Dear EarthTalk: What is the significance of the recent discovery of a cow in Alabama having Mad Cow disease? Isn't that the very first in North America? Should we be worried?
—Chris Carroll, Austin, TX
Actually, Mad Cow Disease, technically known as Bovine Spongiform Encephalopathy (BSE), was first detected in North America in January 1993, when a beef cow that had been imported from Britain to the Canadian province of Alberta tested positive. The Canadian government destroyed that particular cow, as well as its entire herd, in order to quell the potential spread of the disease.
Federal agricultural agencies in both Canada and the United States then stepped up testing for BSE coast-to-coast while imposing stricter import criteria for cows coming in from abroad. And since the disease spreads not from direct cow-to-cow contact but only through consumption of infected feed, both countries banned rendered cow remains from being added to cattle feed beginning in 1997.
The redoubled efforts seemed to pay off, as another case of BSE didn't show up in North America for a decade. But then in May 2003, veterinary officials in Alberta confirmed another case, but this time involving a cow born in Canada. Seven months later, American officials announced the first case of BSE in the U.S., when the remains of a deceased cow from a farm in Washington State tested positive.
Regulators feared that some meat may have made its way into supermarkets, which in turn sparked a wave of mad cow hysteria, including import bans on American beef by some foreign countries. Records showed that the cow had been born in Canada, leading to cross-border finger pointing. But when the disease showed up in a Texas cow in June 2005, and then again recently in an Alabama cow, Americans stopped blaming Canada and began looking to stem the spread of the disease within U.S. borders.
BSE, a fatal disease of the nervous system of cattle, first appeared in the United Kingdom in the mid-1980s and then spread across Europe, peaking at almost 1,000 new cases per week in 1993. In 1996, variant Creutzfeldt-Jakob Disease (vCJD), an offshoot of BSE, was detected in humans and linked to the eating of meat and cattle products contaminated with BSE. Fewer than 200 cases of vCJD, all originating in Western Europe, have been detected since the human disease was first identified.
Despite assurances by both Canadian and U.S. officials that BSE cases in recent years have been isolated ones and that North American beef is fit for human consumption, some skeptics aren't so sure. "This disease is endemic in U.S. herds," says News Target health and wellness columnist Mike Adams. "It is circulating in cows right now and there are almost certainly cows infected with mad cow disease that are being slaughtered and used in the human food supply," he adds. Adams is worried that the millions of Americans who eat red meat every day are putting themselves at risk while the government focuses on spinning the story to stifle valid concerns.
CONTACTS: Health Canada BSE Information, www.hc-sc.gc.ca/fn-an/securit/animal/bse-esb/index_e.html; U.S. Department of Agriculture BSE Newsroom, www.aphis.usda.gov/newsroom/hot_issues/bse.shtml.
Dear EarthTalk: Can old tires be recycled? If so, where, and what is the recycled material used for?
—George, Rockville, MD
Old tires can indeed be recycled, and thanks to concerted efforts by state and provincial governments from coast-to-coast, as many as 80 percent of them are these days across North America. While some of these old tires are remanufactured into new tires, others are used in a wide variety of applications including railroad ties, rubber-modified asphalt, athletic surfaces, insulation, plastic/rubber blends used in a variety of products, even fuel.
The world's first tires were made entirely out of natural rubber, but the Southeast Asian forests where the plants grew could only produce so much. By World War II most tires were composed primarily of synthetic rubber made from petroleum products. Up until the 1960s, tires were routinely recycled and broken down for use in making new tires. But when imported oil got cheaper, demand for recycled synthetic rubber fell, and caches of old tires with nowhere to go—most landfills won't accept them—began to sully landscapes across North America. These old tire stockpiles became havens for pests and mosquitoes, and would even occasionally burst into flames and belch noxious chemicals into the air.
Beginning in the mid-1990s, state and provincial governments in the U.S. and Canada led the charge in mandating and funding tire recycling efforts. In doing so they helped spur the markets for reprocessed synthetic rubber that exist today. Now thousands of companies across North America specialize in turning recycled synthetic rubbers into useful new products.
American consumers looking to offload old tires should take a gander at the U.S. Environmental Protection Agency's (EPA"s) "Management of Scrap Tires" website to find tire recycling centers near them. Canadians can turn to the website of the Canadian Association of Tire Recycling Agencies (CATRA) to find out where to take used tires in any province, including even the remote Yukon Territory.
The EPA also offers free Business Planning Guides for those who might be looking to start a tire recycling or re-manufacturing business. The website Scrap Tire News also provides a wealth of knowledge on different ways to get started.
Despite this encouraging progress, North America still faces a backlog of hundreds of millions of old tires, quickly piling up outside filling stations and in backyards near you. The EPA estimates that 290 million scrap tires are generated annually, representing two percent of all solid waste, and that some 265 million are sitting in stockpiles right now. At the very least, we could all take the advice of Participating in Nature: Thomas J. Elpel's Field Guide to Primitive Living Skills and turn our old tires into "sandals with a 50,000 mile warranty!"