Microscopic particles that are part of our mix of air pollution are some of the most damaging because they avoid the natural filtering mechanisms of the body and settle far into the inner reaches of our lungs. The Clinton administration laid out rules to eliminate this danger, rules that were challenged by industry and ultimately upheld by the Supreme Court. Much of the country remains out of compliance, leaving it to the Bush EPA to push for further enforcement measures. I would be tempted to say, "Don't hold your breath." On the other hand, that may be the only thing you can do to stay safe!
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