Potential External Contamination with Bisphenol A and Other Ubiquitous Organic Environmental Chemicals during Biomonitoring Analysis: An Elusive Laboratory Challenge

Xiaoyun Ye, Xiaoliu Zhou, Ryan Hennings, Joshua Kramer, and Antonia M. Calafat

Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA

Abstract

Background: Biomonitoring studies are conducted to assess internal dose (i.e., body burden) to environmental chemicals. However, because of the ubiquitous presence in the environment of some of these chemicals, such as bisphenol A (BPA), external contamination during handling and analysis of the biospecimens collected for biomonitoring evaluations could compromise the reported concentrations of such chemicals.

Objectives: We examined the contamination with the target analytes during analysis of biological specimens in biomonitoring laboratories equipped with state-of-the-art analytical instrumentation.

Discussions: We present several case studies using the quantitative determination of BPA and other organic chemicals (i.e., benzophenone-3, triclosan, parabens) in human urine, milk, and serum to identify potential contamination sources when the biomarkers measured are ubiquitous environmental contaminants.

Conclusions: Contamination with target analytes during biomonitoring analysis could result from solvents and reagents, the experimental apparatus used, the laboratory environment, and/or even the analyst. For biomonotoring data to be valid—even when obtained from high-quality analytical methods and good laboratory practices—the following practices must be followed to identify and track unintended contamination with the target analytes during analysis of the biological specimens: strict quality control measures including use of laboratory blanks; replicate analyses; engineering controls (e.g., clean rooms, biosafety cabinets) as needed; and homogeneous matrix-based quality control materials within the expected concentration ranges of the study samples.

Key words: benzophenone-3, biomonitoring, bisphenol A, exposure assessment, parabens, reagent blank, triclosan.

Environ Health Perspect 121:283–286 (2013). http://dx.doi.org/10.1289/ehp.1206093 [Online 16 January 2013]

Address correspondence to A. Calafat, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F17, Atlanta, GA 30341 USA. Telephone: (770) 488-7891. E-mail: aic7@cdc.gov

This work was supported in part by appointments (R.H. and J.K.) to the Research Participation Program at the Centers for Disease Control and Prevention (CDC), administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and the CDC.

The authors complied with all needed research requirements regarding human subjects. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the CDC.

The authors declare they have no actual or potential competing financial interests.

Received 3 October 2012; Accepted 15 January 2013; Online 16 January 2013.