A University of California Los Angeles (UCLA) study of big tobacco intercompany documents released in a 1998 legal settlement — the Tobacco Master Settlement Agreement — shows that tobacco companies tried to keep information discovered in 1959 about radioactive substances in their products quiet for decades.
“The documents show that the industry was well aware of the presence of a radioactive substance in tobacco as early as 1959,” the authors write. “Furthermore, the industry was not only cognizant of the potential ‘cancerous growth’ in the lungs of regular smokers, but also did quantitative radiobiological calculations to estimate the long-term lung radiation absorption dose of ionizing alpha particles emitted from cigarette smoke.”
The study says that tobacco company research identified the radioactive substance as polonium-210 in 1969. The isotope can be found in all foreign and domestic cigarette brands as a byproduct of tobacco crop development.
The tobacco industry has not only been aware of the isotope since 1959, but has also known of two processes by which it can be eliminated, says the study. One technique, developed in 1980 and called acid washing, was found to be highly effective in removing the isotope from tobacco plants, where it forms a water-insoluble complex with the sticky, hair-like structures called trichomes that cover the leaves. The tobacco industry allegedly shunned the process because it was also shown to have an impact on the levels of the content of nicotine in tobacco, the drug which keeps smokers hooked.
“The industry was concerned that the acid media would ionize the nicotine, making it more difficult to be absorbed into the brains of smokers and depriving them of that instant nicotine rush that fuels their addiction,” said one researcher.
The study comes out just two years after 2009 passage of the Family Smoking Prevention and Tobacco Control Act, which grants the U.S. Food and Drug Administration broad authority to regulate and remove harmful substances besides nicotine from tobacco products. The study’s authors hope that their research will be taken into account by the FDA as it attempts to regulate tobacco safety.