The six laboratories in the CHEAR National Exposure Assessment Laboratory Network (also called the Lab Network or Lab Hubs) provide comprehensive, state-of-the-art laboratory services for analysis of biological samples from children’s health studies. The Lab Hubs can measure environmental exposures, including biological, psychosocial, chemical, and physical factors, as well as health-related biomarkers, such as indicators of immune activation or inflammation.
CHEAR provides three categories of analyses, each of which may be useful in different research contexts.
- Targeted Analysis
Hypothesis-driven analyses of specific contaminants, markers of exposure, and other substances known or suspected to affect health outcomes. Examples include specific pesticides in biological fluids and biomarkers of tobacco smoke exposure. Targeted analyses are typically performed for panels of chemically related compounds.
- Untargeted Analysis
Hypothesis-free exploratory analyses using advanced technologies to discover new associations between environmental chemicals or metabolites and health. Both endogenous metabolites and exogenous xenobiotics can be identified and measured. Techniques may include nuclear magnetic resonance (NMR) and mass spectrometry (MS) based metabolomics.
- Biological Response
Measurements of individual response to environmental stressors using established markers. Examples include measures of immune activation or inflammation and measures of response to psychosocial stress. CHEAR will provide analyses of biological response indicators only as secondary analyses in connection with targeted or untargeted exposure assessments.
Quality Assurance/Quality Control
CHEAR Lab Hubs have a commitment to quality assurance. They participate in national and international proficiency testing programs for trace elements and organic compounds multiple times each year. They also include appropriate blanks, checks for contamination control, internal QC samples, and NIST Standard Reference Materials in their analyses.
In addition, the Lab Hubs analyze CHEAR-specific reference materials. This enables the results to be compared to a known standard and to results from other laboratories, including comparisons across the CHEAR Lab Network, to ensure consistent results. The CHEAR Data Center reviews the reference and QC data to ensure quality and provides summaries of methods and QC results to CHEAR users as needed.