These Five Chemicals Can Get Under Your Skin

There are a lot of things that can get under your skin, either literally or metaphorically—from mosquitoes to that irritating coworker in the next cubicle. But some things that get under your skin can do more damage than spending Thanksgiving with your mother-in-law. Do you know how to identify them?

You can find out, using the National Institute for Occupational Safety and Health’s (NIOSH) “skin” notation, which you’ll find in the NIOSH Pocket Guide to Chemical Hazards. Additional information is available in a Skin Notation Profile, which summarizes all the relevant information used to arrive at the skin designation.

Yesterday we looked at what each designation means; today we’ll look at five chemicals with newly updated skin notations that can cause irritation or systemic effects.

Arsenic and Inorganic Arsenic-Containing Compounds, SK:DIR (IRR). Arsenic [CAS#: 7440-38-2] is used as a wood preservative and pesticide. Although the most toxic effects of arsenic result from ingestion, it can also be absorbed through the skin. Based on case reports and human studies that were found to be consistent with studies done in mice, NIOSH determined that chronic or high-dose dermal exposure to arsenic can result in irritant contact dermatitis.

Heptachlor, SK:SYS. Heptachlor [CAS#: 76-44-8] is an organochlorine pesticide that was banned from most commercial uses in 1988. It is still approved by the U.S. Environmental Protection Agency (EPA) for killing fire ants that are in buried power transformers. No dermal absorption studies exist for heptachlor, and a mathematical model predicted that the chemical is not likely to be absorbed through the skin. However, acute dermal toxicity studies in rats did indicate that heptachlor can be absorbed through the skin and can be acutely toxic but not acutely fatal.

Tetraethyl Lead, SK:SYS. Tetraethyl Lead (TEL) [CAS#: 78-00-2] is used in metals manufacturing. Data from toxicokinetic and acute toxicity studies demonstrates that TEL is absorbed through the skin and is systemically available. Limited evidence suggests that at high doses, TEL may cause health effects that include high blood sugar, porphyrinuria, dramatic reduction in body weight, and impairment of liver function.

Tetramethyl Lead, SK:SYS. Tetramethyl Lead (TML) [CAS#: 75-74-1] was once used as an octane booster in fuels but is no longer widely commercially used. In an oral exposure study, TML caused systemic liver and nervous system toxicity in rats; models indicate that it can be readily absorbed through the skin.

1-Bromopropane, SK:SYS-DIR (IRR). 1-Bromopropane (1-BP) [CAS#: 106-94-5] is used primarily as a solvent in vapor degreasing and cold-cleaning operations and as an adhesive and for coating spray applications. Based on a mathematical model and in vitro study, 1-BP is believed to be easily absorbed through the skin. Studies of exposed workers also indicated that 1-BP could be absorbed through the skin and contribute to systemic toxicity, although the workers were also exposed to airborne 1-BP. Animal studies show a range of toxic systemic effects. In addition, while skin models failed to show corrosivity, animal models indicated that 1-BP can cause skin irritation.

Tomorrow we’ll look at four more chemicals that can cause a broader range of effects or, in some cases, far more toxic effects as a result of dermal exposures.