Concern over air pollution has traditionally been focused on urban situations. Fresh evidence from a study by an Imperial College research team, the International Institute for Environment and Development (IIED) and research partners in India and Pakistan, suggests that air pollution from cities could have a significant impact on agricultural production and livelihoods in less developed countries. It is likely that ground level ozone, sulphur dioxide and nitrogen dioxide are already affecting crops in many peri-urban areas. The researchers warn that official policies aimed at increasing crop yields and food security could prove ineffective unless they take pollution factors into account and prescribe pollution prevention or reduction measures. Their risk assessment focuses on India, where they identify innovative pollution assessment and reduction measures that represent a departure from the orthodox command-and-control approach to Clean Air regulations and policies.

Recent changes in the pattern of air pollution emissions may have impacts on rural livelihoods in peri-urban neighbourhoods. Rapid urban population growth and expansion of heavy industrial development may spell trouble for agriculture. Conventionally, analysis of pollution problems has been narrowed down to primary pollutants in relation to the health of city dwellers. Analysis of the impact of primary and secondary pollutants on agriculture reveals three potentially significant dangers: direct visible harm to crops, direct invisible effects on growth and yield, and indirect effects such as pest 'breakthroughs'.

Evidence of ozone damage to a wide array of crops has been recorded throughout the US and Europe. But with the notable exception of sulphur dioxide, relatively little empirical knowledge exists about the effects of specific airborne pollutants on agriculture and rural livelihoods in developing countries. Integrated risk assessment models are needed and they should take various interconnected factors into account, including climatic variables, variation between crop varieties and interactivity among insect pests and pathogens. More evidence-based field research in potential 'at-risk areas' is also needed to establish the severity of the problem. Yield losses need to be better estimated, dose-response relationships developed, and ambient air quality standards established for ozone. In response to these growing concerns, a new multidisciplinary project has been launched to assess the extent of the problem in India. Combining policy and research, it will:

• Introduce participatory appraisals to harvest farmers' perceptions of air pollution and assess its importance as a factor in peri-urban agriculture involve stakeholders in the quantification of yield losses, and evaluation of policy implications.
• Develop professional forums for exchanging and disseminating information and views on pollution and agriculture

Source(s):
A Hidden Threat to Food Production: Air Pollution and Agriculture in the Developing World. IIED Gatekeeper Series, no. 73, Marshall F., Ashmore M. and F. Hinchcliffe (1997) >

Funded by: Environment Research Programme, DFID, UK

id21 Research Highlight: 1998-Apr-18

Further Information:
Fiona Marshall or Mike Ashmore
Imperial College Centre for Environmental Technology
Silwood Park
Ascot
Berkshire
SL5 7PY
UK

Tel: +44 (0)1344 294213
Fax: +44 (0)1344 294339
Contact the contributor: F.Marshall@ic.ac.uk

Imperial College Centre for Environmental Technology, UK

Contact the contributor: M.Ashmore@ic.ac.uk

Other related links:
Gatekeeper series, International Institute for Environment and Development (IIED), UK