Creosote is a dark, oily substance used primarily as a wood preservative, especially for utility poles and railway sleepers. It is derived from the distillation of coal tar and contains a complex mixture of chemicals, including polycyclic aromatic hydrocarbons (PAHs), phenols, and cresols. Creosote has been recognized by health and environmental agencies worldwide as a hazardous substance with potential to cause significant harm to humans and ecosystems.

 

Creosote is classified as a category 1B carcinogen. This means that there is evidence that it has the potential to cause cancer in humans. It can also be toxic if swallowed or if it comes into contact with skin.

 

According to hazard information provided by manufacturers:

 

This (Creosote) substance is toxic if swallowed, causes severe skin burns and eye damage, is toxic in contact with skin, is suspected of causing genetic defects, may cause damage to organs through prolonged or repeated exposure, is harmful if inhaled, is harmful to aquatic life with long lasting effects, causes serious eye irritation, may cause an allergic skin reaction and causes skin irritation.

 

 

 

 

The European Commission has also highlighted “significant environmental risks when wood treated with creosote comes into direct contact with soil or water”.

 

https://ec.europa.eu/commission/presscorner/detail/en/ip_11_925

 

Human Health Risks of Creosote Exposure

 

Exposure to creosote can occur through inhalation of vapors, skin contact, or ingestion of contaminated water or food.

The following are the primary health risks associated with creosote:

 

1. Respiratory Issues

 

Inhalation of creosote vapors can cause irritation of the respiratory tract, coughing, throat pain, and in chronic cases, long-term lung damage. Studies have reported increased cases of bronchitis and asthma in populations living near creosote treatment facilities.
Reference: https://www.ncbi.nlm.nih.gov/books/NBK606215/

 

2. Skin and Eye Irritation

 

Creosote is corrosive to skin and eyes. Direct contact can cause burns, rashes, and sensitivity to sunlight (photosensitization). Creosote exposure has led to corneal damage in extreme cases.
Reference: https://wwwn.cdc.gov/TSP/ToxFAQs/ToxFAQsDetails.aspx?faqid=65&toxid=18

 

3. Carcinogenic Properties

 

Creosote contains several PAHs that are classified as probable or known human carcinogens. Long-term exposure has been associated with increased risks of cancer. The International Agency for Research on Cancer (IARC) has classified coal tar creosote as a Group 1B carcinogen.
Reference: 

https://www.ncbi.nlm.nih.gov/books/NBK606219/

https://bluefrogscientific.com/chemical-regulatory-news-and-views/uk-biocides-hse-consultation-there-viable-alternative-creosote#:~:text=Creosote%20is%20classified%20as%20a%20Carcinogen%20Category,be%20banned%20unless%20certain%20conditions%20are%20met.

 

4. Liver and Kidney Damage

 

Animal studies have demonstrated liver enzyme elevation and histological liver damage following creosote exposure. There is also evidence of kidney impairment, with signs of nephrotoxicity due to metabolite accumulation.
Reference: https://www.atsdr.cdc.gov/toxprofiles/tp85.pdf

 

5. Neurological and Immune Effects

 

Chronic exposure may cause headaches, dizziness, fatigue, and potential neurotoxic effects. There is also evidence of immune suppression related to certain phenolic compounds in creosote.
Reference: https://pubmed.ncbi.nlm.nih.gov/10420740/

 

Environmental Risks of Creosote

 

1. Soil and Groundwater Contamination

 

Creosote can seep into soil and leach into groundwater, where its chemical components persist for decades. Contaminated sites often require long-term remediation efforts.

Reference: https://archive.epa.gov/epawaste/hazard/wastemin/web/pdf/creosote.pdf

 

2. Water Pollution

 

Creosote is highly toxic to aquatic organisms. Even low levels of PAHs can cause lethal and sub-lethal effects in fish and amphibians. It affects reproduction, development, and behavior in exposed species.
Reference: https://www.sciencedirect.com/science/article/pii/S0025326X12003068

 

3. Air Emissions

 

Volatile components of creosote evaporate into the air, particularly on warm days. These emissions can drift into nearby residential areas and lead to inhalation exposure.
Reference: https://www.osha.gov/chemicaldata/creosote

 

4. Wildlife Harm

 

Creosote can bioaccumulate in wildlife, impacting food chains. Exposure in soil and aquatic environments can be fatal for insects, invertebrates, birds, and mammals.
Reference: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1519428/

 

Risks to Communities Living Near Wood Treatment Plants

 

Residents living near wood treatment plants are at increased risk of chronic creosote exposure. The air can carry vapors from treated wood, and spills or leaks may lead to soil and water contamination.

 

Some studies have been published on the specific health effects experienced by residents living near to wood treatment plants.

 

Dahlgren et al. (2003) , for example, found exposed subjects had significantly more cancer, respiratory, skin, and neurological health problems than the population generally. Physician histories revealed that the residents had a significantly greater prevalence of mucous membrane irritation, and skin and neurological symptoms, as well as cancer. (Exposed versus unexposed, cancer 10.0% versus 2.08%, bronchitis 17.8% versus 5.8%, and asthma by history 40.5% versus 11.0%)

 

References:

 

 Health effects on nearby residents of a wood treatment plant –

 

https://www.sciencedirect.com/science/article/abs/pii/S0013935102000658

 

Exposure Assessment of residents living near a wood treatment plant –

 

https://www.sciencedirect.com/science/article/abs/pii/S0013935102000646?via%3Dihub

 

Examples include:

 

– Houston, Texas: Elevated cancer rates reported in the Fifth Ward linked to historic creosote contamination from a Union Pacific rail yard.

 

– Carbondale, Illinois: Residents living near an old creosote site reported cancer and respiratory issues even decades after closure.

 

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