Zinc sulphate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not applicable

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

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

Data source

Reference

Reference Type:

publication

Title:

Effects of brief and intermediate exposures to sulfate submicron aerosols and sulfate injections on cardiopulmonary function of dogs and tracheal mucous velocity of sheep

Author:

Sackner M A, Dougherty R L, Chapman G A, Cipley J, Perez D, Kwoka M, Reinhart M, Brito M and Schreck R

Year:

1981

Bibliographic source:

J Toxicol Environ Health 7:951-972

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Determination of pulmonary mechanics and hemodynamics in anesthetized dogs following breathing of Zinc sulphate as submicron aerosols.

GLP compliance:

no

Test type:

other: Cardiopulmonary study

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Zinc sulphate

EC Number:

231-793-3

EC Name:

Zinc sulphate

Cas Number:

7733-02-0

Molecular formula:

H2O4S.Zn

IUPAC Name:

zinc sulfate

Details on test material:

- Name of test material: Zinc sulphate
- Substance type: Pure active substance
- Physical state: Submicron aerosol

Test animals

Species:

dog

Strain:

other: Mongrel

Sex:

male/female

Details on test animals or test system and environmental conditions:

No data

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

other: Cuffed 8.5 French orotracheal tube

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: D-30 nebulizer system
- Exposure chamber volume: No data
- Method of holding animals in test chamber: Anesthetized with i.v. Sodium pentobarbital, 30 mg/kg of body weight, and placed in lateral position
- Source and rate of air: No data
- Method of conditioning air: No data
- System of generating particulates/aerosols: Aerosols were generated from solutions of reagent grade chemicals by using a D-30 nebulizer system. Droplets were dried to a relative humidity of 20-30 % by mixing with dry air, and their electrical charges were neutralized by an ionizing radiation source of Kr-85.
- Method of particle size determination: Measured with an Electrical Aerosol Analyzer (EAA) (Thermo Systems, Inc., St. Paul, Minn.)
- Treatment of exhaust air: No data
- Relative humidity: 20-30 %


TEST ATMOSPHERE
- Brief description of analytical method used: Aerosol concentrations were measured by a piezoelectric microbalance. The filters were 0.2 µm pore size Nucleopore filters, 47 mm in diameter, supported in a Gelman stainless steel holder. The volume of air sampled was measured by a wet-gas test meter downstream of the filter. Zinc sulphate concentrations were measured by a barium-perchlorate-thorin spectrophotometric titration method.
- Samples taken from breathing zone: No



TEST ATMOSPHERE
- Particle size distribution: 0.01-1 µm
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): No data

Analytical verification of test atmosphere concentrations:

yes

Remarks:

Barium-perchlorate-thorin spectrophotometric titration method

Duration of exposure:

7.5 - 240 min

Remarks on duration:

0.1 and 1% concentrations for 7.5 min; 0.5% concentration for 240 min

Concentrations:

0.1 % & 1 % for brief exposure study
0.5 % for intermediate exposure study

No. of animals per sex per dose:

Five

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 3 h
- Frequency of observations:

- Brief exposure study:
In the first series of experiments, groups of five dogs breathed for 7.5 min aerosols generated from 0.1 % solutions of Zinc sulphate. Measurements of lung volume and mechanics were obtained before and at 5, 15, 30, 60, 120, and 180 min after termination of the aerosol exposure. After completion of these measurements, the animals breathed aerosols generated from 1 % solutions of these salts for 7.5 min. Measurements of lung mechanics were repeated 5, 15, and 30 min after termination of the second exposures.
In the second set of experiments exposures to aerosols generated from 0.1 % salt solutions were omitted, and only 7.5-min exposures to aerosols generated from 1 % solutions. Measurements of total respiratory resistance, static lung compliance, and functional residual capacity were performed before and at 5, 15, 30, 60, 120, and 180 min after aerosol exposure.

- Intermediate Exposure study:
Groups of five dogs breathed for 4 h aerosols generated from 0.5 % solutions of Zinc sulphate. In addition, a 0.5% mixture of equal parts of the sulfate salts was employed. Measurements of lung volume, breathing mechanics, and hemodynamics were made before, hourly during, and for 2 h after completion of the aerosol exposures.
- Necropsy of survivors performed: No
- Other examinations performed: Measurements of lung volume, total respiratory resistance, static lung compliance, and functional residual capacity, breathing mechanics and hemodynamics.

Statistics:

Analysis of variance was performed according to the model of Lorenzen (1977)

Results and discussion

Preliminary study:

Not applicable

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

other: Effect on cardiopulmonary and hemodynamic mechanics

Effect level:

15.8 mg/m³ air (analytical)

Exp. duration:

7.5 min

Effect levels 2

Sex:

male/female

Dose descriptor:

other: Effect on cardiopulmonary and hemodynamic mechanics

Effect level:

8.3 mg/m³ air (analytical)

Exp. duration:

4 h

Mortality:

No data

Clinical signs:

other: No significant alterations in total respiratory resistance, static lung compliance, functional residual capacity, specific total respiratory conductance, and specific lung compliance after breathing for 7.5 min aerosols from 0.1 and 1.0 % solutions of Zin

Body weight:

No data

Gross pathology:

No data

Other findings:

No data

Any other information on results incl. tables

Table 1. Effects of Zinc sulfate aerosol (0.5 % for 4 h followed by 2 h observation) of pulmonary function of anesthetized dog ^a

 

Time (h)	RRS (cm H2O/L.s)	FRC (L/BTPS)	CL (L/cmH2O)	SCL (L/cm H2O.L)	SGRS (L/s.cmH2O.L)
Baseline +1 +2 +3 +4 +5 +6	1.7 (0.05) 1.8 (0.06) 2.0 (0.02) 1.9 (0.07) 2.0 (0.2) 1.8 (0.0l) 2.0 (0.1)	0.48 (0.05) 0.50 0.03) 0.47 (0.05) 0.47 (0.04) 0.47 (0.05) 0.47(0.04) 0.48 (0.05)	0.14 (0.02) 0.13 (0.01) 0.12 (0.01) 0.12 (0.009) 0.12 (0.02) 0.13 (0.02) 0.13 (0.02)	0.32 (0.08) 0.26 (0.03) 0.30 (0.07) 0.28 (0.05) 0.29 (0.07) 0.30 (0.07) 0.30 (0.09)	1.3 (0.2) 1.1 (0.08) 1.2 (0.2) 1.2 (0.2) 1.2 (0.2) 1.2 (0.1) 1.1 (0.1)

 

Table 2. Effects of Zinc sulfate aerosol (0.5 % for 4 h followed by 2 h observation) on hemodynamics and arterial blood gases of anesthetized dogs ^a

Time (h)	PPA (mm Hg)	PSA (mm Hg)	QP (L/min)	HR (beats/min)	SV (mL)	pH	pO2 (mm Hg)	pCO2 (mm Hg)
Baseline +1 +2 +3 +4 +5 +6	10.5 (0.3) 11.9 (1.4) 12.2 (0.03) 12.5 (0.5) 13.8 (1.1) 11.6 (0.8) 11.9(1.5)	104 (2) 96 (5) 106 (5) 116 (4) 108 (0) 106 (1) 106 (1)	2.78 (0.14) 2.99 (0.22) 2.80 (0.20) 2.93 (0.29) 2.49 (0.18) 2.56 (0.16) 3.06 (0.32)	142 (8) 131 (9) 144 (13) 117 (10) 122 (7) 124 (5) 127 (6)	20.1 (2.0) 21.6 (0.8) 20.7 (2.1) 24.4 (1.9) 20.9(1.4) 20.4 (0.8) 23.9 (1.9)	7.50 (0.03) 7.46 (0.02) 7.47 (0.02) 7.48 (0.02) 7.51 (0.01) 7.51 (0.02) 7.49 (0.02)	111 (5) 99.4 (4.3) 98.0 (6.6) 94.6 (5.3) 97.0 (6.5) 100 (6) 97.2 (3.5)	22.6 (13) 30.0 (0.9) 29.7 (0.23) 28.6 (1.1) 28.1 (0.8) 25.1 (1.5) 27.4 (3.0)

^aValues are mean (SE).

PPA= mean pulmonary arterial pressure; PSA= mean systemic arterial pressure; OP=cardiac output; HR= heart rate; SV= stroke volume; pO2= arterial O2 tension; pCO2= arterial CO2 tension.

Applicant's summary and conclusion

Conclusions:

Under the conditions of this test, aerosol of the test material was considered not to have adverse cardiopulmonary effects in dogs.

Executive summary:

A study was conducted on anesthetized dogs to evaluate the effect of test material submicron aerosol (upto 15.8 mg/m3 for 7.5 to 240 min) on cardiopulmonary mechanics.

Aerosols generated from 0.1 and 1% solutions of the test material were exposed to one test group for 7.5 min and aerosols from 0.5% solution were exposed to the other group for 4 h. Measurements of lung volume, total respiratory resistance, static lung compliance, and functional residual capacity, breathing mechanics and hemodynamics were performed following the exposure at different intervals.

Under the conditions of this test, aerosol of the test material was considered not to have adverse cardiopulmonary effects in dogs.