Figure 1: Visual of how much asbestos containing dust from friction linings becomes airborne when cleaning with compressed air. Source: Rohl et al. 1976 (Figure 4).

Background

The claimant worked on heavy mobile equipment from 1956-1998, servicing brakes and clutch pads and gaskets known to contain asbestos. He stopped working in 2003 after being diagnosed with colorectal cancer.

The WSIB Ontario policy (16-02-11) recognizes an association between asbestos exposure and colorectal cancer. However in the 2019 WSIB decision, the claimant's exposure was described as "moderate" and did not meet the criteria to have caused his cancer. His claim was denied.

Intervention

The claimant's exposure period, especially from 1956 until the mid-1980s, covered a time when exposure controls were sub-optimal as compared with today’s standards. No personal protective equipment (PPE), such as masks, were provided by the employer.

An OHCOW review found evidence that the claimant's exposure was more than moderate. OHCOW focused on asbestos exposure while also addressing diesel engine exhaust and varsol, both substances associated with colorectal cancer. Detailed analysis of the process of the claimant's work conducting brake line inspection, maintenance, and part replacement was included, meticulously breaking down exposures during a typical shift.

Previous studies cited in the OHCOW report showed that exposures to these substances were elevated when using compressed air, which was used in the workplace to clean up residual dust from friction lining products including worn clutch and brake pads.  Maintenance and repair of diesel-powered equipment was often carried out indoors, also elevating exposure to diesel exhaust.

Due to the fact that he repaired many vehicles indoors, the worker's "cumulative exposure to diesel particulate matter (DPM)  from 1956 was elevated." Varsol, used as a degreaser in the brake maintenance process, was also a factor. In the 1950s and 60s, within the timeframe of the claimant's employment, varsol contained benzene and toluene, when the dangers were not known. Both are associated with rectal cancer.

OHCOW Impact

The report demonstrated consistent, elevated exposures, above the current occupational exposure limit.

Once the final (systematic literature) report is released by the WSIB, it is likely that this will open the door to revisit previously rejected claims. This means that all forms of gastro intestinal cancer with “elevated” asbestos exposure, including those who serviced vehicle brake and clutch pads using compressed air which is a common practice, should be awarded compensation for “all forms” of GI cancer.

Background

OHCOW ergonomists are contacted by employers to assist with workstation assessments in a variety of occupational sectors. They evaluate workstations based on the user’s anthropometrics, needs, duties, setup, and equipment present. This year, four distinct workstations were assessed at different workplaces, including a greenhouse packing line, pathologist laboratory, piano studio, and reception area. Workers at these workstations were experiencing musculoskeletal discomfort in the upper and/or lower extremities because of their setup and occupational duties. Below are the four workstations:

Greenhouse Packing Area	Pathologist Laboratory
Piano Studio	Reception Area

Intervention

Three of the workstations were used by one employee (pathologist, piano instructor, and receptionist) and for each of these the OHCOW Ergonomist had the worker take photographs, complete a questionnaire to identify their current discomforts; equipment used; and the daily duties required.  Telephone correspondence with the health and safety representative at the greenhouse for the packing operation was conducted prior to the worksite visit to understand the process and concerns. This information allowed the ergonomist to understand the requirements of each job and how the workstation was being used. During the assessments the duties were discussed in detail and solutions to minimize and eliminate the hazards were explored.  Recommendations were provided following the assessment.

The musculoskeletal hazards present at each workstation are indicated in the chart below:

Greenhouse Packing

The major concerns observed and expressed during the assessment were repetitive reaching and lifting totes on and off the line.  The process requires the worker to lift totes that weigh 20 lbs from a pallet and place them on a conveyor. The worker reaches below knee to above shoulder to remove and stack totes on/off pallets.  Recommendations using multiple levels of the hierarchy of controls were provided: automation, reducing the pallet height, balanced two-person operation, and job rotation.

Pathology Laboratory

The concerns observed were force due to static neck and back postures while using the microscope as well as repetition and contact stress (wrists) bilaterally when manipulating the controls.  Recommendations included a new chair, wider sit/stand workstation, and microscope.

Piano Instructor

In this case, the instructor’s chair was a concern as it could not be adjusted properly to allow for neutral postures and proper support when moving between the piano and computer workstations. Recommendations for a fully adjustable chair were provided.

Receptionist

The receptionist’s workstation created problems for the worker due to force and awkward postures that stem from the workstation setup and placement of the client window.  Temporary recommendations were provided in terms of the positioning and orientation of equipment.  The office will be changing locations in the spring of 2023 and an assessment of the new space has been scheduled.

OHCOW Impact

Recommendations were implemented for each of these workstations, and workers have since contacted the OHCOW ergonomist with positive feedback, indicating that their discomforts have been reduced. A proactive ergonomic consultation is the most effective in musculoskeletal disorder prevention.  The worksite that is moving to a new location has scheduled an assessment to address the workstation and setup requirements once they are relocated.

Background

The claimant worked in a copper refinery for twenty-eight years in different roles, starting in 1970 when he was 35. His jobs included process labourer, chipper and grinder, inspector brakeman, weigher, and in a tank room. When he was diagnosed with lung cancer he claimed it as an occupational disease,  and the claim was denied. His 40 year history of smoking was a factor in the decision, and the fact that his exposure levels did not meet the threshold to substantiate the claim. His specific jobs at the refinery were not considered high risk for increased levels of exposure. He passed away before his claim had been decided by the Board and the Estate continued with the claim.

Intervention

Exposures and risks of lung cancer at the copper refinery were referenced in a peer reviewed study, stating the Polycyclic Aromatic Hydrocarbons (PAHs) were possible causes of lung cancer mortality among nickel/copper smelter and refinery workers. The contracted OHCOW physician concluded that the claimant’s occupational exposures “appear to have made a material contribution to his development of Squamous Cell Carcinoma.” Although his official title was not an “arc furnace operator,” he did work in the arc furnace area; therefore his exposure to carcinogens should be recognized. To further understand the working environment, OHCOW conducted an “intake clinic” in 2018 with retired co-workers who were working in the copper refinery from the early 1960s to early 2000s. The investigation found that all copper refinery workers were exposed to a number of confirmed carcinogens, and that the job title of the worker may not fully represent the extent of their exposures.

After conducting statistical analysis of airborne contaminants throughout various areas, the hygienists were able to confirm the contaminants were distributed evenly throughout the entire plant. They showed that all occupants had an elevated level of risk from being exposed to a combination of airborne contaminants known to cause lung cancer (IARC Group 1) regardless of job title, thus providing a confirmed link between exposures to these Group 1 carcinogens with an increased risk of lung cancer.

OHCOW Impact

WSIAT agreed with the OHCOW report showing evidence that the claimant’s occupational exposures significantly contributed to the onset of his lung cancer, and his Estate was therefore entitled to benefits for the worker’s disease. Significant weight was placed on OHCOW reports and conclusion of the claimant’s indirect exposure to various other lung cancer causing agents. This case indirectly strengthened the power of mixed exposures to various different contaminants and their additive/synergistic effects to the disease outcome. It further strengthens the work-relatedness of exposure to asbestos, and other cancer causing agents in the workplace, by noting that a claimant with a history of smoking could not be denied benefits for lung cancer when there is evidence that the occupational exposures made a material contribution to the onset of disease, then the worker will be entitled to receive benefits for that disease.

Background

The worker was referred to OHCOW by their union after a diagnosis of bilateral Carpal Tunnel Syndrome (CTS) developed during their employment as a Heavy Equipment Operator (HEO). He was employed at six different jobs over a 23 year period (1996-2019), 45 to 60 per week operating excavators, loaders, and a timber material handler. Symptoms of CTS had appeared in 2008 but the worker did not seek medical attention until 2018 when the symptoms began to affect his daily routine and ability to perform his duties.

The claim was originally denied by WSIB that claimed his job included manipulating joysticks (that controlled the movement of the trucks), which is considered low risk for CTS. No sustained forceful pressure, vibration, strong gripping or awkward hand position was present.

Intervention/Approach

The OHCOW ergonomist reviewed the worker’s WSIB file – including medical and work history – and interviewed the worker.  When the worker remarked that the interview had been far more detailed than that with WSIB, the Ergonomist pointed out that it was necessary to look at a person’s entire occupational history and not just current job duties, as musculoskeletal disorders can take years to develop.

The Ergonomist was able to obtain physical demands analysis/description (PDA/PDDs) and combined and weighed them by duration of employment across the workers 23-year career.  The analysis focussed on known risk factors for the development of CTS such as gripping, awkward postures, and low frequency vibration.

The Ergonomist also investigated the timber material handler, the equipment the worker used for the last 7 years.  The  joystick controls not only control the boom arm but were also designed to steer, rotate the cab/boom, raise and lower the boom, opening and closing the claw, stabilizer control, slewing gear brake operation, horn operation, and cab elevation. The hand and wrist would be in constant use while in operation. Awkward wrist postures would have occurred because of the angle of the joysticks.  This also confirms the finding from the PDA/PDDS which had 83.5% of the day spent in wrist flexion and pronation.

OHCOW Impact

Utilizing the information from the worker, the PDA/PDDs, equipment design specifications, and relevant literature, the Ergonomist was able to conclude that [the worker] was indeed subjected to "sustained and prolonged awkward postures of the wrist, high internal forces to sustain holding such positions and muscle fatigue, vibration, and excessive grip force" which are all well documented risk factors for the development of CTS.

Moving Forward

An appeals decision has yet to be rendered by WSIB.

Background

The claimant had been diagnosed with gastro-intestinal (GI) cancer. As a mining process plant operator with continuous and repetitive exposures to asbestos based on exposure estimates, he considered his cancer to be caused by his work environment. The WSIB Appeals Resolution Officer denied the WSIB Claim stating, “the worker’s exposure to asbestos while employed with the employer was not a significant factor in the development of his rectal cancer”.

Intervention/Approach

The OHCOW occupational hygiene retrospective exposure review (RER) challenged the WSIB resolution officer who denied the claim. The report demonstrated a likelihood that the claimant's exposure routinely, continuously, and repetitively exceeded the current TWA Limit as well as exceeding the Ceiling Excursion Limits.

Epidemiological evidence has confirmed an increased risk for three GI cancers, namely esophageal, stomach and colorectal with asbestos exposure.  The most up to date literature review demonstrated an increased risk for the 3 GI cancers from “any exposure” versus non exposed. The review found “more consistent evidence” for all 3 GI cancers.

Exposure estimates demonstrated that a mining processing plant operator’s exposure to asbestos provided a clear and adequate history of asbestos exposure, that was both continuous and repetitive. This successful WSIAT decision, along with systematic literature further opens the door to both retrospective and ongoing exposure reviews.

OHCOW Impact

Using this successful case accepted by WSIAT, coupled with the recent systematic literature review (Demers et al. 2023), opens the doors for many other claims from workers from non asbestos industries to claim compensation. It further highlights the importance, of adequately managing and controlling exposure, where there is legacy asbestos containing material to negate future claims.

Background

The worker was employed for 38 years as an Underground Redevelopment Mining Heavy Duty Vehicle Mechanic.  His exposure occurred during the Traditional (where diesel was the dirtiest and unregulated before 1998) and Transitional Diesel Engine Exhaust periods. He was diagnosed with Non-Hodgkins Lymphoma (NHL), but his claim for restitution for a work-related illness was denied.

Intervention/Approach

OHCOW reviewed the inhalation exposure to diesel engine exhaust. The substance benzene was present in solvents and  diesel fuel as well as diesel engine exhaust. Both the inhalation and the dermal exposure pathways were examined. A WSIB Hygiene report was submitted however they did not characterize the dermal exposure pathways for the patient.

OHCOW Impact

This was a unique case.  Firstly, the claimant worked with older pre 2007 Traditional Diesel Engines (TDE) which are typically "heavier polluters" emitting relatively higher levels of diesel particulate matter (DPM), much more than modern diesel engines with stringent emission controls. Secondly, this was while reworking older mines (mothballing) where it is likely that the ventilation would have been suboptimal, which would have exacerbated his exposure. Older "traditional" (pre 2007) engines have still been in service without after-treatment controls (such as diesel particulate filters (DPF)) combined with poor ventilation would have resulted in elevated exposures.