Registration Dossier

Administrative data

Description of key information

Terphenyl, hydrogenated was very well tolerated after acute oral, inhalation and dermal dosing . LD50 values were systematically above the limit doses, therefore the test material is considered to be safe from an acute toxicity viewpoint.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
Value:
12 500 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
LC50
Value:
4 700 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion
Dose descriptor:
LD50
Value:
2 000 mg/kg bw

Additional information

A key study for acute oral toxicity was performed according to OECD 401 and GLP testing guidelines and was therefore considered to be reliable, relevant and adequate. No deaths resulted from an oral dosage of 10.000 mg/kg body weight of hydrogenated terphenyl to fasted male and female albino rats (Branch et al., 1980 – Monsanto study). LD50 was therefore higher than 10.000 mg/kg. Observations included hypoactivity, diarrhea, faeces-stained fur and urine-stained fur. Addition supporting studies ( Klimisch scores 3-4) provided following results: - hydrogenated terphenyl: >24.000 mg/kg in female rats (Clarck et al., 1979 – Literature) - Unknown composition: 17.500 mg/kg in male rats (Adamson and Weeks, 1973 – Literature) - Unknown composition: 12.500 mg/kg in male mice (Adamson and Weeks, 1973 – Literature) - hydrogenated terphenyl: 10.200 mg/kg in male and female rats (Monsanto, 1970 –IBT study). The latter study was not taken into account as IBT studies are considered to be unreliable unless otherwise stated (OECD-HPV manual on data quality). In conclusion, LD50 was systematically above the limit dose of 2.000 mg/kg body weight.

A key study for acute inhalation toxicity was performed according to OECD 403 and GLP testing guidelines and was therefore considered to be reliable, relevant and adequate. Rats were each exposed once for 4 hours to atmospheres of aerosolized hydrogenated terphenyl at mean exposure concentrations ranged from 2.5 to 4.7 mg/L air of hydrogenated terphenyl vapor/aerosol (Bechtel, 1966 – Monsanto study). Mortality was observed in 3 out of 12 rats at 4.7 mg/L. Observations included salivation, wet fur, discharges and/or encrustation about the nose and eyes, labored breathing, prostrate condition and fur coated with test material. By post-exposure day 14 all surviving animals were in apparent good health. There were no test material related terminal necropsy findings. The LC50 was greater than 4.7 mg/L. Another study was further available in rats exposed up to 11.1 mg/L air of aerosolized (Monsanto, IBT report, 1975). As described in the OECD-HPV manual on data quality, IBT studies are considered to be unreliable unless otherwise stated. Finally, another study was performed (Monsanto), however when concentration of test material in the air was determined gravimetrically and indicated that the animals were not exposed to test material during the exposure period. As a consequence the LC50 could not be determined. Therefore these studies were not taken further into account for safety assessment. In conclusion, based on the key study, LC50 was considered to be above the limit concentration of 5 mg/L air.

A key study for acute dermal toxicity was performed according to OECD testing guidelines and was therefore considered to be reliable, relevant and adequate. No deaths resulted from a dermal (24h occlusive) dosage of 2.000 mg/kg body weight of hydrogenated terphenyl to the shaved dorsal surface of 5 male and 5 female New Zealand albino rabbits of both sexes (Chow, 1979 – Monsanto study). LD50 was therefore higher than 2.000 mg/kg body weight. No treatment-related abnormalities were noted in any groups. Another study for acute dermal toxicity with hydrogenated terphenyl (Klimisch rating 3) was performed in 2 rabbits/sex/dose at doses up to 10.2 g/kg body weight (Monsanto, 1970 – IBT study). As described in the OECD-HPV manual on data quality, IBT studies are considered to be unreliable unless otherwise stated. Therefore this study was not taken further into account for safety assessment. In conclusion, LD50 was systematically above the limit dose of 2.000 mg/kg body weight.

Justification for classification or non-classification

As LD50 values were above limit doses, there is no need for classification.