What are the most common substances that cause allergic contact dermatitis?

Poison ivy, nickel. Poison ivy, poison oak, poison sumac other plants nickel or other metals medications antibiotics, especially those applied to the surface of the skin (topical) topical anesthetics other medications rubber or latex cosmetics fabrics and clothing detergents solvents adhesives fragrances, perfumes other chemicals and substance.
Nickel. Nickel allergy is one of the most common substances. It is found in costume jewelry, eyeglass frames, snaps etc. Another group of allergens are the preservatives and fragrances used in cosmetics. Some of the chemicals used in latex products such as gloves, balloons, catheters etc. Can cause problems. They are the additives in the products not usually the latex itself.
Skin Irritants. A list of the top culprits that trigger skin reactions, or contact dermatitis. Some cause symptoms like redness, itchy skin, or inflammation.Some are triggered by an individual's allergy (contact allergic dermatitis) while other chemicals affect everyone (contact irritant dermatitis). http://www.webmd.com/skin-problems-and-treatments/features/dirty-dozen#1.