Histological changes in the bronchioles and alveoli of the adult Wistar rat following exposure to cement dust

Abstract

Background: Cement dust is a harmful air pollutant. Previous research has linked cement dust to respiratory tract disease, but its effects on bronchioles and alveoli are not well understood. The present study assessed lung damage in Wistar rats exposed to cement dust

Objectives: To investigate the effects of cement dust exposure on the weight and in the bronchioles and alveoli of Wistar rats.

Methods: Twenty-four Wistar rats weighing between 250g and 280g were divided into 4 groups of 6 rats each. Group A rats were placed in a cement dust free chamber while Group B - D animals were exposed to cement dust dispersed from 5g, 10g and 20g of cement, respectively via dust distributor glass-chamber of dimensions 32.5 cm3 × 32.5 cm3 × 16.5 cm3 for 1 hour daily for 30 days. The weights of the rats were taken weekly and the difference noted. After 28 days, the Wistar rats were euthanized and lungs collected for histology.

Results: The histological sections of the lungs of rats in Group A revealed normal alveoli and bronchioles. There were observable histological variations in the lung architecture of the exposed rats (Groups B, C and D) which include activated lymphoid follicles, bronchioar ulceration, patchy alveolar collapse and vascular ulceration. Histological findings are consistent with usual histological features in pneumonitis.

Conclusion: Cement dust had histomorphological effects on the bronchiolar and alveolar walls, which are capable of compromising the health of the research animals.