Sodium Lauryl Sulphate Health and Safety information

Sodium Lauryl Sulphate

Health and Safety Information on the Chemical

Acute Toxicity

Acute toxicity data in the rat show that SLS is harmful by the oral route (LD50 1200 mg/kg bw), and data in the rabbit and guinea pig show it is harmful by the dermal route (LD50 = ~600 mg/kg bw and >1200 mg/kg bw respectively).

Irritation

SLS is a skin and eye irritant in rabbits, and skin irritation has been observed in clinical studies in humans. Indeed in the human 4-hour patch test for irritation, SLS is used at 20% as a positive control to identify substances or preparations that would be on the borderlinefor classification as irritant. SLS is also reported  o irritate the respiratory tract.

Sensitisation

No data on skin sensitisation is available in these reviews. However, since OECD Test Guideline methodology for guinea pig skin sensitization predictive tests requires application of 10% SLS at induction to create local irritation for those test materials with no skin irritation potential, it is highly unlikely that SLS is a skin sensitiser as this could create concerns over potential cross sensitisation reactions at challenge with the test material.

Effects from Repeated Exposure

Oral (gavage) repeat exposure studies in rats showed the primary effect of SLS to be local irritation of the gastro-intestinal tract, with no effects seen at the 100 mg/kg bw/day dose level.

Genotoxicity

SLS was negative in an Ames (bacterial mutation) test, a gene mutation and sister chromatid exchange test in mammalian cells, as well as in an in vivo micronucleus assay in mice. The negative results from in vitro and in vivo studies indicate SLS does not interact with DNA.

Carcinogenicity

In the only carcinogenicity study available, SLS was not carcinogenic in Beagle dogs, though the short study duration and limited details provided limit the significance that can be attached to the data.

Reproductive Toxicity

No effect on fertility was seen in a study in male mice administered 100 mg/kg bw/day SLS, or on epididymal sperm in male mice administered SLS at a dose producing systemic toxicity: 1000 mg/kg bw/day. In developmental toxicity studies in the mouse and rabbit using doses of 0.2 to 600 mg/kg bw/day, total resorption of foetuses, increased litter loss and/or abortion were seen at 600 mg/kg bw/day in the presence of severe maternal toxicity. At 300 mg/kg bw/day no developmental toxicity was seen, though slight to moderate maternal toxicity was observed. Therefore, SLS is not considered a developmental toxicant, as the developmental effects seen were a secondary non-specific consequence of severe maternal toxicity.

Health and Safety Information on Formulations Containing Sodium Lauryl Sulfate

Information on formulations containing SLS at final tested concentrations ranging from 0.21 to 26% is available from studies for acute oral toxicity, and skin and eye irritation in animals, along with skin irritation and sensitisation clinical studies in humans. Together, these data support the findings on SLS that the chemical is of moderate acute oral toxicity, and irritant to the skin and eye in both animals and humans. Data in humans indicate SLS is not a skin sensitiser.

article source: NICNAS