| One question that has puzzled many researches is | | | | presents a prospect of limited effectiveness. With |
| whether or not there is a definitive threshold regarding | | | | asbestos, as with any carcinogen, no threshold is |
| levels of asbestos exposure and disease | | | | known below which no health effect may be manifest. |
| development. One interesting study that explores this | | | | At best, we have only limited dose-response |
| issue is called, âAsbestos - the TLV | | | | information at levels much above those of practical |
| approachâ - Ann N Y Acad Sci. | | | | concern. In the case of asbestos, current exposures |
| 1976;271:152-69. by Nicholson WJ. Here is an excerpt: | | | | can only be described crudely at any level of |
| âAbstract - A review of the control of | | | | exposure, and health effects are only known for past |
| carcinogenic exposures using the TLV approach | | | | high, but ill-defined, exposures. |