Air Bags Trigger Breathing Woes
By Margaret Varnell, RN, RRT
Moments after the auto accident in July, 43-year-old Margo MacGhinty’s uttered, “Thank God for my airbag!” But within minutes her initial relief turned to fear. And then panic. Trapped inside her 1997 Jeep Grand Cherokee, MacGhinty was surrounded by a white cloud of swirling substances that burned her nose and mouth.
Unable to extricate herself from her vehicle, she could feel the burning sensation moving futher down the back of her throat and deeper into her chest. She could also feel the usual clamp-down that precipitates an asthma attack. Through it all, the door on the driver’s side was smashed in and she couldn’t escape the white cloud.
A state police vehicle was the first to arrive on the scene, and a cautious state patrolman did not dare to move her, even though MacGhinty begged him to get her out. There was no immediate danger of fire, so the fact that she was having difficulty breathing was secondary. The officer did not want to risk moving her and aggravating a possible spinal injury.
Paramedics arrived shortly thereafter, positioned a neck collar on MacGhinty and pried the door open. By that point, she had been breathing white cloud particles for approximately 17 minutes.
Later in the ambulance, she talked to paramedics about the fine white powder covering her upper body and clothes. EMTs confirmed the substance was from the airbag and that they often had heard accident victims complain of difficulty breathing and of experiencing a burning feeling in their noses, mouths, eyes and skin. One paramedic helped MacGhinty fish her rescue inhaler out of her purse and take three puffs.
She is still have breathing problems today and is threatening to file a lawsuit.
LOTS OF UNKNOWNS
It is difficult to say what exactly is launched into the atmosphere when an airbag deploys during a collision. There are several factors that come into play including the type of airbag, the type of inflator cartridge used, and the packing materials which allow the airbag to deploy. Studies have been done for sodium azide-based airbag systems, examining the gases used to inflate the bag. Sodium azide itself is consumed in the process of the bag’s deployment, leaving trace gases and byproducts. There have been no studies conducted on the dust and packing materials hurled into the immediate area when the bag deploys.
OSHA defines levels of contaminants and exposure restrictions for long-term instances of exposure. But these exposures are defined as eight hours or longer in length. There are no government standards or requirements that pertain to short-term, highly concentrated exposure events.
Most sodium-azide airbags are powered by nitrogen. A study published in 1995 by the Automotive Safety and Health Research Branch of General Motor’s North American Operations, Warren, Mich., found there were no “notable toxic gases in substantial concentrations” in deployment of driver’s side airbag systems.
But ASHRB researchers did note the presence of carbon monoxide, nitric oxide, ammonia, benzene, toluene, ethylbenzene, xylenes and a catch-all category of hydrocarbons (including methane, ethane, acetylene, and traces of larger aliphatic hydrocarbons). Breathing experts know that carbon monoxide and nitric oxide bind with hemoglobin and reduce PaO2. Ammonia is also a known irritant which precipitates pulmonary edema. Benzene has been linked to cancer; the remaining substances are toxic to the central nervous system in varying dose-dependent amounts.
There are two other studies presented in the literature, both also conducted by this research group. In a 1994 study of 24 asthmatics, the researchers found 10 asthmatics had “clinically significant bronchospasms” after a 20-minute passenger side exposure to a driver’s side airbag deployment. Four of these 10 individuals did not receive the full 20-minute exposure. Their bronchospams became so serious that they required intervention before the 20-minute test was completed. Researchers noted the gases measured were within “recommended guidelines” and concluded that there are no guidelines for particle exposure.
AIRBAG COMPOSITION
Airbags are packed with a talc-like powder that prevents the fabric from sticking to itself when deployed. And when deployed, an airbag hurls a considerable amount of dust, dirt and powder into an auto occupant’s face at speeds ranging anywhere from 50 to 200 m.p.h.
This material, which researchers classify as particulate matter, is the probable cause of asthmatic responses. It cannot escape notice that GM’s North American Division funded the studies submitted. This is not to cast shadows on researchers or this institution, but with 10 out of 24 subjects having “serious bronchospasms,” the obvious question centers on why no one else is studying this topic.
Automobile manufacturers are obviously fearful of litigation. Airbags have a potential to be figured in a class action suit. When MacGhinty contacted the Chrysler-Daimler Corp., its customer service representatives said they had heard of breathing problems related to airbag deployment but told MacGhinty to contact the airbag manufacturer to find out what gases, particles and gases may have been present. The airbag manufacturer responded by mailing her a one-page “Technical Data Sheet” that was last revised on Oct. 17, 1990. Both Chrysler-Daimler and the airbag manufacturer refused to return calls or to comment on the airbag matter.
Federal agencies are yet another story. In 1997, the National Highway Traffic Safety Administration with the assistance of the National Crash Analysis Center hosted a conference on Medical Indications for Air Bag Disconnection.
SUMMARY RESULTS
These are some of the results of the group’s executive summary:
COPD, emphysema and asthma were among potential issues raised: The byproducts of the propellant might precipitate severe bronchospasm in persons with lung disease, it was noted. The group recommend the manufacturer should not disconnect air bags for patients with these chronic lung diseases.
In further discussion, participants noted there is no risk of oxygen deprivation during air bag deployment because of the quick deflation of the device. There is some equivocal evidence to suggest that chemical irritants produced may precipitate bronchospasm in persons with asthma. However, there is no evidence to suggest this phenomenon is occurring with any greater frequency in the presence of air bags.
There is no reason to suspect persons with any type of chronic lung disease will be adversely affected by an air bag deployment sufficiently enough to justify disconnection of the device, the group argued. As with other conditions, the benefits of air bags in these situations outweigh the risks.
Benefits still outweigh the risks, according to a report to Congress earlier this year. Nontheless, shouldn’t there be a warning somewhere to the 22 million Americans with pulmonary disease?
As for the National Highway Traffic Safety Administration, a memorandum dated Oct. 21, 1991, outlined airbag safety discussions with GM, Chrysler, and Ford representatives
“All the manufacturers agreed with NHTSA’s concern that the potential for bad press on these few cases could cause a lot of harm to the public’s positive perception and receptiveness to air bags and that NHTSA/industry needs to work together to share information and develop a statistical basis of understanding,” that document noted.
The document then discussed each manufacturer’s knowledge of fatalities associated with airbag deployment and specific makes of cars involved. The memorandum noted GM had investigated 12 cases of asthmatic responses and that two to three of these were nearly fatal. They concluded there is no exposure problem to individuals immediately exiting the vehicle. Those trapped inside a vehicle until they can be extricated by EMTs may have an exposure problem.
Neither Ford nor Chrysler is reported to have commented on asthmatic responses to airbag deployments in this memorandum.
OTHER PROBLEMS
In addition to asthmatic complications, there are other problems like head and neck trauma and ocular injuries associated with airbag deployment. Trauma injuries are believed to be related to the speed of the airbag deployment. Some cases of right atrium trauma, pulmonary contusions, and pneumothorax are also included in this category. The ocular injuries are the result of alkali burns from the gases and particles blown into the eyes.
The NHTSA estimates that airbags have saved the lives of 2,474 drivers between 1986 and 1998. With their widespread incorporation into passenger cars, the agency estimates airbags will save 3,000 lives per year. Their benefits may far outweigh their risks. At the same time, airbag injuries are reported in 43 percent of all deployments.
It seems reasonable to request that drivers and passengers of vehicles equipped with airbags should be told of risks associated with air bags. Margo MacGhinty thinks so.
Margaret Varnell, Atlanta, is a freelance writer and practitioner.
References
Available on request.
