Ozone helps shield people, animals and crops from damaging ultraviolet rays from the sun. Much of the concern about the ozone layer has focused on Antarctica, where a seasonal hole, or thinning, has been seen for two decades, and the Arctic, where a hole was observed last year. But those regions have almost no population.
Research in the 1970s uncovered the link between CFCs and damage to the ozone layer, and these refrigerant gases are now banned. The use of CFCs, or chlorofluorocarbons, was phased out beginning in the late 1980s with the signing of an international treaty called the Montreal Protocol, but it will take decades for them to be cleansed fully from the atmosphere. It is chlorine from the CFCs that ultimately destroys ozone, upsetting what is normally a balanced system of ozone creation and decay. The chlorine has to undergo a chemical shift in the presence of sunlight that makes it more reactive, and this shift is sensitive to temperature.
Strong summer thunderstorms that pump water high into the upper atmosphere pose a threat to the protective ozone layer over the United States. The risk of ozone damage could increase if global warming leads to more such storms. A thinning of the ozone layer over the US during summers could mean an increase in ultraviolet exposure for millions of people and a rise in the incidence of skin cancer and cataracts.
If CFCs had not been banned, the ozone layer would be in far worse shape than it is. But by showing that CFC-related ozone destruction can occur in conditions other than the cold ones at the poles, a new study suggests that the full recovery of the ozone layer may be further off than we thought.
We don't want to lose our ozone, but maybe that ozone hole isn't all bad: Young, healthy adult volunteers exposed for two hours to ozone developed the type of physical changes that lead to heart attacks. The changes were temporary and reversible in these young, healthy participants, but longer exposure for more vulnerable people might lead to permanent damage.
PhysOrg.com quotes researcher Robert B. Devlin as saying, "This study provides a plausible explanation for the link between acute ozone exposure and death." The participants didn't feel any symptoms, but the changes were definitely there. This could be one of the reasons that people tend to overlook the ozone problem. "People can take steps to reduce their ozone exposure, but a lot of physicians don't realize this," Devlin says.
The World Health Organization estimates that 2 million people worldwide, mostly elderly people with cardiovascular disease, die because of acute exposure to air pollution. The EPA puts the yearly US toll at 40,000-50,000 deaths.
In the July 27th edition of the New York Times, Henry Fountain quotes atmospheric researcher James G. Anderson as saying, "The world said, 'Oh, we've controlled the source of CFCs; we can move on to something else." But the destruction of ozone is far more sensitive to water vapor and temperature."
There's not much you can do about the ozone hole, but you CAN do something about the two biggest health problems in the US today: smoking and obesity. We can't help you with the first one, but we CAN help you lose weight because (just in time for bathing suit season) we've put Anne Strieber's famous diet book ON SALE.: We've REDUCED THE PRICE to $2.99, which is $2 off the former price of $4.99!