Skin sensitizer
From KayakWiki
People who work in kayak shops, even if it is their personal garage, need to understand that some of the materials that a kayak builder must work with are toxic.
Most people understand that goop that comes in cans should not be tasted or eaten! Not unless there is a picture of a fork on the can and it says something about being "um um good"!
Dusts are also potential problems. It is really a good idea to keep fiberglass, epoxy, and cedar saw dust out of the lungs.
Some chemicals are toxic even when the only contact is through the skin. Some chemicals, like latex paint, are seldom a problem other than the unsightly mess that can get in the hair or on the skin. Others can burn the skin significantly - gasoline and powdered cement come to mind.
Oils on the skin (linseed, tung oils) can cause acne on the exposed skin.
Other chemicals can cause skin sensitization. The most common chemical which kayak builders come into contact with that does this is epoxy resin hardener. With skin sensitizers, the user might be able to have prolonged contact for days, weeks, or years before any problem is noted. But the chemical is like a time bomb with no way to look at the length of the fuse. Sooner or later, the body suddenly recognizes the chemical as a toxin and begins to react just like most people react to poison ivy, with large itchy water filled blisters. At the same time, the inside surface of the lungs may be sensitized, so that breathing even small amounts of epoxy dust (which contains hardener) causes swelling of the lining of the throat and lungs - just like smoke from burning poison ivy vines.
The way to avoid this sort of sensitization is to avoid frequent and prolonged contact with the chemical. Everyone gets a little chemical on their skin from time to time, but wearing protective gloves (without holes), cleaning the skin whenever some of the chemical gets on the skin, and using a respirator when sanding or when working with epoxy in enclosed spaces (like the inside of the hull when applying the hull/deck seam tape. The better your prevention program is, the less likely it is that you will become sensitized. (Cleaning the skin should be mechanical: wipe off with a paper towel, and then soap and water, NOT a solvent like acetone which leaches the hardener into your skin!)
Oh, by the way, the same thing works for poison ivy... So if you are lucky enough not to be sensitized already, stop those silly antics of pulling poison ivy out without gloves!!!! The stuff will bite you if you keep playing with it.

