Proving Chemically Induced Asthma Symptoms:

Reactive Airways Dysfunction Syndrome, A New Medical Development

By Richard Alexander

Five years ago patients and clients who associated adult onset asthma with chemical exposure found they were unable to prove medical causation and were precluded from pursuing their right to recover for significant injuries caused by others.

This is no longer the case as a result of 1985 medical research by Brooks and others identifying a new illness which is virtually identical to asthma, can persist for years, and is caused by exposure to chemical irritants.

Understanding this medical development is important for both plaintiff personal injury attorneys, as well as workers compensation lawyers, because victims of chemical exposures who suffer asthmalike symptoms can now prove how they were injured by a chemical.

Occupational Asthma

For years medical researchers have documented asthmalike conditions in firefighters precipitated by smoke. Certain occupations have been known to be associated with asthmalike responses: polyurethane foam workers exposed to isocyanates, laboratory workers exposed to formaldehyde, meat wrappers working with polyvinyl chloride soft wrap film and heat activated price labels, electronic fabricators who solder, and metal refiners working with nickel, cobalt, and chromium.

While these illnesses were clearly associated with certain occupations, proximate causation in the third party setting faltered because of the inability of medical experts to distinguish work and non-work related asthma and the inability to prove that a chemical caused the condition. Today physicians can identify certain asthmalike conditions as being caused by chemical exposures.

Reactive Airways Dysfunction Syndrome

This newly defined illness, known as RADS or reactive airways dysfunction syndrome, is identical to asthma, but is induced by chemical exposure. Individuals with RADS have difficulty breathing, continuing cough, wheezing, and shortness of breath. In all cases the condition occurs after only one exposure to a lung irritant and respiratory symptoms occur within twenty-four hours after exposure. Although many patients resolve within six months, some continue to be symptomatic for five years.

The criteria for confirming the diagnosis of RADS are:

1. Documented absence of preceding respiratory complaints.
2. The onset of symptoms occurred after a single specific exposure incident or accident.
3. The exposure was to a gas, smoke, fume or vapor that was present in a high concentration and had irritant qualities.
4. The onset of symptoms occurred within twenty-four hours after the exposure and persisted for at least three months.
5. Symptoms simulated asthma, with cough, wheezing and dyspnea predominating.
6. Pulmonary function tests may show airflow obstruction.
7. Methacholine challenge testing was positive.
8. Other type of pulmonary diseases were ruled out.

The major medical break through in making the RADS diagnosis is methacholine challenge testing, which confirms airway hyperresponsiveness. As a result, patients injured on-the-job or by third parties now have available a means of proof of injury, as the following important case study establishes. The diagnosis of RADS, while requiring correlation with the patient's clinical history can be supported by methacholine challenge testing and also through the use of peak expiratory flow rate measuring devices which can document a greater than 20% drop in peak flow over a twenty-four hour period and thereby confirm bronchospasm due to environmental and work place exposures.

Important Case Study

In 1991 Dr. David Kern reported an in-depth study of a 1988 spill of a gallon of acetic acid (100% vinegar) at a community hospital which exposed 56 members of the clinical staff. While other researchers have reported individual cases of RADS, "missing from all these reports, however, are control groups, validation of reported preexposure health status, assessment of dose- response relationships, and consideration of chance occurrence and methodologic bias."

Kern's study addresses these issues and lays the cornerstone of the scientific foundation for the reactive airways dysfunction syndrome.

In the acetic acid spill, an increasing risk of RADS was found at high acetic acid exposure levels. Eight workers developed asthmalike symptoms within twenty-four hours of the spill and nearly a year later four still met all the criteria for RADS. While acknowledging that the numbers reported are small, Kern concludes that his research supports "the presence of a dose-response relationship between acetic acid exposure intensity and persistent asthmalike symptoms with demonstrated airway hyperresponsiveness."

Plaintiffs Now Have Provable Claims

As a result of this medical development, whole new categories of plaintiffs now have provable claims.

For example, hospital employees working in endoscopy units have recently been identified as suffering from RADS due to exposure to glutaraldehyde, widely considered one of the best disinfectants for cold sterilization. For years doctors and hospital administrators have considered glutaraldehyde to pose little risk and it is normally used in unprotected, open environments. However, British researchers for the past several years have reported that methacholine challenge testing confirms a definite association between glutaraldehyde exposure and respiratory symptoms. As a result, one manufacturer's disclosure on its Material Safety Data Sheet [that 2 per cent glutaraldehyde can be categorized as merely an inhalation irritant that can be safely used without ventilation] clearly fails to warn of the known dangerous propensities of this product.

Conclusion

To lose the ability to enjoy clear breathing is a major, significant and life threatening injury. Thanks to recent developments medical science can now identify necessary precautions for using chemicals and products once thought to be safe. In addition, these developments now provide juries with the ability to legally hold accountable manufacturers and sellers who neglect to properly warn the public concerning their product's hazards. The criteria listed above for making the diagnosis of RADS is equally important to lawyers representing victims of RADS as an important checklist for proving chemically induced injury and for ruling out asthma of unknown origin. Defendants will continue to claim that survivors of chemical exposure suffer from a pre-existing tendency, but with current medical knowledge the combination of clinical history and exposure allows well-trained physicians to make the diagnosis of RADS.

Endnotes

[1] San Jose attorney Richard Alexander, a 1969 National Honor Scholar from the University of Chicago Law School is a former member of the Board of Governors of The State Bar of California. The Alexander Hawes, LLP specializes in negligence, chemical, aviation, defective product and consumer fraud cases. The firm is committed to professional and public education on legal and safety issues through publishing in professional journals and newspapers and by participating in seminars and conferences. Copyright 1992-2004 By Richard Alexander.

[2] Brooks, S.M., Weiss, M.A., Bernstein, I.L. Reactive Airways Dysfunction Syndrome After High Level Irritant Exposures, Chest, 1985, 88:376-84.

[3] Kern, David G. Outbreak of the Reactive Airways Dysfunction Syndrome after a Spill of Glacial Acetic Acid. Amer. Rev. Respir. Dis. 1991, 144:1058-1064.

[4] Harkonen, H., Hordman, H. Korhonen, O. Winblad, I. Long-Term Effects of Exposure to Sulfur Dioxide: Lung Function Four Years After a Pyrite Dust Explosion. Amer. Rev. Respir. Dis. 1983, 128:890-3.

[5] Parks, W.R. Occupational Lung Disease, Butterworth, 1987.

[6] Ibid.

[7] See for example Large, A.A., Owens, G.R., Hoffman, L.A. The Short-Term Effects of Smoke Exposure on the Pulmonary Function of firefighters. Chest 1990, 97:806-09. Sherman, C.B. Barnhart, S. Miller, M.F. Firefighting Acutely Increases Airway Responsiveness. Amer. Rev. Respir. Dis. 1989, 140-185-90. Boulet, L.P. Increases in Airway Responsiveness Following Acute Exposure to Respiratory Irritants: Reactive Airway Dysfunction Syndrome or Occupational Asthma? Chest, 1988, 94:476-81. Luo, J.C. Nelsen, K.G. Fischbein, A. Persistent Reactive Airway Dysfunction Syndrome After Exposure to Toluene Diisocyanate. Br. J. Ind. Med. 1990, 487:239-41. Alford, P.T. McLees, B.D. Case, L.D. Reactive Airways Dysfunction Syndrome in Workers Post Exposure to Sulfur Dioxide. chest 1988, 94:875. Promisloff, R.A. Phan, A. Lechner, G.S. Cichelli, A.V. Reactive Airways Dysfunction Syndrome in Three Police Officers Following a Roadside Chemical Spill. Chest 1990, 98:928-9.

[8] Kern, 1063.

[9] Kern, 1062.

[10] Corrado, O.J., Osman, J. & Davies, R. J. Asthma and Rhinitis After Exposure to Glutaraldehyde in Endoscopy Units. Human Toxicol., 1986, 5:325- 27. See also Jachuck, S.J., Bound, C. L., Steel, J. and Blain, P. G. Occupational Hazard in Hospital Staff Exposed to 2 per cent Glutaraldehyde in an Endoscopy Unit. J. Soc. Occup. Med. 1989, 39(2): 69-71; Burge, P.S. Occupational Risks of Glutaraldehyde. British Medical Journal 1989, August 5, 299(6995): 342.

© Richard Alexander, 1992.

Alexander Hawes, LLP is a California law firm that specializes in personal injury, wrongful death, and financial losses caused by negligence, defective products, toxic chemicals, corporate misconduct or insurance fraud on behalf of consumers, small investors, injured workers and small businesses. In addition to individual cases the firm prosecutes class actions for large groups of individuals who have suffered financial loss as a result of corporate fraud, defective consumer products, and environmental pollution. The firm holds Martindale-Hubbell's highest rating and is recognized in the List of Preeminent Law Firms in the U. S.

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