This picture shows a worker spreading asbestos on the boiler of a locomotive. It was taken in 1942. It is amazing how many old pictures you find like this one, showing someone working with asbestos, without any breathing protection. Also notice that his hat and coveralls are covered with asbestos. It was in the 1940's that people really began to suspect that there were health hazards associated with asbestos exposure. It was found to cause both asbestosis, a form of inflammation of the lungs, and Mesothelioma. Mesothelioma is a form of cancer that can almost always be associated with exposure to asbestos. It affects the linings of organs, especially the lungs. It has been found that even the family members of those working in the asbestos industry can be susceptible to these diseases.
It really makes you wonder what types of things they might tell you are safe today, and then you find out years later they were dangerous. When I was a teenager, I worked in a cotton gin for $1 an hour. While there was not any asbestos there (that I know of), there was a large amount of fine cotton fibers, which I have heard can be a concern. I only worked there one summer, so hopefully it will not be an issue. I do believe, though, that overall, worker safety has greatly improved in the United States. I think the greatest work danger these days is due to stress to get too much done in too little time.