Reaction products of sodium glucoheptonate with zinc sulfate and sodium hydroxide

Additional toxicological data

Administrative data

Endpoint:

additional toxicological information

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2005

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:

Comparing Inhaled Ultrafine versus Fine Zinc Oxide Particles in Healthy Adults - A Human Inhalation Study

Author:

Beckett, W. S., Chalupa, D. F., Pauly-Brown, A., Speers, D. M., Stewart, J. C., Frampton, M. W., Utell, M. J., Huang, L.-S., Cox, C., Zareba, W., Oberdörster, G.

Year:

2005

Bibliographic source:

Am J Respir Crit Care Med Vol 171. pp 1129-1135, 2005

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Exposure–response relationships for respiratory, hematologic, and cardiovascular endpoints between ultrafine and accumulation mode zinc oxide particles were compared in a human inhalation study. 12 healthy adults inhaled 500 g/m3 of ultrafine zinc oxide, the same mass of fine zinc oxide, and filtered air while at rest for 2 hours. Pre-exposure and follow-up studies of symptoms, leukocyte surface markers, hemostasis, and cardiac electrophysiology were conducted to 24 hours post-exposure. Induced sputum was sampled 24 hours after exposure.

Test material

Test material information

Constituent 1

Reference substance name:

Zinc oxide

EC Number:

215-222-5

EC Name:

Zinc oxide

Cas Number:

1314-13-2

Molecular formula:

OZn

IUPAC Name:

oxozinc

Details on test material:

particle size: < 0.1 µm diameter and 0.1 - 1 µm diameter

Applicant's summary and conclusion

Conclusions:

The U.S. Occupational Safety and Health Administration (as matters stand 2005) permissible exposure limit for zinc oxide is 5.0 mg/m3 inspired air, fume or respirable dust, as an 8-hour time-weighed average, over a 40-hour working week.
No differences were detected between any of the three exposure conditions at this level of exposure. Freshly generated zinc oxide in the fine or ultrafine fractions inhaled by healthy subjects at rest at a concentration of 500 g/m3 for 2 hours is below the threshold for acute systemic effects as detected by these endpoints. The tested dose was too low a dose to show any effect, or a “no observable effect level” of exposure.

Executive summary:

Zinc oxide is a common, biologically active constituent of particulate air pollution as well as a workplace toxin. Exposure–response relationships for respiratory, hematologic, and cardiovascular endpoints between ultrafine and accumulation mode zinc oxide particles were compared. In a human inhalation study, 12 healthy adults inhaled 500 g/m3 of ultrafine zinc oxide, the same mass of fine zinc oxide, and filtered air while at rest for 2 hours. Pre-exposure and follow-up studies of symptoms, leukocyte surface markers, hemostasis, and cardiac electrophysiology were conducted to 24 hours post-exposure. Induced sputum was sampled 24 hours after exposure. No differences were detected between any of the three exposure conditions at this level of exposure. Freshly generated zinc oxide in the fine or ultrafine fractions inhaled by healthy subjects at rest at a concentration of 500 g/m3 for 2 hours is below the threshold for acute systemic effects as detected by these endpoints. The U.S. Occupational Safety and Health Administration (as matters stand 2005) permissible exposure limit for zinc oxide is 5.0 mg/m3 inspired air, fume or respirable dust, as an 8-hour time-weighed average, over a 40-hour working week. The tested dose was too low a dose to show any effect, or a “no observable effect level” of exposure.