Onions - As onions are sliced, cells are broken, allowing enzymes called alliinases to break down sulfides and generate sulfenic acids (amino acid sulfoxides). Sulphenic acids are unstable and decompose into a volatile gas called syn-propanethial-S-oxide. The gas diffuses through the air and eventually reaches the eye, where it reacts with the water to form a diluted solution of sulfuric acid. This acid irritates the nerve endings in the eye, making them sting. Tear glands produce tears to dilute and flush out the irritant.
Salt/Saltwater- Although tears contain salt, they also cotain a complex system of other dissolved substances, and the influx of salt upsets this balance and requires cleansing.
Citrus - Citrus is acidic, and burns because getting lemon, lime or any other citrus juice in your eye is the same as getting acid in your eye
Soap -Soap is a base; the opposite of an acid. Bases pull molecules off of other molecules, soap does this specifically for fat molecules. This action causes a burning sensation when soap comes in contact with fat molecules near the surface of the eye. Tears, which are naturally acidic, counteract the stinging caused by soap.
Peppers -The ingredient in peppers that creates a stinging sensation is called Capsaicin. Capsaicin selectively binds to a protein known as TRPV1 that resides on the membranes of pain and heat sensing neurons, causing a burning sensation.
Contact Lens Solutions -A contact lens solution may increase eye irritation/burning sensation if one is allergic to one of the ingredients within the solution. CL solutions usually contain preservatives and while some preservatives may not cause irritation, others may irritate you.
Chlorine -if the concentration of chlorine is too high in a pool, the excess chlorine can bind to water molecules in the tears. This decreases the pH of the tears, creating an acid-like environment, causing eye irritation.
Cigarette/Cigar Smoke – Smoke is actually a cloud of very small particles. The irritation one gets from smoke is analogous to the irritation one would get pouring sand into your eye, althoughwith smaller particles so irritation on a much less intense scale.
Courtesy of the Doctors of Shady Grove Eye and Vision Care; Optometrists, Ophthalmologists and Opticians serving Rockville, Potomac and Gaithersburg Maryland suburbs of Washington DC. For more information or to schedule an eye doctor appointment visit youreyesite.com
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