Biomonitoring Equivalents for interpretation of silver biomonitoring data in a risk assessment context

Lesa L Aylward; Gerald Bachler; Natalie von Goetz; Devika Poddalgoda; Sean M Hays; Andy Nong

doi:10.1016/j.ijheh.2016.05.005

Biomonitoring Equivalents for interpretation of silver biomonitoring data in a risk assessment context

Int J Hyg Environ Health. 2016 Aug;219(6):521-6. doi: 10.1016/j.ijheh.2016.05.005. Epub 2016 May 19.

Authors

Lesa L Aylward¹, Gerald Bachler², Natalie von Goetz³, Devika Poddalgoda⁴, Sean M Hays⁵, Andy Nong⁴

Affiliations

¹ Summit Toxicology, LLP, Falls Church, VA 22044 USA, USA. Electronic address: laylward@summittoxicology.com.
² Swiss Federal Institute of Technology (ETH), 8093 Zurich, Switzerland; Shell Health, Shell International B.V., P.O. Box 162, 2501 AN, The Netherlands.
³ Swiss Federal Institute of Technology (ETH), 8093 Zurich, Switzerland.
⁴ Health Canada, Ottawa, ON, Canada.
⁵ Summit Toxicology, LLP, Lyons, CO 90540, USA, USA.

PMID: 27283208
DOI: 10.1016/j.ijheh.2016.05.005

Abstract

Silver is widely used as an antimicrobial agent in both ionic and nanoparticle forms, and general population exposure to silver can occur through the presence of trace levels in foods and dusts, through dermal contact with treated textiles, from use of wound care products, and other sources. Biomonitoring for silver in blood or urine in persons in the general population is being conducted by the Canadian Health Measures Survey (CHMS). Tolerable exposure guidance values for silver designed to prevent adverse effects of excess exposure are available from the United States Environmental Protection Agency (an oral reference dose, or RfD), from the United States Food and Drug Administration (a draft provisional tolerable intake, or TI) and from literature evaluations of recent data on responses to nanoparticle silver (a recommended tolerable daily intake, or TDI). A current physiologically-based pharmacokinetic model is used to estimate Biomonitoring Equivalents (BEs) for silver, which are steady-state biomarker concentrations consistent with the RfD, provisional TI, or recommended TDI (BERfD, BETI, or BETDI, respectively). The BE values based on silver in whole blood range from 0.2 to 0.9μg/L. BE values for silver in urine were not derived due to low confidence in the predicted steady-state urinary silver excretion rates. Comparison of general population biomonitoring data from Canada to the derived BE values indicate that general population exposure levels are generally below levels consistent with current risk assessment-derived exposure guidance values.

Keywords: Biomonitoring; Blood; Risk assessment; Silver.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Canada
Environmental Monitoring
Environmental Pollutants* / analysis
Environmental Pollutants* / pharmacokinetics
Environmental Pollutants* / toxicity
Humans
Metal Nanoparticles* / analysis
Metal Nanoparticles* / toxicity
Models, Biological*
Risk Assessment
Silver* / analysis
Silver* / pharmacokinetics
Silver* / toxicity

Substances

Environmental Pollutants
Silver