Is cancer in Israeli professional divers exposed to polluted waters an occupational disease?

Because there is some contamination of practically every body of water, risk analysis is important to determine diving exposure standards to pollutants, including requirements for protective equipment. In the following study we attempt to determine the increased risk of cancer in Israeli Naval divers exposed to pollutants in the Kishon River system. We calculated two risks, one using maximally recorded levels of pollutants outside the diving areas (worst-case scenario), and the other using maximally recorded levels in the actual diving areas. For both calculations we used conservative assumptions for exposure (2500 exposure hours with 50% of body covered with sediment), and a synergistic risk model. We considered all chemicals that were carcinogenic by inhalation also to be carcinogenic by oral and dermal absorption. The relative risk was 1.13 for the worst-case scenario, and 1.004 for exposures in actual diving areas. We conclude that it is unlikely that exposure to the polluted Kishon River waters can cause a detectable increase in cancer risk in Israeli Navy divers. This study has implications for professional divers exposed to polluted waters.