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Administrative data

Description of key information

Acute oral toxicity (rat): LD50> 2000 mg/kg bw  (Cognis 1997; M. Hoyer)
Acute dermal toxicity (rat): LD50>5000 mg/kg bw (Cognis 1997; M. Hoyer)
Acute inhalative toxicity (rat): LC50 mixture of dimethylamides (mainly C8/C10): >3551 mg/m3 (Bayer 1991; J. Pauluhn)

Key value for chemical safety assessment

Acute toxicity: via oral route

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

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
LC50
Value:
3 551 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion
Dose descriptor:
LD50
Value:
5 000 mg/kg bw

Additional information

Valid data is available for the assessment of acute oral and acute dermal toxicity of N,N-Dimethyldecanamide. Acute inhalation toxicity was tested with a mixture of N,N-dimethyldecanamide and N,N-dimethyloctanamide (with traces of N,N-dimethyl-dodecanamide and N,N-dimethyl-hexanamide). Due to the fact that a high amount in the mixture was N,N-dimethyl-decanamide and the rest of the mixture are homologues with a lower and higher molecular weight which can be assumed to have a similar toxicological behaviour it is concluded that the mixture has an nearly similar toxicological behaviour like pure N,N-dimethyldecanamide.

Acute oral toxicity (N,N-dimethyldecanamide):

The acute oral toxicity in rats was determined according to OECD Guideline No. 420 (Cognis 1997; M. Hoyer).The study was initiated with a sighting study, in which one female rat was given N,N-Dimethyldecan-1 -amide in a 2000 mg/kg bw dose. Slight signs of toxicity were observed in this rat, therefore another female rat was given N,N-Dimethyldecan-1-amide in a 5000 mg/kg bw dose. This animal died under severe signs of toxicity on day 2.On the basis of the results from the sighting study it was decided to carry out the main study with one group consisting of five male and five female rats given a dose of 2000 mg/kg bw.All animals in the main study survived the treatment and showed slight signs of toxicity (clinical signs: pinched abdomen, piloerection). Gross necropsy revealed a gas filled intestine for three animals, distended vessel of testes in one animal, light margin of liver in two animals.

The oral LD50 of N,N-Dimethyldecan-1-amide in rats was found to be above 2000 mg/kg bw.

Acute dermal toxicity (N,N-dimethyldecanamide):

The acute dermal toxicity of N,N-dimethyldecanamid in rats was determined according OECD Guideline No. 402.The study was performed as a limit test with 10 Wistar rats (five males and five females). The rats were exposed to a single dermal dose of 5000 mg/kg bw for 24 hours followed by an observation period of 14 days. During the study clinical signs of reaction to the treatment were recorded daily. Body weight was recorded once a week. After the two week observation period the animals were killed and subjected to a gross necropsy examination. All animals in the main study survived the treatment and showed very slight signs of toxicity. Some females show stagnation in body weight increase all other rats had normal body weight gain. Clinical signs were only piloerections and post mortem inspection revealed no abnormalities. The dermal LD50 of N,N-dimethyldecanamidin rats was found to be above 5000 mg/kg bw.

Acute inhalation toxicity (mixture of dimethylamides):

A study for acute inhalation toxicity was conducted with "confidential substance name" in accordance with OECD Guideline No. 403 (Bayer 1991; J. Pauluhn). Therefore 5 SPF-bred Wistar rats were exposed (head/nose only) to 118.5; 586.4; 2007.6 and 3550.7 mg/m3 (analytical determined).Rats subjected to a concentration of 119 mg/m3 air tolerated the exposure without signs occurring. Rats exposed to 586 mg/m3 air exhibited a transient reddening of the nose on the day of exposure and reduced motility. Rats subjected to the max. tested concentration (3551 mg/m3 air; nebulisation of the undiluted test article) exhibited persistent signs causally linked to an irritation of the respiratory tract (slower breathing, serous nasal discharge, dyspnea, stridor, hypothermia). 3551 mg/m3 air was the range at which mortality started for male rats (1 of 5 died). The results of this study show that the respirable test article aerosol had a relatively low acute inhalation toxicity in the rat. The acute potential hazard of the respiratory tract is attributed to the potency of the test substance aerosol to act as a mucosa irritant.LC50 inhalation (aerosol) Rat (exposure: 4 h) > 3551 mg/m3 air.

It must also be noted that such a high concentration of 3551 mg/m3 (analytically determined) is created by a nominal concentration of 50000 mg/m3

Key study assignment:

As there is only one reliable and relevant study available for each endpoint, this study has been used as key study.

Justification for classification or non-classification

The available data for N,N-dimethyldecanamide and mixtures containing large amounts of N,N-dimethyldecanamide as well as shorter and longer homologues indicate a low potential for acute toxicity.

The available study indicate an oral LD50 (rat) > 2000 mg/kg bw (Cognis 1997; M. Hoyer) for male and female rats. Therefore N,N-dimethyldecanamide has not classified for acute oral toxicity according to GHS (Regulation (EU) 1272/2008) and also not classified according to EU-criteria DSD (67/548/EEC).

As the LD50 (rat) for acute dermal toxicity was >5000 mg/kg bw (Cognis 1997; M. Hoyer) and no death occurred, N,N-dimethyldecanamide has not to be classified acute dermal toxicity according to GHS (Regulation (EU) 1272/2008) and also not classified according to EU-criteria DSD (67/548/EEC)

As an acute inhalation toxicity test with a mixture of dimethylamides (main components N,N-dimethyloctanamide, N,N-dimethyldecanamide) reveals only one death in the highest administered concentration of 3551 mg/m3air, which reflexes the maximum attainable concentration (due to physical properties; nominal concentration 50000 mg/m3), the mixture has to not to be classified for acute inhalation toxicity according to GHS (Regulation (EU) 1272/2008) and EU-criteria DSD (67/548/EEC).

This classification is also assumed for pure N,N-dimethyldecanamide (see discussion).

Labelling for acute toxicity :

GHS: no classification

DSD: no classification