Pulmonary anthracosis in Dhaka Zoo collections - a public health forecasting for city dwellers

Abstract

Anthracosis is a lung disease associated with inhalation of coal dust and carbon particles. We tested for anthracosis symptoms in 36 captive animals in the Dhaka Zoo. Necropsy revealed 27 out of 36 animals to be affected by pulmonary anthracosis. The changes included minute black spots to blackish discoloration and congestion in the lungs. In some cases, the lungs showed yellow-white caseous nodules of variable size. Lung tissue samples were stored in 10% neutral buffered formalin. Fixed tissues were processed and stained as per standard procedure. Histopathological examination revealed deposition of carbon particles of varying sizes, shapes and amounts in the lung parenchyma, in the alveolar septa and in and around granuloma. Reptiles, newly arrived animals and animals less than one year of age were found free from anthracosis. This report confirms the occurrence of anthracosis in captive animals at Dhaka zoo indicating severe air pollution in and around the zoo.