Know Your Poisonous Plants: Preventing exposure to hazardous vegetation

By Tom O'Connor | Sep 15, 2023
Getty Images / Natalia Smuriakova
Electrical and lineworkers run the risk of encountering brush overgrowth and wild plant life, including some poisonous plants, while on the job. Being able to identify and avoid contact with these hazards can help prevent exposures. 

Electrical and lineworkers run the risk of encountering brush overgrowth and wild plant life, including some poisonous plants, while on the job. Nearly 50,000 people report injuries resulting from contact with these types of plants each year. Although very few of these instances result in hospitalization, reactions can be extremely painful and result in time away from the job. Being able to identify and avoid contact with these hazards can help prevent exposures. 

There are many native and exotic plants that are poisonous when ingested or touched. The most common problems with poisonous plants occur when skin comes into contact with the sap-oil on the leaves, stems or roots of poison ivy, poison oak, poison sumac, giant hogweed or poison hemlock. When working outdoors, encountering them is a major risk.

Leaves of three, let it be

Poison ivy is one of the most common poisonous plant species. It is found throughout the lower 48 states, except California. It grows in forests, fields, wetlands, stream banks, roadsides and in urban environments like parks and backyards. Eastern poison ivy has a hairy, ropelike vine with three shiny green leaves budding from one small stem. Western poison ivy is typically a low shrub with three leaves that do not form a climbing vine. It may also have yellow or green flowers and white to green-yellow or amber berries on it. 

Poison oak is found primarily in the Southeast and West Coast. It is a shrub with “leaves of three,” similar to poison ivy. However, Pacific poison oak may be vine-like, have yellow or green flowers and clusters of green-yellow or white berries. 

Poison sumac is most commonly found growing along the Mississippi River and in boggy, swampy areas in the Southeast. It usually looks like a woody shrub with stems containing 7–13 leaves arranged in pairs. Additionally, it can have glossy, pale yellow or cream-colored berries. 

Giant hogweed and poison hemlock are dangerous invasive species. Giant hogweed has spread throughout the Northeast and Northwest. It can grow to 14 feet or higher, with hollow, ridged stems 2–4 inches in diameter with dark reddish-purple blotches and coarse white hairs. Its large leaves can grow several feet long, and the large white flower heads can grow up to 2½-feet wide. 

Poison hemlock is found throughout the lower 48 states. It has thick, smooth, stems with purple splotches, clusters of small white flowers and fern-like leaves. 

How to stay safe on the job

To protect against these plants, wear long sleeves, long pants, boots and gloves. After working outdoors, wash any exposed clothing separately in hot water with detergent. Tools should also be cleaned with rubbing alcohol or soap and lots of water. Oil can remain active on an object’s surface for up to 5 years. Workers may consider using barrier skin creams, such as lotions containing bentoquatum. 

If a worker is exposed to one of these plants, it is imperative to understand how to identify and treat the symptoms. 

The oil from poison ivy, oak, sumac and hemlock causes an allergic reaction on the skin. Symptoms may include red rash, swelling, itching, bumps, patches, streaking or weeping blisters. 

Contact with giant hogweed causes more severe symptoms than other common poisonous plants. Its sap, in combination with moisture and sunlight, can result in severe skin and eye irritation, painful blistering, permanent scarring and blindness. Reactions often appear like third-degree burns. Symptoms begin to exhibit themselves within 48 hours of contact, which typically occurs by brushing against the bristles on the stem or breaking the stem or leaves.

These reactions can occur from direct contact or indirect contact from touching tools or clothes contaminated with the oil. Even a very small amount can cause a severe reaction. Never burn any of these plants, as this can result in inhalation of vaporized oils. 

Poison hemlock is particularly dangerous if inhaled, ingested or absorbed by the mucous membranes in the nose or mouth. It can cause severe and potentially fatal respiratory distress, dizziness, trembling and paralysis. If contact is suspected, seek medical help immediately.

If a worker does come into contact with a poisonous plant, they should clean their skin with rubbing alcohol, specialized poison plant washes, degreasing soap or detergent and lots of water. It is important to rinse frequently and scrub under the nails with a brush.

To treat symptoms, apply wet compresses, calamine lotion or hydrocortisone cream to the skin to reduce itching and blistering. Avoid applying lotion to broken skin or open blisters. Oatmeal baths can also help to relieve itching. 

Additionally, over-the-counter antihistamines such as Benadryl can help relieve itching. In severe cases, or if the rash is on the face or genitals, professional medical attention should be sought. If the exposure results in difficulty breathing or the victim has had a severe reaction in the past, call 911.

Header image: Getty Images / Natalia Smuriakova

About The Author

O’CONNOR is safety and regulatory affairs manager for Intec, a safety consulting, training and publishing firm. Reach him at [email protected].





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