- Cancer (bladder)
- Evidence (epidemiological)
- Exposure (diesel fumes)
- Transportation industry (bus driver)
The worker was a school and transit bus driver from 1982 to 2004. She was diagnosed with bladder cancer in 2004. The worker appealed a decision of the Appeals Resolution Officer denying entitlement for the bladder cancer.From 1982 to 1987, the worker drove a school bus with a gasoline engine, so that there was minimal exposure to diesel exhaust. From 1987 to 1990, she worked as a school bus driver and a transit bus driver. The transit buses had diesel engines. Thus, there was some diesel exhaust exposure. From 1990 to 1998, she worked full-time as a transit bus driver. After 1998, she worked performed office duties at the garage, so that exposure was reduced.Epidemiological studies that have considered bladder cancer in bus drivers generally show a relative risk significantly lower than 2.0, particularly when adjusted for smoking. Smoking was a proven risk factor for bladder cancer. The worker had stopped smoking 17 years prior to diagnosis but a Tribunal medical assessor was of the opinion that the relative risk for ex-smokers remains at around 2.0. The latency in this case was also not suggestive of a link between occupational exposure and the bladder cancer. Exposure started in 1987. Diagnosis was 17 years later, in 2004, which was below the 20-year latency for solid tumours. The worker's bus driving employment did not place her in a high exposure category.The Panel also noted that the epidemiological evidence regarding truck drivers and bladder cancer is somewhat stronger than for bus drivers, due to placement of the exhaust pipe under the engine hood in front of the driver's seat on long-haul trucks as opposed to the back of buses about 35 feet away from the driver's seat.The worker did not have entitlement for the bladder cancer. The appeal was dismissed.