What Is Coal Tar?
Coal tar is a thick, dark brown to black liquid that forms when bituminous coal is heated in the absence of air during the coking process. This high heat breaks the coal into gas, coke and a sticky resinous mix that is separated, collected and then refined. Chemically, coal tar is a complex blend of hundreds of aromatic hydrocarbons and phenolic compounds, many of which give it its characteristic smoky scent and viscous texture.
The use of coal tar for skin and scalp care dates back to the late 1800s when barbers and apothecaries noticed its ability to soothe flaky scalps and rough patches of skin. As personal care products grew in popularity, formulators adopted purified grades of coal tar for shampoos and ointments. Today, cosmetic manufacturers use highly processed fractions that meet strict purity standards, making them suitable for topical beauty products.
After collection, raw coal tar is distilled into fractions based on boiling point. The lighter fractions go to chemical feedstocks while the middle cuts, rich in polycyclic aromatic compounds, are further purified to remove undesirable elements. The resulting cosmetic-grade coal tar is then blended into finished products in low concentrations.
You will most often find coal tar in rinse-off items like shampoos, scalp masks and body washes aimed at controlling excess oil and flaking. It can also appear in targeted leave-on treatments for rough elbows or knees but is rarely used in everyday moisturizers or facial serums because of its strong color and scent.
Coal Tar’s Cosmetic Benefits/Uses
Coal tar serves a few key roles that make it useful in certain beauty products.
- Anti-Seborrheic: Helps slow down the overproduction of oil and skin cells on the scalp or body, which can reduce visible flakes and keep the skin surface looking clearer and less greasy.
- Antimicrobial: Its aromatic compounds create an unfriendly setting for some bacteria and fungi, helping formulas stay fresh on the shelf and supporting a cleaner skin environment when applied.
- Denaturant: Gives cosmetic alcohols an unpalatable taste so they are not misused, allowing brands to use alcohol as a solvent without the need for extra regulatory steps.
Who Can Use Coal Tar
Coal tar works best for oily, combination and normal skin that struggles with flaking or buildup. Dry or very sensitive skin may find it too strong because the tar’s aromatic compounds can feel slightly irritating or drying. People with open cuts or raw skin should also steer clear until the area has healed.
Because coal tar comes from the distillation of coal, not animals, it is considered suitable for vegans and vegetarians.
Pregnant or breastfeeding women should be cautious. Scientific data on topical coal tar during pregnancy is limited and some doctors prefer safer alternatives. This is not medical advice so anyone expecting or nursing should ask their healthcare provider before using products that contain coal tar.
Coal tar can make skin more sensitive to sunlight, especially right after application. Using sunscreen or covering the treated area when outdoors helps lower the risk of sunburn.
Children under two years old should not use coal tar products unless a pediatrician specifically recommends it.
Potential Side Effects/Adverse Reactions
Reactions to coal tar vary from person to person. The effects listed below are only potential outcomes and most users will not run into these issues when the ingredient is used at proper cosmetic levels.
- Skin irritation – redness, stinging or a burning feeling, especially on sensitive areas
- Dryness or tightness – the tar can strip natural oils if used too often
- Allergic contact dermatitis – rare itchy rash due to individual sensitivity
- Folliculitis – small pimple like bumps if the pores become blocked by heavy formulas
- Photosensitivity – increased chance of sunburn after exposure to UV light
- Temporary staining – dark residue on skin, nails or fabrics that usually washes off
If any of these side effects occur, stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 2/5
Coal tar itself is a viscous mixture that can sit on the skin surface and, in heavy leave-on ointments, may trap dead cells and oil. Most cosmetic formulas keep its level low and place it in rinse-off shampoos or lightweight gels, which lessens the chance of pore blockage. Overall, it carries a mild to moderate risk.
Because of that rating, coal tar is generally acceptable for acne-prone users in rinse-off products but could be tricky in thick leave-ons or if layered with other occlusive ingredients.
Formulation matters: when paired with non-greasy carriers and used as directed, its comedogenic impact drops further.
Summary
Coal tar’s primary roles in cosmetics are to calm excess oil and flaking, curb microbial growth and denature cosmetic alcohols. Its blend of aromatic hydrocarbons slows rapid cell turnover on the scalp or skin and creates an environment that discourages certain bacteria and fungi, helping products stay stable at the same time.
Despite these benefits, coal tar is a niche ingredient today. Its smoky scent, dark color and strict regulatory limits mean it shows up mostly in targeted scalp or body treatments rather than mainstream serums or creams.
At the concentrations allowed in cosmetics it is considered safe for most healthy adults, though those with sensitive skin, pregnant users or very young children should seek professional guidance before use. As with any new skincare step, do a small patch test first to be sure your skin plays well with the formula.