Filter Paper-collected Blood Lead Testing in Children

The Editorial “Filter Paper Lead Testing” by Moyer et al. (1) repeats previously raised hypothetical and unsubstantiated claims on filter paper (FP collection-based) blood lead testing (1)(2)(3)(4). All the theoretical charges were appropriately rebutted in the past based on published evidence (5)(6)(7)(8)(9). The peer-reviewed scientific literature supports the clinical usefulness of FP-collected blood samples in childhood lead poisoning screenings (10)(11)(12)(13)(14)(15)(16)(17)(18)(19).The Editorial’s authors (1) used references that do not support their statements: one of the references lacks entirely the topic of lead testing for which it was used. Worse yet, available references were omitted from the Editorial that support FP collection-based methods. The following comments and references attempt to correct these mistakes and provide accurate documentation from the scientific literature on FP.Reference 9 in the Editorial (14) is cited for support of “low extraction recoveries” of lead from FP. This study is based on a method that is a direct analysis that does not require an extraction (14). The same reference is cited to support the statements that contamination occurs as a result of “high and variable lead content of the FP or by contamination encountered in the sampling process”. The reference did not address FP blank lead concentration issues or that contamination caused any unusual problems during sample collection.The wrong volume and page numbers are cited for reference 8 in the Editorial (18). The work of Cernik (18) and O’Broin et al. (20) are used to support “nonreproducibility of blood spotting because of differences in hematocrit [Hct] and hemoglobin [Hb]” (1). Cernik (18) studied neither Hct nor Hb. His article investigated the effects of … [↵][1]aAuthor for correspondence. [1]: #xref-corresp-1-1