Histological changes in the bronchi of the adult Wistar rat following exposure to cement dust

Abstract

Cement dust is a harmful air pollutant. Previous research has linked cement dust to respiratory disease, but its effects on bronchi are poorly understood. The present study examined the impact of cement dust on body weight and bronchial function in Wistar rats. Twenty four Wistar rats between250g 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 between them and previous weights were noted. After 28 days, animals were euthanized and bronchiwere collected for histology. Body weight significantly increased (P<0.05) in all groups. The control group had the highest  eight gain compared to the exposed groups. The histological sections of the bronchi of rats in Group A revealed normal bronchi. There were observable histological variations in the bronchial architecture of the exposed rats (Group B-D) which include mucosal ulceration, mucosal infiltrates of inflammatory cells, activated lymphoid follicles and luminal haemorrhage. Histological findings are consistent with usual histological features in bronchiectasis. Cement dust had histomorphological effects on the bronchiwhich are capable of compromising the health of the research animals.