Subacute pulmonary toxicity of copper indium gallium diselenide following intratracheal instillations into the lungs of rats

Objectives: The aim of this study was to clarify the pulmonary toxicity of copper indium gallium diselenide (CIGS) solar cells on 62 8-wk-old rats. Methods: Male Wistar rats were given 0.5, 5 or 50 mg/kg of CIGS particles, intratracheally, 3 times for a week. Control rats were given vehicle, distilled water, only. These rats were euthanized 0, 1 or 3 wk after the final instillation serially, and toxicological effects were determined. Results: None of the CIGS-treated groups exhibited suppression of body weight gain compared with the control group. The relative lung weight in the CIGS 5 mg/kg-treated and 50 mg/kg-treated groups were significantly increased compared with that in the control group throughout the observation period. Although serum copper (Cu) and selenium (Se) concentrations were not affected by instillations of CIGS particles, the indium (In) levels increased with the passage of time in the CIGS 5 mg/kg-treated and 50 mg/kg-treated groups. However, the serum gallium (Ga) levels decreased in the CIGS 50 mg/kg-treated group from 0 to 3 wk. The content of each metal in the lung increased depending on the dose instilled and was constant during observation periods. Histopathologically, foci of slight to severe pulmonary inflammatory response and exudation were present among all the CIGS-treated groups, and the severity of these lesions worsened with the passage of time. Conclusion: The present results clearly demon-strate that CIGS particles caused subacute pulmonary toxicity and that dissolution of CIGS particles in the lung was considerably slow when repeated intratracheal instillations were given to rats.