Is buying organic foods worthwhile? (idea)

Organic farming does decrease¹ yield to some extent, but there are organic methods that can be used to organically achieve yields nearly as high as conventional methods. Anyway, I just thought I'd provide some info on pesticide use, chemical fertilizers, and organic farming:

• Use of organic fertilizer could, according to various studies, reduce CO₂ (a greenhouse gas) emissions by up to 50% through less respiration and lowered energy use.
• The EPA has documented contamination of groundwater by pesticides in 38 states. (But keep in mind that organic != no toxic pesticides.)
• Run-off of pesticides can contribute to pollution. (So can organic pesticides, though.)
• Pesticide treadmill

"Certified Organic" is probably a poor marker for "environmentally friendly", and worse for "healthy". If you want your diet to be more environmentally friendly, you should probably consider eating less meat and perhaps buying locally-grown food.

¹ When I wrote this initially, I said 'increase'. Surely that's a typo.