Bug spray can be a potential danger in the skies. It is required on some planes to kill insects coming in and out of other countries.

"People may not realize that before they board an aircraft, it may have been sprayed heavily with pesticides," said Judith Murawski of the Association of Flight Attendants.

Murawski, who is an expert in air safety, says pesticides pesticides are being sprayed in planes to keep insects from crossing borders, but what is designed to kill the bugs could be harmful to humans.

"They have damage to the optic nerve, to their brain, to their nerves they suffer from disabling fatigue - memory problems," said Murawski.

Pilots have reported short-term memory loss and confusion. In fact, since Aug. 2000, pesticides have been blamed for flight crew illnesses on more than 300 flights.

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"In many of the cases, the flight attendants are simply unable to work having worked regularly in a pesticide-soaked environment," said Murawski.

Some passengers have complained of burning skin and eyes, tremors and difficulty breathing.

Sometimes, the chemicals are even sprayed over passengers after the airplane is sealed.

"And then they walk down the aisle spraying over passengers heads," said Murawski.

But aviation expert George Novak says passenger risk is low.

"Day to day fliers shouldn't be overly concerned about it. Flight attendants have to be concerned because they are continually exposed to these different pathogens or irritants or substances that may be in the aircraft," said Novak.

We tried to talk to the airline industry about the dangers of pesticides and individual airlines about their pesticide policies, but no one would talk to us.

Meanwhile, unions representing flight attendants are pushing for non-chemical alternatives to keep damaging insects off planes and the Department of Transportation is starting to look at the pesticide issue very closely.