When Cows Pollute More Than Cars

In California's San Joaquin Valley, air-quality regulators are squaring off against the area's lucrative dairy industry over cow gas: Each dairy cow in the valley emits nearly 20 pounds of volatile organic compounds (VOCs) a year, according to official estimates. (Sadly, more of the gas comes from burps than flatulence, sharply lowering humor emissions.) VOCs combine with other pollutants to cause ground-level ozone, and with 2.5 million bovines and counting in the valley, that makes cows -- not cars, trucks, or pesticides -- the leading cause of smog. Officials may require emission-control measures at feedlots and waste lagoons, and are considering regulating cow chow to control the animals' gassiness. Noting the area's high rates of childhood asthma, one eco-justice advocate calls the situation "a public health crisis." And community activist Tom Frantz says regulations can't come fast enough: "Our lungs will not become an agricultural subsidy."

Thanks to Grist Magazine