Heavy smog in New Delhi
Prof Mark Sutton opens the World Environment Day seminar on nitrogen

Governments, industries and farmers across the world must join together to tackle the ‘major unsolved challenge’ of nitrogen pollution, an international seminar led by a Centre for Ecology & Hydrology scientist has heard.

The session, Nitrogen: Joining up for a Cleaner Environment, was held in New Delhi on June 4 a day before World Environment Day, an annual event overseen by UN Environment that is being hosted by India this year.

It was chaired by CEH environmental physicist Prof Mark Sutton, who is also director of INMS (International Nitrogen Management System), a UN-backed global coalition of scientists and institutions ­which aims to fight pollution by promoting better management of the nitrogen cycle. The panel at the session in New Delhi also comprised scientists, Indian government ministers and other stakeholders.

Opening Nitrogen: Joining up for a Cleaner Environment, Prof Sutton, pictured, explained there were many benefits of good nitrogen management. He said: “By joining up across the nitrogen cycle we aim to combine the environmental and economic arguments that will help mobilise governments, farmers and industry to manage the world’s nitrogen more effectively.”

Nitrogen poses multiple threats to human health and the environment, as it is simultaneously contributing to poor air and water quality plus climate change. Some 80% of the nitrogen from fertilizers and manure is lost to the atmosphere and water courses, which is compounded by emissions from vehicles and factories.  Added up, these flows cause a cocktail of worsening nitrogen pollution.  

Nitrogen is the largest fraction of PM2.5 (particulate matter) air pollution that gets deep in to lungs and contributes to cardiovascular and respiratory illness, while in drinking water it increases the risk of cancer.

Nitrogen pollution through the air, water and soil is also a major cause of loss of biodiversity. For example, it stimulates growth of certain plantlife such as rough grasses at the expense of more sensitive species with a high conservation value and also increases algal blooms, which cause the death of fish by reducing oxygen levels in water.

Despite all this, there has been little global action to tackle the problem, said Prof Sutton. hile the problem and effects of pollution from vehicle emissions on air quality, human health and climate change is widely known, the impact of nitrogen pollution from agriculture has been less well publicised.

As part of his efforts to make India more environmentally friendly, prime minister Narendra Modi has asked the country’s farmers to cut consumption of nitrogen-based fertilizers by half by 2022. Prof Sutton suggested that in addition to reduced use of such fertilizers by farmers across the world, there should also be more effective recycling of existing nitrogen sources such as excrement.

Meanwhile, in industry, a huge nitrogen resource is lost when nitrogen oxides from combustion are emitted to the atmosphere, exacerbating air pollution. Prof Sutton advocates improving methods to recapture nitrogen oxides and turn them into nitrates, which could be used by the chemical industry for uses such as fertilizer.

Prof Sutton said: “Everyone knows about climate change and carbon footprints, but how many people are aware that nitrogen pollution is just as significant? Different experts have focused on different parts of the nitrogen story and few have investigated how all the issues fit together. 

“Addressing the nitrogen challenge therefore requires us to pool our technical expertise and, due to the trans-boundary nature of nitrogen pollution, international co-operation is also essential if we are to make substantial progress. We must build on joint endeavours, such as INMS, while learning from the international experience of others.”   

The session concluded with the following:

  • More scientific evidence is needed for better understanding of the scale of the impacts of nitrogen pollution.
  • Evidences should be translated to a form that the public can understand. Therefore, the Indian Nitrogen Group is encouraged to work with NGOs (non-governmental organisations) to produce a public summary of the Indian Nitrogen Assessment, for a broad consensus and understanding.
  • Zero Budget Natural Farming (ZBNF) look promising also from the point of view of nitrogen. However, it need further validation and testing for improving performance.
  • There is a huge opportunity for India and South-Asia to take the lead in bringing the draft Nitrogen Resolution to the UN Environment Assembly. 


Additional information:

The panel for the session Nitrogen: Joining up for a Cleaner Environment, held as part of a World Environment Day dialogue series at the Vigyan Bhavan, New Delhi, on June 4 comprised:

  • Prof Mark Sutton of the Centre for Ecology & Hydrology, UK
  • Prof Nandula Raghuram, president of the Indian Nitrogen Group, which is made up of the country’s nitrogen researchers. He is dean of Biotechnology at the GGS Indraprastha University.
  • WWF International president Pavan Sukhdev
  • Bharathi Sivaswami Sihag, secretary of the Indian national government’s Department of Fertilizers
  • Vijay Kumar, senior adviser and head of the Zero Budget Natural Farming Programme for the Indian state of Andhra Pradesh.
  • Dr Mohammad Khurshid, director general of the South Asia Co-operative Environment Programme (SACEP), an inter-government organisation that promotes and supports protection, management and enhancement of the environment in the region.
  • Urmi Goswami, journalist at The Economic Times, an English language daily newspaper based in New Delhi. 


International Nitrogen Management System (INMS)


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