Reaction mass of sodium 4-hydroxybenzenesulfonate and disodium 4-hydroxybenzene-1,3-disulfonate and sodium sulfate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Literature data

Data source

Reference

Reference Type:

publication

Title:

Inhalation Toxicology of Sodium Sulfite Aerosol in Rats.

Author:

Last, J.A. Purnendu, K.D., Ethinson, J.R.

Year:

1980

Bibliographic source:

Toxicol. Appl. Pharmacol. 55:229-234.

Materials and methods

Principles of method if other than guideline:

Non-standard protocol: rats were exposed to well-characterized aerosols of sodium sulphate. The responses of rats to breathing these aerosols for 3 days were evaluated by measurements of glycoprotein secretion rates by cultured tracheal explants from these rats, by measurement of protein.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Sodium sulphate

EC Number:

231-820-9

EC Name:

Sodium sulphate

Cas Number:

7757-82-6

Molecular formula:

H2O4S.2Na

IUPAC Name:

Disodium sulfate

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Portage, Michigan
- Age at study initiation: 70-80 days old
- Healtly: animals were certified by the supplier to be chronic respiratory disease free.

Administration / exposure

Route of administration:

inhalation: aerosol

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: were in Hinners-type stainless-steel chambers
- Method of holding animals in test chamber:daily cleaning of cages and restocking of feed and water.

TEST ATMOSPHERE
- Aerosol: generated as dry particles at 50% relative humidity and monitored by wet chemical procedures (West-Gaeke technique) and by ion chromatography.
- Aerosol generation: aerosol was generated either with Babington (1- 15 mg/m3) or Retec (0.1 mg/m3) nebulizers
- MMAD (Mass median aerodynamic diameter):between 0.83 and 1.15 μm; σg ranged from 1.9 to 2.9.

Duration of exposure:

ca. 3 d

Remarks on duration:

for 23.5 hr per day

Concentrations:

10 mg/m3 nominal concentration (10.0 ± 0.2 mg/m3 actual concentration)

No. of animals per sex per dose:

6

Details on study design:

- Necropsy of survivors performed: yes; Rats were killed within an hour of the termination of exposure by exsanguination after pentobarbital injection (75 mg/kg, intraperitoneally).
- Other examinations performed:

After thoracotomy, lungs were perfused in situ via the pulmonary artery by injection of isotonic saline into the right ventricle, with drainage from the subclavian artery. One lobe of the lung was clamped with a hemostat prior to perfusion to allow for subsequent determination of water content after removal, weighing, and drying for about 24-48 hr at 110 to 120°C.
The remaining perfused lobes of the lungs were removed, washed, and homogenized.
Tracheae from the same rats were removed, washed, sliced, and incubated as described in detail elsewhere.

Results and discussion

Effect levels

Sex:

male

Dose descriptor:

other: LOEC

Effect level:

> 10 mg/m³ air (nominal)

Based on:

test mat.

Exp. duration:

3 d

Mortality:

No mortality occurred

Clinical signs:

other: MMAD: 1.15 μm and σg = 2.5%

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

LOEC > 10 mg/m3

Executive summary:

Rats were exposed to 10 mg/m3 of Na2SO4 as a dry particle aerosol in air with 50% humidity (particle size 1.15 μm Mean Mass Aerodynamic Diameter;, σg = 2.5) for 72 hours. These six male rats served as negative controls for rats exposed to various concentrations of sodium sulfite and sodium hydroxymethane sulfonate.

Result

Clinical effects were not reported. Compared to the filtered-air control group, no significant changes in various inflammation-related lung tissue parameters, determined post-mortem, were found (DNA, RNA, protein, wet-to-dry weight ratio, glycoprotein secretion in trachea explants).

LOEC > 10 mg/m3