Mineralogical and geochemical characterization of Johnson's baby powder from 1985: Evidence of contamination

• Published in: Applied clay science 2024-03, Vol.250, p.107252, Article 107252
• Main Authors: Wudke, Hannah, Brown, Kenneth, Murchland, Madeline, Gillis, Morgan, Gokey, Kailee, Bank, Justin, Lytle, Marion, McLeod, Claire L., Krekeler, Mark P.S.
• Format: Article
• Language: English
• Subjects: ICP-MS; Johnson's baby powder; Metal contamination; SEM; Talc; TEM
• ISSN: 0169-1317
• DOI: 10.1016/j.clay.2023.107252

A single bottle of unopened Johnson's baby powder with a manufacturing date of 1985 was investigated for potential geochemical contaminants of concern. Study of 3 replicate samples via basic powder X-ray diffraction (XRD) indicates talc is the dominant phase present with chlorite ± serpentine and no other major impurities are observed. Scanning electron microscopy (SEM) documented the presence of Ni as a minor component in observed Fe-sulfides and Cr was detected in chromite and/or chromian magnetite. Transmission electron microscopy (TEM) documented the presence of Ni within individual platy and fibrous talc particles. Repeat analysis (n = 10) of pressed powders (n = 5) via handheld X-ray fluorescence (XRF) yielded SiO2 contents of 57.40 to 58.28 wt% and MgO contents of 29.90 to 30.79 wt%. Data also documents the presence of Cr, Ni, Cu, Zn. Cu and Zn are interpreted to occur in Fe-sulfides. Subsequent duplicate analysis (n = 2) of 3 talc samples via high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) detected 4 trace metals present of concern: V, Co, Cr, and Ni. Across all sample runs (n = 6), V averaged 10.6 ppm (±0.5 ppm at 2σ), Co averaged 55.0 ppm (±4.3 ppm at 2σ), Cr averaged 400.9 ppm (±11.4 ppm at 2σ), and Ni averaged 1395.9 ppm (±105 ppm at 2σ). While a precise geologic source for the studied talc cannot be unequivocally identified based on the data collected in this study (and the sample bottle alone), a comparison with global talc deposits indicates a product origin likely associated with (ultra)mafic-hosted talc deposits based on Ni (ppm) and Cr (ppm) contents, as opposed to carbonate metasedimentary-hosted deposits. From this work, it can therefore be concluded that Ni- and Cr-bearing particles made it into the baby powder production chain of this manufacturer in 1985. This study provides a foundation for future mineral and geochemical characterization of past, present, and future consumer talc-related products and may provide context for health-related studies. [Display omitted] •Talc product safety is highly controversial.•A 1985 bottle of Johnson's baby powder was analyzed to investigate metals.•Averages are V (10.6 ppm), Co (55.0 ppm), Cr (400.9 ppm), Ni (1395.9 ppm).•Ni occurs in talc particles and sulfides; Cr occurs in spinel phases.•The product likely is from an (ultra)mafic-hosted talc deposit.