The bystander effect in experimental systems and compatibility with radon-induced lung cancer in humans.

Abstract

Bystander effects following exposure to alpha-particles have been observed in C3H 10T1/2 cells and in other experimental systems, and imply that linearly extrapolating low-dose risks from high-dose data might materially underestimate risk. The ratio of lung cancer risk among persons exposed to low and high doses of radon daughters is 2.4-4.0, with an upper 95% confidence limit (CL) of about 14. Assuming that the bystander effect observed in the C3H 10T 1/2 data applies to human lung cells in vivo, the epidemiological data imply that the number of neighbouring cells that can contribute to the bystander effect is between 0 and 1, with an upper 95% CL of about 7. As a consequence, the bystander effect observed in the C3H 10T1/2 system probably does not play a large part in the process of radon-induced lung carcinogenesis in humans. Other experimental data relating to the bystander effect after alpha-particle exposure are surveyed; some of these data are more compatible with the epidemiological data.

• Authors: M P Little, R Wakeford
• Journal: Journal of radiological protection : official journal of the Society for Radiological Protection (J Radiol Prot) Vol. 22 Issue 3A Pg. A27-31 (Sep 2002) ISSN: 0952-4746 [Print] England
• PMID: 12400943 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Air Pollutants
• Air Pollutants, Occupational
• Air Pollutants, Radioactive
• Radon

Topics

• Air Pollutants (adverse effects)
• Air Pollutants, Occupational (adverse effects)
• Air Pollutants, Radioactive (adverse effects)
• Animals
• Bystander Effect
• Cell Line, Transformed
• Cell Transformation, Neoplastic (radiation effects)
• Humans
• Lung Neoplasms (etiology, physiopathology)
• Mice
• Neoplasms, Radiation-Induced (etiology, physiopathology)
• Radiation Dosage
• Radon (adverse effects)
• Risk