Abstract:
Background Non-occupational arsenism is largely ascribed to arsenic exposure through arsenic contaminated coal, drinking water, and food. Lung is one of the target organs of arsenic. Lung function indicators can reflect early lung injury, and have great significance in evaluating the grade of lung injury and labor capacity of arsenism patients.
Objective Our aim is to investigate the lung function in patients from a coal-burning type arsenism area in Guizhou Province.
Methods In a coal-burning arsenism area named Yuzhang Village, a total of 216 cases of coalburning type arsenism were diagnosed according to the Standard of Diagnosis for Endemic Arsenism (WS/T 211-2015), including 56 mild, 81 moderate, and 79 severe cases. In a non-coalburning arsenism area, 79 healthy residents indicated by physical exams were selected as control group who had similar living habits, but no high-arsenic coal-burning history nor inheritance and family history of cancer. Lung function was evaluated using spirometer, and the indicators included forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1). FEV1/FVC lower than 92% of the predicted value was used as a sensitive indicator of obstructive ventilatory disorder.
Results There was no significant difference in age and sex between designed groups. The rates of pulmonary ventilation disorder in the mild, moderate, and severe coal-burning type arsenism groups were 30.4%, 43.2%, and 45.6%, respectively, which were higher than 7.6% in the control group (P < 0.05). The rates of obstructive ventilatory disorder in the mild, moderate, and severe groups were 26.8%, 30.9%, and 31.6%, respectively, which were all higher than 6.3% in the control group, and increased with the aggravation of coal-burning type arsenism (χtrend2=14.51, P < 0.05). The rates of restrictive and mixed ventilatory disorder in the mild, moderate, and severe groups were 3.6%, 12.3%, and 13.9%, respectively, which were all higher than 1.3% in the control group, and also increased with the aggravation of coal-burning type arsenism (χtrend2=11.08, P < 0.05). Compared with the control group, the levels of FVC, FEV1, FVC%, FEV1/FVC, MEF75%, MEF50%, and MEF25% in the three arsenism groups were all reduced (P < 0.05). The FEV1/FVC and MEF75% in the severe group were lower than those in the mild group (P < 0.05).
Conclusion Both large and small airways of the patients with coal-burning type arsenism are impaired, manifested as obstructive ventilatory disorder, and the decline of lung function may be associated with arsenic exposure.