Quaternary ammonium compounds, di-C12-18-alkyldimethyl, chlorides

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

From 21 February, 1990 to 30 April, 1990

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

However, tested substance was a mixture of two different quaternary ammonium compounds containing products with conflicting and partially unknown identity.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPP 81-3 (Acute inhalation toxicity)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Quaternary ammonium compounds, benzyl C12-C16 (even numbered)-alkyldimethyl chlorides

EC Number:

939-253-5

Molecular formula:

C12-14H25-29-(CH3)2-C6H5-N.CL

IUPAC Name:

Quaternary ammonium compounds, benzyl C12-C16 (even numbered)-alkyldimethyl chlorides

Constituent 2

Reference substance name:

Quaternary ammonium compounds, di-C12-18-alkyldimethyl, chlorides

EC Number:

269-924-1

EC Name:

Quaternary ammonium compounds, di-C12-18-alkyldimethyl, chlorides

Cas Number:

68391-05-9

Molecular formula:

Substance is an UVCB (representative molecular formula for 2 major constituents: C12-C12 DAQ: C26H56Cl1N1; C18-C18 DAQ: C38H80Cl1N1)

IUPAC Name:

N-C12-C18(even numbered)-alkyl-N,N-dimethyl-C12-C18(even numbered)-alkyl-1-aminium chloride

additive 1

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

water

Test material form:

not specified

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River UK Ltd., Margate, UK
- Weight at study initiation: ca. 200 g on the d of exposure
- Housing: 5/sex in polypropylene cages with detachable wire mesh tops and floors
- Diet (e.g. ad libitum): ad lib
- Water (e.g. ad libitum): ad lib
- Acclimation period: at least 5 d

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-24
- Humidity (%): 35-65

IN-LIFE DATES: From 21 February, 1990 to 30 April, 1990

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: perspex whole body chamber (square section with pyramidal top)
- Exposure chamber volume: ca. 120 L
- Method of holding animals in test chamber: wire mesh partitions to provide 10 separate animal compartments
- Source and rate of air: filtered and oil-free compressed air
- Method of conditioning air: dried
- System of generating particulates/aerosols: atomiser
- Method of particle size determination: cascade impaction (Andersen mini-sampler and Marple cascade impactor (model 296)
- Treatment of exhaust air: passage through a collection filter
- Temperature, humidity, pressure in air chamber: temperature measured at 30-min intervals (22-23°C), relative humidity not measured (reason: aqueous solution). However, as dried air was used and the test substance contained only 7.7% water, relative humidity could have been measured. Pressure in air chamber: not indicated. However, as the whole body chamber was placed in a hood, this is not as important.

TEST ATMOSPHERE
- Brief description of analytical method used:
Five air samples (5 L for groups 2 and 4 (0.34 and 0.24 mg/L), 10 L for group 3 (0.17 mg/L) were taken from the chamber during each exposure and the collected material was analysed to determine the concentration of QAC mixture in the chamber air. Each air sample was withdrawn, at 4 L per min, through a weighed glass fibre filter (Whatman GF/A) mounted in an open face filter holder. The volume of the air sample was measured with a wet-type gas meter. Two further air samples were taken using an Andersen mini-sampler or a series 290 Marple cascade impactor (Model 296), and the collected material was weighed to determine the particle size distribution of QAC mixture. The samples were taken at approximately 1.5 and 3.5 h from the start of exposure. The filters from the open face sampler were transferred to extraction columns and compacted with a glass road. The QAC mixture was eluted with five 2 mL portions of methanol into a 20 mL volumetric flask and diluted to volume with methanol.
The filters from the Andersen and Marple samplers were similarly treated t o give a final volume of 5 mL. The stages of the Andersenand Marple samplers were washed off with small amounts of methanol into 5 mL volurnentric flasks. The extracts were diluted with mobile phase to obtain solutions for HPLC-analysis with expected maximum concentrations of QAC mixture of 150 pg/mL.

- Samples taken from breathing zone: taken from the whole body chamber.

VEHICLE: not used

TEST ATMOSPHERE (if not tabulated)
Concentrations:
0.34 mg/L (± 6%); nominal: 2.21 mg/L
0.17 mg/L (± 13%); nominal: 0.52 mg/L
0.24 mg/L (± 17%); nominal: 0.88 mg/L

- MMAD (mass median aerodynamic diameter) / GSD (geometric standard deviation):
0.34 mg/L : MMAD 1.9 µm, gsd 3.5
0.17 mg/L : MMAD 1.1 µm, gsd 2.7
0.24 mg/L : MMAD 0.8 µm, gsd 1.5

Analytical verification of test atmosphere concentrations:

yes

Remarks:

HPLC

Duration of exposure:

ca. 4 h

Concentrations:

0 (group 1), 0.17 (group 2), 0.24 (group 3) and 0.34 mg/L (group 4)

No. of animals per sex per dose:

5 per sex per concentration

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 21 d
- Frequency of observations and weighing: observations continuously duringe exposure and at least twice daily thereafter; BW daily
- Food and water intake: daily
- Necropsy of survivors performed: yes
- Other examinations performed: lung weight, histopathology of lungs, liver and kidneys

Statistics:

LC50 determination by log probit method of Miller LC and Tainter ML, Proc. Soc. Exp. Bio. Med., 57(2),1944:261-264.

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

male

Dose descriptor:

LC50

Effect level:

ca. 220 mg/m³ air (analytical)

95% CL:

ca. 170 - ca. 270

Exp. duration:

4 h

Remarks on result:

other: equivalent to 170 mg QAC/m3 (130- 210)

Effect levels 2

Key result

Sex:

female

Dose descriptor:

LC50

Effect level:

ca. 280 mg/m³ air (analytical)

95% CL:

ca. 210 - ca. 350

Exp. duration:

4 h

Remarks on result:

other: equivalent to 220 mg QAC/m3 (160 - 270)

Effect levels 3

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

ca. 250 mg/m³ air (analytical)

95% CL:

ca. 220 - ca. 280

Exp. duration:

4 h

Remarks on result:

other: equivalent to 190 mg QAC/m3 (170 - 220)

Mortality:

control group: 0/10
0.17 mg/L: 1 male (1/10)
0.24 mg/L: 3 males and 1 female (4/10)
0.34 mg/L: 5 males and 4 females (9/10)

Clinical signs:

other: During exposure The signs seen during exposure were considered to be consistent with inhalation of an irritant aerosol. Closing or partial closing of the eyes and exaggerated respiratory movement were seen in all rats exposed to QAC mixture.

Body weight:

The female rat surviving exposure at 0.34 mg/L (Group 2) failed to gain weight normally for 14 days following exposure. There were moderate to marked decreases of bodyweight or reductions in the rate of bodyweight gain for up to 8 days in male rats and for up to 14 days in female rats following exposure at 0.17 mg/L or 0.24 mg/L of air. Subsequently weight gain for rats that survived exposure to QAC mixture was similar to that of the control rats.

Gross pathology:

The findings for rats that died as a result of exposure to QAC mixture were typified by congestion of the lungs, fluid in the trachea and gas-filled stomach. Macroscopic abnormalities in a proportion of rats that survived exposure to QAC mixture were a swollen appearance of the lungs and gas-filled stomachs and intestines.

Other findings:

The food and water consumption for the rat that survived exposure at 0.34 mg/L was variable and reduced. Food consumption was reduced for up to 12 d following exposure to QAC mixture at concentrations of 0.24 or 0.17 mg/L. The water consumption for these groups was reduced for up to 14 d following exposure.

The lung weight to body weight ratio was increased, due to a high lung weight, for most rats that died as a result of exposure to QAC mixture for a few decedents and the majority of the surviving rats was increased because of low body weight.

Histopathology
Group 2 (0.34 mg/L QAC mixture)

Decedents
Treatment-related changes were seen in the 5 male and 4 female decedents. The distribution of these lesions was as follows: focal alveolar wall necrosis in 3 males; diffuse congestion in 3 males and 4 females; eosinophilic material in alveoli in 5 males and 4 females; alveolitis in 2 males and 4 females; focal alveolar oedema in 1 male; perivascular oedema in 4 males.

Survivors
Treatment-related changes were seen in the single female rat surviving to the end of the observation period. These were as
follows: focal alveolitis; focal bronchiolitis; prominent bronchiolar goblet cells.

Group 3 (0.17 mg/L QAC mixture)
Decedents
Treatment-related changes were seen in the single decedent male. These were as follows: diffuse congestion; eosinophilic materialin alveoli; alveolitis; focal alveolar oedema.

Survivors
Treatment-related changes were seen in one of the 4 males and in one of the 5 females surviving to the end of the observation period. The distribution of these lesions was as follows: focal bronchiolitis in 1male; prominent bronchiolar goblet cells in 1 male; foreign body giant cells in 1 male; focal alveolar haemorrhage in 1 female. A focus of emphysema was also seen in one surviving female. The significance of this finding in a single animal is unclear, but possibility that it is related to treatment cannot be excluded. No abnormalities were detected in 3 males and 3 females surviving to the end of the observation period.

Group 4 (0.24 mg/L QAC mixture)
Decedents
Treatment-related changes were seen in the 3 male decedents and 1 female decedent. The distribution of these lesions was as follows: diffuse or focal congestion in 2 males and 1 female; eosinophilic material in alveoli in 2 males and 1 female; alveolitis in 1 male and 1 female; focal alveolar oedema in 1 male; focal alveolar haemorrhage in 1 female; perivascular oedema in 1 female.

Survivors
Treatment-related change was seen in one of the two males and one of the 4 females surviving to the end of the observation period. This lesion was: foreign body giant cells. No abnormalities were detected in 1 male and 3 females surviving to the end of theobservation period.

Comment from the authors
Treatment-related changes were found in the survivors from all groups. It is not possible to predict with certainty the progression of these lesions, but the changes were minimal and of a focal nature and it is possible that they would be resolved in the course of time leaving no permanent lesions.

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

Under the study conditions, the 4 h LC50 of the QAC mixture was found to be 250 mg/m3 (equivalent to 190 mg QAC/m3), when tested at an MMAD ≤ 1µm.

Executive summary:

A study was performed to determine the acute toxicity of a mixture of two quaternary ammonium compounds (QAC) (77.3% QAC active) following inhalation exposure to the rats, according to the OECD Guideline 403 and EPA Guideline 81-3, in compliance with GLP. The mixture consisted of 77.3% w/v QAC: (a) cocobenzyl dimethyl ammonium chloride (CAS no. 68424-85-1; EC no. 270-325-2): 40% w/v (b) dicoco dimethyl ammonium chloride (CAS no. 8001-54-3; EC no. 263-087-6): 37.5% w/v. Four groups of ten rats each (five males and five females) were given a single, 4 -h whole body exposure at three concentration levels with a MMAD (mass median aerodynamic diameter) / GSD (geometric standard deviation): (TG403 indicates a preferable MMAD of 1 -4µm with gsd 1.5 -3) (a) 340 mg/m3 : MMAD 1.9 µm, gsd 3.5 (b) 170 mg/m3 : MMAD 1.1 µm, gsd 2.7 (c) 240 mg/m3 : MMAD 0.8 µm, gsd 1.5. The animals were observed for 21 d after exposure and were then killed for gross and histopathological examination of the lungs. Body weight, food and water intake and lung weight were also determined. There were no deaths in the control group; one animal (male) died at 170 mg/m3, four animals died at 240 mg/m3 (3 males, 1 female), and nine animals died at 340 mg/m3 (5 males, 4 females). Clinical signs observed during exposure are consistent with inhalation of an irritant substance and included (partial) closing of the eyes and exaggerated respiratory movement during exposure in all test groups, gasping and wetness around the mouth during exposure at 340 mg/m3. Clinical signs were noted in survivors throughout the 21 -d observation period. Decrease of body weight, reduced weight gain, and reduced food and water intake was generally seen up to 14 day. Abnormalities noted at necropsy in survivors were increased relative lung weight, swollen appearance of the lungs and gas-filled stomach and intestines. Animals that died showed congestion of the lungs, fluid in the trachea, and gas-filled stomach. Histopathological lung changes in survivors generally consisted of focal alveolitis and bronchiolitis; changes in deceased animals generally consisted of focal alveolar wall necrosis, diffuse congestion, focal alveolar wall oedema and focal alveolar wallhaemorrhage. The acute 4-h LC50 value of the test substance was found to be 250 mg/m3 (220 -280 mg/m3) [equivalent to 190 mg QAC/m3 (170 - 220)]. The study results clearly fit the pulmunary exposure of a corrosive substance deep in the lungs (MMAD < 1 µm) resulting to local damage. Immediately at the start of the exposure all the animals of the 0.24 and 340 mg/m3 groups showed exaggerated respiratory movements and partially closed eyes. After 15 minutes also all animals of the 170 mg/m3 group showed these effects. The exposures damaged alveolar and bronchiolar walls leading to pulmonary oedema and subsequent death. Under the study conditions, the 4 h LC50 of the QAC mixture was found to be 250 mg/m3 (equivalent to 190 mg QAC/m3), when tested at an MMAD ≤ 1µm (Jackson, 1980).