Final answer:
Bruce Hsieh may be at a higher risk of Multiple Chemical Sensitivity (MCS) from his job servicing office printers and copiers due to exposure to VOCs and particulate matter.
Step-by-step explanation:
Bruce Hsieh, who services office printers and copiers in downtown Vancouver, might be at higher risk of acquiring an occupational disease than his brother, who works as a zookeeper. The occupational disease that Bruce may be at a higher risk of is Multiple Chemical Sensitivity (MCS). This condition arises due to prolonged exposure to the volatile organic compounds (VOCs) and fine particulate matter released by printers and copiers. MCS is characterized by a wide array of symptoms, including headaches, fatigue, and respiratory problems, which occur when an individual is exposed to various environmental chemicals, even at low levels.