A new study on the health risks of asbestos exposure to seamen working on commercial ships was recently published in the medical journal Inhalation Toxicology. According to the results of the study, asbestos exposure is believed to have occurred due to repairs to the ships and maintenance tasks throughout the time that seamen worked on these non-military vessels.
The study measured airborne asbestos on merchant ships and the resulting health of its merchants over time. Previous studies on the communications and actions of U.S. organizations concerning maritime health and safety were also taken into consideration.
According to the study, data from before 1970 was mostly based on studies of workers in manufacturing, milling, and mining industries that used asbestos. This is because in many cases, the health risks of asbestos exposure to merchant seamen were largely unknown until the 1970s and 1980s.
Although asbestos air levels were found to be below 1 f/cc for most repair and maintenance work, a few pleural abnormalities were discovered in some U.S. seamen. This raised a red flag for the U.S. government and several industry and labor organizations.
In the 1990s, increases in lung cancer and mesothelioma were found in studies of seamen, which led researchers to believe there was a causal link between asbestos exposure on ships for seamen and these lung diseases.
In 2008, a similar study was published on asbestos in maritime shipping vessels because the same level of review given to Navy sailors was not being given to merchant seamen, despite the fact that both groups have historically used many tons of asbestos to build and repair their vessels.
Asbestos was often used in sea vessels because it was an effective insulator to prevent condensation, reduce the ventilation needed to cool spaces, allow machinery to operate with decreased heat loss, and prevent workers from needing to come into contact with hot components.
Historical industrial hygiene data from maritime shipping vessels between 1978 and 1992 was used in the 2008 study, including oil tankers and cargo vessels that were docked and/or at sea. Although many samples were collected from suspected asbestos-containing materials, they were not taken during times when interaction with the materials would’ve occurred.
Results of the study showed asbestos levels were consistently below U.S. occupational standards and almost always below the current expectations of 0.1 f/cc. So the mere presence of undisturbed asbestos did not significantly increase exposure.
In 2003, a National Health Institute study concluded mesothelioma cancer should be considered an occupational disease for merchant mariners and that occupational asbestos exposure contributes to their increased cancer mortality.