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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

Three separate repeated dose studies via oral exposure are reported.  In the first, the resultant LOAEL and NOAEL values were 250 and 125 mg/kg bw/day, respectively.  In the second, the resultant LOAEL and NOAEL values were 115 and 40 mg/kg bw/day, respectively. And in the third, the resultant LOAEL and NOAEL values were 145 and 85 mg/kg bw/day, respectively.  This latter NOAEL represents the highest NOAEL below the lowest LOAEL in all of the studies and is therefore the appropriate NOAEL for use in the assessment.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Dose descriptor:
NOAEL
85 mg/kg bw/day
Study duration:
chronic
Species:
rat

Additional information

Three separate repeated dose studies via oral exposure are reported. In the first, male and female rats exposed to LAS via gavage daily for 28 days exhibited suppressed body weight gain, some serum biochemical effects, and some either decreased or increased organ weights relative to the controls in either the male or female high dose groups, but no mortalities or histopathological abnormalities. The resultant LOAEL and NOAEL values were 250 and 125 mg/kg bw/day, respectively.

In the second, male and female rats were exposed to LAS in the diet daily for 6 months. Diarrhea, suppressed growth, increased cecal weight, and degeneration of renal tubes characterized the highest dose group. Similar but less severe signs were seen in other doses with the exception of the lowest dose of 0.07%, which showed no adverse effects related to exposure to LAS. The resultant LOAEL and NOAEL values were 115 and 40 mg/kg bw/day, respectively.

And in the third, male and female rats were exposed to LAS in drinking water daily for 9 months. Again, body weight was suppressed in the highest dose group only. Significant decreases in transaminase activity and renal Na,K-ATPase was seen in the high dose group. The resultant LOAEL and NOAEL values were 145 and 85 mg/kg bw/day, respectively.

This latter NOAEL represents the highest NOAEL below the lowest LOAEL in all of the studies and is therefore the appropriate NOAEL for use in the assessment.

Justification for classification or non-classification

Based on the results of a series of repeated dose studies via either oral gavage or in the diet, the appropriate LOAEL and NOAEL values for use in the assessment are 145 and 85 mg/kg bw/day, respectively. These values do not meet the criteria for classification under either the DSD or CLP and therefore the substance is not classified.