Question

While cutting onions why do tears start flowing from our eyes What is in onion that it makes our eye to flow tears

Answer 1

Onions produce the chemical irritant known as syn-propanethial-S-oxide. It stimulates the eyes' lachrymal glands so they release tears. Scientists used to blame the enzyme allinase for the instability of substances in a cut onion

Answer 2

Onion contains weak acid. while cutting onion some particles of onion juice reach our eyes and irritate it.