Estate of the Worker v. Employer, 2023 CanLII 57737

20230069

REPRESENTED by:

HEARD by:

Kelly Gordon, appeals resolution officer

DATED:

MAY 16, 2023

ISSUE

The estate of the worker, through their representative is objecting to the Occupational Disease (OD) Adjudicator’s decision dated October 9, 2019. In this decision, the OD Adjudicator denied initial entitlement to lung cancer.

BACKGROUND

While adjudicating the worker’s prior claim for Chronic Lymphocytic Leukemia (CLL), a new diagnosis of lung cancer was identified. This claim was established as the worker relates their lung cancer diagnosis to occupational exposures while working with this employer from 1977 to 2006.

In the adjudication of this claim, I note the OD Adjudicator confirmed the worker’s employment history and obtained all relevant medical information. The OD Adjudicator then referred the claim for an Occupational Hygiene (OH) review in order to identify the worker’s occupational exposures. The claim was also referred to an Occupational Medical Consultant (OMC) who reviewed the information on file, and provided a medical opinion regarding the work-relatedness of the diagnosed lung cancer.

The OD Adjudicator considered all of the evidence, and issued a decision dated October 9, 2019. In this decision, the OD Adjudicator states that although the worker was exposed to asbestos while working, the exposure does not meet the policy criteria to allow entitlement to lung cancer due to asbestos exposure. The OD Adjudicator also considered entitlement based on the merits of the claim. However, the OD Adjudicator determined the evidence does not support the worker’s occupational exposures significantly contributed to the development of their lung cancer. Therefore, the OD Adjudicator concluded the worker does not have initial entitlement to lung cancer.

The estate of the worker submitted the Appeal Readiness Form (ARF) dated November 30, 2022, confirming the estate of the worker’s objection to the denial of lung cancer.

The estate of the worker’s objection to the denial of lung cancer entitlement forms the basis of this appeal.

AUTHORITY

Section 2(1) and 15 and Regulations 3 and 4 of the Workplace Safety and Insurance Act, 1997 (the Act)

Operational Policy Manual

Published

11-01-01 Adjudicative Process

16-02-13 Lung Cancer – Asbestos Exposure

11-01-03 Merits and Justice (Decisions related to occupational disease)

November 3, 2008

October 12, 2004

ANALYSIS

For the reasons that follow, I find the estate of the worker does have initial entitlement to lung cancer. In reaching this decision, I have carefully considered all of the available information on file, the estate of the worker representative’s submission, the legislation, and the relevant operational policies.

Attached to the ARF, the representative for the estate of the worker provided a submission dated November 30, 2022. In this submission, the representative states the worker developed CLL in 2005, and entitlement was later granted for CLL in a prior claim. The worker was later diagnosed with lung cancer in 2015, and the worker underwent lung cancer surgery on November 23, 2015. The cancer returned in 2018, and after undergoing treatment, the worker unfortunately passed away on March 13, 2022. The representative refers to the evidence on file that supports the worker had work-related exposures while working for the employer in the rubber manufacturing industry for 29 years. As per the Occupational Health Clinics for Ontario Workers (OHCOW) report, the worker had an occupational exposure to asbestos from 1977 to 1993 while working as a Bias Cutter. From 2000 to 2005, the worker was again exposed to asbestos while working as a laboratory technician. In addition to asbestos, the worker’s employment exposed the worker to nitrosamines, aromatic amines, and polycyclic aromatic hydrocarbons.

To support their position that the worker’s occupational exposures significantly contributed to their lung cancer, the representative refers to the March 28, 2019 medical report provided by Dr. Pysklywec.

Dr. Pysklywec determined the occupational exposures while working in the rubber industry played an important role in causing the worker’s lung cancer. The representative also refers to the findings provided by the International Agency for Research on Cancer (IARC) 100F monograph (2012), as IARC also concluded there is sufficient evidence to support an increased risk of lung cancer among workers in the rubber manufacturing industry. The representative argues that for entitlement to be allowed, the workplace exposures need not be the sole cause of the worker’s condition, but instead the workplace exposures have to be a significant contributing factor. Although the worker does have a significant smoking history, the worker’s employment history consisted of working for almost three (3) decades in the rubber industry, which is an industry known to be associated with risk of lung cancer. Therefore, the worker’s employment in the rubber industry is also a significant contributing factor in the development of their lung cancer. The representative refers to Workplace Safety and Insurance Appeal Tribunal (WSIAT) decisions that allowed entitlement to lung cancer in workers who smoked, and who also had occupational exposures that increased their risk of lung cancer. For the reasons stated above, the representative argues the worker’s employment history significantly contributed to their lung cancer, and initial entitlement should be accepted in this claim.

The employer is not participating in this appeal, and no submissions have been provided for my review.

Occupational disease cases are adjudicated under section 2 (1) and section 15 of the Act and by regulation in Schedules 3 & 4 of the Act. If the disease is not listed in the Schedules and a relevant policy has not been developed, entitlement to benefits and services is determined based on the merits and justice of the case. It must be established that it is more probable than not that the circumstances of the worker’s employment and exposure history significantly contributed to the development of the medical condition being claimed. In this case, Policy 16-02-13 does apply as the worker had occupational exposures to asbestos. Therefore, I have considered this policy in this appeal. As the worker had other occupational exposures during their employment, I have also considered entitlement based on the merits and justice of the case.

Policy 11-01-01 states that a five point check system is used to adjudicate initial entitlement claims. Each point must be satisfied for initial entitlement to be allowed. There must be an employer, a worker, a personal work-related injury, proof of an accident, and compatibility of the diagnosis to the accident or disablement. As this is an occupational disease claim, the issue to be addressed is whether compatibility has been established between the diagnosed lung cancer and the worker’s occupational exposures while working with this employer. I find all other criteria as outlined in this policy has been met.

When determining entitlement to an occupational disease, the worker’s employment history is obtained, and occupational risk factors are identified. The evidence is then reviewed to determine if it is more probable than not that the circumstances of the worker’s employment and exposure history significantly contributed to the development of the medical diagnosis.

Employment History

As per the worker’s statement provided to the OD Adjudicator, the worker reported that prior to 1977; they worked as a laborer for the city (1970 to 1976). The worker also worked as a cleaner for the hospital (1976 to 1977).

The worker and the employer confirmed the worker was hired on August 29, 1977. The worker and the employer also confirmed the worker performed the following jobs:

1977 to 1993 bias cutter operator

1993 to 1995 steellastic operator

1995 to 2000 VMI cutter

2000 to 2006 lab technician

2006 plant closed

From 2006 to 2015, the worker worked as a golf course marshal, and as a school bus driver.

Medical Diagnosis

As per the medical evidence on file, the worker was diagnosed with CLL in 2005, and the worker’s CLL was accepted as work-related in a prior WSIB claim. While under medical surveillance for the CLL, the worker underwent a chest x-ray on July 22, 2015. The results identified a lung nodule, and this led to further investigations. Later in 2015, the worker was diagnosed with lung cancer (squamous cell carcinoma).

Dr. Somerville, a WSIB OMC, reviewed all of the medical evidence, and as confirmed in their memorandum dated May 24, 2019, Dr. Somerville states the medical evidence supports a primary cancer of lung cancer (squamous cell carcinoma).

Dr. Pysklywec, an OMC from OHCOW submitted a report dated March 28, 2019. Dr. Pysklywec refers to the July 22, 2015 chest x-ray that identified a lung nodule, and notes the worker then underwent a CT guided biopsy that identified non-small cell carcinoma, which is consistent with squamous cell carcinoma. Dr. Pysklywec also confirms the diagnosis of lung cancer – squamous cell carcinoma diagnosed in 2015 with a recurrence in 2018.

As there are no medical reports that argue the opinions provided by both Dr. Somerville and

Dr. Pysklywec, I accept the opinions as provided. Therefore, I accept the evidence supports the worker’s primary diagnosis is lung cancer (squamous cell carcinoma).

Smoking history

I find it important to note here that a pack-year is a clinical quantification of cigarette smoking used to measure a person’s exposure to tobacco. A pack-year is defined as twenty cigarettes smoked every day for one year. To calculate a pack-year history, the number of packs of cigarettes smoked per day, is multiplied by the number of years smoked. In this case, there is a discrepancy in terms of the worker’s smoking history. Specifically, the oncologist’s consultation report dated January 18, 2016, indicates the worker reported a smoking history of three (3) packs a day for 40 years (120 pack years). The hospital progress report dated February 19, 2016, also states the worker’s smoking history is 120 pack years. As per the OD Adjudicator’s memorandum dated April 30, 2019, the worker reported they started smoking at age 16 and continued smoking until 2015 when they were diagnosed with lung cancer. The worker advised they smoked ½ pack to one (1) pack per day (50 pack years). As noted in the OHCOW report dated March 28, 2019, the worker reported they started smoking at age 16, and continued smoking until age 56. The worker approximated their smoking at one (1) pack per day.

Noting the discrepancies on file regarding the worker’s smoking history, the OD Adjudicator accepted a 105 pack-years smoking history. This is the average of the reported smoking histories.

Based on the evidence on file, and the calculation used to determine the smoking history, I accept the worker’s smoking history as 105 pack years.

Occupational and Non-Occupational risk factors for the development of lung cancer

In terms of non-occupational risk factors, I note the OMC medical review dated May 24, 2019. The OMC states the following:

“Lung cancer is the most common cancer worldwide, however lung cancer deaths have begun to decline in both men and women, reflecting a decrease in smoking (Jemal et al, 2013). Approximately 95 percent of all lung cancers are classified as either small cell lung cancer or

non-small cell lung cancer. Other cell types comprise about 5 percent of malignancies arising in the lung.”

The OMC goes on to state:

“In men and women, the incidence of lung cancer increases greatly beginning at about the age of 40 years. The incidence in people 50 – 54 years old is double that in people 45 – 49 years old, and it doubles again in those 55 – 59 years old. The development of lung cancer is a multistep process. Genetic damage caused by exposure to a carcinogen such as cigarette smoke sets off the process. The link between tobacco smoke and lung carcinogenesis has been established by molecular data. This risk of lung cancer due to cigarette smoking is one of the most thoroughly documented cause-and-effect relationships in medical science. Second hand smoke is also an established cause of lung cancer. Second-hand smoke has the same components as inhaled mainstream smoke, although in lower absolute concentrations. Cigarette smoking accounts for approximately 90% of lung cancer cases (Alberg and Samet. 2003). Compared with those who have never smoked, cigarette smokers with a 40-pack year history have a 20-fold increase in lung cancer risk. The cumulative lung cancer risk among heavy smokers may be as high as 30 percent, compared with a lifetime risk of lung cancer of 1 percent or less in never smokers

(Samet et al, 1988). The risk of lung cancer from cigarette smoking increases with the number of cigarettes smoked and the duration of smoking.”

In terms of occupational risk factors, I refer to the findings provided by IARC. IARC is an international agency that forms part of the World Health Organization of the United Nations. It is their role to conduct and coordinate research into the causes of cancer. According to IARC, carcinogenic agents with sufficient evidence in humans for lung cancer include the following:

acheson process, occupational exposures associated with aluminium production
arsenic and inorganic arsenic compounds
asbestos (all forms)
beryllium and beryllium compounds, bis(chloromethyl) ether, chloromethyl methyl ether (technical grade)
cadmium and cadmium compounds, chromium (VI) compounds, coal, coal gasification, coal-tar pitch
coke production, engine exhaust, diesel, hematite mining (underground)
iron and steel founding, MOPP (vincristine-prednisone-nitrogen mustard-procarbazine mixture)
nickel compounds
outdoor air pollution, painting, particulate matter in outdoor air pollution
plutonium, radon-222 and its decay products
rubber production industry
silica dust, soot, sulphur mustard
tobacco smoke (second-hand), tobacco smoking
welding fumes, x-radiation and gamma-radiation

Noting the worker worked in the rubber industry for approximately 30 years, I refer to IARC’s monographs – 100F. In this report, IARC states new data has become available regarding occupational exposure in the rubber-manufacturing industry. According to IARC, workers in the rubber-manufacturing industry are exposed to dusts and fumes from the rubber-making and vulcanization processes. Potential exposures include N-nitrosamines, polycyclic aromatic hydrocarbons, solvents, and phthalate. Inhalation is the main route of exposure, although workers may have dermal exposure as well.

In terms of evaluation, the IARC report states the following:

“There is sufficient evidence in humans for the carcinogenicity of occupational exposures in the rubber manufacturing industry. Occupational exposures in the rubber manufacturing industry cause leukaemia, lymphoma, and cancers of the urinary bladder, lung, and stomach.

Iso, a positive association has been observed between occupational exposures in the rubber manufacturing industry and cancers of the prostate, oesophagus, and larynx.”

OH Review

A WSIB OH conducted an OH assessment on June 17, 2019. The assessment report is on file, and confirms all jobs while working for the employer were reviewed. The OH notes the worker was employed in the rubber manufacturing industry for 32 years, from 1977 to 2005. During this period, they were primarily located in stock preparation and the quality control laboratory. The worker’s employment history after 2005 (as confirmed by the OD Adjudicator) primarily involved the operation of a school bus.

The OH focused their review on the worker’s exposure to crystalline silica, rubber process emissions, and asbestos. In addition to the information provided in the claim file, the assessment utilised information from the Ministry of Labour (MOL), and the published literature. The OH refers to the worker’s occupational exposures, and provides the following opinion.

Crystalline silica exposure:

The available job information suggests the worker’s most likely exposure to dust occurred during their tenure in stock preparation from 1977 to 2000. The anticipated work processes in this area coupled with the available air monitoring data suggests the worker’s exposure to respirable quartz silica was likely below the current MOL exposure limit of 0.1 mg/m3 from the 1980s onwards. Due to less stringent MOL regulations, airborne exposures to quartz prior to this date could have been higher; information to further characterise these exposures was not available.

Robber process emissions exposure:

The worker was employed in the rubber manufacturing industry from 1977 to 2005. In general, workers in the rubber tire manufacturing sector are potentially exposed to broad categories of agents, i.e. rubber fume and rubber process dust. Dost et al. (2000) 2 described rubber fumes as being generated by heated processes, such as milling, extrusion, calendering, and curing of natural rubber or synthetic elastomers, or of natural rubber and synthetic polymers combined with chemicals, and in the processes which convert the resultant blends into finished products or parts and include any inspection procedures where fume continues to be evolved. The authors further described rubber process dust as the mixed dust arising in the stages of rubber manufacture where ingredients are handled, weighed, added to or mixed with uncured material or synthetic elastomers. These dusts did not include dust arising from the abrasion of cured rubber.

Robber process emissions exposure (continued):

The worker’s employment records noted work in areas containing heated processes, e.g. extruders during his tenure as Stellastic Operator from 1993 to 1995. It is likely that during a portion of his 28 years in the rubber factory the worker was exposed to rubber process emissions, i.e. rubber fumes, while working at or in proximity to heated rubber processes, such as extruders. The nature of the worker’s duties suggest his exposure to rubber process emissions was likely below those of co-workers working directly with other heated rubber processes, such as Banbury mixers or cure presses.

Asbestos exposure

A review of the worker’s employment records did not suggest any of his duties involved work with asbestos materials or insulation. As such, it is not anticipated he was exposed to noteworthy levels of airborne asbestos during his tenure in the rubber tire manufacturing industry.

OHCOW and OMC reviews

Dr. Pysklywec, OMC for OHCOW submitted a claim review dated March 28, 2019. In this review,

Dr. Pysklywec notes the worker was diagnosed with CLL in 2005 and lung cancer (squamous cell carcinoma) in 2015. Dr. Pysklywec states both of these cancers have been identified by IARC as being related to work in the rubber industry. A number of carcinogens are identified in this industry. These include nitrosamines, polyaromatic hydrocarbons (PAHs), aromatic amines, potential asbestos and potential benzene. During their almost 30 year employment in the rubber manufacturing industry, the worker would have been exposed to rubber fumes, asbestos from ambient plant conditions as well as solvent exposure including potential benzene from chemical sprays. In addition to the findings provided by IARC, Dr. Pysklywec refers to multiple other studies that support an association between the rubber manufacturing industry and lung cancer. While Dr. Pysklywec recognizes the worker has a significant smoking history, and accepts that their smoking history likely contributed to their lung cancer,

Dr. Pysklywec states it is difficult to quantify the relative effects of smoking versus occupational exposures. Dr. Pysklywec concluded the following:

“Given his occupational and medical history, it is my impression that his work contributed to both his lung cancer and CLL. Notwithstanding his smoking history, the worker worked for almost 3 decades in an industry that has been linked to lung cancer. The medical literature consistently reports elevated risk of lung cancer in the rubber industry.”

Dr. Somerville, WSIB OMC conducted a medical claim review on July 24, 2019. Based on their review of the evidence, Dr. Somerville states the worker’s age (66 years old at time of diagnosis), and their smoking history puts the worker at greatly increased risk for lung cancer. Additionally, Dr. Somerville states that cancer is more likely in individuals previously diagnosed with cancer, and at the time of the worker’s lung cancer diagnosis, the worker was under surveillance for CLL that was diagnosed in 2005. Dr. Somerville refers to the OH assessment, and notes the worker was potentially exposed to high levels of benzene for three (3) years as a bias cutter, and low levels of benzene in their subsequent 12 years. Dr. Somerville also refers to the findings provided by IARC, and states IARC lists benzene as an agent with limited evidence in humans with respect to lung cancer. Specifically, the OH assessment notes the worker’s routine exposure to crystalline silica after the 1980s was likely well below the current MOL exposure limit of 0.1 mg/m3.

In terms of the worker’s exposure to rubber process emissions, Dr. Somerville states that a portion of their tenure in the rubber industry likely involved work with or in proximity to heated processes. However, the nature of their duties suggest their rubber process emissions exposure was likely below those of

co-workers working directly with heated rubber processes, such as Banbury mixers or cure presses.

Dr. Somerville also determined it was not likely the worker was exposed to noteworthy levels of airborne asbestos in the rubber manufacturing industry, or to other agents of interest, namely welding fumes, arsenic, cadmium, chromium, and nickel. Given the information provided in the OH assessment, and noting the worker’s non-occupational risk factors, Dr. Somerville concluded the workplace exposures were likely not important contributors to the development of the worker’s lung cancer.

Prior claim for CLL

In my review of the evidence, I note the decision dated June 19, 2019, in the worker’s prior claim. As per this decision, the OD adjudicator accepted that it was more probable than not that the worker’s occupational exposures while working in the rubber manufacturing industry significantly contributed to the worker’s diagnosed CLL. Therefore, the OD Adjudicator allowed entitlement to CLL in the prior claim.

Has the criteria as outlined in Policy 16-02-13 Lung Cancer – Asbestos Exposure been met?

For the reasons that follow, I find the criteria in Policy 16-02-13 has not been met. Therefore, I do not find the worker’s lung cancer is due to an occupational exposure to asbestos.

As per Policy 16-02-13, lung cancer in asbestos workers is accepted as an occupational disease under sections 2(1) and 15 of the Workplace Safety and Insurance Act as peculiar to and characteristic of a process, trade or occupation involving exposure to asbestos.

Based on medical studies, lung cancer claims are favourably considered when the following circumstances apply:

there is a clear and adequate history of at least 10 years occupational exposure to asbestos, and
there is a minimum interval of 10 years between first exposure to asbestos and the appearance of lung cancer.

Claims, which do not meet these guidelines, will be individually judged on their own merit, having regard for the intensity of exposure and other factors peculiar to the individual case.

In reviewing the worker’s exposure to asbestos, I refer to the OH assessment. As per the OH review, the worker’s occupational exposure to asbestos is noted as follows:

“A review of the worker’s employment records did not suggest any of his duties involved work with asbestos materials or insulation. As such, it is not anticipated he was exposed to noteworthy levels of airborne asbestos during his tenure in the rubber tire manufacturing industry.

Based on my review of the evidence, I do not find a clear and adequate history of at least 10 years of occupational asbestos exposure. In making this determination, I have placed significant weight on the June 17, 2019 OH assessment. The OH’s review is based on information provided in the claim file, and information provided by the MOL, and published literature. The OH specifically refers to the worker’s occupational exposure to asbestos, and states the evidence does not support the worker’s duties involved work with asbestos materials or insulation.

As there are no OH opinions on file that argue the findings as provided by the WSIB OH, I have accepted the findings as provided. Therefore, as I have accepted the opinion as provided by the OH, I find the evidence supports the worker did not have a clear and adequate history of at least 10 years of occupational asbestos exposure. As such, I find the criteria as outlined in Policy 16-02-13 has not been met.

For the reasons stated above, I find the worker does not have entitlement to lung cancer under

Policy 16-02-13.

Does the evidence support lung cancer under the Merits and Justice Policy?

For the reasons that follow, I find the worker’s occupational exposures significantly contributed to the development of their lung cancer. As such, based on the merits of the claim, I find the worker does have entitlement to lung cancer.

Policy 11-01-03 states that 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 of the relevant policies.

In terms of the OH assessment, I find it important to note that the OH reviewed the worker’s occupational exposures while working in the rubber manufacturing industry from 1977 to 2005. The OH confirms that in general, workers in the rubber tire manufacturing sector are potentially exposed to broad categories of agents, i.e. rubber fumes, and rubber process dust. The OH states rubber fumes are generated by heated processes, such as milling, extrusion, calendering, and curing of natural rubber or synthetic elastomers, or of natural rubber and synthetic polymers combined with chemicals. The processes convert the resultant blends into finished products or parts and include any inspection procedures where fume continues to be evolved. While I note the OH states the nature of the worker’s duties suggest their exposure to rubber process emissions was likely below those of co-workers working directly with other heated rubber processes, I find it significant that the OH states the worker’s employment records confirm the worker worked in areas containing heated processes. The OH goes on to state that it is likely during their 28 years in the rubber factory the worker was exposed to rubber process emissions.

I have also placed weight on Dr. Somerville’s medical review dated July 24, 2019. I specifically note that Dr. Somerville states cancer is more likely in individuals previously diagnosed with cancer, and at the time of the worker’s lung cancer diagnosis, the worker was under medical surveillance for CLL that was diagnosed in 2005. I find this significant as the worker claimed their CLL was a result of occupational exposures while working in the rubber industry. As confirmed in the decision dated June 19, 2019, the OD Adjudicator accepted the worker’s occupational exposures significantly contributed to their diagnosed CLL, and granted entitlement to CLL. Therefore, according to Dr. Somerville, the worker’s compensable CLL also likely contributed to the worker’s diagnosed lung cancer.

In determining entitlement to lung cancer in this claim, I have placed the most weight on the findings as provided by IARC. IARC is a worldwide organization, and their role is to conduct and coordinate research on the causes of cancer. IARC has researched the exposures to workers in the rubber manufacturing industry, and found there is sufficient evidence in humans for the carcinogenicity of occupational exposures in the rubber manufacturing industry. Specifically, IARC states occupational exposures in the rubber manufacturing industry are linked to lung cancer.

I find it important to note that I do not question the evidence on file supports the worker has a significant smoking history, and that the worker’s smoking history significantly contributed to their diagnosed cancer. I also do not question the evidence supports the worker’s age at time of diagnosis significantly contributed to their diagnosed lung cancer. However, I cannot disregard the evidence before me that supports the worker had occupational exposures while working in the rubber manufacturing industry for almost 30 years, and these occupational exposures also significantly contributed to their diagnosed lung cancer.

I also find the evidence supports the worker’s compensable CLL increased the worker’s risk for developing another cancer. As such, I find the evidence supports the worker has both non-work-related and work-related exposures that significantly contributed to their diagnosed lung cancer. Section 2 (1) and section 15 of the Act state that for entitlement to be allowed, it must be established that it is more probable than not that the circumstances of the worker’s employment and exposure history significantly contributed to the development of the medical condition being claimed. In this case, although I find the worker’s non-work-related risk factors significantly contributed to the diagnosed lung cancer, I also find the worker’s employment and exposure history significantly contributed to the development of their lung cancer.

In summary, I find the worker’s occupational exposures significantly contributed to the worker’s diagnosed lung cancer. I find the criteria as outlined in Policy 11-01-01 has been met. Therefore, I find the estate of the worker does have initial entitlement to lung cancer in this claim.

CONCLUSION

I find the estate of the worker does have initial entitlement to lung cancer.

The estate of the worker’s objection is allowed.

DATED May 16, 2023

Appeals Resolution Officer

Appeals Services Division