U.S. Department of Labor Office of Workers’ Compensation Programs Washington, DC 20210

May 1, 2020

Dr. Steven Markowitz

Chair

Advisory Board on Toxic Substances and

 Worker Health

Queens College, Remsen Hall

65-30 Kissena Boulevard

Flushing, NY 11367

Dear Dr. Markowitz:

I am writing in response to your March 5, 2020, letter to the Department of Labor (Department)

regarding the recommendation made by the Advisory Board on Toxic Substances and Worker 

Health (Advisory Board) regarding a content edit to the Federal (EEOICPA) Procedure Manual 

(Version 4.0). 

The Advisory Board has recommended that the Department edit content to Exhibit 15-4 

Exposure and Causation Presumptions with Development Guidance for Certain Conditions. 

Specifically, the Advisory Board recommends making the following edit to Section 5c(ii) 

relating to asthma, that the bolded sentence be added and the sentence with the line through it be 

removed:

After a period of covered employment, a qualified physician conducts an 

examination of either the patient or available medical records and he or she 

concludes that the evidence supports the employee had asthma and that an 

occupational exposure to a toxic substance was at least as likely as not a 

significant factor in causing, contributing to, or aggravating the condition. 

The qualified physician must provide a well-rationalized explanation for 

his or her conclusions. The qualified physician must provide a well-rationalized 

explanation with specific information on the mechanism for causing, contributing 

to, or aggravating the conditions. The strongest justification for acceptance in 

this type of claim is when the physician can identify the asthmatic incident(s) 

that occurred while the employee worked at the covered work site and the 

most likely toxic substances trigger.

In its supporting rationale, the Advisory Board argues that physicians generally understand 

“mechanism of disease” to signify the cellular or physiological processes and mediators that 

cause disease. The Advisory Board further states that clinicians are unable to identify 

mechanisms for work-related illness, because clinical tools generally do not identify mechanisms 

of disease, and the mechanisms of work-related asthma remain poorly defined. 

After considering the Advisory Board’s recommendation, the Department agrees that the 

reference to a causal “mechanism” may add ambiguity for physicians regarding the evidence 

necessary to establish compensability for an asthma claim. The Department agrees to modify the 
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language by removing, “mechanism for causing, contributing to, or aggravating the condition.” 

However, in keeping with the explanation that the Department provided to the Advisory Board in 

a November 9, 2017, letter, the Department will make the following revision:

After a period of covered employment, a qualified physician conducts an 

examination of either the patient or available medical records and he or she 

concludes that the evidence supports the employee had asthma and that an 

occupational exposure to a toxic substance was at least as likely as not a 

significant factor in causing, contributing to, or aggravating the condition. 

The qualified physician must provide a well-rationalized explanation for 

this conclusion that identifies the toxic substance(s) that likely caused, 

contributed to, or aggravated the diagnosed asthma. The qualified 

physician must provide a well-rationalized explanation with specific information 

on the mechanism for causing, contributing to, or aggravating the conditions. The 

strongest justification for acceptance in this type of claim is when the 

physician can identify the asthmatic incident(s) that occurred while the 

employee worked at the covered work site and the most likely toxic 

substances trigger.

As the Department explained previously, it must obtain evidence that identifies the toxic 

substance that is the most likely trigger for the asthmatic event that forms the basis for the 

physician’s diagnosis of asthma, because the condition can only be accepted as a compensable 

“covered illness” if “it is at least as likely as not that the exposure to such toxic substance was 

related to employment a Department of Energy facility.” Reference 42 U.S.C. § 7385s4(c)(1)(A). Given this stipulation, the Department will make the aforementioned edit to 

communicate to claims staff more clearly the evidence required legally to establish 

compensability for asthma. 

On behalf of the Department, the Office of Workers’ Compensation Programs, the Energy 

program, and the communities we service, I look forward to the continued efforts of the 

Advisory Board.

Sincerely,

/s/

Julia K. Hearthway

Director

Office of Workers’ Compensation Programs