The Relationship Between Smoking and Lung Cancer Death Rates Among Asbestos Workers

The UK Asbestos Survey

According to the Great Britain Asbestos Survey, funded by the UK Health and Safety Executive (HSE), both smoking and asbestos work are independent risk factors that increase lung cancer death rates. The study found that the harmful effects become much more severe when asbestos workers also smoke.

This survey studied asbestos workers who received medical checkups between 1971 and 2005 (a period of 34 years). Out of a total of 98,912 workers, 1,878 people (12%) died from lung cancer.

Most of the people in the study had already been exposed to asbestos before the ALR (Asbestos Licensing Regulations, 1983) came into force. These regulations require regular health checks for asbestos workers. In addition,

• About 40% were first exposed to asbestos at work between the ages of 20 and 29

• 63% were exposed to asbestos for less than 10 years

• 50% were current smokers at the time of their last medical checkup

• 24% had never smoked

 

Study Results

The results showed that asbestos workers had a higher lung cancer death rate than the national average. Among them, asbestos workers who had never smoked showed the lowest Standardized Mortality Ratio (SMR), while current smokers had the highest SMR.

Even after adjusting for smoking, asbestos workers still had a higher lung cancer death rate than the general population. When an asbestos worker who smokes dies from lung cancer, the causes can be explained as follows:

• Asbestos alone: 3%

• Smoking alone: 66%

• Interaction between asbestos and smoking: 28%

 

Increased Risk

Both smoking and asbestos exposure are harmful factors that contribute to lung cancer, so it is expected that having both increases the risk of death from the disease. However, the UK Health and Safety Executive (HSE) stated that it is more accurate to say that the risks do not simply add up (additive), but instead increase together in a multiplying way (multiplicative).

The HSE also reported that even smokers can reduce their risk of lung cancer death if they quit smoking. After 40 years of not smoking, the risk of lung cancer becomes almost the same as that of people who have never smoked.