Overview
Bastos and Rocha matured a Portuguese bentonite with two mineral-medicinal waters under four stirring and light conditions for 90 days and characterized mineralogy, rheology, microbiology and trace elements. The article body prints trace-element values only for the starting bentonite (lead 2.7 ppm, nickel 250 ppm), the same material the authors characterized in their companion paper; peloid values are in supplementary tables that were not filed.
Key numbers
- Bentonite BV3: lead “2.7 ppm”, copper “93.7 ppm”, nickel “250 ppm”; arsenic, cadmium, chromium, manganese, antimony and vanadium not detectable (Discussion, p. 701).
- Arsenic, cadmium, antimony, thallium and others were not detected in the bentonite or the resulting peloids (Results, p. 690, citing Table S3).
Methods (brief)
Solids were analyzed by XRF and supernatants by ICP-MS; detection limits were set at three times the blank standard deviation but are not printed. Replicate RSD was 10 percent or less.
Evidence Fitness
Recorded as context: the only printed metal numbers repeat the bentonite characterization in Bastos et al. 2023 (Environmental Geochemistry and Health), and they conflict with it for chromium (not detectable here, 2140 ppm there), zinc and molybdenum. Peloid trace elements are only in unfiled supplements. Therapeutic peloid mud is a proxy for cosmetic-clay, and that page is not linked. The manifest note placing 2.7 ppm lead in a peloid is incorrect; it is the raw bentonite.