Each year, the U.S. releases more than 1.6 million metric tons of heat-absorbing greenhouse gases into the atmosphere. Of this amount, about 81 percent comes from the combustion of fossil fuels [...]

We usually think of automobiles and factories as the greatest sources of pollution. The Clean Air Act of 1970, revised in 1990, has succeeded in reducing certain outdoor emissions; however, a person’s exposure to some pollutants is far greater indoors than outdoors.
Girl painting fingernailsFor instance, fingernail polish releases much more formaldehyde (H2CO) than does the [...]

When Congress passed the 1990 amendment to the Clean Air Act, many people believed the problem of acid rain had been solved. The amendment called for 50 percent reductions in emissions [...]