Coal tar has been used as an ingredient in cosmetics and personal care products like shampoos, soaps, and skin creams for decades due to its anti-inflammatory and anti-dandruff properties. However, due to concerns over its potential to cause cancer, coal tar has been banned or restricted in these products in many countries.
This article summarizes the evidence behind these bans and restrictions in Europe, Canada, and the United States.
TLRD: Coal tar, a common ingredient in cosmetics, is facing restrictions in Europe, Canada, and the US due to concerns about its potential carcinogenicity. Despite evidence linking it to increased cancer risk, medically supervised treatments are still permitted.
Coal tar contains high levels of polycyclic aromatic hydrocarbons (PAHs), which have been shown to cause cancer in animal studies when applied to the skin over long periods . There is also some evidence linking topical coal tar use in humans to increased skin cancer risk [2,3]. However, the data is limited, especially for medically supervised coal tar treatments for skin conditions like psoriasis.
Nonetheless, many countries have imposed general bans or restrictions on coal tar in consumer cosmetic products as a precautionary measure against long-term daily topical exposure. At the same time, controlled medical uses of coal tar are still permitted in many cases under regulation as a prescription drug. This paper summarizes coal tar regulations and the rationale behind them in Europe, Canada, and the United States.
Evidence for Banning and Restricting Coal Tar
Multiple lines of evidence suggest coal tar is carcinogenic when applied topically:
- Animal studies show topical coal tar causes cancer in mice and rabbits .
Case reports link prolonged consumer use of topical tar preparations to increased skin cancer risk in humans .
Workers exposed to coal tar products have higher rates of cancer .
However, evidence directly linking medically supervised topical coal tar treatment for skin conditions to increased cancer risk is lacking:
- No definitive link shown between using topical coal tar to treat psoriasis under medical direction and increased skin cancer risk [9,10].
But, topical application results in some absorption and internal exposure to carcinogenic PAHs. This raises concerns about potential increased risk for internal cancers [7,8].
In summary, while coal tar is likely carcinogenic with chronic topical exposure, more research is needed on cancer risks with properly controlled medical uses.
Regulations in Europe
The European Union has banned or limited coal tar dyes and derivatives in cosmetics under the EU Cosmetics Regulation and Classification, Labelling and Packaging (CLP) Regulation [5,6].
The regulations appear intended as general precautions to limit long-term topical exposure from daily consumer use of cosmetics containing coal tar. They do not seem to specifically target medically supervised coal tar treatments.
Regulations in Canada
Canada has prohibited certain coal tar dyes and restricted other coal tar derivatives in cosmetics sold to consumers . Coal tar is regulated as a prescription drug for medical uses like medicated shampoos. This allows additional safety testing and labelling not required for cosmetics .
As in Europe, the regulations are likely meant as general precautions rather than targeting medically controlled coal tar treatments. Further research on carcinogenic risks from properly monitored medical coal tar uses could inform future regulations.
Regulations in the United States
In the United States, the Food and Drug Administration (FDA) regulates cosmetics and sets restrictions on ingredients like coal tar . The FDA prohibits high concentrations of coal tar in cosmetic products marketed to the general public . However, low concentration coal tar solutions can be sold over-the-counter as therapeutic products for skin conditions under FDA monograph regulations .
Additionally, high concentration prescription coal tar products are permitted under medical supervision for treating diagnosed skin disorders . This regulatory approach seems intended to limit general exposure from cosmetics, while allowing controlled medical access for skin disease treatment. More safety data could help guide optimal US regulations.
While evidence suggests topical coal tar is carcinogenic with chronic exposure, data directly linking medically supervised treatments to increased cancer risk is lacking.
General coal tar bans and restrictions in consumer cosmetics limit widespread exposure. However, controlled medical uses of coal tar are still permitted in many countries under drug regulations.
Further research clarifying cancer risks, especially with proper medical oversight, could help inform optimized regulations balancing safety and treatment benefits.
- Huff J. Long-term chemical carcinogenesis bioassays predict cancer hazards. Ann NY Acad Sci. 1999;895:56-79.
- Zackheim HS. Should therapeutic coal tar preparations be available over-the-counter? Arch Dermatol. 1978;114:125-6.
- Rook AJ, et al. Squamous epithelioma possibly induced by therapeutic applications of tar. Br J Cancer. 1956;10:17-23.
- Tremblay C, et al. Estimation of risk of developing bladder cancer among workers exposed to coal tar pitch volatiles in the primary aluminum industry. Am J Ind Med. 1995;27:335-48.
- SCCS (Scientific Committee on Consumer Safety). Opinion on coal tar pitch, high temperature. 2018;1657.
- European Chemicals Agency. Coal tar pitch, high temperature. Report No.: CLP-INV-251328-92-01/F.
- Government of Canada. Cosmetic Ingredient Hotlist: Prohibited and restricted ingredients.
- Government of Canada. Drug Product Database.
- US Food and Drug Administration. Authority over cosmetics.
- US Food and Drug Administration. Frequency of use of cosmetic ingredients.
- US Food and Drug Administration. CFR – Code of Federal Regulations Title 21.
- US Food and Drug Administration. Prescription coal tar drug products for the treatment of dandruff, seborrheic dermatitis, and psoriasis drug products containing coal tar.