2-morpholinoethanesulphonic acid

Endpoint summary

Description of key information

In a GLP-study according to OECD TG 423 (acute class method) with rats, the LD50 of the substance was determined as > 2000 mg/kg bw (reference 7.2.1 -1). The study was performed with the hydrate form of the substance (CAS 1266615-59-1). However, same results are expected for the anhydrous form (CAS 4432-31-9).

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

Study period:

2016-10-4 to 2016-10-20

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

2001

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Version / remarks:

2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Version / remarks:

2002

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Remarks:

Crl:WI

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: TOXI COOP ZRT. Cserkesz u. 90., 1103 Budapest, Hungary
- Females nulliparous and non-pregnant: yes
- Age at study initiation: 8 weeks
- Weight at study initiation: 187 - 192 g (1st step), 185-190 g (2nd step)
- Fasting period before study: 1 day
- Housing: group caging (3 rats/cage), Type II polypropylene/polycarbonate
- Diet: ad libitum, ssniff® SM R/M-Z+H complete diet for rats and mice
- Water: ad libitum, tap water
- Acclimation period: 5-6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22+/-3 °C
- Humidity (%): 30 - 70%
- Air changes (per hr): approx. 10/h
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/mL
- Amount of vehicle: 10 mL/kg bw
- Justification for choice of vehicle: standard vehicle
- Purity: aqua purificata Ph.Hg. VIII. from Parma Produkt Kft. (Batch no. 1606-5508)

MAXIMUM DOSE VOLUME APPLIED: 10 mL

CLASS METHOD
- Rationale for the selection of the starting dose: Selection was based on the basis of the available information about the test item and similar substances.

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

6 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: rats were observed at least once daily and weighted on days 0, 7 and 15
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, appearance of tissue and organs
- experimental design: the study was performed in two consecutive steps with three rats per step.

Statistics:

not applicable

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

none

Clinical signs:

other: none

Gross pathology:

moderate to severe hydrometra, a physiological finding related to the cycle of the rats, was observed in two rats

Interpretation of results:

GHS criteria not met

Conclusions:

The LD50 value of the test substance is considered to be >2000 mg/kg bw.

Executive summary:

The acute oral toxicity of the substance was investigated in a GLP study according to OECD TG 423. The study was conducted in two consecutive steps with three rats per step. All six female rats treated with 2000 mg/kg bw by oral gavage survived the observation period. No signs of toxicity were detected. The body weight development was normal. Gross pathology showed no test substance related alterations. The LD50 value of the test substance is considered to be >2000 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Quality of whole database:

OECD TG 423, GLP

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because exposure of humans via inhalation is not likely taking into account the vapour pressure of the substance and/or the possibility of exposure to aerosols, particles or droplets of an inhalable size

Justification for type of information:

According to (EC) No 1907/2006, Annex VIII, 8.5, column 2, at least one other route for substances shall be tested for acute toxicity in addition to the oral route. However, due to the estimated very low vapour pressure (1.39e-4 Pa) of the substance, exposure of humans via inhalation of vapours is unlikely. No adverse effects have been observed (i) in an acute oral toxicity study at a limit dose of 2000 mg/kg bw and (ii) in a combined repeated dose up to the highest dose tested. Therefore, although the test material is a solid powder and exposure to dusts are possible, no adverse effects are expected and no additional study on acute inhalation toxicity was performed.

Clinical signs:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance does not meet the criteria for classification as acute toxicity or STOT SE by the oral route and no systemic effects have been observed in in vivo studies with dermal exposure (e.g. skin irritation, skin sensitisation)

Justification for type of information:

According to (EC) No 1907/2006, Annex VIII, 8.5, column 2, at least one other route for substances shall be tested for acute toxicity in addition to the oral route. Since dermal absorption will be very low and no effects have been reported in an in vivo skin sensitisation study, a study on acute dermal toxicity was waived.

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Acute oral

The acute oral toxicity of the substance was investigated in a GLP study according to OECD TG 423. The study was conducted in two consecutive steps with three rats per step. All six female rats treated with 2000 mg/kg bw by oral gavage survived the observation period. No signs of toxicity were detected. The body weight development was normal. Gross pathology showed no test substance related alterations. The LD50 value of the test substance is considered to be >2000 mg/kg bw. The study was performed with the hydrate form of the substance (CAS 1266615-59-1). However, same results are expected for the anhydrous form (CAS 4432-31-9).

Justification for classification or non-classification

Classification, Labeling, and Packaging Regulation (EC) No 1272/2008

The available data for acute oral toxicity are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. Based on this data, the substance is not considered to be classified for acute oral toxicity under Regulation (EC) No 1272/2008, as amended for the fifteenth time in Regulation (EU) 2020/1182.