Are Coal-Tar Shampoos Safe?

Home>
Specialties>
Dermatology>
Summary and Comment

Are Coal-Tar Shampoos Safe?

Polycyclic aromatic hydrocarbons (PAHs) are one type of hundreds of compounds found in coal tar. Based on the knowledge that exposure to PAHs is associated with an increased cancer risk, these researchers sought to determine whether coal-tar shampoos contribute to the PAH "body burden." Eleven healthy participants washed their hair with a coal-tar shampoo for 30 seconds twice in succession. Urine was collected on the day before the shampooing and on the following two days for measurement of 1-hydroxypyrine (1-OH-P), a PAH metabolite. The mean increases in totally excreted 1-OH-P on the first and second days after shampooing were 10 and 5 times the background values, respectively. The 1-OH-P values on day 1 were similar to those found in coke-oven workers at the end of a 7-day working period.

Comment: The finding that the urine concentration of carcinogenic PAH was as high in these subjects one day after shampooing as it is in coke-oven workers after seven days of work is, at first glance, extremely worrisome, especially given that coke oven workers have an increased rate of death from respiratory cancer. However, several observations render the significance of these results less clear. First, despite decades of use of coal-tar shampoos, especially in patients with psoriasis, there have been no reports of an increased incidence of respiratory cancer in these persons. Second, the shampoo that the researchers used has a PAH concentration at least 100 times higher than that of seven other commercially availa-ble coal-tar shampoos they evaluated. Still, the results of this study are cause for concern, and two questions the authors pose are worth repeating: Should coal-tar shampoos be sold without prescription? and, Should a limit be set for PAH in these shampoos? The answers are not yet known.

— JS Dover

Published in Journal Watch Dermatology February 1, 1995

Citation(s):

van Shooten F-J et al. Dermal uptake of polycyclic aromatic hydrocarbons after hairwash with coal-tar shampoo. Lancet 1994 344 1505-1506.

Medline abstract (Free)

Reader Remarks:

Review and add to remarks on this article

grover's disease
robert j. oboril, 1 Dec 2009 3:40 PM EST
does coal-tar shampoos relieve symptoms of grover's disease on the scalp, face, and chest?

Your Remark:

Reader Remarks are intended to encourage lively discussion of clinical topics with your peers in the medical community. We ask that you keep your remarks to a reasonable length, and we reserve the right to withhold publication of remarks that do not meet this standard.

The editors of Journal Watch may respond to Reader Remarks, but we cannot promise to respond to a particular remark.

Remark subject:*

Your remark:*

Fields marked with an * are required.

Name as you'd like it to appear:
First & middle initial:*

Last:*

Email address (will not
be published):*

Professional specialty:*

Place of work (optional):

Submitting a comment indicates you have read and agreed to the remark guidelines and declare:*

No competing interests

Or, the following competing interests (for example, financial stakes or professional relationships):

PRIVACY: We will not use your email address, submitted for a comment, for any other purpose nor sell, rent, or share your e-mail address with any third parties. Please see our Privacy Policy.

CLEAR erases anything you've added in any part of the form. CONTINUE allows you to check your entire post (and edit it if necessary) before submitting.

To ensure that your Reader Remark is not formatted as one long paragraph, precede new paragraphs with either a blank line or an indentation.