Reaction mass of N,N-dimethyldecan-1-amide and N,N-dimethyloctanamide

Endpoint summary

Description of key information

Acute oral toxicity (rat): LD50> 2000 mg/kg bw  (Clariant 1993, Hoffmann)

Acute dermal toxicity (rat): LD50 (male): > 2000 mg/kg bw  (Weight of evidence usinf BASF SE 2012; Bayer 1995, Bomann; Cognis 1997, Hoyer))

Acute inhalation toxicity (rat): >3551 mg/m3 (Bayer 1991; J. Pauluhn)

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well conducted and documented study according to current guidelines under GLP. Original report only in german.

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: HOECHST AG, Kastengrund, SPF-Zucht, Strain: Hoe: WISKf(SPF71)
- Age at study initiation: 7 weeks (male), 8 weeks (female)
- Weight at study initiation: 177g (male), 179g (female)
- Fasting period before study: 16h prior and 4h after dosing
- Housing:airconditioned room, housed in macrolon cages (Tpy 4) on wood chips in group of 5 animal
- Diet (e.g. ad libitum): Altromin 1324, ad libitum
- Water (e.g. ad libitum): Tap water from plastic bottles, ad libitum
- Acclimation period: no, as animals were received from own breeding

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±3°C
- Humidity (%):50±20%
- Photoperiod (hrs dark / hrs light): 12h

Route of administration:

oral: gavage

Vehicle:

other: sesame (seed) oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: adapted to 2000mg/kg bw
- Amount of total volume applied to animal (if gavage): 10ml/kg bw
- Concentration (w/v): 20%

MAXIMUM DOSE VOLUME APPLIED: 10ml/kg bw

DOSAGE PREPARATION (if unusual): The test item was mixed with sesame seed oil, homogenicity and stability in the vehicle was verified.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: due to the assumed low toxicity of the test item the highst dose was conducted as a limit test

Doses:

2000mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

one female died on application day

Clinical signs:

other: Unspecific symptoms, adverse effects on motion sequence, respiration and reflexes were observed. The animal showed also abdominal and letaral position, lid narrows, epiphora, reduced surface temperature and signs of stupor.

Gross pathology:

Necropsy of died animal shows liver colouring and lobular pattern and diffuse redness of the gastric mucosa. Necropsy of the survived animals reveals no macroscopic visible alteration.

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: other: EU GHS

Conclusions:

An LD50 above 2000mg/kg bodyweight can be concluded from the experiment.

Executive summary:

To investigate the acute oral toxicity of Hoe S 4166 the test substance was applied via gavage to male and female wistar rats according to OECD 401 under GLP.

One female died in the 2000 mg/kg on application day. Additional to unspecific symptoms adverse effects on motion sequence, respiration and reflexes were observed. The animal showed also abdominal and letaral position, lid narrows, epiphora, reduced surface temperature and signs of stupor. On day 7 after application all surviving animals were free of symptoms. The body weight gain was not affected.

In result a Dosis letalis media (LD50) above 2000mg/kg bodyweight can be drawn from the experiment.

Necropsy of died animal shows liver colouring and lobular pattern and diffuse redness of the gastric mucosa. Necropsy of the survived animals reveals no macroscopic visible alteration.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

see Discussion

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study according to OECD guideline with GLP

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann/ Borchen 7 District of Paderborn / Germany
- Age at study initiation: between 2-3 months old
- Weight at study initiation: The rats had a mean starting weight of approx. 170 to 210 g.
- Fasting period before study:
- Housing: Makrolon® cages type III, 5 animals per cage
- Diet (e.g. ad libitum): ad libitum ;"Altromin" 1324 Diet for Rats and Mice
- Water (e.g. ad libitum): ad libitum; tap water
- Acclimation period: at least 4 days until the start of the treatment


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22° ± 2 °C
- Humidity (%): approx. 50 %
- Air changes (per hr): approx. 10 times per hour
- Photoperiod (hrs dark / hrs light): 12-hour artificial lighting from 06.00 to 18.00 hrs GET

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose/head only

Vehicle:

other: unchanged for high concentration; mixture with polyethylene glycol 400 - ethanol for low concentrations

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: The aerosol was sprayed under dynamic conditions into a cylindrical inhalation chamber with baffle
- Exposure chamber volume: The PVC inhalation chamber had the following dimensions: diameter = 30 cm, height = 28 cm (volume: approx. 20 liters)
- Source and rate of air/Method of conditioning air: The compressed air was produced with two in-parallel Boge compressors type SB 270/15/350D. The air was fully conditioned automatically by an in-line VIA compressed air dryer type A 110, i.e. water, dust and oil were removed.
- System of generating aerosols:The aerosol was generated by means of a nozzle (combination nozzle, Rhema Labortechnik Co.) and conditioned compressed air. A nominal 200 pi spray solution/10 liters air per min (dispersion pressure approx. 600 kPa) was nebulized under dynamic conditions into the baffle of the inhalation chamber.
- Method of particle size determination: Particle analysis was performed with an aerodynamic particle sizer with laser velocimeter (TSI-APS 3300)
- Treatment of exhaust air: outlet air was purified via a cotton wool filter
- Temperature, humidity, pressure in air chamber: temperature approx. 22 °C; relative air humidity approx. 30%


TEST ATMOSPHERE
- Brief description of analytical method used: Concentration in the test atmosphere was determined by gas chromatography (WL detector).
- Samples taken from breathing zone: yes


VEHICLE
- Composition of vehicle (if applicable):polyethylene glycol 400 (= PE) - ethanol mixture (mixing ration 1:1) for low concentrations
- Concentration of test material in vehicle (if applicable): approx. 10000 µL PE/m3 as an aerosol, approx. 10000 µL ethanol/m3 as a vapor)


TEST ATMOSPHERE (if not tabulated)
- Particle size distribution/MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): see any other information

Analytical verification of test atmosphere concentrations:

yes

Remarks:

Concentration in the test atmosphere was determined by gas chromatography (WL detector)

Duration of exposure:

>= 4 h

Concentrations:

nominal: 1000; 5000; 20000; 50000 mg/m3
analytical: 118.5; 586.4; 2007.6; 3550.7 mg/m3

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 2 weeks post-treatment observation period
- Frequency of observations and weighing: Clinical signs - several times on day of exposure
- twice daily (mornig evening)
Rectal temperature - directly after exposure was completed
Body weights - before exposure; day 3 and 7
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, rectal temperature, necropsy

Statistics:

yes, different methods (Fisher's Pairwise Test, Box Test, ANOVA method etc)

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 3 550.7 mg/m³ air (analytical)

Exp. duration:

4 h

Mortality:

No animals died up to and including a concentration of 20000 mg/m3 (nominal)
One male animal died on day 0 at a concentration of 50000 mg/m3 (nominal) all other animals survived the postobservation period

Clinical signs:

other: - 0mg/m3 and 1000mg/m3: All rats tolerated the treatment without clinical signs. - 5000mg/m3 Nose reddened, reduced motility, piloerection. All animals without signs from day 1 of the post-treatment observationperiod - 20000mg/m3 Rhinarium swollen, nose r

Body weight:

A toxicologically significant influence on body weights occurred during the post-treatment observation period from 20000 mg/m3 onwards.

Gross pathology:

Rats which died intercurrently; Lung distended, liver-like and edematous; hydrothorax; nose and rhinarium reddened and swollen; spleen pale; kidneys marbled; contents of duodenum slimy-yellow.
Rats sacrificed at the end of the post-treatment observation period; Gross pathological examination revealed no evidence of specific organ changes. In 50000µL/m3 "distended lung" tended to be more prevalent amongst the animals.

Other findings:

A toxicologically significant hypothermia was determined at the end of exposure from group 3 (5000 mg/m3 air)

ASSESSMENT AND DISCUSSION:

The test substance as an aerosol proved to have a relatively low acute inhalative toxicity in the rat up to the maximum tested concentration of 3551 mg/m3 air.

A single 4-hour exposure to 3551 mg/m3 air resulted in relatively persistent respiratory disorders considered to be causally related to a primary irritant effect on the respiratory tract. The hypothermia determined from 586.4 mg/m3 air is considered to be causally related to the aerosol's local irritant potential.

Interpretation of results:

not classified

Remarks:

Migrated information Acute inhaltion toxicity tested up to max attainable conc. Criteria used for interpretation of results: other: EU GHS EC 1272/2008

Conclusions:

LC50 inhalation (aerosol) Rat (exposure: 4 h) > 3551 mg/m3 air

Executive summary:

A study for acute inhalation toxicity was conducted with "confidential substance name" in accordance with OECD Guideline No. 403.

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; nebulization 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 inhalative toxic effect on 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

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

3 551 mg/m³ air

Quality of whole database:

The only availabel study is of good quality.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

see Discussion

Additional information

Valid data is available for the assessment of acute oral, acute dermal and acute inhalation toxicity of the registered substance.

Acute oral toxicity:

Studies according OECD guidelines:

The acute oral toxicity of the registered substance in rats was determined according to OECD Guideline 401 under GLP (Clariant 1993, Hoffmann). Therefore 2000mg/kg bw of the test substance was applied via gavage to five male and female wistar rats in a limit test. One female died in the 2000 mg/kg on application day. Additional to unspecific symptoms adverse effects on motion sequence, respiration and reflexes were observed. The animal showed also abdominal and letaral position, lid narrows, epiphora, reduced surface temperature and signs of stupor. On day 7 after application all surviving animals were free of symptoms. The body weight gain was not affected. In result a Dosis letalis media (LD50) above 2000mg/kg bodyweight can be drawn from the experiment. Necropsy of died animal shows liver colouring and lobular pattern and diffuse redness of the gastric mucosa. Necropsy of the survived animals reveals no macroscopic visible alteration.

Studies according to other guidelines

In another study the acute oral toxicity of the registered substance was evaluated in compliance with the conditions specified in the regulation for the enforcement of the Federal Insecticide, Fungicide, and Rodenticide Act (40 CFR), and the Toxic Substances Control Act (40 CFR) (Stepan 1998, J.J. Kreuzmann). Therefore female and male sprague dawley rats received 5.0 g/kg, 2.5 g/kg, 1.25 g/kg and 0.625 g/kg via gavage (five animals for the highest dosage and two animals per sex for all other dosages). At the dose level of 5.0 g/kg ten deaths occurred between days 0 and 1 of the observation period. At the dose level of 2.5 g/kg three deaths occurred between days 0 and 1 of the observation period. At the dose level of 1.25 g/kg one death occurred on day 2 of the observation period. At the dose level of 0.625 g/kg no deaths occurred during the observation period. The gross necropsy findings in the animals that died during the observation period were those generally seen in agonal animals. The acute oral LD was value was estimated to be 1.77 g/kg in male and female Sprague-Dawley rats.

According to the registrant, the study must be rated less of relevance as there were minor information missing in the report and the study was conducted according to a less suitable protocol , which is not perfect suitable to derive classification. If linear regression is used for calculation of LD50 a LD50 of 1875 -2344mg/kg can be calculated. The revised report calculates a LD 50 of 1770 mg/kg with 95% confidence limits of 1020 – 3080 mg/kg bw. As these calculated values are near to the classification limit and the study was not suitable to distinguish between 1800, 2000mg/kg and a better study is available the Registrant decides to rate this study lower in relevance and to refer to the more suitable conducted study.

 

 

Acute dermal toxicity:

A study for acute dermal toxicity in male and female rats was conducted with the registered substance under 24-hour occlusion conditions. The method used complied with the OECD - Guideline No. 402 and was performed under GLP (Bayer 1995, W. Bomann).Male wistar rats received doses of 50, 200, 2000 and 5000 mg/kg b.w. (male), while female wistar rats were treated with 50, 200, 400 and 2000 mg/kg b.w. via dermal application. Per dose, five rats were used. The results are summarized as follows:

LD50: rat (male): approx. 2000 mg/kg b.w.

rat (female): >400 - <2000 mg/kg b.w.

The main clinical signs observed were piloerection, decreased motility, decreased reactivity, poor or no reflexes, spastic gait and labored breathing. The clinical signs occurred 30 minutes after administration and were reversible within the post-treatment observation period. The no-effect level for the systemic effects was 200 mg/kg b.w..

The following main local effects were observed: reddening, dark color, incrustation, squamation and formation of scab. The skin effects lasted from day 2 until the end of the study. These local effects were observed for doses of 200 mg/kg b.w. resp. 0.6 mg/cm2 or higher. Linear interpolation of effects observed for 400 and 2000 mg/kg bw in females results in a LD 50 of approximately 800 mg/kg bw (important for GHS label).

In the dose range causing mortality in males reductions of body weights were observed fort he surviving rats, which were reversible by the end of the study. In animals which died during the observation period, a brownish- red content in the urinary bladder and discoloration of the liver was observed. At the end of the observation period no treatment-related gross findings were present. Accordingly, the test substance was of moderate acute dermal toxicity to female rats and of low toxicity to male rats..

In an acute dermal toxicity study (limit Test), according to OECD guideline 402, young adult Wistar rats (5 males and 5 females) were dermally exposed to a single dose of 2000 mg/kg bw of Octanamide, N,N-dimethyl- to the clipped skin (dorsal and dorso-lateral parts of the trunk) and covered by semi-occlusive dressing for 24 hours. The application area comprised at least 10% of the total body surface area. The animals were observed for 14 days.The following test item-related clinical observations were recorded during the course of the study:

No mortality occurred, Impaired general state in seven animals, Poor general state in one animal,

Dyspnoea in six animals, Piloerection in six animals, Exsiccosis in two animals,Exophthalmos in one animal, Lacrimation in one animal, Lateral position in one animal and Diarrhea in one animal.

The following test item-related local effects were recorded during the course of the study: Slight to well-defined erythema (grade 1 to 2)

The mean body weights of the male and female animals increased as expected in four animals in each group but distinctly decreased in one male and female animal during the observation period. Macroscopic pathological findings in the animals examined on the last day of observation (findings in the male and female animal, which showed weight reduction):

o Dark red discoloration of the liver

o No content in stomach

o Red discoloration of the glandular stomach

o Red discoloration of the small intestine and its content

There were no macroscopic pathological findings in the other 4 males and females. Accordingly, the acute dermal median lethal dose (LD₅₀) was determined to be LD₅₀, dermal, rat > 2000 mg/kg bw.

In addition, an acute dermal toxicity according OECD Guideline No. 402 of N,N-dimethyldecanamid is available. 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. Piloerections was the only clinical sign and post mortem inspection revealed no abnormalities. The dermal LD50 of N,N-dimethyldecanamidin rats was found to be above 5000 mg/kg bw.

In summary, the two main ingredients of the registered substance - N,N-dimethyloctanamid and N,N-dimethyldecanamid – did not cause any mortality for any sex in acute dermal toxicity test with LD50 of > 2000 mg/kg b wand > 5000 mg/kg bw, respectively. In contrast, the registered substance resulted in mortality in male and females with LD50 of approximatley 2000 mg/kg b wand of > 400, but < 2000 mg/kg bw. There are no obvious reasons from the studies that could explain this difference. Considering the available information in an weight-of-evidence appraoch, it is concluded that the LD50 of the registered substance for both male and females is > 2000 mg/kg bw.

For acute dermal toxicity there are three studies available. One with the registered and one for each of the main constituents. These three studies were considered in a weight-of-evidence approach.

Acute inhalation toxicity:

A study for acute inhalation toxicity was conducted with the registered substance 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 inhalation toxicity, this study has been used as key study.

For acute oral toxicity there are two studies available with a comparable mixture. 

According to the registrant, the study from Stepan (Stepan 1998, J.J. Kreuzmann) must be rated less of relevance as there were minor information missing in the report and the study was conducted according to a less suitable protocol, which is not perfect suitable to derive classification. Linear regression results vary if the LD50 is calculated based on results of this studies depending on the calculation method and confidence limits used. In result an LD 50 near to the classification limit could be derived and as the study was not suitable to distinguish between 1800, 2000mg/kg and a better study is available the Registrant decides to rate this study lower in relevance and to refer to the more suitable conducted study (Clariant 1993, Hoffmann) to decide about acute oral toxicity.

For acute dermal toxicity there are three studies available. One with the registered and one for each of the main constituents. These three studies were considered in a weight-of-evidence approach.

Justification for selection of acute toxicity – oral endpoint

The most reliable study was selected as key study.

Justification for selection of acute toxicity – inhalation endpoint

The only available (and reliable) study was selected.

Justification for selection of acute toxicity – dermal endpoint

The three available and relevant studies of the registered substance (Bayer 1995, Bomann ) and iis two main constituents (BASF SE 2012; Cognis 1997, Hoyer) were evaluated in a weight of evidence appraoch.

Justification for classification or non-classification

The available data for the regsitered substance as well as for the main two constituents indicate a low potential for acute toxicity.

The available study indicates an oral LD50> 2000 mg/kg bw (Clariant 1993, Hoffmann) for male and female rats. Therefore the registered substance does not need to be classified for acute oral toxicity according to GHS (Regulation (EU) 1272/2008) and also according to EU-criteria DSD (67/548/EEC).

Evaluating the three available and relevant acute dermal toxicity studies of the registered substance (Bayer 1995, Bomann ) and ist two main constituents in a weight of evidence appraoch (BASF SE 2012; Cognis 1997, Hoyer), its LD50 (rat) for acute dermal toxicity is considered to be above 2000 mg/kg bw for male rats and female rats. Consequently, the registered substance has not to be classified as acute dermal toxic according to GHS (Regulation (EU) 1272/2008) and EU-criteria DSD (67/548/EEC).

As an acute inhalation toxicity test with the registered substance revealed 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 registered substance does not need to be classified for acute inhalation toxicity according to GHS (Regulation (EU) 1272/2008) and EU-criteria DSD (67/548/EEC).

Derived labelling for acute oral, dermal toxicity and inhalation toxicity (N,N-dimethyloctanamide):

GHS: no classification

DSD: no classification