Methylmercury Measurements in Dried Blood Spots from Electronic Waste Workers Sampled from Agbogbloshie, Ghana.

Biomonitoring methylmercury (MeHg) exposure is problematic in resource-limited settings and with difficult-to-access populations where traditional biomarker approaches present logistical, economic, and ethical issues. The present study aimed to validate the use of dried blood spots (DBS) to assess MeHg exposure in a real-world contaminated field setting. Whole-blood and DBS samples were collected from electronic waste workers (n = 20) from Agbogbloshie (Ghana) in 2017, and DBS were also artificially created in the laboratory using the field-collected blood. Whole-blood MeHg concentrations averaged 0.84 µg/L, which was not different from levels measured in the corresponding DBS samples (field-collected or artificially created). Whole-blood MeHg comprised 61% of the blood total Hg concentrations. Linear regression analysis revealed no differences in MeHg concentrations between whole-blood samples and field-collected DBS (slope 0.89, R2  = 0.94) and between field and laboratory DBS (slope 0.89, R2  = 0.96). The MeHg content in DBS punch blanks averaged 0.86 pg and thus was not of concern. These findings indicate that DBS are a suitable tool for assessing MeHg exposure in real-world environmental settings that may be heavily contaminated.  Environ Toxicol Chem 2021;40:2183-2188. © 2021 SETAC.