WORKPLACE SAFETY AND INSURANCE BOARD
APPEALS RESOLUTION OFFICER DECISION
DECISION NUMBER: 20090026
OBJECTION BY: Worker’s Estate
EMPLOYER: Participating
REPRESENTATIVES: Worker
HEARING DATE: N/A
ISSUE
On behalf of the worker’s estate the worker representative objects to the February 7, 2007 claims adjudicator decision denying entitlement to WSIB benefits. The worker representative requests the WSIB recognize the workplace was a significant contributing factor in the worker’s condition and accept benefit entitlement.
HOW THE ISSUE ARISES
The worker passed away October 28, 1993 from the effects of lung cancer. The claim was established as part of the Rubber Cluster claim review in 2002. The operations division obtained the medical and employment history and reviewed the relevant records. An occupational hygiene exposure assessment was also completed and reviewed. The claims adjudicator concluded there was limited evidence of a causal relationship to the employment and the evidence was not sufficient to establish entitlement. The worker representative has objected to this conclusion.
AUTHORITY
11-01-01 – Adjudicative Process
11-01-02 – Decision Making
11-01-03 - Merits and Justice (Decisions related to occupational disease)
Section 13(1) - Workplace Safety & Insurance Act
RESOLUTION METHOD AND PROCESS
The worker representative agreed to proceed to a decision based on the evidence on record and submissions provided.
ASSESSMENT OF THE EVIDENCE
Submissions
The representative suggests the relevant question is whether it is more probable than not the workplace exposures made a significant contribution to the development of the disease. The representative suggests while there is an absence of any actual exposure data this should not lead to the assumption there was no exposure. The representative notes the occupational hygienist confirmed probable exposure to nitrosamines, asbestos, and PAH’s.
The representative provided supporting documentation including a reference WSIAT decision and IARC monograph for the Rubber Industry. The representative suggests that based on the WSIAT decision, for the purposes of the WSIB Nitrosamines should be considered carcinogenic and a human health hazard. The representative suggests even with the term “limited” in relation to causal exposures the IARC monograph conclusion of “lung cancer being positively related” is significant to the case.
The representative also provided the NIOSH Hazard Review: Rubber Products and a December 7, 2007 OHCOW report. The representative notes the NIOSH report indicated many studies report excess deaths including lung cancer among rubber workers. The representative also notes the OHCOW report suggests the worker’s employment in the rubber industry would be considered to have significantly contributed to the lung cancer.
The representative notes the only medical opinion addressing the cause of the cancer is the OHCOW report with the question not being put to any other medical practitioner, including a WSIB medical consultant. The representative notes according to the Medical and Occupation Disease Policy branch epidemiologist review there is a lower relative risk of adenocarcinoma associated with smoking than for other types of lung cancers. The representative notes the OHCOW report suggested that despite the worker’s smoking history it would be difficult to ignore his exposure to nitrosamine exposure in his employment. The representative suggests the smoking exposure does not overwhelm the significance of the work exposures. The representative suggests the evidence clearly supports a probable link between 26 years of employment in the rubber industry and cancer, and on the balance of probability the workplace exposures were a significant contributing factor in the development of lung cancer.
Analysis
Section 13(1) of the Workplace Safety & Insurance Act directs that "A worker who sustains a personal injury by accident arising out of and in the course of his or her employment is entitled to benefits under the insurance plan".
When determining entitlement to a disease claim, a decision-maker considers the worker’s clinical condition and exposure at work, the up-to-date clinical and scientific information, any pertinent non-occupational factors, and all relevant policies. In assessing entitlement for industrial diseases which are not defined either by regulation or a specific policy, decision makers must consider entitlement based on the merits of the case. Under these circumstances the evidence must establish that on the balance of probability the employment exposure was a significant contributing factor in the development or progression of the condition.
The representative has provided detailed and extensive submissions. As the representative has noted the record does not contain specific actual exposure data related to the worker although the occupational hygienist confirmed probable exposure to nitrosamines, asbestos, and PAH’s. Unfortunately, the absence of specific exposure information is frequently the case in latency disease claims. In such circumstances entitlement must be considered based on the likely or probable exposures based on more general evidence as to the nature of the employment exposures during the period in which a worker was employed in an industry or a particular worksite.
In assessing the available evidence, the employment history, and the occupational hygienist opinion, I am satisfied there was probable exposure to the substances identified by the hygienist. I note the estimated exposures include routine and high exposure to nitrosamines and low asbestos exposure. The record also confirms a 40 pack year smoking history. The exposure or smoking histories are not in dispute nor unusual given the nature and period of employment.
The medical reporting confirms a diagnosis of malignant neoplasm in February 2003. Unfortunately the worker did not recover from this condition and passed away October 28, 2003. The final diagnosis was a large bronchogenic adenocarcinoma with extensive metastases.
The OHCOW report submitted notes that as with most disease processes the causes of the workers condition are likely multi-factorial. Dr. Pysklywec notes the presence of risk factors associated with the workers age and smoking history but suggests it would be difficult to ignore the contribution of exposures in the rubber industry in causing the lung cancer. The doctor suggests the WSIB review of cancer in the rubber industry implicates lung cancer and for these reasons concludes the employment exposure significantly contributed to causing the lung cancer.
The claim was established as part of the WSIB review of claims established for workers employed in the rubber industry in the Kitchener / Waterloo area. As part of this process the Medical and Occupational Disease Policy (MODP) branch reviewed the available research into the causal association between employment in the tire manufacturing industry and the development of lung cancer. The MODP report concluded an association could be neither identified nor ruled out. While some suggestive evidence of increased lung cancer risk was identified, effectively the evidence in this respect was considered inconclusive.
In assessing the OHCOW report and the MODP review I note Dr. Pysklywec and the MODP interpreted the evidence of a causal relationship somewhat differently. I do not however consider these opinions to diverge in terms of the evidence. Rather, the issue is a matter of how the evidence is to be weighed when considering entitlement.
The representative has argued that on the balance of probability it is more likely than not the workplace exposures were a significant contributing factor in the development of the lung cancer. From my understanding of the case I find I am unable to accept this position at face value. I base this conclusion on my interpretation of the test which must be applied in industrial disease cases which do not fall within the context of a schedule 3 or 4 disease process. In the absence of a schedule 3 or 4 disease process there can be no presumption for entitlement. Rather, the evidence must establish a basis for accepting a causal relationship to the work.
In this instance while I have accepted the exposure history, the MODP review of the epidemiological record did not confirm sufficient evidence for the MODP to conclude the literature identified a causal association between lung cancer and employment in tire manufacturing. While the MODP also concluded this could not be ruled out I can not in my view consider a null result to support entitlement. Rather, the necessary test requires the evidence establish some probability the condition is shown to be causally related.
In addition to the lung cancer issue I also note the initial medical reporting suggested a possible mesothelioma. As this diagnosis was later ruled out and the condition confirmed as an adenocarcinoma there is no basis to consider entitlement for mesothelioma resulting from asbestos exposure.
While there is no dispute as to the nature of the worker’s condition I find I am unable to conclude the evidence establishes this condition was causally related to his employment in the tire manufacturing industry.
CONCLUSION
The objection is denied.
DATED July 28, 2009
M. Evans Appeals Resolution Officer Appeals Branch