LINEAR ALKYLBENZENE SULFONATE (LAS) - UNEP Chemicals

OECD SIDS LINEAR ALKYLBENZENE SULFONATE (LAS)
Japanese); cited in: IPCS (1996); Environmental Health Criteria 169: Linear
Alkylbenzene Sulfonates (LAS) and Related Compounds. WHO, Geneva,
Switzerland.
Reliability: 4 This study is assigned a reliability score of 4 because the original report
was not available for review. However, the study was evaluated by IPCS
prior to inclusion in their criteria document
(r)
Species/strain: rabbit/New Zealand white
Sex: Female [X]; Male [ ]; Male/Female [ ]; No data [ ]
Administration: Dermal
Exposure period: 17 days (days 1 through 16 of gestation)
Frequency of treatment: Daily
Doses: 0.03, 0.3, or 3% (0.9, 9, or 90 mg/kg bw d)
Control group: Yes [X]; No [ ]; No data [ ];
Concurrent no treatment [X]; Concurrent vehicle [ ]; Historical [ ]
NOAEL Maternal: 0.03% (0.9 mg/kg bw d)
NOAEL teratogenicity: 3% (90 mg/kg bw d)
Results: Maternal toxicity:
At the high dose, local irritation was observed resulting in body weight loss
and hypersensitivity (i.e., animals were increasingly irritable). The medium
dose caused retarded body weight gain and hypersensitivity.
Teratogenicity:
At the medium and low dose, no differences were observed among the dose
groups and the control group with respect to number of litters, viable young,
litter weight, foetal weight, embryonic deaths, implantations, corpora lutea,
pre and post implantation embryonic loss. The high dose was associated with
slightly, but not significantly, higher foetal loss and lower litter size. The
incidences of major malformations, minor visceral or skeletal anomalies, and
skeletal variants were not different between controls and dose groups even at
maternal toxic doses.
Method: The dosage volume was 10 mL which was applied to an area of skin (12 x 20
cm) from which the fur was removed. The nominal doses were 0.9, 9.0, and
90 mg/kg bw/day. Thirteen rabbits per dose were used.
GLP: Yes [ ] No [X] ? [ ]
Test substance: LAS
Reference: Palmer, A.K., Readshaw, M.A. and Neuff, A.M. 1975b. Assessment of the
teratogenic potential of surfactants (Part III) – Dermal application of LAS
and soap. Toxicology 4:171-181.
Reliability: 2 Valid with restrictions
5.10 OTHER RELEVANT INFORMATION
(a)
Type: Toxicokinetics
Results:
35 8
S-LAS (15 x 10 cpm) was administered topically, once, onto the back skin
of rats and guinea pigs. Absorption and distribution in major organs and
blood were studied. Urine was collected 24 hours after topical application of
the test substance. In the guinea pig, the amount of 35 S excreted in the urine
was about 0.1% of the total administered dose. Organ distribution in the rat
was about 5 times greater than in the guinea pig, and "relatively large
amounts" of 35 S were noted in the liver and kidneys. Conclusion states that:
"when 0.2 to 0.5% LAS was topically applied once, approximately 0.1 to
0.6% was absorbed"; there was no accumulation in specific organs; the "test
chemical was quickly excreted in the urine after being metabolized".
UNEP PUBLICATIONS 303