Eye Pollution

Particulate matter exposure is one of the strongest predictors of mortality among air pollutants. To date, pollutants have been implicated in brain conditions, such as Alzheimer’s, Parkinson’s, and strokes, and now they have been linked to irreversible sight loss. A long-term study (1) found that people in polluted areas were at least 8 percent more likely to suffer from age-related macular degeneration (AMD) – the leading cause of irreversible blindness among people over 50 in high-income countries. 

UCL researchers assessed data from 115,954 UK Biobank study participants between the ages of 40 and 69. The participants, who had no eye conditions at the beginning of the study, were asked to report any formal diagnosis of AMD by a doctor. Just under half of participants were assessed by OCT for structural changes in the thickness and/or numbers of light receptors in the retina – both indicative of AMD. 

The team then compared changes in retinal structure against the annual average air pollution levels of participants’ home addresses. After accounting for potentially influential factors, such as underlying health conditions and lifestyle, they found that people in areas with higher levels of fine particulate matter pollution were more likely to report having AMD. Higher exposure to air pollution was also associated with structural features of AMD, indicating that higher levels of air pollution may cause the cells to be more vulnerable to adverse changes, increasing the risk of AMD. Although the authors could not confirm why AMD is affected by pollutants, research suggests that oxidative stress or inflammation may play a role.

“Here we have identified yet another health risk posed by air pollution, strengthening the evidence that improving the air we breathe should be a key public health priority” said lead author Paul Foster, Professor at the UCL Institute of Ophthalmology (2). “Even relatively low exposure to air pollution appears to impact the risk of AMD, suggesting that air pollution is an important modifiable risk factor affecting risk of eye disease for a very large number of people.”