According to recent studies, air pollution is one of the causes of dry eye syndrome. The presence of some elements in the air we breathe can have deleterious effects, especially those particles whose size is small enough to penetrate the respiratory system. Particles with a diameter of less than 2.5 µm (PM2.5), which make up the respirable fraction of particulate matter, contain elements derived from diesel engine combustion or carbon particles from photochemical processes that can cause damage to the visual apparatus.
Dry eye syndrome is a condition whose prevalence is increasing. Several heterogeneous factors, not always related to each other, contribute to this increase: from prolonged and constant use of device electronic to pollutants in the air.
Recently, the effects of environmental pollution on human health have attracted the attention of many researchers who have begun to analyse its effects. The presence of PM2.5for example, is not only harmful to the lungs, but has deleterious effects on the cardiovascular and visual systems. It is not difficult to imagine, in fact, that the presence of these elements in the air damages the eyes, which are the organ most exposed and in direct contact with the outside world. There is no lack of scientific evidence showing that the components of the PM2.5 cause certain eye disorders, the most frequent symptoms of which are itching eyes, foreign body sensation, tearing and burning, as well as clinical signs such as oedema or eyelid swelling.
PM2.5 and dry eye syndrome
The first study to evaluate the effects that the PM2.5 has in promoting the onset of dry eye syndrome was published in the journal Scientific Reports-Nature recently. The study data show that the structure and stability of the tear film are significantly altered in mice treated with PM2.5 . In fact, the microvilli of the corneal epithelium had undergone a reduction in numbers and an alteration in their structure, which appeared disorganised after treatment. In addition, the conjunctival calyciform cells, which normally regulate the secretion of mucin, a substance essential for tear stability, had suffered a marked reduction.
The administration of PM2.5 therefore, was found to induce ocular surface changes in mice similar to those in the human dry eye and, therefore, the study data as a whole support the hypothesis that theair pollution causes negative effects on human health in general and on that of our eyes in particular.
Source
Tan.G et al. Air pollutant particulate matter 2.5 induces dry eye syndrome in mice. Scientific ReporTs | (2018) 8:17828.
Dr. Carmelo Chines
Direttore responsabile
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