Neodymium di(2-ethylhexyl) phosphate

Endpoint summary

Description of key information

LD50 oral, rat > 2000 mg/kg bw
LD50 dermal, rat > 2000 mg/kg bw

Additional information

Neodymium tris(di-2-ethylhexylphosphate) was tested in one oral and one dermal acute toxicity study, both performed according to internationally recognised guidelines and GLP, scored as validity 1 according to Klimisch criteria, and considered as key studies acceptable for the assessment.

 

Acute toxicity: oral

In an acute oral toxicity study according to OECD 423, EC B.1 tris, US/EPA/OPPTS 870.1100 and GLP (CIT report 32229 TAR, 2007), scored as validity 1 according to Klimisch criteria, groups of fasted 8-week old Sprague-Dawley rats were given a single oral dose of neodymium tris(di-2-ethylhexylphosphate) in corn oil at the dose of 300 and 2000 mg/kg bw (3 and 2x3 females, respectively). Animals were observed for 14 days. Clinical signs and mortality were checked frequently during the hours following administration of the test substance, and at least once a day thereafter. Body weight was measured just before administration of the test substance on day 1 and then on days 8 and 15.

No mortality occurred during the study.

At 300 mg/kg, piloerection and dyspnea were noted in all the animals one hour after treatment. Piloerection was still observed 2 hours after treatment. At 2000 mg/kg, piloerection was noted in 3/6 females 4 hours after treatment only.

No other clinical signs were noted thereafter, until the end of the observation period.

A slightly lower body weight gain was noted between day 8 and day 15 in 1/6 females treated at the dose-level of treated at 2000 mg/kg, when compared to historical control animals. The overall body weight gain of the other animals treated at the dose-level of 300 or 2000 mg/kg was not affected by treatment with the test item.

At necropsy, no apparent abnormalities were observed in any animal.

Under the experimental conditions, the oral LD50 of the test item neodymium tris(di-2-ethylhexylphosphate) was higher than 2000 mg/kg in rats.

 

No classification for acute oral toxicity is warranted based on the absence of mortality up to 2000 mg/kg bw, according to the criteria of Annex VI Directive 67/548/EEC or UN/EU GHS.

 

Acute toxicity: dermal

In an acute dermal toxicity study according to OECD TG 402, EC B.3, OPPTS 870.1200 and GLP (CIT report No.33192 TAR, 2007), scored as validity 1 according to Klimisch criteria, a group of 8-week old Sprague-Dawley rats (5/sex) were applied a single dermal dose of undiluted neodymium tris(di-2-ethylhexylphosphate) at the dose of 2000 mg/kg bw (limit test) under a semi-occlusive dressing applied for 24 hours, and observed for 14 days. Clinical signs and mortality were checked frequently during the hours following administration of the test substance, and at least once a day thereafter. Body weight was measured just before administration of the test substance on day 1 and then on days 8 and 15. Local tolerance was also observed from Day 2.

 

No deaths and no systemic clinical signs were observed during the study.

Crusts were noted in one female from day 11 until day 15 (end of the observation period).

When compared to historical control animals, a slightly lower body weight gain was noted in 1/5 females between day 8 and day 15. The overall body weight gain of the other animals was not affected by treatment with the test item.

No apparent abnormalities were observed at necropsy in any animal.

Under the experimental conditions of this study, the dermal LD50 of the test item neodymium tris(di-2-ethylhexylphosphate) was higher than 2000 mg/kg bw in rats.

 

No classification for acute dermal toxicity is warranted based on the absence of mortality up to a limit dose level, according to the criteria of Annex VI Directive 67/548/EEC or UN/EU GHS.

 

Acute toxicity: inhalation

No acute inhalation toxicity study is available. However this study can be waived based on column 2 adaptation (Reach regulation, Annex VIII, section 8.5), and because exposure of humans via inhalation is unlikely; handling of the registered substance does not produce vapour, aerosols or droplets. Furthermore, the substance is produced as an intermediate under strictly controlled conditions, thus no additional testing is required.

Justification for classification or non-classification

Based on the data available which induced no mortality in the rat following a single exposure by oral and dermal route up to a limit dose of 2000 mg/kg bw, neodymium tris(di-2-ethylhexylphosphate) should not be classified for acute toxicity via the oral and dermal route as defined by the criteria of Annex VI Directive 67/548/EEC or UN/EU GHS classification criteria.