Asbestos exposure risk exaggerated, studies suggest

Projected rates of asbestos-linked disease in the U.S. were grossly exaggerated, says the president of the Asbestos Institute of Montreal.

Michel Gratton was responding to the publication of several scientific reports that refute the asbestos risk-estimates on which regulatory action in the U.S. and elsewhere had been based.

Much of the public’s concern about the health risks of asbestos exposure is the result of predictions by U.S. health officials during the 1970s, Gratton says. Studies have now shown, he says, that the fear generated by these reports was unwarranted.

“The Journal of the National Cancer Institute (in its April 15 edition) reported that the huge number of asbestos-related cancer cases once forecast in the U.S. have not materialized, and experts say the dire predictions of the 1970s were overblown,” remarked Gratton.

The estimates purported that industry workers in the 1960s and 1970s exposed to relatively low levels of asbestos fibres would suffer the same fate as those who in the past were exposed to much higher doses. “Clearly this wasn’t the case,” Gratton says.

He notes a study presented at the International Symposium on Epidemiology in Occupational Health in September in Cincinnati by two individuals, Liddell and McDonald, evaluated more than 11,000 chrysotile asbestos miners born between 1891 and 1926.

The study concluded that at exposures of less than 50 fibres per cubic centimetre (f/cc), no excess lung cancers were observed. Thus, at current occupational exposure levels (less than 1 f/cc), any deaths from asbestosis or lung cancer would be extremely unlikely.