Common asbestos lung disease does not increase risk of lung cancer
A new study led by Curtin University has found that people who are diagnosed with the most common form of asbestos-related lung disease are not at an increased risk of developing lung cancer later in life.
The research, published in the American Journal of Respiratory and Critical Care Medicine, examined the relationship between asbestos-related pleural plaques and an increased risk of lung cancer in more than 4,200 workers exposed to asbestos from mixed occupations, mostly tradesmen, and the Wittenoom crocidolite mine and township in the Pilbara, Western Australia.
Lead author Professor Fraser Brims, from the Curtin Medical School and Sir Charles Gairdner Hospital in Perth, said the relationship between asbestos-related pleural plaques and the risk of lung cancer was not well understood. The study examined two large asbestos-exposed populations with different types and intensity of asbestos exposure and found that the presence of pleural plaques did not increase the risk of lung cancer, after adjusting for smoking history, asbestosis and asbestos exposure.
Professor Brims said, "We found that it was the level of asbestos and tobacco exposure, and not the plaque that raises the risk of lung cancer. Our findings demonstrate that pleural plaques should not be used as an independent marker to assess the risk of lung cancer, as not everyone exposed to asbestos develops pleural plaques.”
Read more: Curtain University Media release; Brims, F, et al: Pleural Plaques and the Risk of Lung Cancer in Asbestos-exposed Subjects [Abstract], American Journal of Respiratory and Critical Care Medicine
Firefighters, first responders need closer cardiac monitoring
A US electrocardiographic study of firefighters during a live firefighting drill suggests there is a need for closer monitoring of workers who perform activities with high levels of cardiac strain.
Researchers from Skidmore College's First Responder Health and Safety Laboratory and the National Institute of Occupational Safety and Health have found that firefighting exposes workers to cardiac stressors such as dehydration, hyperthermia, increased physical demands, psychological stimulation, and exposure to particulate matter and other combustion products.
They recorded ECG readings from 32 firefighters for 12 hours following a live-firefighting drill, and found 20 per cent of the firefighters showed ventricular arrhythmia and 16 per cent had changes indicative of myocardial ischemia. Both conditions are associated with sudden cardiac events and were not detected in a non-firefighting control group.
These new findings echo those of Canadian researchers, who say rescue exercises and emergency drills should be carefully monitored and include a recovery plan. In the Canadian study, researchers from the Laurentian University Centre for Research in Occupational Safety and Health monitored workers while they participated in a mine rescue simulation competition, and found nearly half had dangerously high heart rates and more than half had mean core body temperatures well above normal. This highlighted the need for rest and hydration protocols, comprehensive heat exposure plans and back-up teams to reduce mission time.
While paramedics are often on hand during drills, closer attention should be given to all participants immediately after an event and they should be tested for heat strain and monitored for at least one hour, the research team said.
In the US study, the researchers say their ECG findings could reflect heart stress from strenuous or prolonged exercise that is "transient and benign", like that experienced by endurance athletes, and does not pose a risk of sudden cardiac events, but given the evidence of a much higher risk of sudden cardiac events among firefighters after firefighting, this is unlikely.
Read more: Denise Smith, et al, Electrocardiographic Responses Following Live-Fire Firefighting Drills. [Full text] Journal of Occupational and Environmental Medicine, Volume 61, Issue 12, December 2019. Source: OHSAlert
