If you’re like most animals, you rely on your vision as the main navigation tool guiding you through life. For those who have unfortunately lost their vision, or have reduced visual ability, life can be a struggle, even with coping mechanisms.
There are many causes of vision loss, from heredity to catastrophic incidents like a car or motorcycle accident, but there are many more hidden factors between these two that may come as a surprise to many.
The environment, more specifically harmful environmental substances, can lay claim to many ailments, from heavy metal poisoning and cardiovascular illness, all the way to deafness and blindness. But sometimes the environment is not easily identified as the direct cause of blindness.
A study published in 2016 in the Journal of Diabetes Research identifies external environmental factors to be complicit in blindness, namely substances in the phthalate family, chemicals we come in contact with during our everyday lives, are ingesting in unhealthy quantities, and yet have most likely never heard of.
Phthalates are a type of ester made of phthalic acid used in plastics to give the plastic more flexibility, transparency, durability, and longevity. The issue with these chemicals is that they do not share a covalent bond with the plastic its self, so exposure to heat or organic solvents can release them from the plastic, and in today’s era of just about everything being made of plastic, phthalic acid very commonly leaches into the food we eat from plastic dishes. In fact, most Americans tested by the Centers for Disease Control and Prevention have metabolites of multiple phthalates in their urine.
Researchers noticed an association between phthalate metabolites found in urine and self-reported eye affliction in individuals with diabetes.
Exposure to phthalates has already been associated with type 2 diabetes, but researchers are still trying to figure out the mechanisms of this relationship. In doing so, they noticed that patients with type 2 diabetes who experienced retinopathy also had high levels of phthalates in their urine.
They studied the association of 12 urinary phthalate metabolites with self-reported eye affliction/retinopathy in 1,004 participants with diabetes. Researchers found Self-reported eye affliction/retinopathy had 82% accuracy with Cohen’s kappa, a statistic which measures inter-rater agreement for qualitative (categorical) items.
Scientists found this association between Urinary mono-n-octyl phthalate and eye affliction/retinopathy so profound that they are led to believe there are existing cases of blindness due to type 2 diabetes that have been misclassified, that are actually due to exposure to phthalates.
Another recent study examined the link between urinary environmental chemical concentrations and vitamin D in elderly individuals suffering from vision, hearing, and balance disorders. Researchers aimed to “determine the relationships between urinary environmental chemicals (including heavy metals, environmental bisphenols, pesticides, arsenic, and phthalates) concentrations and vision, hearing, and balance disorders in a national population-based setting.”
We all know that heavy metal poisoning can easily lead to death, but research shows more and more that they can play a major role in debilitating disease, as can other compounds we’re exposed to on a daily basis.
The study found that the compounds cadmium, molybdenum, and tungsten concentrations, all commonly linked to heart disease, can also be associated with vision disorder. Other compounds tested were also linked to hearing disorder, buzzing and hissing in the ears, and ringing in the ears, and still more were newly linked to balance disorders.
These chemicals were easily detected in the urine of participants, making it relatively simple to get checked by a doctor regularly. Yet the true discovery is the continual realization that the substances we’ve deemed to be the cause of one ailment are truly doing more damage to our bodies than previously realized.
It’s been decades since we discontinued using Dichlorodiphenyltrichloroethane (DDT), and the effects of it are still in the American consciousness. In 1962 Rachel Carson wrote about the dangers of DDT to both the environment and to human life, claiming that it caused cancer, sparking the early embers of the now widely popular environmental movement.
But long after abandoning DDT, American farmers have devised new creations to help prevent crop destruction via insect, and these chemicals may not be much better for your health than the blacklisted DDT.
Research has associated pesticide exposure with retinopathy in agricultural workers. Perhaps even more disturbing is that the wives of these agricultural workers also exhibited ocular damage from pesticide exposure, even though they are contacting it second hand.
While farm workers are likely the most affected by pesticide exposure, its reach extends to the supermarket and into your kitchen, with one of the newly observed effects of exposure to common pesticides being damage to the eye.
One study shows that exposure to pesticides via inhalation, ingestion, dermal contact and ocular exposure can all cause damage to the eye. Physical exposure via contact with the eye can lead to absorption in the ocular tissue and potential ocular toxicity.
Researchers tested the tissue inside the eye of animals exposed to pesticides and found Cholinesterase enzymes with evidence of organophosphate-induced inhibition. The effects of pesticides have been observed in various parts of the eye including conjunctiva, cornea, lens, retina and the optic nerve.
Japanese researchers call this disorder Saku disease, an optico-autonomic peripheral neuropathy, has been described in Japan in people living in an area where organophosphates were used, and authorities consider this a serious health concern.
Thankfully, there is renewed focus on fresh, organic produce in America and much of the modern world, but there are still those who cannot necessarily afford to live that lifestyle, or who must work on farms that use pesticides to treat produce, but hopefully regulations can continue to restrict the types and amounts of chemicals that agriculturalists are able to use on the food and products we’re all forced to consume and have exposure to in our daily lives, because the gift of sight is truly a remarkable one.