479 NEWS

Poisonous Plants and Movie Crews

IATSE Local 479 Summer Safety Series: people who work outdoors face a number of additional health safety dangers, from weather extremes to risk of disease. This article includes information collected from several agencies, including the Contract Services Administration Trust Fund (“CSATF”) Safety Bulletin #27, “Poisonous Plants”.

One of the hidden dangers of shooting at exterior locations is the plant life, specifically a genus of plants called Toxicodendrons, known for inducing rashes on exposed skin. In North America the most common of these plants are varieties of poison ivy, poison oak, and poison sumac. In Local 479’s jurisdiction, poison ivy is the most common, Atlantic poison oak is slightly less common, and the least common (but most toxic) is poison sumac.

Count yourself lucky if you have never suffered the ill effects associated with exposure to these plants, as most encounters result in wild bouts of itching and scratching. While some people only endure a mild rash, others find themselves covered in painfully tender blisters. In the most severe cases medical intervention may be required.

This article provides understanding for how the “poison” works, how it is transmitted, and how to mitigate its effects. The term “poison ivy” has become slang for the effects of exposure to these plants.

The Basics

If you are working on a big budget production, the locations and greens departments may coordinate to eliminate this family of plants from the area you will be working in, shielding the crew from danger. Experienced best boys will look for areas of potential exposure while on scouts and will plan to route cables around areas of likely contact.

But you cannot count on other people to protect you from exposure.

Try to stay away from all undergrowth. Attempt to keep your equipment in areas without leafy foliage, and be prepared to treat your skin and exposed clothing and equipment immediately if you believe that you have come in contact with plants in the Toxicodendrons family.

Download CSATF Safety Bulletin #27 “Poisonous Plants” [PDF]

Visual Identification of Poison Ivy, Oak, and Sumac

The old rhyme “leaves of three, let them be” is useful with poison ivy and generally (but not always) with poison oak, but poison sumac has an altogether different leaf structure resembling that of a leafy bush. All of these plants have different presentations throughout the year, depending on season, geography, sunlight levels, rainfall, and temperature.

Poison Ivy

Poison ivy generally grows as a small shrub or as a vine.

Leaf ID: Poison Ivy

Poison Oak

Poison oak is reputed to be an especially good mimic of neighboring plants, making it even more difficult to identify. It has been found as low ground cover but more often as a small shrub. It can even grow as a vine. The number of leaves on poison oak will typically be 3, but sometimes number as many as 7.

Leaf ID: Poison Oak

Poison Sumac

Poison sumac may have between 7 and 13 smooth leaflets on each stem.

Leaf ID: Poison Sumac

How does the “poison” work?

All the plants in genus Toxicodendrons produce a substance called “Urushiol”.

Urushiol is an oily resin that is secreted by these plants when their leaves or stems have been damaged – like when an electrician drags a cable across a poison ivy plant.

This video from the National Institute for Occupational Safety and Health (NIOSH) provides an easy to understand explanation of the chemistry involved when Urushiol makes contact with skin.

It takes time for Urushiol to penetrate through the skin (epidermis) to reach the dermis and initiate an allergic reaction, so areas of the body with thinner skin are likely to show symptoms sooner.

How is the “poison” transmitted?

There are only three ways of “catching” poison ivy:

  1. Direct Contact: directly touching the plant(s)
  2. Secondary Contact: contact with someone or something that has had direct contact with the plant(s) and still has Urushiol on them. This could range from clothes and shoes, to tools and even pets. The liquid inside of poison ivy blisters may be yucky but it does not include any contagion. Remember that the oil from the plant is the real culprit.
  3. Inhalation of burning plants. This can be the most dangerous way to encounter Urushiol.

In his book “Hail to the Chins: Further Confessions of a B Movie Actor”, Lodge 49 actor Bruce Campbell describes a low budget shoot on his own property in which the crew and their families were hit with an epidemic of poison oak:

“Some people reacted immediately with red rashes. Even the ones with no reaction unwittingly brought the toxic oil back home, where it would spread to their allergic spouses and children. Poison Oak got all over the cables that snaked through the forest, which meant that the poor grips and electricians working on the equipment trucks got infected – even if they hadn’t set foot in the woods.”

Your sensitivity to Urushiol can increase over time

One of the most interesting facts about poison ivy is that the very first time a person is exposed to Urushiol they may not have a reaction, as their body does not recognize the chemistry of the compound. It may take weeks before the body eventually identifies the substance as harmful. This is why subsequent and repeated exposures to Urushiol are more apt to invoke a faster and more pronounced hypersensitivity and allergic response.

Quick Facts

  • contact with Urushiol adversely affects 9 out of 10 adults
  • on average it only takes 100 nanograms of Urushiol to cause a rash
  • just 1 nanogram (billionth of a gram) can cause a rash for sensitive people
  • it can be transferred via contact with clothes, tools, pet fur, etc.
  • a rash may not develop for 1 to 2 days after initial exposure to Urushiol
  • it is not possible to become infected from someone else’s poison ivy blisters
  • don’t scratch: bacteria living under your fingernails can cause a skin infection.
  • without treatment it typically takes 2 weeks for all the allergic reactions to heal
  • in severe cases the symptoms may endure for a month or more

What to do if you think you have been exposed

If you think you may have been exposed to one of these plants there are several steps you should take immediately.

  • Wash the affected skin immediately using degreasing soap (dish detergent) and water. Scrub vigorously, rinse frequently. The sooner you remove the oil from your skin the greater the chance you stand of reducing the adverse effects. Scrub under your nails with a brush.
  • Your pharmacy may carry lotions and sprays designed to combat Urushiol:
    1. Traditional anti-itch remedies for suppressing itching include Calamine lotion, cortisone creams, and gels/salves made from the aloe vera plant.
    2. Oral anti-histamines can be effective for reducing the impact of Urushiol exposure.
    3. Some people use astringents like vinegar and witch hazel to help dry up the external rash.
    4. SeeLeaf.com offers revolutionary “detector” cloths that turn pink when exposed to Urushiol, helping you identify where the irritant may lurk on equipment or clothes. Note that this product is not intended to be used on skin. You can purchase the product here.
    5. Tecnu is a product that can be used on skin and should be applied as soon as exposure is suspected, well before a rash appears.
    6. Zanfel Poison Ivy, Poison Oak & Sumac Wash claims to binds itself chemically to Urushiol, allowing you to wash the oil away and reduce its effects on your skin.
    7. IvyBlock bills itself as the only “FDA-approved product that’s clinically proven to help prevent poison oak, ivy and sumac rashes before they start”
  • Never burn or breathe the fumes or smoke from burning poison ivy, oak, or sumac. The CDC provides additional guidance on using a NIOSH-certified respirator in cases where exposure to burning plants is unavoidable.
  • Remove, do not touch, and immediately wash any article of clothing or footwear or equipment that may have come into contact with the Urushiol compound. Remember that you are attempting to eliminate an invisible, oily substance and that anything that touches it may potentially help spread the oil to as yet unexposed skin.
  • If your pet(s) have been exposed to these plants they can spread the oils via contact with their fur. Isolate your pet to reduce their ability to contaminate the area. Shampoo your pet as soon as possible, using gloves and avoiding splashes.
  • If it’s too late and you are already suffering with a skin rash and blisters, it’s time to find a product to relieve the irritation. Old-fashioned remedies include oatmeal baths, the application of calamine lotion, hydrocortisone cream, and antihistamines. Newer remedies include Tecnu Rash Relief and Calagel Medicated Anti-itch Gel.
  • If these products do not relieve the severity of your rash contact your medical advisor or consult your doctor or an immediate care facility for treatment, which typically includes steroids.


The National Institute for Occupational Safety and Health (NIOSH): Poisonous Plants

The Mayo Clinic on Poison Ivy rash

Connecticut After School Network: Everything you didn’t want to know about poison ivy