Dried Blood Spot (DBS) Sampling for Biomonitoring in Occupational Settings

Postdoctoral Research Trainee: Lei Huang, PhD, University of Michigan

Faculty Sponsor: Stuart Batterman, PhD, MS, Professor of Environmental Health Sciences and Civil & Environmental Engineering at the University of Michigan

The use of dried blood spots (DBS) as a sampling approach for biomonitoring among infants has increased dramatically in recent years due to its convenience, safety, low cost and flexibility. While the amount of blood deposited as a DBS is only about 50 – 80 μl, in recent years investigators have been able to detect numerous biological and chemical agents from DBSs, and often, from a subset of the DBS (e.g., 3.2 mm dia punch). Despite nearly universal use among newborns, DBS have rarely been applied in occupational settings. Thus, one objective of the proposed study is to investigate the application of DBS sampling for occupational exposure assessment. This work will focus on exposure to brominated flame retardant (BFR) chemicals, e.g., polybrominated diphenyl ethers (PBDEs), for workers in the waste and recycling industries that handle electronic waste (e-waste) and foam waste that is known to contain BFRs. The second objective is to obtain preliminary data on BFR exposures of waste and recycling workers. The pilot project has four specific aims: (1) measurement of BFR levels in blood of workers from electronics/foam recycling facilities; (2) comparison of measurements using DBS and conventional venous blood samples; (3) comparison of BFR levels among waste/recycling workers to those of the general public; and (4) investigation of barriers and opportunities of using DBSs in occupational settings.

In this pilot study, we will recruit 25 workers at waste and recycling facilities. For each worker, we will collect DBS samples as well as traditional venous blood samples. Each worker will also complete a questionnaire on demographics, present and previous work activities, leisure activities, residential PBDE exposures, as well as dietary and smoking habits. The blood and DBS samples will be analyzed for BFR concentrations using methods that are well-established in our laboratory. Analyses will include a comparison of BFR concentrations and compositions between occupationally exposed workers and a nationally-representative non-occupationally exposed group, taken from NHANEs and age- and gender-matched. We will compare BFR measurements using DBS and venous blood samples.

The proposed study will represent the first application of DBS to assess occupational exposure to BFRs, which include a number of contaminants of considerable interest. The study will demonstrate that DBS sampling is acceptable, accurate and appropriate in occupational settings. Analyses of sampling results will determine whether the workers have elevated exposures. This preliminary data may set the stage for future studies examining occupational exposures in the waste and recycling areas, as well as other studies examining the use of DBS samples for occupational exposure assessment. The proposed work is anticipated to result in a manuscript submitted to a peer review journal, a conference presentation, and occupational research training of a post-doctoral research fellow.