Effects of Coal Dust Contiguity on Xerophthalmia Development

To study the occurrence of ocular surface diseases on coal miners working under wells and to investigate the relation between xerophthalmia occurrence and coal dust contiguity.To observe the influence of coal dust to ocular surface by using Schirmer to detect lacrimal gland secreting function, and breakup time of tear film (BUT) to evaluate the stability of lacrimal film and the quantity of lysozyme in lacrimal fluid.These values were lower for underground coal miners than other workers not contacting coal dust, and showed negative correlation to period of their services.Conditions in coal miners were worse than that of other workers. Coal dust exposure plays an important role in the development of dry eye.