My brother has an allergy to epoxy, he gets welts between his fingers and toes, first then welts elsewhere blood is close to the surface. He gets the reaction from everything from unmixed resin to dust from sanding.
http://www.fram.nl/workshop/controlled_vacuum_infusion/allergy.htm
Chemical Agents causing Allergy. The component most commonly causing an allergic reaction is the resin. Between 2-4% of people not employed in the epoxy industry will have a positive skin test to the resin component. A higher percentage of worker in the epoxy industry test positive. Some formulations of epoxy acrylates (aka vinyl esters) used in dental work and printing have lead to contact allergies.
http://www.rc-soar.com/articles/safety/epoxyallergy.htm
Avoid contact with eyes, skin, and clothing. Good personal hygiene. is necessary. Wash hands and contaminated areas with water and soap before leaving the work. site. Pregnant women should not work with the product, if there is the least risk of exposure.
http://www.eplastics.com/pdf/envirotex-lite-resin.pdf
A syringe of 5-minute epoxy glue, containing separate compartments for the epoxy resin and the hardener. Structure of the highly reactive epoxide group present in all epoxy resins.
https://en.wikipedia.org/wiki/Epoxy
Q: I've read that exposure to epoxy leads to allergic sensitization, but haven't read what kind of sensitization occurs. A: Contact dermatitis is by far the most common. Caused mostly by skin exposure to the hardener, but also to a lesser extent to the resin.
http://www.fram.nl/workshop/controlled_vacuum_infusion/allergy.htm
Epoxy is either any of the basic components or the cured end products of epoxy resins, as well as a colloquial name for the epoxide functional group. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups.
https://en.wikipedia.org/wiki/Epoxy
Skin allergies in children were reported in 9.4 million cases, or a total of 12.6 percent of the children in the population, in 2010. More than half (54.6 percent) of the people reporting a survey completed in the U.S. indicated that they had positive reactions to one or more allergens. Allergic rhinitis (hay fever) affects between 10 and 30 percent of all adults in the U.S. and as many as 40 percent of children.
http://www.healthline.com/health/allergies/statistics
In the general population, there is less than a 1 percent incidence, while in the healthcare industry, the rate is 5 to 15 percent. Milk allergies are most common in children with 2.5 percent of children under the age of 3 having an allergic reaction to milk.
http://www.healthline.com/health/allergies/statistics
I have been told that there are two kinds of epoxy, one that causes skin allergies and one that causes liver problems, West epoxy is of the skin variety, Saf-t-Poxie(sp) is of the liver variety. My own personal reaction is severe thirst and lack of appetite for a few hours.
http://www.fram.nl/workshop/controlled_vacuum_infusion/allergy.htm
Structure of a cured epoxy glue. The triamine hardener is shown in red, the resin in black. The resin's epoxide groups have reacted with the hardener and are not present anymore. The material is highly crosslinked and contains many OH groups, which confer adhesive properties.
https://en.wikipedia.org/wiki/Epoxy
percent of population allergic to resin and hardener
There are between 2 and 4 percentage of population who are having an allergy from resin and hardener.  2 to 4 percent of the population is allergic to resin and hardener.