1 Sodium nitrate is a type of salt, naturally found in Chile and Peru. 2  It can also be created in a lab. 3  Sodium nitrite is also a type of salt, but is not found naturally and is created in a lab or as a byproduct of two other chemical reactions (i.e. when sodium nitrate is added to food and reacts with existing chemicals).
Eczema on the ear or in the ear can initially be caused by the skin being extra sensitive. Often the natural oil is stripped away through over cleaning or aggravated by getting water in the ear, wearing ear plugs, using cotton swabs or Q-tips or from the chemicals in shampoos, soaps and even hair spray.
1 Xerotic (dry skin) eczema: When the skin becomes pathologically dry, it will crack and ooze. 2  Seborrheic eczema: It produces a rash on the scalp, face, ears, and occasionally the mid-chest in adults. 3  In infants, in can produce a weepy, oozy rash behind the ears and can be quite extensive, involving the entire body.