The question is which one and how much. There are conflicting reports from various news agencies.

Four year study: Genetically modified Bt maize does not harm earthworms even after several years of cultivation.

Growing cotton that has been genetically modified to poison its main pest can lead to a boom in the numbers of other insects, a ten-year study in northern China has found.

This one from a statistician

Critique no. 3 from Food Standards Australia New Zealand: FSANZ remains confident that the changes reported in these studies are neither sex- nor dose-related and are primarily due to chance alone.

Critique no. 2 of the French research findings safety concerns with 3 GM corn

Three types of Monsanto’s GM corn do have toxic effects on rats, according to recent research, but it remains to be seen if it holds up any better than previous studies.

The Bureau of Rural Sciences report, Plant gene technology: improving the productivity of Australian agriculture, released today.

China has approved its first strain of genetically modified (Bt) rice for commercial production.

PG Economics Ltd has, in quick time, posted a comprehensive critique of the Organic Centre’s recent report, “Impacts of genetically engineered crops on pesticide use: the first thirteen years” by Charles Benbrook.