Interesting facts about poison ivy, oak and sumac:
- Between 75 percent and 85 percent of all humans are potentially allergic to poison ivy, oak and sumac. They will get a rash with an adequate dose. About 50 percent can get it from a normal brush with the plants or secondhand contact.- Every state in the United States - except Alaska, Hawaii and Nevada - is home to one or more of poison ivy, oak and/or sumac.
- There are two poison ivies: one in the eastern United States, one nearly everywhere; one is a bush, one is a vine (but sometimes a bush). There are two poison oaks, one eastern, one western. There is one poison sumac, which inhabits the swamps and bogs of the eastern United States.
- Urushiol (oil from the plants causing dermatitis) is the fiercest allergen known. It has been determined that 1/1,000th of a milligram, a microgram, was enough to cause a rash. In other words, a whole ounce of urushiol can cause a rash in 28 million people, and a drop the size of a pinhead can cause a rash in about 500.
- Presently, the only sure remedy is to recognize and avoid the plants. "Leaflets three . . . " is little help when the occasional leaf will bear up to 11 leaflets.
- These poisonous plants never grow above 5,000 feet elevation.
- When insect chewing releases the oil it may leave spots like black shiny beads on the leaves.
- Poison ivy, oak and sumac are misnamed. They are not ivies nor oaks, and there is not a drop of poison in them or in poison sumac. Urushiol, which causes the skin problem, is not poisonous. The rash is an allergy attack, a contact dermatitis (skin inflammation) that afflicts only people who have developed an immune response to an otherwise harmless oil.
- Once sensitized, by one or many exposures, the next contact will provoke a rash that will return with greater severity at each later contact. Usually, the longer the time between exposures, the less violent the reaction.
- Like all allergies, urushiol dermatitis can be treated but not cured.
- Urushiol dermatitis is particularly hazardous to forestry and utility workers, farmers and ranchers. The U.S. Forest Service says that it accounts for at least 10 percent of the service's lost time injuries. The percentage is much higher in bad fire years. Exposure to smoke on the fire-line has caused dermatitis over the entire body, respiratory tract inflammation, fever, temporary blindness and even death from throats swollen shut.
- Nobody knows how many people get urushiol dermatitis each year. Dr. William Epstein at the University of California Medical School, San Francisco, has estimated between 40 and 60 million cases occur each year.
- Urushiol dermatitis differs from other allergies in several ways: First, as much as 85 percent of the population are potentially susceptible to it; 50 percent are likely to get it directly from the plants. Second, urushiol dermatitis victims typically are not allergic to anything else. Half of all allergics, particularly eczema victims, are entirely resistant to urushiol dermatitis. Third, as with most allergies, parents who are insensitive to it may have sensitive offspring.
- Urushiol dermatitis works faster on warm days because the pores of the skin open and help urushiol to penetrate, because the oils in perspiration may soften or partially dissolve it, and because people usually wear less protective clothing on warm days.
- Wash with lots of cold water. Cold water closes the skin's pores and inactivates urushiol's chemical reaction a little. Using warm water opens the pores and stimulates the circulation.
- Alcohol is recommended and serves as an organic solvent. Alcohol may also pick up and flush out some of the oil that has soaked into the fat chambers of the skin's sebaceous glands.
- Solvents like gasoline, kerosene and turpentine are recommended for up to four hours after contact to remove urushiol molecules.
- If it is too late to remove the oil (from one minute to several hours), all the soap, water, alcohol or gasoline won't prevent a rash.
- None of these "cures" work: ammonia, banana peel, prepared mustard, chlorine bleach, buttermilk, canned pineapple, lysol, strychnine, clear nail polish, hair spray, meat tenderizer, hardwood ashes, green bean leaves, white shoe polish, marshmallows, toothpaste, bacon grease, externally applied vitamin E or horse urine.