Transgenic crops: hazards and uncertainties

New review from Brazilian Ministry of Agrarian Development highlights hazards and uncertainties of GM crops. The Brazilian Ministry of Agrarian Development (MDA) has published an important new book: “Transgenic crops hazards and uncertainties: More than 750 studies disregarded by the GMOs regulatory bodies”. It examines research showing hazards to human and animal health, as well as risks to the environment, and agronomic or socioeconomic problems. To take an example of the kind of scientific publication neglected by risk assessors, but which this book highlights, a study from China shows how GM Bt cotton failed to reduce insecticide sprays, even though this is the supposed advantage of Bt crops. The study examined the effects of pesticide applications on pests (aphids and acarid mites) and predators (ladybeetles and spiders) in both GM Bt insecticidal cotton and non-GM cotton. The study found that Bt cotton did not cause changes in populations of acarids, while its effects on aphids were inconsistent. Although insecticides were not applied against the main pest, cotton bollworm, on GM Bt cotton, the total number of insecticide applications in three years was no less than the total applied on non-GM cotton. The study concluded that “the use of Bt cotton should be evaluated carefully in China”. A separate study from India examined the costs and returns from the cultivation of different types of cotton in a rainfed village in the Vidarbha region of Maharashtra. Expenditure on chemical pesticides was higher for Bt cotton than for other varieties of cotton. Variability in production was also higher for Bt cotton than for other types of cotton.