Purpose:
This study evaluates the impact of the sugar cane burning emissions on the quantity and quality of mucus present on the ocular surface of sugar cane workers and healthy controls.
Methods:
Seventeen sugar cane workers and nineteen volunteers from the rural city of Mendonça, Sao Paulo, Brazil, were evaluated. Impression cytology specimens of inferior bulbar conjunctiva were collected and PAS and Alcian Blue (AB) stainings were performed during the burning and non-burning periods. The number of cells/area (mm2) was counted using Image Pro Plus 4.5.
Results:
We observed that the PAS, the AB and the total density of cells on impression cytology samples of inferior bulbar conjunctiva of sugar cane workers were significantly lower during the burning than the non-burning period (p<0.05). There was a significant decrease of the total amount of cells/area on the sugar cane workers when compared with the control group during the burning period (p=0,002). PAS positive cells/area in controls during the burning period was higher than the non-burning period (Figure 1). In general, the number of cells AB positive/area on impression cytology samples of sugar cane workers was higher than the number of PAS positive cells.
Conclusions:
The present findings suggest that air pollutants derived from seasonal episodes of high levels of air pollution, generated by sugar cane burning, may cause toxic effects on the mucosal layer of ocular surface and induce alterations in the human conjunctival epithelium. It also suggests an alteration on the quality of the produced mucus. In conclusion, we reinforce the importance of further investigations for a better understanding of the mechanisms of particle-induced injury and its consequences on the ocular surface.
Keywords: ocular irritants • pathobiology • conjunctiva