Tetraethylammonium heptadecafluorooctanesulphonate

Endpoint summary

Description of key information

Several acute toxicity studies were performed with  tetraethylammonium heptadecafluorooctanesulphonate .
In the key study for acute oral toxicity a LD50 = 190 mg/kg bw (rat, male) was found. In another study in rats a LD50 = 632 mg/kg bw (female rats); LD50 > 200 mg/kg bw (male rats)  was determined. In a not assignable study (secondary literature) in rats acute oral LD50 values and 95% confidence limits were calculated for male rats (233 [160-339] mg/kg), females (271 [200-369] mg/kg) and combined male and female rats (251 [199-318] mg/kg). 
Acute inhalative toxicity was tested with the test substance in male rats, mice, hamsters, rabbits. Rats and mic were exposed whole body for 1 hours at room temperature  to a concentration of 1368 and 9337 mg/m³; hamster and rabbits were exposed whole body for 1 hours at room temperature  to a concentration of 1375 and 9087 mg/m³ of the test substance in an 400 l inhalation chamber. Mortality and clinical signs were recorded during a post-expsoure period of 7 days. Rats and mic were exposed whole body for 4 hours at room temperature  to a concentration of 1585, 1575 or 11612 mg/m³; hamster and rabbits were exposed whole body for 4 hours at room temperature  to a concentration of 1730 or 10325 mg/m³ of the test substance in an 400 l inhalation chamber. Mortality and clinical signs were recorded during a post-expsoure period of 7 days. In both studies no mortality was observed. In a not assignable study (secondary literature) PFOS dust was administered whole body for 4 h in air to Sprague-Dawley rats, 5/sex/group, levels of 1.89 to 45.97 mg/l PFOS to eight test groups. An LC50 = 5.2 (4.4 – 6.4) mg/l was determined.
a valid study for dermal toxicity determined a LD50 > 2000 mg/kg bw. At 2000 mg/kg bw one out of 10 animals died. 

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

200 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Dose descriptor:

LC50

Value:

1 000 mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

From the acute oral toxicity studies a LD50 > 200 mg/kg bw for male and female rats is assumed on a weight of evidence consideration.

In 2 studies on rats, mice, hamster and rabbits with whole body exposure for 1 and 4 hours no mortality was observed. In the 1 hour study a LC50 > 9337 mg/m³ (male rat + mouse), LC50 > 9087 mg/m³ (male hamster + rabbit) was determined. In the 4 hours study a LC50 > 11612 mg/m³ (male rat + mouse), LC50 > 10325 mg/m³ (male hamster + rabbit) was determined. An additional study on rats for 1 hour revealed an LC50 = 5.2 mg/l (5200 mg/m³). Following Haber's rule a conversion of the 1 hour LC50 to a 4 hour LC50 and based on a weight of evidence consideration a LC50 > 1 mg/l (rat) for PFOS dust seems justified.

In a acute dermal toxicity study 5 male and 5 female rats were exposed semicoocusively to PFOS for 24 hours. One of the male rats died after 11 days. Liver and kidneys of the deceased animal were light discolored.

Justification for classification or non-classification

Based on the results of the oral toxicity studies a LD50 > 200 mg/kg bw a LC50 > 1 mg/l for acute inhalation toxicity seems reliable.

Therefore a classification as Xn; R20/22 (GHS: Acute Tox 4, H 332; Acute Tox 3, H 301) is justified. In an acute dermal toxicity study,

1 of 10 animals died at 2000 mg/kg bw. According to the OECD TG 434 for GHS a classification as Acute Tox 5, H313 (may be harmful in contact with skin). However, this classification for acute dermal toxicity has no relevance for EU countries, because under EU CLP category 5 is not classified.