WORKPLACE SAFETY AND INSURANCE BOARD
APPEALS RESOLUTION OFFICER DECISION
DECISION NUMBER: 20110032
OBJECTION BY: Worker’s Estate
PARTICIPANTS: Union representative, Employer
HEARING DATE: October 19, 2010
ISSUE
On behalf of the worker’s estate the worker representative objects to the February 10, 1997; March 25, 2005; and October 8, 2009 adjudicator decisions denying entitlement for lung cancer.
HOW THE ISSUE ARISES
The worker was employed as a mill operator and in the crushing plant from 1951to 1986. The worker passed away owing to the effects of primary metastatic lung cancer February 5, 1996 at age 65.
The claim was initially reviewed with the conclusion there was no significant exposure to arsenic and soluble nickel. Noting the worker’s smoking history it was concluded there was a higher probability the cancer was a result of smoking rather than workplace exposures.
The union subsequently argued the worker was employed in the sinter plant and entitlement under the relevant policy was in order. As the employer records did not confirm this employment history the denial of entitlement was confirmed.
AUTHORITY
11-01-03 - Merits and Justice (Decisions related to occupational disease)
16-02-02 – Lung Cancer in the Nickel Producing Industry
16-02-05 – Asbestosis
ASSESSMENT OF THE EVIDENCE
I have reviewed the record and considered the evidence and submissions.
Submissions
The worker representative notes there are two arguments. The first is that the worker was employed in the sinter plant in the 1950’s and the claim is allowable based on this exposure. The second is that in the absence of accepting sinter plant exposure the worker had substantial asbestos exposure and his condition is allowable based on this exposure.
The employer suggests the employment records do not confirm sinter plant employment and there is no evidence of asbestos exposure or effects. The employer suggests an analysis of relative risk suggests the probability the worker’s condition was a result of his smoking history.
Analysis
The case hinges on a number of issues. The first is the necessary finding of fact in relation to the worker’s sinter plant exposure. The second relates to asbestos exposure while employed in the milling operations. Finally, there is the appropriate interpretation of the medical reporting in respect of the relevant policy and entitlement criteria.
1) Sinter Plant Employment
The parties have confirmed the worker was employed from 1951 to 1986 primarily in the employer’s milling operations.
The worker representative notes the worker’s family maintains he worked in the sinter plant and the worker representative has presented an affidavit to this effect. The representative notes while this affidavit represents a somewhat non-traditional form of evidence he suggests it should carry significant weight. The representative further suggests it was common practice to move workers to the sinter plant but does recognize the union was unable to identify co-workers who could confirm this worker’s employment history. Finally, the worker representative suggests the time cards for workers who were loaned to the sinter plant would not record this transfer. The worker representative notes it is the union position there was a separate record known as the Time Book Registry kept in the sinter plant in which the time for workers on loan was recorded. The representative notes it is the union position this document was inappropriately destroyed by the employer.
The employer notes it is the employer position the Time Sheets supplied for the worker are in fact the Time Book Records which are identical to the time sheets. The employer position is that these documents provide an accurate employment history. The employer notes these cards identify all jobs, days, and hours worked. The employer notes they also provided copies of time cards for a different worker demonstrating how time worked in the sinter plant was identified. The employer notes there is no indication on the worker’s time sheets that he ever worked in the sinter plant and he was never identified on any surveillance program. The employer notes the worker was employed in the milling operations and suggests workers from this area would not typically transfer to the sinter plant. Finally, the employer notes the affidavit provided was not confirmed and is contrary to the other evidence on file.
Before addressing the specifics of the worker’s case I consider it appropriate to first review the evidence as to the general employment circumstances in the early 1950’s. As I understand the general employment details the parties agree workers would be transferred to the sinter plant as required. The union position is that the documents recording the specific work hours were kept in the sinter plant and later destroyed (Time Book Registry). The employer position is that the time sheets still in existence record those circumstances where workers were transferred to the sinter plant. The employer argues this transfer was recorded with the designation SP on the time sheets. The employer is also on record as suggesting smelter to sinter plant transfers were common while transfers from other areas of the employers operations were not.
In assessing the worker representative argument for sinter plant exposure I note there is little, if any, objective evidence the worker was employed in the sinter plant. The anecdotal evidence supplied by the worker family and neighbour is unfortunately hearsay at best. While I accept this was the witnesses understanding, they would not have had direct knowledge as to the worker’s actual employment duties. I further note the father of the neighbour who reported working in the sinter plant was apparently on the sinter plant register. While this suggests this person would have had knowledge as to his neighbours work in the sinter plant it also raises the question as to why if the worker in this claim regularly worked in the sinter he would not have been placed on the registry during the extensive review conducted by the employer and union in the 1970’s.
While I respect and understand the union position in respect of the employment records; given the apparently detailed review process conducted jointly by the union and employer in creating the sinter plant registry, the relative timeframes involved, the apparent objective records (time sheets) which provide notations as to when worker’s were assigned to the sinter plant (SP designation), and apparent effort involved in identifying sinter plant workers I have difficulty concluding many years later that workers who were not identified as such at the time can now be accepted as having worked in the sinter based on what must be considered anecdotal evidence. Finally, despite the union concerns regarding the Time Book Registry and the fact such a document may have existed it cannot now be known what information was contained in this record. In the absence of these records I am unable to reach any conclusion as to what they may have contained. Rather, in my view decisions must be guided by the evidence which is available for decision-makers to consider. In summary, while I appreciate the union concerns I find it most appropriate to ascribe the greatest weight to the objective documentation from the period in question and the subsequent work performed in developing the sinter plant registry. While it is or course possible certain workers, as it were, may have fallen through the cracks, I cannot in my view conclude that the absence of evidence creates a presumption for inclusion. Rather, if anything, it would be appropriate to presume the worker did not have sinter plant exposure unless the contrary can be shown.
For these reasons I am unable to conclude that on the balance of probability the evidence establishes the worker spent any significant time employed in the sinter plant.
2) Asbestos Exposure
The worker representative notes the worker spent many years working in the milling operation where he suggests there was significant asbestos exposure, particularly during the zincing process in which the worker was extensively involved. The representative also notes additional exposures in the form of general air quality in the mill and potential cross-contamination of clothing and as a result of historically poor hygiene practices. The representative notes from 1971 to 1976 the worker was a supervisor in mill and suggests the worker would have had significant asbestos exposure at the time. The representative acknowledges this was a 5 year exposure while the policy identifies 10 years as the standard but suggests this time criteria is not black and white. The representative suggests the subsequent medical reporting is suggestive for bio-markers consistent with asbestos exposure. Finally, the representative suggests while the worker was not on an asbestos surveillance program it is important to note the worker was a supervisor, therefore on staff, and to register for such a program would have been to admit concerns about the work environment.
The employer suggests a review of the asbestos monitoring data provides no indication of asbestosis and while the treating doctors took in the worker’s entire history they did not reference bio-markers for asbestos. Finally, the employer notes the worker was never on an asbestos surveillance program.
While I do not dispute the worker representative position the relevant policy is open to interpretation I do consider the science behind the asbestos policy relatively clear. That is, that there is an identifiable dose response to asbestos exposure which forms the basis for the exposure levels identified in policy. In this respect it is appropriate in my view to have regard for the exposure timelines identified in policy. To accept entitlement on this basis it is therefore necessary for the evidence to establish a basis to refute the policy requirement.
A review of the record indicates the WSIB hygienist did not address asbestos exposure but limited his assessment to nickel, arsenic, and silica exposure. The hygienist identified little evidence for significant nickel and arsenic exposure but did suggest excessive silica dust exposure was possible. The employer evidence on file suggests exposure levels with within acceptable standards in 1979 and from 1977 to 1986. A WSIB medical consultant then reviewed the issues of silicosis and asbestos. The consultant suggested the exposure information on file did not support asbestos exposure and noted no evidence of silicosis or asbestosis.
I note there is no detailed assessment of asbestos exposure on file. I further note the worker representative argument for significant asbestos exposure relates to a specific 5 year period. While I appreciate the argument as to the worker not being on the asbestos registry owing to his position on staff this simply means there was an absence of surveillance evidence during the period in question. Once again I am unable to conclude the absence of evidence can be considered to lead to entitlement. However, given the subsequent medical reporting it is possible to assess probable asbestos exposure based on the medical records. In this respect the worker representative has argued pleural thickening is a bio-marker for asbestos while the employer has suggested this would not be the case. I also note the WSIB medical consultant suggested the clinical findings indicated there was no evidence of asbestosis.
While I do not consider a formal diagnosis of asbestosis to be a required precursor to accepting lung cancer as a result of asbestos exposure I do find it appropriate to consider the medical reporting addressing the objective findings prior the acute disease onset.
The worker representative has argued for evidence of pleural thickening as providing bio-markers for asbestos exposure. The employer has argued there are no bio-markers for asbestos present. It is my understanding pleural thickening may reflect a number of health conditions in addition to the effects of asbestos exposure. Given the smoking history, indication of subcutaneous emphysema and the fact all assessments were conducted while the worker was experiencing acute effects from his diagnosed moderately differentiated squamous cell carcinoma and in the absence of any specific medical reference to findings directly attributable to asbestos I do not find the medical reporting suggests a relationship to asbestos exposure. I note there is no indication of asbestosis itself, or identification of pleural plaques or other lesions associated with asbestos, and no indication of biopsy results confirming asbestos fibres.
Therefore, while I acknowledge the worker may have had some asbestos exposure there is in my view no objective confirmation of significant asbestos exposure. More significantly, I do not interpret the medical reporting to suggest a relationship between the diagnosed lung cancer and prior exposure to asbestos.
For these reasons I am unable to conclude entitlement is in order on the basis of asbestos exposure.
3) Relative Contribution of Employment Related Exposure and Smoking History as Causal Factors for the Development of Lung Cancer
The worker representative has acknowledged the smoking history and suggested that if the work exposure is comparatively equal in weight to the smoking history then Benefit of Doubt would apply and entitlement is in order. The employer suggests that when one considers the issue of relative risk as described in the July 23, 1996 memorandum of Dr. Gribbin on record the case should remain denied.
In review the smoking history I note the record confirms a 50 year pack history. I further note the epidemiologist (Dr. Gribbin) reported such a pack year history was consistent with a greater than 30 fold incidence for smokers with the type of cancer diagnosed in this instance. While I appreciate there can be no one answer as to the specific cause for a particular incidence of cancer I must conclude that in this instance I am satisfied that on the balance of probability the worker’s condition has not been shown to be causally related to workplace exposures. I find the evidence insufficient to establish that workplace exposure to asbestos, arsenic, soluble nickel, or silica is shown to be a significant contributing factor in the development of the disease.
CONCLUSION
The objection is denied.
DATED March 9, 2011
M. Evans
Appeals Resolution Officer
Appeals Branch