USA– Colorado researchers have discovered that an acidic gas found in cigarette smoke also is a component of smoke from wildfires.
The discovery was confirmed last fall when a wildfire west of Boulder brought smoke to researchers working nearby in a National Oceanic and Atmospheric Administration lab.
They had already measured isocyanic acid in tobacco smoke and highly polluted cities such as Los Angeles. But as thickening smoke from the advancing Fourmile Canyon wildfire which scorched more than 6,000 acres and destroyed 169 buildings settled over their lab in south Boulder in September, NOAA and University of Colorado scientists began switching on the spectrometers they had designed to analyze air.
The results proved especially troubling for those who had assumed wildfire smoke might be less harmful than smoke from cigarettes, said scientist Joost de Gouw, co-author of a study published Monday in the Proceedings of the National Academy of Sciences.
“We previously didn’t know that fires were such a large source of this compound,” he said.
Prior research indicates isocyanic acid can hurt people in concentrations of 1 part per billion volume or higher. In Boulder, concentrations reached only 0.2 ppbv, but mountain-dwellers probably inhaled more, said Jim Roberts, a NOAA research chemist on the project.
“We’re probably looking at more frequent forest fires because of a warmer, drier climate and dead trees sitting in the forests,” Roberts said. “That means more exposure.”
Once inhaled, isocyanic acid forms cyanate molecules that can dissolve in the bloodstream. These can contribute to human health problems, including cardiovascular disease, cataracts and arthritis.
More research into health effects is needed, de Gouw said. “We know smoke is bad for you. What this study showed is a new mechanism by which it is harmful to you.”
Beyond Colorado’s burgeoning settlement in mountain wildfire zones, more than 1 billion residents of low-income countries rely on open wood fires for cooking, often in poorly ventilated homes.