Sodium 2,4-dichlorophenoxyacetate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

17 Jun 1998 - 01 Jul 1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP - Guideline study, tested with the source substance Dimethylammonium 2,4-dichlorophenoxyacetate (CAS No. 2008-39-1). In accordance to the ECHA guidance document “Practical guide 6: How to report read-across and categories (March 2010)”, the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

yes

Remarks:

, limited data on test atmosphere

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.2 (Acute Toxicity (Inhalation))

Deviations:

yes

Remarks:

, limited data on test atmosphere

GLP compliance:

no

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dimethylammonium 2,4-dichlorophenoxyacetate

EC Number:

217-915-8

EC Name:

Dimethylammonium 2,4-dichlorophenoxyacetate

Cas Number:

2008-39-1

IUPAC Name:

N-methylmethanaminium (2,4-dichlorophenoxy)acetate

Details on test material:

- Name of test material (as cited in study report): Aminopielik 600 SL
- Physical state: brown liquid
- Analytical purity: 606 g/L
- Impurities (identity and concentrations):
chlorphenol. 0.16%
- Storage condition of test material: test substance was kept at temperature of 20 - 25 °C
- Other:
pH = 7 - 9
boiling point = about 100 °C
flash point = > 100 °C
d= 1.19 - 1.23 g/cm3

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 3 months
- Weight at study initiation: 190 - 245 g (males), 201 - 213 g (females)
- Housing: suspended stainless steel wire mesh, 5 animals per cage
- Diet: "Murigran" standard diet ad libitum
- Water: ad libitum
- Acclimation period: at least 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.5 - 22.5
- Humidity (%): 50 - 65
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

whole body

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: chamber made of stainless-steel and glass
- Exposure chamber volume: 0.06 m³
- Source and rate of air: 17 L/min (17 air changes/h)
- System of generating particulates/aerosols: atomizer

TEST ATMOSPHERE
- Brief description of analytical method used:
The concentration of Aminopielik 600 SL was measured at least once an hour using a spectrophotometric method. The light absorbance was measured at wavelength 263 nm with a control sample as reference.
Taking air samples: 5 L of test air was being passed through a filter and flask containing 2 cm3 of ethanol.

- Rationale for the selection of the starting concentration:
Based on the data indicating low toxicity to animals after oral exposure (LD50 = 911 mg/kg for rats), the study was conducted with
Aminopielik 600 SL at concentrations close to the limit value (5 mg/L).

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

5377 mg/m³ air ± 1352 (females)
5083 mg/m³ air ± 1422 (males)

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 15 days
- Frequency of observations and weighing:
The animals were observed during exposure, once after exposure on the test day 1 and then once daily after exposure. The nature of the toxicity as well as the onset, the intensity and the duration of the signs were recorded.
Mortality was checked twice daily, on weekend only once daily. Time of death and number of dead animals per dose were documented
Body weights were recorded at the beginning and at the end of the study, or after death of the animals
- Necropsy of survivors performed: yes
- Other examinations performed: external appearance of all internal organs, histopathology

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

>= 5 000 mg/m³ air

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: 2 male and 1 female animal died

Mortality:

3 Male and 4 female animals survived the exposure to the test substance. The deaths of one male and one female animal was recorded on day 1 after exposure, another male animal died on day 2.

Clinical signs:

other: The animals in the test substance-exposed groups exhibited abnormalities during the exposures. Generally, they showed signs of laboured or irregular breathing and body convulsions. Upon removal from the chamber most of the animals continued to exhibit la

Body weight:

Mean body weight of males decreased slightly during the first week and increased during the second week of observation.
Mean body weight of females decreased slightly during the second week of observation.

Gross pathology:

Examinations revealed no pathological changes.

Other findings:

- Other observations:
Mean water and food consumption of males increased during the second week.
Mean water and food consumption of females was similar during both weeks.

Any other information on results incl. tables

concentration (mg/m3)	Mortality per group (animals)
	Females	Males
5083	1
5377		2

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU