Worker's Estate v. Employer, 2009 CanLII 80156

WORKPLACE SAFETY AND INSURANCE BOARD

APPEALS RESOLUTION OFFICER DECISION

DECISION NUMBER: 20090089

OBJECTION BY: Worker’s Estate

WORKER: Worker’s Estate Participated

REPRESENTATIVE: Worker

EMPLOYER: Participated

DECISION WITHOUT A HEARING

ISSUES

1. Entitlement to recognize that the worker’s occupational exposures as a firefighter were a significant contributory factor in the development of colorectal cancer.
2. Entitlement to survivor benefits.

HOW THE ISSUES ARISE

The worker was born in 1940. He was employed as a full time firefighter with the employer from February 10, 1964 until he retired on September 8, 1978. Subsequent to his retirement he was self employed as a landscaper in the summer and doing snow removal in the winter for a 22 year period.

A claim was established with the WSIB by the firefighters association on behalf of the worker’s spouse, on August 17, 2007. The worker had been diagnosed with colon cancer with metastses to the liver, and passed away on October 26, 2003.

Inquiries were conducted into the worker’s work history and occupational exposures, and medical information was requested. The family doctor confirmed that the worker first presented with symptoms and sought medical attention on February 11, 2003, and this was considered the date of accident.

The employer confirmed the worker’s employment as a full time firefighter from February 1964 – September 1978. However, there were no details provided regarding the worker’s individual fire fighting history.

The Fire Fighter Intake Checklist was completed by the worker’s spouse confirming that he also worked as a TV tower installer during the period he worked as a firefighter. It is also noted that he smoked for three years from 1971 – 1974, and there was no family history of similar medical problems. In response to the question of whether there were any memorable incidents of smoke inhalation or chemical exposure, the Dow Chemical fire is noted.

All of this information was reviewed by the claims adjudicator. It was noted that as the worker was diagnosed with colon cancer after his 61st birthday, the circumstances did not meet the legislative requirements of Bill 221, and Operational Policy 23-02-01 Cancer in Full Time Firefighters. The legislation and policy state that the minimum duration of employment for colon cancer is 10 years, and also that the diagnosis must occur prior to age 61. Therefore, the case was adjudicated on its own merits in accordance with Occupational Disease Advisory Panel (ODAP) principles.

The adjudicator noted that the worker did meet the exposure criteria, having been employed as a full time fire fighter for 14 ½ years. However, noting medical attention was sought for related symptoms in February 2003, and the diagnosis was confirmed by colonoscopy on May 15, 2003, the worker did not meet the criteria of a diagnosis prior to age 61. It was also noted that although he supposedly fought a large fire at Dow Chemical, no details were provided regarding the date of this fire or the type and duration of exposure involved.

The adjudicator determined that the evidence was not persuasive to conclude that it was more probable than not that the worker’s occupational exposures were a significant contributing factor in the development of colorectal cancer. Entitlement was denied as outlined in the February 28, 2008 letter.

The claim was referred to the Appeals Branch, and I discussed the issues with the worker’s representative. We agreed to proceed via written submissions, and a submission dated April 15, 2009 was provided. The employer elected to participate, and provided a submission dated May 19, 2009.

The decision will be made based on the information in the claim file record, and the workplace parties’ submissions.

AUTHORITY REFERENCE

Sections 2 and 15 Workplace Safety and Insurance Act 1997

Regulation 253/07 Presumptions for Firefighters – Workplace Safety and Insurance Amendment Act 2007

Operational Policies:

23-02-01 Cancers in Full Time Firefighters

11-01-03 Merits and Justice

ASSESSMENT OF THE EVIDENCE AND SUBMISSIONS

In reviewing the issue before me, I have considered all of the information in the claim file record, the workplace parties’ submissions, and the relevant policy and legislation. I conclude that the balance of evidence does not support that the worker’s exposures as a firefighter were a significant contributory factor in the development of colorectal cancer.

Workplace Parties’ Submissions

The worker’s representative outlined his position in his submission dated April 15, 2009. Attached to his submission he provided:

• A scientific review prepared by Dr. Xuguang Tao for the WSIB entitled Literature Review and Meta-analysis on Colorectal Cancer Risk and Firefighting, dated October 2005.

• A summary of Dr. Tao’s report dated March 29, 2006.

• An Adjudicative Support Information document entitled Colon and Rectal Cancer Risks and Firefighting, dated March 29, 2006.

• A copy of Operational Policy 23-02-01 Cancers in Full-Time Firefighters.

• A copy of Ontario Regulation 253/07 Firefighters.

• A copy of an email pertaining to the Bates Chemical Fire.

In his submission, the representative noted that the worker’s employment as a firefighter for 14 ½ years has been confirmed, and he was exposed to the many known toxic substances present when fighting fires. The worker was employed during an era when the use of self contained breathing apparatus was not consistent and the type used by his department was faulty and leaked. As well, as he worked in a small department, all on duty staff likely responded to fire calls.

The representative also noted that the Dow Chemical fire referred to was actually the Bates Chemical fire. He provided a copy of an email from a former firefighter who attended this fire and corroborated that the worker also attended. The representative noted that a list of approximately 12 firefighters who attended this call revealed that three were still alive, one with terminal cancer. The others were deceased from various cancers. Further information including; the names of these co-workers, their work history, and whether claims were initiated with the WSIB was not provided.

The fire occurred on September 23, 1977, and the firefighters were on scene for 11 hours, with a second response the following afternoon. The representative feels this fire represented a significant and unusual exposure for the worker.

The representative also noted that although the diagnosis did not occur prior to age 61, it was likely present prior to age 61,noting that the cancer was at stage four at the time of diagnosis. The worker was age 62 years and 4 months at the time of diagnosis. He referenced the adjudicative support information which supports that it may have taken some 20 years to advance to a symptomatic stage, and thus the cancer was present prior to age 61.

It was noted that the worker left the fire department in 1978, and was diagnosed in 2003,

25 years after he left the department. Based on the thought that it takes 20 years for a solid tumor to grow, it is highly plausible that the carcinogenic exposures that occurred during his employment, began to grow into a tumor soon after he ceased working for the fire department.

The representative referenced the legal principles of decision making, The Occupational Disease Advisory Panel (ODAP) Report, The Bradford Hill Criteria, Section 119(2) of the Act pertaining to benefit of doubt, and Operational Policy 11-01-03 Merits and Justice. It is his position that the worker’s exposures as a firefighter were a significant contribution to the onset of primary colon cancer.

The employer outlined their position in a submission dated May 19, 2009. The employer noted that there is limited information provided regarding the worker’s past medical history. The only information provided is from the family doctor, in the report dated October 31, 2007. This report notes that the worker first sought treatment for gastric problems in February 2003.

The employer noted that colorectal cancer is the second leading cause of death from cancer. One in 14 men is expected to develop colorectal cancer during their lifetime, and one in 31 will die of it. This information is based on Canadian Cancer Statistics 2005.

The employer provided an analysis of Dr. Tao’s report, noting that the Standard Incidence Ratio (SIR) summarized the relative risk for colon, rectal, and colorectal cancer at 1.08, 1.29 and 1.13 respectively, none of which is statistically significant.

When reviewing the Standardized Mortality Ratio, colon cancer did not show a significant association with overall firefighting, although there were two studies which demonstrated significant associations. In reviewing Table 5, the probability of getting colorectal cancer from firefighting ranged from 11.8% to 23.6%.

The analysis also demonstrated that the average relative risk of developing or dying from colorectal cancer increases with years services, reaching 1.6 at the highest level after 40 years of exposure. The attributable risk fraction to firefighting would reach 36% at the highest level after 40 years of exposure. It is the employer’s position that the worker’s 15 years would be insignificant and other factors outside of the workplace must be a contributing factor in the onset of the worker’s colon cancer.

In mortality studies, the relative risk was below 1.5 in the worst scenario. Colon cancer did not show significant association with firefighting. Although two early studies did show elevated colon cancer risks among firefighters, this effect was diluted by later large scale studies. The attributable risk fraction analysis suggested that colorectal cancer in firefighters might at most have a 24% probability of being associated with firefighting.

Dr. Tao concluded that the incidence studies published so far did not show any significant association between firefighting and cancer of the colon and rectum, or colorectal cancer combined. As well, the pooled analysis also failed to reach a level of statistical significance.

Dr. Tao also notes that when looking at individual cases, information on other risk factors such as; age, family history, smoking, etc. need to be obtained. As well it is important to be aware of background levels of colorectal cancer risk in the area of residence. For instance, the probability of a work relationship with firefighting would also be increased in the individual who is young, not a smoker, without a family history of colorectal cancer, is not obese, and resides in a geographical area with a low rate of colorectal cancer.

The worker was over 62 when diagnosed. The family doctor’s October 31, 2007 report confirms that the worker’s brother had been diagnosed with cancer, and he was a past smoker. Prior to being diagnosed he weighed 238 lbs in September 2002, and resided in an area of high incidence of colorectal cancer. This would indicate that he has a high number of risk factors outside of firefighting.

The employer notes that as the worker was 62 years and 4 months at the time of diagnosis, he does not meet the criteria for consideration under the presumptive legislation under Bill 221. It is their position that based on the evidence on file, the balance of probabilities would suggest that the worker’s cancer was due to none work- related factors.

Analysis

In reaching my conclusions, I have considered all of the available information, the positions of the workplace parties, and the relevant policy and legislation. In weighing the balance of probabilities, I conclude that the evidence does not support that the worker’s exposures as a firefighter were a significant contributing factor in the development of colon cancer.

In adjudicating claims for occupational disease, if the disease is not listed in Schedule 3 or 4, and there is no relevant WSIB Operational Policy, the claim is adjudicated on its own merits, in accordance with Occupational Disease Advisory Panel (ODAP) principles.

In these circumstances, the decision maker must be satisfied that in weighing the balance of probabilities, it is more likely than not that an individual’s workplace exposures were a significant contributing factor in the onset of the illness/disease.

The decision maker gathers and reviews information pertaining to the worker’s individual medical history, employment and exposure history, and considers this in conjunction with the most recent scientific information available. Adjudication of individual claims should require consideration of a number of types of evidence where available including; employment history, hygiene exposure assessments, third party observations and anecdotal reports, as well as scientific evidence. Establishing causation for a disease does not have to be done with scientific certainty. Rather, the causal link between the workplace and disease must be established using the legal standard, which is, based on the balance of probabilities, taking into account all of the evidence.

In this case, there is legislation and operational policy which applies to colorectal cancer and firefighters. Ontario Regulation 253/07 Firefighters, provides a presumption that the prescribed cancers listed are work-related occupational diseases. To qualify for this presumption, workers must meet the inclusion criteria set out in the regulation, and Operational Policy 23-02-01 Cancers in Full-Time Firefighters. As it pertains to primary site colorectal cancer there must be 10 years duration of firefighting, and the diagnosis must occur prior to the worker’s 61st birthday.

Workers not meeting the inclusion criteria, and those excluded from this policy, will have their claims determined on their individual merits. As well, the presumption may be rebutted if it is established that the employment was not a significant contributing factor to the occurrence of the cancer. In this case, as the worker was diagnosed subsequent to his 61st birthday, the claim is considered on its own merits.

In reaching my conclusions, I have afforded significant weight to Dr. Tao’s literature review and meta-analysis. Dr. Tao is an epidemiologist from John Hopkins University, and conducted a thorough review of the published literature on the occupational risk or colorectal cancer from firefighting.

Dr. Tao’s review referenced the geographical trend from the Canadian Cancer Statistics 2005. I have reviewed this, as well as the updated statistics from 2009. The 2009 statistics are similar to the 2005, noting the colorectal cancer incidence and mortality rates are higher in eastern provinces, and lower in western Canada. The worker lived in Durham Region. The Ontario incidences were lower than the eastern provinces, but higher than the western provinces. Of note, a comparison report prepared by the Durham Region Health Department notes that the Age Standard Incidence Ratio (SIR) for colorectal cancer is slightly higher than the average for Ontario at 1.03.

Dr. Tao’s conclusions have been discussed previously, and are as follows:

1. The reviewed incidence studies did not report a significant association between firefighting and cancer of the colon and rectum or colorectal cancer combined, and the pooled analysis also failed to reach a level of statistical significance.
2. Mortality studies revealed statistically significant low excess risks of rectal cancer and colorectal cancer with firefighting exposure. The relative risk was below 1.5 in the worst scenario. Colon cancer did not show a statistically significant association with firefighting.
3. The attributable risk fraction analysis suggests that at most 24% of colorectal cancers in firefighters may be associated with firefighting work.
4. The analysis of the summary relative risks by duration suggests that the mortality risk of colon cancer slightly increases with increasing duration of employment with the summary relative risk estimated at 1.6 for the highest level of exposure (40 years), but this trend was not statistically significant. The attributable risk fraction for firefighting would reach its highest at 36% for 40 years of exposure.
5. The above conclusion was based on a pooled analysis or eligible studies and reflects the average risk level for colorectal cancer for the entire firefighter population. It should not be applied directly to individual firefighter cases.
6. For individual cases, information on other risk factors such as age, family history, smoking, etc. need to be obtained. In addition, it is important to be aware of background levels of colorectal cancer risk in the area of residence. For instance, the probability of a work relationship with firefighting would also be increased in the individual who is young, not a smoker, without a family history, is not obese, and resides in a geographical area with a low rate of colorectal cancer.

Dr. Tao’s report provides common risk factors for colorectal cancer as per the American Cancer Society, and the relative risks associated with these factors. These include; a family history of colorectal cancer in a first degree relative, familial colorectal cancer syndromes, race/ethnic background, a history of colorectal polyps, a history of chronic inflammatory bowel disease, aging as the chances of developing colorectal cancer increase markedly after age 50 with 90% of people diagnosed being older than 50, a diet mostly from animal sources high in fat and red meats, physical inactivity, obesity, diabetes, people with diabetes have a 30% to 40% increased chance of developing colorectal cancer, smoking, and alcohol intake.

The information pertaining to the worker’s personal medical history is limited. However, the family doctor’s report does confirm a diagnosis of colon cancer in the worker’s brother, which was not disputed in the representative’s submission. The worker weighed 238 lbs in September 2002 prior to diagnosis, and he was on medication for diabetes and hypertension. The family doctor notes he was a non-smoker, and non-drinker. However, he was a past smoker from 1971 – 1974. The family doctor and representative did not provide further details of the worker’s physical activity levels and diet. However, diet and insufficient physical activity are risk factors in developing obesity, hypertension, and diabetes.

The worker’s representative provides his position that the 14.5 years firefighting, and the Bates Chemical fire exposures, were significant in the worker’s development of colon cancer. He also notes that the fact that it takes 20 years for a solid tumor to become clinically detectable, and that the worker was diagnosed at stage 4, the cancer likely occurred before age 61. It is his position that a colon tumor was present prior to age 61, and that the relationship to work was significant in nature.

I have considered the representative’s position on this point. It is his position that the carcinogenic exposures that occurred during his years as a firefighter began to grow into a tumor soon after he ceased working for the fire department. He also feels that the chemical assault at the Bates Chemical fire which occurred in 1977 played a significant role in the development of the colon cancer.

The worker first presented with symptoms in February 2003, 24.5 years after he left the fire department, and 25.5 years after the Bates Chemical Fire. It is generally accepted that most solid malignant human tumors require 20 years to develop before becoming clinically detectable. Therefore, if the firefighting exposures were a significant factor, one would expect symptoms to occur in 1997 or 1998. However, I do acknowledge that the worker was at stage 4 at the time of diagnosis in 2003.

The worker was self-employed as a landscaper in the summer and performing snow removal in the winter for a 22 year period after he left the fire department. There has been no information provided regarding his exposures as a landscaper, whether he was involved in chemical spraying, and whether he wore personal protective equipment.

In summary, I find that the worker’s firefighting exposures were not a significant contributory factor in the development of colon cancer. The scientific literature does not support a statistically significant risk based on his employment duration. The relative risks associated with his other known risk factors of; positive family history, obesity, past smoking, age, and diabetes are significant.

CONCLUSION

After careful consideration, in weighing the balance of probabilities, I find that the balance of evidence does not support that the worker’s exposures as a firefighter were a significant contributing factor in the development of colon cancer.

The objection on behalf of the worker’s estate is denied.

DATED August 27, 2009 at Toronto, Ontario.

D. McParland

Appeals Resolution Officer

Appeals Branch