additional 370 000 deaths and 9.9 million disability-adjusted life years globally in 2010.10 There is strong evidence linking household air pollution exposure with cardiovascular diseases,11/ 12 acute lower respiratory infections, chronic obstructive pulmonary disease and chronic bronchitis, lung cancer, cataract,13 low birth weight and stillbirth.14

Other health outcomes associated with household air pollution, for which evidence is less robust, include pharyngeal and laryngeal cancer,15 asthma, tuberculosis, neonatal mortality16 and nutritional deficit. Indirect health effects from collecting firewood include assault of women and girls, insect (including disease vector) and snake bites, school absenteeism and musculoskeletal injuries from having to carry large bundles of firewood on the head and back for long distances.17

The introductory article is structured as follows. It begins by discussing the sources and impacts of air pollution on human health, the economy and the environment. The article continues with a discussion of the applicability and functionality of customary international law, particularly the principles of international environmental law relevant to air pollution.

It then explains that the legal landscape on air pollution is fragmented and consists of myriad different regional instruments, as well as global instruments of a sectored nature (e.g., those relating to shipping and aviation). The article goes on to show the gaps in the international legal landscape in the coverage of some of the short-lived climate pollutants (SLCPs). Next, the article discusses the EU's approach to air pollution. The article concludes with some thoughts on the future of international law and global cooperation on air pollution.

Analysis
Improved cook stoves Interventions to reduce household air pollution have primarily focused on the promotion and dissemination of improved cook stoves.18 However, despite the distribution of millions of improved cook stoves in developing countries over the last three decades, problems with household air pollution persist.

This limited success is due to several factors, including lack of awareness of the problem and a lack of affordable stoves and fuels that reduce exposures appreciably.19 Lack of reliable exposure-response data has also been suggested as a reason for the failure of improved cook stoves to achieve the desired exposure reductions and health benefits.20

Biologic-Pollutants
Biologic pollutants include bacteria, molds, viruses, animal dander, cat saliva, dust mites, cockroaches, and pollen. These biologic pollutants can be related to some serious health effects. Some biologic pollutants, such as measles, chickenpox, and influenza are transmitted through the air. However, the first two are now preventable with vaccines.

Influenza virus transmission, although vaccines have been developed, still remains of concern in crowded indoor conditions and can be affected by ventilation levels in the home. Common pollutants, such as pollen, originate from plants and can elicit symptoms such as sneezing, watery eyes, coughing, shortness of breath, dizziness, lethargy, fever, and digestive problems. Allergic reactions are the result of repeated exposure and immunologic sensitization to particular biologic allergens.

Renewable energy resources
Solar, wind, hydro and geothermal power can serve as safe,21 affordable sources of household energy while mitigating global climate change.22Most countries have renewable energy potential23 many times their current energy consumption that can be exploited with current technology.

For example, many areas of sub-Saharan Africa24 experience daily solar radiation of between 14.4 and 21.6 MJ/m.25 Geothermal resources are abundant in east Africa with great potential for wind power also present around the coastal regions and eastern highlands.26 The Green Climate Fund is a promising source of funds to develop the infrastructure required to exploit these renewable energy resources.27

The in complete combus tion products of biomas s include suspended particulate matter, carbon monoxide, poly aromatic hydrocarbons, poly organic matter, formaldehyde, etc., which have adverse effects on health. The combustion of coal results in production of oxides of sulfur, arsenic, and fluorine.

Pollutants such as volatile, and semi volatile organic compounds are produced from resins, waxes, polishing materials, cosmetics, and binders. Lastly; biological pollutants like dust mites, molds, pollen, and infectious agents produced in stagnant water, mattresses, carpets, and humid too pollute indoor air for cooking.

Conclusion
Solid fuels are still in widespread use in developing countries and it appears that intervention efforts are not achieving their desired goals. Providing clean household energy solutions in the effort to tackle household air pollution in developing countries can also mitigate global climate change and help to achieve several of the sustainable development goals. In summary, the traditional legal approaches currently available under international law do not provide a comprehensive response to air pollution. The current legal landscape has developed on an ad hoc basis and as a result there are serious gaps in geographical and pollutant/pollution source coverage.

Furthermore, international law does not address the global impacts of air pollution. At the same time, developing a global treaty on air pollution seems unlikely in the near future. At EU level, the legal framework also fails to guarantee improved air quality due to problems of low ambition and poor implementation and compliance. That said, there is hope for strengthened global cooperation to tackle the persistent air pollution crisis as the issue is rising high in national and global policy agendas. Such cooperation is likely, however, to be of a non-binding, facilitative and flexible nature.

Suggestions
Actions to reduce household air pollution in developing countries should also help to achieve important SDG targets (Table 1). Implementation of the WHO indoor air quality guidelines on household fuel combustion is strongly recommended and requires WHO to provide strong technical support to countries through their regional and country offices.

This will help achieve a very important health-related SDG target (3.9). It is within the mandates of environmental protection agencies in these countries to lead the implementation process but the involvement of all stakeholders, including communities, and academic and research institutions, is required. Governments should Endeavour to adequately resource these agencies to effectively take up the task, and in countries where no such agencies exist, they should be supported by development partners to establish an agency.

Finally, effective promotion and dissemination of improved cook stoves is also recommended. This requires the formation of country alliances for clean cook stoves to seek the engagement of all stakeholders including manufacturers and users and provide a platform for sharing ideas, addressing concerns and collectively setting sector-wide goals and targets. An important forest conservation target (SDG 15.2) will be promoted through implementation of this recommendation. End-Notes:

1. https://onlinelibrary.wiley.com/doi/full/10.1111/reel.12223#reel12223-note-1001_2
2. Bonjour S, Adair- Rohani H, Wolf J, Bruce NG, Mehta S, Prüss- Ustün A, Lahiff M, Rehfuess EA, Mishra V, Smith KR Environ Health Percept. 2013 Jul; 121(7):784-90.
3. US Environmental Protection Agency and the US Consumer Product Safety Commission. The inside story: a guide to indoor air quality. Washington, DC: US Environmental Protection Agency and the US Consumer Product Safety Commission, Office of Radiation and Indoor Air; 1995. Document #402-K-93-007. Available from URL: http://www.epa.gov/iaq/pubs/insidest.html
4. WHO indoor air quality guidelines: household fuel combustion. Geneva: World Health Organization; 2014. Available from: http://www.who.int/indoorair/guidelines/hhfc/en/
5. http://ec.europa.eu/health/index_en.htm
6. Organization for Economic Co-operation and Development (OECD), The Economic Consequences of Air Pollution (OECD 2016)
7. European Environmental Agency (EEA), 'Air Quality in Europe - 2016 Report', EEA Report No 28/2016 (EEA 2016) 6.
8. Breathe Life campaign, which is a global joint campaign led by the WHO, the United Nations Environment Programme (UNEP) and the Climate and Clean Air Coalition (CCAC) to mobilize immediate action to tackle air pollution;
9. Lim SS, Vos T, Flaxman AD, Danaei G, Shibuya K, Adair-Rohani H, et al. A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet. 2012. December 15;380(9859)
10. Chafe ZA, Brauer M, Klimont Z, Van Dingenen R, Mehta S, Rao S, et al. Household cooking with solid fuels contributes to ambient PM2.5 air pollution and the burden of disease. Environ Health Perspect. 2014. December;122(12)
11. McCracken JP, Wellenius GA, Bloomfield GS, Brook RD, Tolunay HE, Dockery DW, et al. Household air pollution from solid fuel use: evidence for links to CVD. Glob Heart. 2012. September;7(3)
12. Noubiap JJ, Essouma M, Bigna JJ. Targeting household air pollution for curbing the cardiovascular disease burden: a health priority in Sub-Saharan Africa. J Clin Hypertens (Greenwich). 2015. October;17(10)
13. Smith KR, Bruce N, Balakrishnan K, Adair-Rohani H, Balmes J, Chafe Z, et al.; HAP CRA Risk Expert Group. Millions dead: how do we know and what does it mean? Methods used in the comparative risk assessment of household air pollution. Annu Rev Public Health.
14. Amegah AK, Quansah R, Jaakkola JJK. Household air pollution from solid fuel use and risk of adverse pregnancy outcomes: a systematic review and meta-analysis of the empirical evidence. PLoS One. 2014;9(12)
15. Sapkota A, Zaridze D, Szeszenia-Dabrowska N, Mates D, Fabiánová E, Rudnai P, et al. Indoor air pollution from solid fuels and risk of upper aerodigestive tract cancers in central and eastern Europe. Environ Res. 2013. January;120:90-5
16. Po JY, FitzGerald JM, Carlsten C. Respiratory disease associated with solid biomass fuel exposure in rural women and children: systematic review and meta-analysis. Thorax. 2011. March;66(3)
17. Oluwole O, Otaniyi OO, Ana GA, Olopade CO. Indoor air pollution from biomass fuels: a major health hazard in developing countries. J Public Health. 2012
18. World health statistics 2012. Geneva: World Health Organization; 2012. Available from: http://www.who.int/gho/publications/world_health_statistics/2012/en/index.htmlError! Hyperlink reference not valid.
19. Martin WJ 2nd, Glass RI, Balbus JM, Collins FS. Public health. A major environmental cause of death. Science. 2011. October 14;334(6053)
20. Clark ML, Peel JL, Balakrishnan K, Breysse PN, Chillrud SN, Naeher LP, et al. Health and household air pollution from solid fuel use: the need for improved exposure assessment. Environ Health Perspect. 2013. October;121(10)
21. Holm A, Blodgett L, Jennejohn D, Gawell K. Geothermal energy: international market update. Washington: Geothermal Energy Association; 2010
22. Financing renewable energy in developing countries: drivers and barriers for private finance in sub-Saharan Africa. Geneva: United Nations Environment Program Finance Initiative; 2012.
23. Decision 3/CP.17. Launching the Green Climate Fund. Bonn: United Nations Framework Convention on Climate Change; 2011.
24. Biogas BL. Practical action technical brief. Rugby: Practical Action; 2007. Available from: http://answers.practicalaction.org/our-resources/item/biogas
25. Khatavkar A, Matthews S. Bio-latrines. Practical action technical brief. Rugby: Practical Action; 2013. Available from: http://answers.practicalaction.org/our-resources/item/bio-latrinesError! Hyperlink reference not valid.
26. Barnes BR. Behavioural change, indoor air pollution and child respiratory health in developing countries: a review. Int J Environ Res Public Health. 2014. May;11(5)
27. Singh P, Sachs JD. 1 million community health workers in sub-Saharan Africa by 2015. Lancet. 2013. July 27 ; 382 (9889)