The new hazards of air shipping. (includes related articles on the FAA's effort to educate shippers and carriers on dangerous goods transport and shippers' emphasis on training workers on handling hazardous materials)

If there is more attention and regulation of dangerous goods than ever, why are some questionable shipments getting onto airplanes and who will pay to keep them away?

After more than a year-and-a-half of industry hand-wringing and regulation, incidents such as the one aboard American Airlines Flight 931 last month were not supposed to happen. But as 46 passengers settled in for the flight from Miami to Quito, Ecuador, early in the evening of Oct. 1, a bag of corrosive pesticides fell from a conveyer belt, spilling the contents and enveloping the 757 in noxious dust.

Five people complained that they had inhaled the substance, which the Federal Bureau of Investigation said was a powder chemical called Dowicide A that can eat through metals and cause blindness and severe skin burns.

A spokeswoman for American said two loading employees were taken to the hospital as a precaution and that no passengers were injured.

The shipment was sent by Miami-based forwarder Executive Freight Consolidators, according to investigators. The FBI alleges that Angel Fuentes, president of Executive Freight, hired courier PABS Trading to ship 10 50-pound bags of the powder as excess passenger baggage with the manufacturer's warning labels concealed under plastic. The PABS courier checked in with more than 20 bags of luggage, according to American Airlines. The U.S. Attorney in Miami has charged Fuentes with knowingly shipping an illegal hazardous material. He faces up to five years in prison if found guilty.

Three weeks later, while a joint task force of 60 government agents from the FBI, the Federal Aviation Administration and the Department of Transportation raided the AA terminal in Miami, government regulators were deciding on a safety advisory concerning air courier operations and excess baggage procedures.

Although the reason for the FBI search is in a sealed warrant, AA spokeswoman Martha Pantin said agents walked away with several documents from American's files. "We were surprised and we are cooperating and we have nothing to hide,' she said.

While confusion reigned in Miami, there has been one rather simple question hanging over the meetings in Washington between government regulators and the airline industry: doesn't anyone remember Valujet Flight 592?

The May 11, 1996 crash of a Valujet DC-9, which investigators believe was caused by improperly packed and shipped oxygen canisters, killed 110 people and focused national attention on the shipping of hazardous materials in the air cargo industry.

"I don't know how long this kind of shipping has been going on" Anne Figueiras, an FBI agent working on the Fuentes case, said of the Miami incident. "It behooves everyone to make sure that a Valujet doesn't happen again. …