1 Pain that does not diminish with rest, and pain that may be worse at night than during the day. 2  Back pain along with constitutional symptoms, such as loss of appetite, unplanned weight loss, nausea, vomiting, or fever, chills or shakes.
Unstable chemicals. 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.
1 Peel the outermost layer of the onion down to the root, leaving the root as is. 2  Lay the onion cut side down on the cutting board. 3  Then use a knife to section the onion into 16ths, beginning with your knife â-inch away from the root and cutting straight down.