Noteworthy Decision Summary
Decision: WCAT-2005-02493-RB Panel: Randy Lane Decision Date: May 13, 2005
Occupational disease – Presumption of causation in section 6(3) and Schedule B of the Workers Compensation Act – Rebuttable presumption – Meaning of “prolonged exposure” – Minimum required amount of exposure – Lung cancer – Aluminum smelting industry – Exposure to polycyclic aromatic hydrocarbons – Policy items #26.21 and #93.22 of the Rehabilitation Services and Claims Manual, Volume I – Rebutting presumption with medical literature – Extension of time to apply for compensation – Section 55 of the Workers Compensation Act
* For the purposes of policy item 4(e) of Schedule B to the Workers Compensation Act (Act), a worker’s exposure to a substance is “prolonged” when the exposure has exceeded a reasonable duration. Although the amount of the exposure must be greater than what would be received by an average person in their day-to-day life, there is no required minimum level of exposure. The exposure need not be continuous but must be frequent and ongoing.
* For the section 6(3) presumption to be rebutted there must be positive proof of another cause of the disease rather than merely a question as to whether the employment is the cause of the disease.
* In the absence of an amendment to Schedule B, it is not open to the Workers’ Compensation Board (Board) to rebut the section 6(3) presumption by asserting that the evidence in the medical literature does not, in fact, support the presumption.
* Although the widow applied for compensation more than 20 years after the death of the worker, special circumstances existed that precluded the widow from filing an application within one year after the worker’s death.
In this case, a widow applied for benefits more than 20 years after her husband died of primary lung cancer. The Board found it was more likely the worker’s lung cancer was caused by his having smoked cigarettes for approximately 25 years rather than as a result of working in an aluminum smelter for five years where he was exposed to polycyclic aromatic hydrocarbons (PAHs). The Board also found the widow’s claim was barred under section 55 of the Act as she had not filed for compensation within one year of her husband’s death. The widow appealed to the Workers’ Compensation Review Board (Review Board). On March 3, 2003 the Review Board and the Workers’ Compensation Appeal Division (Appeal Division) were replaced by the Workers’ Compensation Appeal Tribunal (WCAT). As this appeal had not yet been considered by the Review Board before that date, it was decided as a WCAT appeal.
The panel first addressed the widow’s delay in filing for compensation. The issue was whether there were special circumstances in the one-year period following the worker’s death, not whether special circumstances existed for all the years between the date of death and the date of application. The panel noted that a number of factors as to what constitutes “special circumstances” were frequently cited in previous Appeal Division decisions. These include:
* characteristics of the worker such as language difficulties, limited education, recent immigration or other factors which would create obstacles to understanding that there is a system of workers' compensation and how to access it;
* lack of knowledge that an injury or disease might be work related because of delayed onset of the condition, minor nature of the original injury, or failure to recognize that it is related to work; and
* reliance on the advice of others such as a physician or employer where the worker is dependent on such advice due to language difficulties, limited education, or other similar difficulty.
The panel found that, as a recent immigrant, the widow’s English skills were limited at the time of the worker’s death. Neither the worker’s employer nor his physician advised her that the worker’s lung cancer may have been caused by his work environment. Thus, special circumstances existed which precluded the widow from applying for compensation within one year after the worker’s death. As this was not a case where the passage of time significantly affected the Board’s ability to adjudicate the widow’s claim, the panel found the Board should exercise its discretion to adjudicate the claim.
The panel found that the worker’s death was due to the nature of his employment and his widow was entitled to benefits. Section 6(3) provides that if a worker at or immediately before the date of disablement was employed in a process or industry specified in Schedule B, and the worker contracted a disease identified in the Schedule as relating to that process or industry, the disease is deemed to have been due to the nature of that employment, unless the contrary is proven. The effect of item 4(e) of Schedule B is that the section 6(3) presumption applies to a worker “where there is prolonged exposure to particulate polycylic aromatic hydrocarbons” at work and the exposed worker develops “primary cancer of the lung”.
The panel analyzed the meaning of the word “exposure” in item 4(e) of Schedule B and concluded that it must refer to encountering PAHs at a level in excess of the day-to-day level we all may encounter. If the word “exposure” does not include some requirement involving the amount of PAHs encountered, then the presumption becomes meaningless.
The panel then examined the meaning of “prolonged”. As discussed in item #26.21 of the Rehabilitation Services and Claims Manual, Volume I, it refers to duration of exposure and “excessive” refers to amount of exposure. Thus, once a worker’s exposure has exceeded a reasonable duration, the worker has experienced “prolonged exposure”. Apart from the requirement that the exposure be greater than the amount a person would experience in their day-to-day lives, there is no requirement that the worker be exposed to a minimum level of exposure. To be prolonged, the exposure need not be continuous but must be frequent and ongoing.
“Prolonged exposure” is not determined by whether the worker’s exposure exceeds that declared in the medical and scientific literature to be associated with a doubling of the risk of developing the occupational disease. If it was, Schedule B would not serve the purpose for which it was designed because adjudication associated with subsection 6(3) would be little different from adjudication under subsection 6(1). The panel found that the worker’s five years of exposure to PAHs amounted to prolonged exposure to PAHs. Thus, the section 6(3) presumption applied.
The panel also found that the section 6(3) presumption was not rebutted. Item #26.21 provides that for the presumption to be rebutted the evidence must establish that it was something other than employment that caused the disease. The panel concluded that this requirement cannot be satisfied by asserting that the amount of exposure in the workplace was insufficient to have caused the disease and therefore something else must have been the cause. There must be positive proof of another cause of the disease rather than some question as to the adequacy of proof that employment is the cause of the disease.
The panel reviewed the opinion of a Board medical specialist who referred to a number of medical journal articles which questioned the existence of a strong relationship between employment in the aluminum smelting industry and lung cancer. The panel found that, in the absence of an amendment to Schedule B, it is not open to the Board to rebut the section 6(3) presumption by asserting that the medical literature does not, in fact, support the presumption. It is open to the Board to amend Schedule B, but in the absence of an amendment, the presumption is applicable to this case.
In this case the fact the worker smoked was insufficient evidence to rebut the presumption that his lung cancer was due to the nature of his employment. The introduction of other possible causes for the disease does not, by itself, prove that lung cancer was not due to the nature of employment. Lastly, the panel rejected the employer’s argument that the presumption was rebutted because the worker was diagnosed with lung cancer only six years after starting work at the aluminum smelter. Given that the presumption attaches when, at or immediately before the date of the disablement, the worker was employed in the relevant process or industry, it would be curious if the presumption could be defeated on the basis that the work in the relevant industry occurred too close to the diagnosis of the disease.
WCAT Decision Number: WCAT-2005-02493-RB
WCAT Decision Date: May 13, 2005
Panel: Randy Lane, Vice Chair
_____________________________________________________________________
Introduction
The worker, a 43-year-old employee of an aluminum smelter, died of lung cancer in February 1981. His widow, Ms. H (not her real initial) applied to the Workers’ Compensation Board (Board) in April 2002 for compensation benefits.
By decision of October 31, 2002 the Board advised Ms. H that her claim was statute barred under section 55 of the Workers Compensation Act (Act) and that it was more likely the worker’s lung cancer occurred as a result of his having smoked a package of cigarettes a day for 25 years.
Ms. H appealed the October 31, 2002 decision to the former Workers’ Compensation Review Board (Review Board). With the assistance of the union to which her husband belonged, Ms. H submitted notices of appeal - part 1 and part 2 and an August 3, 2004 submission. The worker’s employer was notified of the appeal, and it provided an August 11, 2004 submission. By letter of August 17, 2004 Ms. H’s representative advised that no response would be made.
By letter of July 13, 2004 Ms. H was advised that the appeal would proceed by way of written submissions. That decision does not bind me if I consider that an oral hearing is necessary. I consider a fair and thorough decision may be reached on this appeal without holding an oral hearing.
Issue(s)
At issue is whether Ms. H’s claim for dependant’s benefits is statute-barred and whether the worker’s death was due to the nature of his employment.
Jurisdiction
This appeal was filed with the Review Board. On March 3, 2003, the Review Board and the former Appeal Division of the Board were replaced by the Workers’ Compensation Appeal Tribunal (WCAT). As this appeal had not been considered by a Review Board panel before that date, it has been decided as a WCAT appeal. (See the Workers Compensation Amendment Act (No. 2), 2002, section 38.)
Background and Evidence
The worker was born in 1937. He moved to Canada with his wife in 1975. He commenced work with the employer on November 11, 1975 as a potman in the potroom. He worked as a potman until April 1979 when he became a cell operator and continued to work in the potroom. He suffered a back injury at work on December 1, 1980. The findings from a bronchoscopy of the left lung in early January 1981 establish that the worker was diagnosed with bronchogenic carcinoma. Material obtained from the Cancer Control Agency of British Columbia indicates that he was then diagnosed with adenocarcinoma of the upper left lobe. The worker died in late February 1981.
As part of its adjudication of Ms. H’s claim, the Board obtained information as to the number of benzene soluble material (BSM) years experienced by the worker. Records of the Cancer Control Agency of British Columbia established that the worker had a total of 4.55 BSM years.
Information on file indicates that the worker smoked a package of cigarettes a day since he was a “teenager.” It is not clear whether the worker started at age 13 or as late as age 19. He was smoking as of early 1981. Thus, he smoked between 24 and 30 years.
The Board also obtained an opinion from Dr. G, a specialist in internal medicine and the Board’s internal medicine consultant. Dr. G’s October 7, 2002 opinion includes the following comments:
Benzene soluble material exposures are associated with an increased risk for the development of bladder cancer. The Workers’ Compensation Board has developed a policy specific for aluminum workers, BSM exposure and compensable cancer risk. At a cumulative dose of 4.55 mg/m³ the worker has a relative risk less than 1.16 and would not qualify for support even if he did develop bladder cancer and not lung cancer.
Lung cancer risk in aluminum workers may be elevated as a result of exposure to polycyclic aromatic hydrocarbons from coal tar pitch (a benzene soluble material). There are several studies that show no association between lung cancer and aluminum workers (#1, 2, 6, 7 and 8) or a weak association (#3, 4 and 5) usually confounded by smoking or silica exposure in sandcasting aluminum.
In evaluating the worker’s exposure to carcinogenic substances it is clear that the most significant exposure increasing risk for lung cancer was his smoking history. His smoking history of a pack/day since mid-teens gives the worker a 25-30 packyear history. This exposure is significantly more important than any occupational exposures and is much more likely to have caused his fatal disease.
In summary, I believe the worker’s fatal metastatic lung carcinoma occurred as a result of a 25 pack/year smoking history and not any occupational exposures associated with his employment at [the employer].
[reproduced as written, save for change noted.
The numbers in Dr. G’s opinion refer to articles cited
by him which will be discussed later in this decision.]
In her October 31, 2002 decision the case manager commented that there was no indication on the claim file of any special circumstances which precluded the filing of a claim within the time limits prescribed by section 55 of the Act. She cited Dr. G’s opinion.
Reasons and Findings
Section 55 of the Act (Special Circumstances)
If an application is not filed within one year of the date of injury, death or disablement from an occupational disease, no benefits are payable unless there were special circumstances which precluded the filing of an application within one year. If the application is filed more than three years after the date of disablement by an occupational disease, subsection 55(3.1) is applicable.
As of April 2002, that subsection provided as follows:
The board may pay the compensation provided by this Part for the period commencing on the date the board received the application for compensation if
(a) the board is satisfied that special circumstances existed which precluded the filing of an application within one year after the date referred to in subsection (2), and
(b) the application is filed more than 3 years after the date referred to in subsection (2).
Thus, the issue is whether there were special circumstances in the one-year period following the worker’s death. It is not necessary to establish that there were special circumstances in all the years between 1981 and 2002.
Item #93.22 of the Rehabilitation Services and Claims Manual, Volume I (RSCM I) provides that section 55 requires that two requirements must be met before an application received outside the one-year period can be considered on its merits:
1. There must have existed special circumstances which precluded the application from being filed within that period, and
2. The Board must exercise its discretion to pay compensation. The application cannot be considered on its merits if no such special circumstances existed or the Board declines to exercise its discretion in favour of the claimant.
That item includes the following comments as to what is meant by special circumstances:
It is not possible to define in advance all the possible situations that might be recognized as special circumstances which precluded the filing of an application. The particular circumstances of each case must be considered and a judgment made. However, it should be made clear that in determining whether special circumstances existed, the concern is solely with the claimant's reasons for not submitting an application within the one-year period. No consideration is given to whether or not the claim is otherwise a valid one. If the claimant's reason for not submitting an application in time are not sufficient to amount to special circumstances, the application is barred from consideration on the merits, notwithstanding that the evidence clearly indicates that the claimant did suffer a genuine work injury.
WCAT Decision #2003-01335-RB issued on July 4, 2003 (viewable on the Internet at WCAT’s website at http://www.wcat.bc.ca) included the following comments concerning special circumstances:
Appeal Division decisions do not constitute policy, but serve to illustrate the interpretation and application of Board policy and the Act in particular cases. Three published Appeal Division decisions are summarised below, to assist in considering the worker's appeal regarding the existence of special circumstances.
In Decision #91-0153 (7 W.C.R. 93), the panel found that special circumstances had precluded the worker from filing an application for compensation because the worker was given advice by a claims adjudicator that effectively precluded him from applying for compensation.
In Decision #91-0851 (7 W.C.R. 211), the panel found that a rigid and narrow interpretation of the word "preclude" as "absolutely prevent" was not justified, and that a liberal interpretation of section 55(3) was appropriate. The panel found that neither the worker nor the employer was aware of the one year provision in section 55, and both acted on the assumption that neither a claim nor a report to the Board was necessary or reasonable unless they had proof establishing an industrial cause for the worker's disability. Had a report been made by the employer to the Board, an application form would have been provided to the worker, and he likely would have completed this. The panel found that it would be unfair if, given this set of circumstances, the only adverse consequences of the failure to report were now visited on the worker. The panel found that there were special circumstances which precluded the worker from applying for compensation within one year.
In Decision #92-0144/92-0145 (8 W.C.R. 85), the panel cited the following reasoning of the Federal Court of Appeal in Attorney General of Canada v. Albrecht, [1985] I.F.C. 710 (F.C.C.) interpreting the requirement in the Unemployment Insurance Act that a claimant show "good cause" for delay in making a claim.
[A]n obligation, with its concomitant duty of care, can be demanding only to a point at which the requirements for its fulfilment become unreasonable. In my view, when a claimant has failed to file his claim in a timely way and his ignorance of the law is ultimately the reason for his failure, he ought to be able to satisfy the requirement of having 'good cause' when he is able to show that he did what a reasonable person in his situation would have done to satisfy himself as to his rights and obligations under the Act. This means that each case must be judged on its own facts and to this extent no clear and easily applicable principle exists; a partially subjective appreciation of the circumstances is involved which excludes the possibility of any exclusively objective test. I think, however, that this is what Parliament had in mind and in my opinion this is what justice requires.
The policy in item #93.22 of the RSCM indicates that it is difficult to prescribe rules or criteria for the establishment of "special circumstances". In conjunction with the considerations based on the Albrecht case, a number of factors are frequently cited as constituting special circumstances. These factors assist in analysing a particular circumstance with regard to what a reasonable person in the worker's situation would have done. These include:
* characteristics of the worker such as language difficulties, limited education, recent immigration or other factors which would create obstacles to understanding that there is a system of workers' compensation and how to access it;
* lack of knowledge that an injury or disease might be work related because of delayed onset of the condition, minor nature of the original injury, or failure to recognise that it is related to work;
* reliance on the advice of others such as a physician or employer where the worker is dependent on such advice due to language difficulties, limited education, or other similar difficulty.
While that decision is phrased with respect to a worker, it is applicable to claims by dependants, such as that of Ms. H.
Ms. H’s representative indicates that Ms. H did not file an application when her husband died of cancer because “I didn’t know.” She immigrated to Canada in 1975 from Portugal. Her English language skills were very limited. At the time the worker died in 1981, her English language skills were still very poor. She had little or no support group within the community. She was left with three children to raise. Ms. H met with the employer’s benefits administrator, and no mention was made that she should consider filing a claim with the Board. The worker’s physician never advised the worker or Ms. H that the worker’s lung cancer may have been caused by his work environment. The Board terminated the worker’s benefits under his 1980 back claim, on the basis that his back pain was caused by his cancer. The Board never apprised the worker or Ms. H that his cancer could be related to exposure at his workplace, and it did not initiate an investigation. (My review of the worker’s 1980 claim confirms that benefits were terminated on the basis of the worker’s cancer, that no investigation by the Board was undertaken, and that no advice was given by the Board regarding the cause of the worker’s cancer.)
After the worker’s death, Ms. H’s contact with the employer “…basically ended at this time so she would not be privy to any [employer] or Union correspondence or literature after this time.” Ms. H contacted the union in response to an article it had placed in a local newspaper in April 2002 concerning union members who had died due to occupational diseases.
The worker’s employer agrees that special circumstances precluded Ms. H from filing an application within the applicable time frame.
I find that there were special circumstances which precluded Ms. H from making an application for compensation within the time period set out in section 55 of the Act. I consider that her English language skills were such that she would have relied on others, rather than have undertaken research by herself, as to benefits available from the Board. She was in contact with the Board, the employer, and her husband’s doctor, and no mention was made of applying to the Board. There is no suggestion that she was dissuaded from applying or that she asked the employer or the worker’s doctor if she should apply. Her obligation to apply for compensation was independent of any obligation on the employer or the worker’s doctor to have notified the Board. However, it would not have been unreasonable for her to have failed to have applied for compensation, given that neither the employer nor the worker’s doctor suggested that she apply for compensation.
As discussed in Appeal Division decisions such as Appeal Division Decisions #2002 1180 and #2001-0732, Board policy involves consideration of discretion to pay compensation. That discretion “…is a different issue from whether the worker is entitled to compensation, in respect of the adjudication of the claim as to whether it is acceptable on the merits.”
I find that the Board should exercise its discretion in favour of Ms. H. This is not a case where the passage of time has significantly affected the Board’s ability to adjudicate Ms. H’s claim. It has information as to the worker’s smoking history, his occupational exposure, and his cause of death.
Subsection 6(3) and Schedule B of the Act (Prolonged Exposure)
Since 19801 Schedule B of the Act has contained item 4(e), as follows:
Description of Disease
Description of Process or Industry
Primary cancer of the lung
Where there is prolonged exposure to
(1)
aerosols and gases containing arsenic, chromium, nickel or their compounds; or
(2)
bis (chloromethyl) ether; or
(3)
the dust of uranium, or radon gas and its decay products; or
(4)
particulate polycyclic aromatic hydrocarbons.
The effect of subsection 6(3) of the Act is that if a worker at or immediately before the date of the disablement was employed in a process or industry mentioned in the second column of the schedule, and the disease contracted is the disease in the first column of the schedule set opposite to the description of the process, the disease is deemed to have been due to the nature of that employment, unless the contrary is proved.
Item 4(e) in Schedule B is of interest, given that three unpublished Appeal Division decisions (Appeal Division Decisions #98-1063, #98-1085, #98-1122) supplied by Ms. H’s representative review the application of that policy item to the claims of three widows whose husbands worked at the worker’s place of employment and who died of lung cancer. The Appeal Division panel which decided each of the three cases noted that exposure at the workplace would have involved benzene soluble material which would, in turn, have included polycyclic aromatic hydrocarbons (PAHs), a known cause of lung cancer. A succinct statement as to the matter is found in Appeal Division Decision #98 1122:
Coal tar pitch is used in the vertical stud Soderberg process for the production of aluminum. The nature of the process releases coal tar pitch volatiles (C.T.P.V.) into the air. One component of C.T.P.V. is the material that is soluble in the solvent benzene. This fraction of C.T.P.V. is referred to as the benzene soluble material (BSM). BSM is measured in milligrams per cubic meter of air (mg/m3). The BSM itself contains at least 30 different polycyclic aromatic hydrocarbons (PAHs) as well as several amines and other compounds. One of the PAHs in the BSM is benzo-a-pyrene (Bap). Bap is measured in micrograms per cubic meter of air ( g/m3). In Appeal Division Decision #96-0727 there was some discussion as to the likely amount of Bap in the BSM at [the employer]. It was determined that there was likely about 1% Bap in the BSM. This has significance in converting Bap measurements to total BSM and vice-versa. To convert Bap in g/m3 to total BSM in milligrams per cubic meters (where Bap is 1% of total BSM) the Bap figure must be divided by 10. For example, the controversial measurement of 20.47 g/m3 Bap (referred erroneously in the submissions as 20.47 g/m3 BSM) is the equivalent of about 2 mg/m3 BSM.
[reproduced as written, save for change noted]
The case manager’s decision does not document any consideration of subsection 6(3) of the Act or Schedule B.
I accept Dr. G’s comment that the worker died of metastatic lung cancer. I find that the worker died of primary cancer of the lung and that the requirements in the first column of Schedule B have been met.
I have considered whether the requirement found in the second column of Schedule B has been met. Can it be said that, at or immediately before the date of the disablement, the worker was employed in a process or industry which involved “prolonged exposure” to PAHs?
A key concern in connection with the presumption is the fact that the presumption attaches to “prolonged exposure.” Before considering the word “prolonged”, I consider that the word “exposure” deserves consideration. I consider that the word “exposure” in item 4(e) of Schedule B must refer to encountering PAHs at a level in excess of that day-to-day level we may encounter. If the word “exposure” does not include some requirement involving the amount of PAHs encountered, then the presumption becomes meaningless.
Item #26.21 of RSCM I2 contains the following discussion relevant to the word “prolonged”:
Difficulties may arise in determining whether the worker was employed in the process or industry described in the second column. This often arises because of the use of such words as “excessive” or “prolonged”. While the Board would like to define more precisely the amount and duration of exposure required instead of using these words, it is usually not possible. The exact amounts will often vary according to the particular circumstances of the work place and the worker, or may not be quantified with sufficient precision by the available research. However, while such words are of uncertain meaning, there is valid reason for inserting them. Individual judgment must be exercised in each case to determine their meaning, having regard to the medical and other evidence available as to what is a reasonable amount or duration of exposure.
[emphasis added]
That policy establishes that “prolonged” refers to duration of exposure and “excessive” refers to amount of exposure. The Concise Oxford Dictionary (11th edition) defines the word “prolonged” as “lengthy.” As noted in Appeal Division Decision #2002 11303, a decision which concerned the item in Schedule B dealing with prolonged exposure to benzene, “There is no requirement in this item [item 4(f)] with respect to any minimum level of exposure, in terms of finding that the Schedule B presumption applies.” Further, the panel in Appeal Division Decision #2003-0584, also a benzene case, commented as follows:
Generally, the term "prolonged" refers to the duration of exposure and connotes exposure over an extended period of time. I interpret the term "prolonged" as relating specifically to the duration of exposure. There is no requirement in Item 4(f) with respect to any minimum level of exposure, in terms of finding that the Schedule B presumption applies.
I accept the above comments concerning the level of exposure, subject to the requirement that a worker has encountered a level of PAHs that is not the same as that which we all encounter in our day-to-day lives. Keeping that proviso in mind, I find that the discussion in item #26.21 of the RSCM I concerning “amounts” is not applicable to the issue of duration. The last sentence of the above excerpt from item #26.21 is applicable to duration, and I interpret it to mean that, in each case, prolonged exposure must be determined with “regard to the medical and other evidence available as to what is a reasonable amount or duration of exposure.” I interpret the policy to mean that once a worker has exceeded a reasonable duration, the worker has experienced prolonged exposure.
Yet, what is a reasonable duration of exposure, and how does one define it in the case before me? Does it occur when a worker has encountered PAHs at a level associated with a doubling of cancer risk in the literature?4
In Appeal Division Decision #2001-1535 the panel considered the term “prolonged” in connection with “prolonged contact” and skin cancer noted at item 4(g) of Schedule B. The panel noted an earlier Appeal Division decision, which it indicated was reported at 9 W.C.R. 177, in which the earlier panel considered item 4(g).5 The panel in Appeal Division Decision #2001-1535 noted that the earlier Appeal Division panel found that intermittent exposure over a period of years would qualify as “prolonged”, and it further commented as follows:
I agree with the reasoning of the panel with regard to the interpretation of the word “prolonged”. Prolonged clearly means something more than occasional. Intense intermittent brief periods of exposure over a long period of time can be taken to be “prolonged”. It is not necessary to say that the contact was all day long for a period of time to say that it was prolonged contact.
I find that, in the context of exposure to PAHs, prolonged exposure does not mean continuous exposure. Yet, at the same time, there must be more than sporadic exposure. I consider that the requirement that there be prolonged exposure involves a requirement as to the frequent and ongoing nature of exposure. I am aware that the word frequent does not occur in item 4(e); it does occur in other items in Schedule B. However, I find that the expression “prolonged exposure” involves a frequency component.
If the assessment of whether a disease has satisfied the terms of Schedule B is determined by whether the worker’s exposure exceeds the exposure declared in the medical and scientific literature to be associated with a doubling of the risk of developing the occupational disease, Schedule B would not serve the purpose for which it was designed. Under such an assessment, adjudication associated with subsection 6(3) would be little different from adjudication under subsection 6(1). I say that because an important consideration associated with adjudication of many diseases under subsection 6(1) is whether the exposure of a worker is similar to, or exceeds, that of workers whose exposure is associated with a doubling of the risk of developing the disease of interest. The only important difference between adjudication under the two subsections would be that under subsection 6(3) the disease would be presumed to be due to the worker’s employment, once the decision-maker was satisfied that a worker’s exposure was associated with a doubling of risk of developing the disease. I consider that the effect of Schedule B and subsection 6(3) involves more than that.
The following passage from item #26.21 of RSCM I6 establishes that the purpose of Schedule B is to relieve decision-makers from reviewing the medical and scientific literature:
The fundamental purpose of Schedule B is to avoid the repeated effort of producing and analyzing medical and other evidence of work-relatedness for a disease where research has caused the Board to conclude that such disease is specific to a particular process, agent or condition of employment (see #26.01). Once included in Schedule B, it is presumed in individual cases that fit the disease and process/industry description that the cause was work related. A claim covered by Schedule B can be accepted even though no specific evidence of work relationship is produced. A review of the available medical and scientific evidence would establish a likely relationship between the disease and the employment. The listing in the Schedule avoids the effort of producing the evidence in every case. Where the research does not clearly relate the disease to particular employments, the disease is not listed in Schedule B and the issue of work-relatedness must be determined on a case-by-case basis (see #26.22).
[emphasis added]
Determining whether a worker’s specific exposure matched or exceeded exposure noted in the literature associated with a doubling of risk would mean that, in each case, an assessment of the literature would need to be done to determine whether the figures in the literature had changed. That appears to be the approach taken in Review Reference #7897 issued by the Board’s Review Division in May 2004 (that decision may be viewed on the Internet at the Board’s website). That approach would seem to be contrary to the passage from item #26.21 reproduced immediately above. Such a determination would be very contingent on the adequacy of the literature search in connection with each disease claim. This is, to some extent, true in each case where a claim for a disease like cancer is adjudicated under subsection 6(1) of the Act. Was it intended that adjudication under subsection 6(3) be similar? The language in the first excerpt from item #26.21 reproduced earlier in this decision suggests that recourse to the literature can be undertaken to reach conclusions as to what is a reasonable duration of exposure in determining whether there has been prolonged exposure.
I attach considerable weight to the listing of a disease in Schedule B, coupled with the language found in the second passage from item #26.21 reproduced above. I accept that the initial passage from item #26.21 reproduced earlier in the decision provides relevant comments concerning qualifying words such as “prolonged” or “excessive” in Schedule B; it must be kept in mind that the listing in item 4(e) is not merely “exposure.”
I find that the worker’s five years of exposure to PAHs amounted to prolonged exposure to PAHs. The presumption is applicable to Ms. H’s claim for compensation. The Board erred in failing to consider the presumption.
Subsection 6(3) and Schedule B - Presumption Rebutted?
Item #26.21 of RSCM I includes the following passages7 with respect to the type of evidence that is capable of rebutting the presumption:
Inclusion of the words “unless the contrary is proved” in Section 6(3) means that the presumption is rebuttable. Even though the decision maker need not consider whether working in the described process or industry is likely to have played a causative role in giving rise to the disease, they must still consider whether there is evidence which rebuts or refutes the presumption of work-relatedness.
The standard of proof to be applied in determining whether the presumption has been rebutted is proof on a balance of probabilities. This is the same basic standard of proof applicable in the workers’ compensation system. If the evidence is more heavily weighted in favour of a conclusion that it was something other than the employment that caused the disease, then the contrary will be considered to have been proved and the presumption is rebutted. The gathering and weighing of evidence generally is covered in #97.00 through #97.60.
[emphasis added]
Once it is established that a worker’s exposure was prolonged, is it is open to a decision-maker to say that the presumption is rebutted on the basis that the exposure was not sufficient in amount? The decision of the British Columbia Court of Appeal in Re Evans and Workers' Compensation Board (1982) 138 DLR (3d) 346 dealt with the Schedule B item concerning “a process or operation where there is exposure to silica dust, ‘hard metal’ grinding, tungsten carbide grinding.” The court commented as follows:
In the first step that is directed to be taken by s. 6(3) it is improper to consider whether the exposure was sufficient to cause disease. What matters at that stage is whether there was any exposure. The extent of the exposure is a matter to be weighed only after the tests in s. 6(3) have been applied. Then it is to be weighed with the strong presumption that “the disease shall be deemed to have been due to the nature of that employment unless the contrary is proved”.
[emphasis added]
I am aware that the panel in Appeal Division Decision #2001-1061 quoted that passage from the Evans decision in the context of a case concerning benzene and leukemia. Of interest is the fact that the Evans decision preceded the promulgation of the RSCM in May 1984 (and the RSCM I and RSCM II in 2002). The Evans decision preceded item #26.21 and its predecessor item #25.21. It is true that portions of item #26.21 are derived from Workers’ Compensation Reporter Series Decision No. 326, issued on June 18, 1980, approximately two years before the Evans decision. However, the critical passage in item #26.21 concerning the standard of proof needed to rebut the presumption was added to policy in January 1995 when chapter 4 of the RSCM underwent significant revisions. My point in reciting this history is to illustrate that the Board’s policy on this critical point was created after the Evans decision.
I find that the Board has identified in policy what is required to rebut the presumption. The evidence must establish that it was something other than employment; that requirement is not satisfied by determining that the exposure was insufficient and therefore something else must have been the cause. There must be positive proof of another cause of the disease rather than some question as to the adequacy of proof that employment is the cause of the disease. Had the Board wanted to avoid that requirement, the policy could have stated as follows:
If the evidence is more heavily weighted in favour of a conclusion that employment was not the cause of the disease, then the contrary will be considered to have been proved and the presumption is rebutted.
That formulation of policy would have made it clear that the adequacy of the evidence supporting employment as the causative agent was the concern when determining whether the presumption was rebutted.
I note that in Appeal Division Decision #2003-0584 the panel made the following observations concerning the rebuttal of the presumption, after noting comments in the Evans case:
This does not mean that the amount of the exposure is irrelevant to the consideration of the claim. The amount of exposure to benzene may be relevant in rebutting the presumption if the presumption is found to apply. For example, if the worker is found to have significant non-work related exposure to a substance that may cause leukemia and the prolonged exposure to benzene at work is considered so negligible that it is unlikely to be the cause of the leukemia in that particular case, then the presumption may be rebutted. That however is a matter to be determined in the second stage of the Schedule B analysis after the presumption is found to apply.
The panel appeared to commence its analysis by saying that the amount of exposure may be considered when determining if the presumption is rebutted. I question whether that is an option, given policy. However, the panel tied the exercise to an examination of whether the worker had non-work-related exposure to a substance that may cause leukemia, and that accords with the standard of proof language found in item #26.21.
Dr. G’s opinion referred to a number of journal articles issued by the following authors (listed in order of date of publication): Rockette and Arena8, Abramson et al.9, Spinelli et al.10, Armstrong et al. (1994)11, Rønneberg and Andersen (1995)12, Seldén et al.13, Moulin et al. (2000)14, and Romundstad et al. (2000a).15 I obtained copies of those articles, as well as copies of articles by the following authors (listed in order of date of publication): Milham16, Andersen et al.17, Gibbs (1985)18, Mur et al.19, Moulin et al.20, Rönneberg and Langmark21, Mastrangelo et al.22, Boffetta et al.23, Gibbs (1998)24, Rønneberg et al. (1999)25, Romunstad et al. (2000b)26, Romundstad et al. (2000c)27, and Armstrong et al. (2004)28. (The last article was published in June 2004, a few months before the commencement of submissions to WCAT.)
I appreciate that the information in the studies may not necessarily point to a strong relationship between employment in the aluminum smelting industry (which involves exposure to PAHs) and lung cancer. In that regard, Dr. G pointed out that several studies showed no association (Romundstad et al. (2000a), Moulin et al. (2000), Spinelli et al., Abramson et al., and Rockette and Arena) or only a weak association (Seldén et al., Rønneberg and Andersen, and Armstrong et al. 1994). He referred to the article by Rønneberg and Andersen; however, that article (like that issued by Milham) concerned pre-baked carbon anodes, whereas the process in use at the worker’s workplace involved the vertical Soderberg process. Mur et al. noted that an excess risk of lung cancer found in aluminum workers could be attributed mainly to use of the Soderberg process. Further, the article by Seldén et al. did not concern the primary production of aluminum; it concerned aluminum foundries and secondary aluminum smelters.
Gibbs’s 1985 article concerned the employer’s Quebec facility. Gibbs noted that mortality from lung neoplasms was consistently above the expected figure and higher than that among men never exposed to tars. Mortality increased steadily with tar-years of exposure. The excess was not really evident until men had achieved 21 or more years of tar exposure or 21 or more years since first exposure. The article by Spinelli et al. concerned the workplace at which the worker actually worked. The authors noted that the SIR for lung cancer was 0.97 and the SMR for cancer mortality was 0.93. There was a weak association with CTPV exposure that was not statistically significant.29 The authors commented that the association noted by them did not duplicate the “strong association” seen in the study by Gibbs. They commented that one possible explanation was that their study did not have the power to detect a true association. They commented that previous studies had suggested “a much longer latent period.”
Armstrong et al.’s 1994 article regarding lung cancer included many of the deaths noted in Gibbs’s 1985 article, as well as the deaths of men studied in follow up by Gibbs and the deaths in men not studied by Gibbs. They determined that there was a clear excess of lung cancer risk in men who had worked in the Soderberg potrooms and in jobs generally having high exposures to CTPVs, and that the risk was not due to confounding by smoking. They commented that identification of the specific component of CTPVs that caused the cancer was not possible, and they observed that lung cancer excesses had been observed in other groups exposed to “polynuclear aromatic hydrocarbons”, suggesting that this component of CTPVs may be the cause of cancer. The unadjusted rate ratios for workers working with Soderberg pots from one to 19 years and from 10 to 19 years was 1.33. Those figures were not statistically significant. Adjusting for smoking did not increase the rate ratios significantly. The unadjusted rate ratio for 20 to 41 years of work was 1.91, and it was statistically significant. Work in the “potlining department” from one to nine years was associated with a statistically significant unadjusted rate ratio of 2.34, which increased to a statistically significant figure of 2.48 when adjusted for smoking. The adjusted rate ratio dropped to a non-statistically significant figure of 1.89, when adjusted for smoking and Soderberg exposure. The authors advised that extrapolation of the results to other Soderberg plants was cautioned, as other studies had shown weaker evidence for associations or virtually no evidence.
In Rønneberg et al. (1999) the authors documented the absence of an association between exposure to PAHs and lung cancer. They thought a plausible explanation for the negative results could be lower exposure levels and a shorter follow-up than in the studies by Gibbs (1985) and Armstrong et al. (1994). Moulin et al. (2000) detected no lung cancer risk even in workshops where PAH exposure was likely to have occurred, and no trend was observed according to duration of exposure and time since first exposure. Romundstad et al. (2000b) noted that the absence of a lung cancer risk did not accord with the 1994 study by Armstrong et al. They commented that the risk of lung cancer among of production workers had not been consistent among epidemiological studies. Romundstad et al. (2000c) found no association between exposure to PAHs and lung cancer; they reiterated comments found in Romundstad et al. (2000b). They observed that the high exposure to PAHs experienced by workers in the Soderberg departments did not seem to result in an increased risk of lung cancer in their studies. Romundstad et al. (2000a) studied six aluminum plants and determined that the results gave no support to an association between PAH exposure and lung cancer in the primary aluminum industry. The plants included horizontal Soderberg processes and pre-baked processes. Their study was among the largest studies of aluminum production workers with almost 50 years of follow-up.
The recent review by Armstrong et al. asserts that occupational exposure to PAHs by inhalation is associated with a risk of lung cancer. They base their assertion on the studies concerning various industries. Concerning the aluminum industry, they reviewed Armstrong et al. (1994), Milham, Mur et al., Moulin et al. (2000), Rockette and Arena, Romundstad et al. (2000a), and Spinelli et al.
However, to what extent can the evidence in the literature be used to rebut the presumption that there is a causal link between primary cancer of the lung and prolonged exposure to PAHs? I do not consider that the literature can be used in that fashion. To do so would be to rebut the very presumption in Schedule B, rather than the presumption in the specific worker’s case.
I have considered whether Dr. G’s opinion is sufficient to rebut the presumption that the worker’s lung cancer was due to the nature of his employment.
Dr. G was not asked whether the presumption was rebutted. In that regard, his opinion is affected by the same problem that affected the opinion of Dr. A considered by the panel in Appeal Division Decision #98-1085:
Dr. [A] responded to a series of questions posed to him by the Review Board. However, with respect, the Review Board, for the most part, asked the wrong questions. As the Review Board had already concluded that the worker was entitled to the presumption that his lung cancer was due to the nature of his employment the question should have been, "What is the evidence that proves the worker's lung cancer was not due to the nature of his employment?" Rather, the questions answered by Dr. [A] appear to relate to the general question of causation. A determination as to whether the "contrary is proved" involves more than an adjudication with respect to causation under section 6(1) and then applying the result to section 6(3). That is, it is improper to merely decide, on a balance of probabilities, whether the worker's lung cancer was due to the nature of his employment and then to use that result to decide whether the contrary is proved under section 6(3). That approach essentially renders the presumption ineffective.
I consider that those comments are applicable to Dr. G’s opinion in the case before me. In particular, his comments as to the link between lung cancer and exposure to PAHs appear to challenge the presumption in Schedule B. I do not consider that it is open to the Board to rebut the presumption by asserting that the evidence in the literature does not, in fact, support the presumption. It is open to the Board to amend Schedule B so as to attach further conditions to the process or industry. By that, I mean that the Board could amend Schedule B so that it reads as follows: “prolonged exposure to…particulate polycyclic aromatic hydrocarbons, save for exposure in the aluminum smelting industry to which the presumption does not apply.” Such an amendment cannot be undertaken by a Board manager. In the absence of such an amendment to Schedule B, I consider that the presumption is applicable to the case before me.
Dr. G’s reference to the Board’s policy concerning bladder cancer, at item #30.10 of RSCM I, does not assist in the adjudication of this lung cancer claim. He does not assert that bladder cancer and lung cancer share the same risks.
Dr. G’s comments as to the worker’s smoking history are of note. Yet, as commented in Appeal Division Decision #98-1085, “The introduction of other possible causes does not by itself prove that [the worker’s] lung cancer was not due to the nature of his employment at [the workplace].” It should be kept in mind that “The presumption in section 6(3) that the worker’s lung cancer was due to the nature of his employment does not mean that the work place exposures to PAHs are necessarily the sole cause of the worker’s lung cancer.” As observed by the panel in Appeal Division Decision #98 1085, “…there may very well be multiple causes, even on a statistical basis, of [the worker’s] lung cancer.” The worker who was the subject of the decision in Appeal Division Decision #98-1085 had between 0.8 and 3.2 BSM years of exposure between 1977 and 1985 and had a smoking history of 51 pack years of smoking according to the employer.
Can the worker’s employment between 1975 and 1980 be disregarded on the basis that the latency period for lung cancer means that employment in that period could not be relevant to the worker’s lung cancer diagnosed in 1981? Schedule B and subsection 6(3) do not appear to take into account latency periods in connection with diseases like cancer and leukemia. The presumption attaches when, at or immediately before the date of the disablement, the worker was employed in a process or industry mentioned in the second column. It would be curious if the presumption could be defeated on the basis that the work in the relevant industry occurred too close to the diagnosis of the disease.
The employer submits that the latency period for lung carcinoma is usually quite long. It notes that the worker’s smoking history was 25 to 30 pack years. If further submits that “According to science, it would appear unlikely that the condition was caused by employment exposure.” The employer does not provide any persuasive argument supporting a conclusion that 4.55 BSM years between November 1975 and December 1980 were incapable of producing the worker’s lung cancer and that some other exposure was the cause of the worker’s lung cancer.
After reviewing the matter, I find that the presumption has not been rebutted. I find that Dr. G’s opinion does not establish “…that it was something other than the employment that caused the disease….”
Conclusion
Ms. H’s appeal is allowed. I vary the case manager’s decision, as I find that there were special circumstances which precluded her from applying for compensation within one year after the worker’s death and that the worker’s death was due to the nature of his employment.
Reimbursement of expenses has not been requested, and it does not appear that any were incurred. I make no order for reimbursement.
Randy Lane
Vice Chair
RL/jy
1 Workers’ Compensation Reporter Decision No. 326, entitled “Re: Industrial Diseases” (5 W.C.R. 78), set out revisions to Schedule B. A portion of that decision was issued as BC Regulation 292/80.
2 This passage and all the other passages from item #26.21 noted in this decision have been part of Board policy for many years. This particular passage dates back to June 1980 when it appeared in item #19.21 of the Claims Adjudication Manual (the predecessor of the RSCM). When the RSCM came into existence in May 1984, item #25.21 discussed the presumption. It became item #26.21 in January 1995. Item #26.21 was amended in 2004 via Resolution 2004/05/18-02 of the Board’s board of directors. The amendment involved a deletion from the policy of comments dealing with workers who had been diagnosed with a disease many years after leaving the relevant process or industry. The policy formerly stated that those workers could be said to have been employed in that industry or process at or immediately before the date of disablement owing to the long latency period associated with the cancer. I note this last revision, as RSCM item #26.21 includes an effective date of June 2004 and provides that item #26.21 applies to all decisions, including appellate decisions, made on or after June 1, 2004. The more recent revision post-dates the case manager’s October 10, 2002 decision, but it is not relevant to the case before me.
3 This decision may be viewed on the Internet at the Board’s website at www.worksafebc.com, along with all other Appeal Division decisions issued in 2000 and thereafter mentioned in this decision.
4 Relative risk (RR) is the ratio of the disease incidence or death among people exposed to an agent to the disease incidence or death among the unexposed. A relative risk of 2.0 is often equated with a 50% likelihood that an exposed person’s disease was caused by the agent, and a relative risk greater than 2.0 would permit an inference that an individual's disease was more likely than not caused by the implicated agent. SMR is defined as a "standardized mortality ratio, equivalent to relative risk (observed cases divided by expected cases)." In cancer incidence studies SMR refers to standardized morbidity ratio; some authors also refer to SIR or standardized incidence ratio. An SMR may be expressed in two ways: for example, 150 or 1.5.
5 Given the nature of the issue being addressed, the earlier decision was Appeal Division Decision #93-0157, reported at 9 W.C.R. 219; Appeal Division Decision #93-0162, the case reported at 9 W.C.R. 177, concerned multiple myeloma and it did not involve item 4(g).
6 This passage was added to policy effective January 1995 when item #25.21 became item #26.21.
7 These passages were also added to policy effective January 1995.
8 Rockette, H.E. and Arena, V.C. The Mortality Studies of Aluminum Reduction Plant Workers: the Potroom and Carbon Department. Journal of Occupational Medicine. 1983 25:7: 549-57.
9 Abramson, MJ et al. Does aluminum smelting cause lung disease? American Review of Respiratory Disease. 1989; 139(4):1042-57.
10 Spinelli J.J. et al. Mortality and cancer incidence in aluminum reduction plant workers. Journal of Occupational Medicine. 1991; 33(11):1150-55.
11 Armstrong, B et al. Lung cancer mortality and polynuclear aromatic hydrocarbons: a case-cohort study of aluminum production workers in Arvida, Quebec, Canada. American Journal of Epidemiology. 1994 139(3):250-62.
12 Rønneberg, A and Andersen, A. Mortality and cancer morbidity in workers from an aluminum smelter with pre baked carbon anodes Part II: Cancer morbidity. Occupational and Environmental Medicine. 1995 52(4):250-254.
13 Seldén, AI et al. Cancer morbidity in workers at aluminum foundries and secondary aluminum smelters. American Journal of Industrial Medicine. 1997 32(5):467-77.
14 Moulin, JJ et al. A mortality study among workers in a French aluminium reduction plant. International Archives Occupational and Environmental Health. 2000 73(5):323-30.
15 Romundstad, P. et al. Cancer incidence among workers in six Norwegian aluminum plants. Scandinavian Journal of Work Environment and Health. 2000. 26:461-469.
16 Milham, S. Mortality in aluminum reduction plant workers. Journal of Occupational Medicine. 1979 Jul;21(7): 475 80
17 Andersen, A. et al. Risk of Cancer in the Norwegian Aluminum Industry. International Journal of Cancer. 1982 29:295-298.
18 Gibbs, G. Mortality of Aluminum Reduction Plant Workers, 1950 Through 1977. Journal of Occupational Medicine. 1985 27:(10):761-770.
19 Mur, J.M. et al. Mortality of Aluminum Reduction Plant Workers in France. International Journal of Epidemiology. 1987 16:257-264.
20 Moulin, JJ et al. Risk of lung, larynx, pharynx and buccal cavity cancers among carbon electrode manufacturing workers. Scandinavian Journal of Work Environment and Health. 1989 Feb;15(1):30-7.
21 Rönneberg, A and Langmark, F. Epidemiologic evidence of cancer in aluminum reduction plant workers. American Journal of Industrial Medicine. 1992;22(4):573-90.
22 Mastrangelo, G et al. Polycyclic aromatic hydrocarbons and cancer in man. Environmental Health Perspectives. 1996 Nov;104(11):1166-70.
23 Boffetta, P et al. Cancer risk from occupational and environmental exposure to polycyclic aromatic hydrocarbons. Cancer Causes and Control. 1997 May;8(3):444-72.
24 “Occupational Cancer Overview: Aluminum Reduction,” Health in the Aluminum Industry: Managing Health Issues in the Aluminum Industry ed. N.D. Priest and T.V. O’Donnell ( Middlesex University Press, 1998), pp. 135 -153.
25 Rønneberg, A. et al. Occupational exposure and cancer incidence among workers from an aluminum smelter in western Norway. Scandinavian Journal of Work Environment and Health. 1999 25(3):207-14.
26 Romundstad, P. et al. Lung and bladder cancer among workers in a Norwegian aluminum reduction plant. Occupational and Environmental Medicine. 2000 57(7):495-9.
27 Romundstad, P. et al. Cancer incidence and cause specific mortality among workers in two Norwegian aluminum reduction plants. American Journal of Industrial Medicine. 2000 37:175-183.
28 Armstrong, B et al. Lung cancer risk after exposure to polycyclic aromatic hydrocarbons: a review and meta-analysis. Environmental Health Perspectives. 2004 Jun;112(9):970-8.
29 A confidence interval is a range of values calculated from the results of a study within which the true value is likely to fall. The width of the interval reflects random error. If the limits of the interval do not include 100 (a relative risk of 1.0), the risk is statistically significant. The larger the sample size in a study (all other things being equal), the narrower the confidence boundaries will be (indicating greater statistical stability), thereby reflecting the decreased likelihood that an association found in the study would occur if the true association is 1.0. Confidence intervals are often noted in connection with relative risks. A 95% confidence interval means that the range set by the interval will contain the true risk 95% of the time.
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WCAT
Decision Number: WCAT-2005-02493-RB
1
Workers’ Compensation Appeal Tribunal 150, 4600 Jacombs Road, Richmond, B.C. V6V 3B1
Telephone: (604) 664-7800; 1-800-663-2782; Fax (604) 664-7898
WCAT
Workers’ Compensation
Appeal Tribunal
150 – 4600 Jacombs Road
Richmond, BC V6V 3B1
Telephone: (604) 664-7800
Toll Free: 1-800-663-2782
Fax: (604) 664-7898