Global meat production has grown by 20 percent in the last decade and tripled since 1970, increases that have far exceeded the rate of population growth during the same periods and pose significant threats to the environment, the economy, and public health, a new report says. According to the Worldwatch Institute report, much of that growth is due to the rise of large-scale factory farming in developing countries such as China. Such industrial-scale farming not only poses health risks to livestock and ultimately introduces massive amounts of antibiotics into the environment, it also generates significant emissions of potent greenhouse gases, including methane and nitrous oxide, the report says. Earlier reports have found that livestock operations account for as much as 18 percent of the world’s greenhouse gas emissions. While the new report says people in the developed world consume more than twice as much meat as those living in developing nations (80 kilograms annually per person, compared with 32 kilograms), it predicts that demand for livestock products in sub-Saharan Africa and South Asia will nearly double by 2050.