The developing surge in global demand for biofuels poses a threat to food security both on a global and a local level. As demand increases, staples such as corn and wheat may be forced to compete with biofuels for agricultural inputs such as land, water, and pesticides.

There's a good article on this by Chris Goodall, author of How to Live a Low-Carbon Life, in his Carbon Commentary blog.

And Oxfam is quoted in a Guardian article reporting on this week's announcement by the UN World Food Programme that it no longer has enough money to keep global malnutrition at bay this year in the face of a dramatic upward surge in world commodity prices. Biofuels are again mentioned as one of the contributing factors. Oxfam's concern is the danger of malnutrition in the poorest countries, where 50%-80% of income goes on food.