title: Potential external contamination with bisphenol A and other ubiquitous organic environmental chemicals during biomonitoring analysis: an elusive laboratory challenge.
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.
  
  
  OBJECTIVE
  We examined the contamination with the target analytes during analysis of biological specimens in biomonitoring laboratories equipped with state-of-the-art analytical instrumentation.
  
  
  CONCLUSIONS
  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.
authors: Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
authors: Xiaoyun
authors: X
authors: Ye
authors: Xiaoliu
authors: X
authors: Zhou
authors: Ryan
authors: R
authors: Hennings
authors: Joshua
authors: J
authors: Kramer
authors: Antonia M
authors: AM
authors: Calafat
mesh_terms: D001559:Benzhydryl Compounds / Q000032:analysis* / Q000633:toxicity; D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis* / Q000633:toxicity; D010636:Phenols / Q000032:analysis* / Q000633:toxicity; D053719:Tandem Mass Spectrometry; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D004785:Environmental Pollutants; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds