Graham Brookes and Peter Barfoot
PG Economics Ltd., Dorchester, UK.

Genetically modified (GM) crops have now been grown com- mercially on a substantial scale for ten years. This paper assesses the impact this technology is having on global agricul- ture from both economic and environmental perspectives. It examines specific global economic impacts on farm income and environmental impacts of the technology with respect to pesti- cide usage and greenhouse gas emissions for each of the coun- tries where GM crops have been grown since 1996. The analysis shows that there have been substantial net economic benefits at the farm level amounting to $5 billion in 2005 and $27 billion for the ten year period. The technology has reduced pesticide spraying by 224 million kg (equivalent to about 40% of the annual volume of pesticide active ingredient applied to ara- ble crops in the European Union) and as a result, decreased the environmental impact associated with pesticide use by more than 15%. GM technology has also significantly reduced the release of greenhouse gas emissions from agriculture, which, in 2005, was equivalent to removing 4 million cars from the roads.

Key words: Yield, cost, income, environmental impact quotient, carbon sequestration, GM crops.