Adverse effects attributed to long-term radon inhalation in rats

Area of Science:

• Environmental Health
• Toxicology
• Radiation Biology

Background:

• Radon is a radioactive gas and a known human carcinogen, primarily linked to lung cancer.
• Long-term exposure to radon can induce cellular damage in respiratory tissues and potentially systemic effects.
• Understanding the specific cellular and molecular impacts of radon exposure is crucial for risk assessment and mitigation.

Purpose of the Study:

• To investigate the adverse effects of chronic radon exposure on lung and blood cells in Sprague-Dawley rats.
• To evaluate dose-dependent cellular and molecular changes following radon exposure.
• To explore the potential of peripheral blood mononuclear cells (PBMC) as biomarkers for radon-induced lung damage.

Main Methods:

• Rats were exposed to cumulative radon doses of 66, 111, and 174 Working Level Months (WLM).
• Cellular analysis of bronchoalveolar lavage fluid (BALF) and peripheral blood included total and differential cell counts.
• DNA damage was assessed using single-cell gel electrophoresis (SCGE), and Interleukin-6 (IL-6) mRNA expression was analyzed via RT-PCR.

Main Results:

• Radon exposure led to significant alterations in BALF cell composition, with decreased lymphocytes and increased granulocytes.
• A dose-dependent increase in DNA migration distance was observed in both BALF cells and PBMC.
• A positive correlation was found between DNA damage levels in PBMC and BALF cells.

Conclusions:

• Radon exposure induces significant DNA damage in lung and blood cells in a dose-dependent manner.
• Peripheral blood mononuclear cells (PBMC) exhibit DNA damage patterns similar to lung cells, indicating their potential as non-invasive biomarkers.
• Monitoring DNA damage in PBMC could offer a practical approach for assessing radon-induced lung damage.