Excretion of Ni, Pb, Cu, As, and Hg in Sweat under Two Sweating Conditions (2022)
https://pubmed.ncbi.nlm.nih.gov/35410004
Arsenic, cadmium, lead, and mercury in sweat: a systematic review (2012)
https://pubmed.ncbi.nlm.nih.gov/22505948
Changes in serum metal concentrations following high-intensity interval training: A 16-week pilot study (2025)
https://pubmed.ncbi.nlm.nih.gov/41092565
Lead
Lead was examined in eleven studies [3, 22, 26–28, 33–38]. In 1973, Hohnadel et al. suggested that “sauna bathing might provide a therapeutic method to increase elimination of toxic trace metals” [38]. In two males, 36% and 50% of sweat lead was of molecular weight > 30,000, as measured by ultrafiltration, suggesting excretion of organic complexes rather than simple ions [22]. Lead excretion was lower in females taking birth control medications compared with females not taking medications, or males [28]. Haber et al. found that prolonged endurance workouts (rowing) ameliorated elevated blood lead levels in exposed workers but did not alter levels in control subjects and did not affect urine levels [26]. They suggested that the elimination route was not urine, but potentially sweat or/and bile. Omokhodion and Crockford carried out several studies of trace elements in sweat, including a study of lead ingestion by two human participants [34]. Sweat lead levels did not increase immediately with elevated blood lead, although the authors make reference to an older study with longer followup wherein lead in underarm pads doubled in the five days following ingestion. Omokhodion and Howard also reported higher lead in sweat of exposed workers compared with unexposed controls [35], and in another study that sweat and blood lead levels were the only two variables that correlated among blood, urine, sweat, and saliva [36]. The English abstract of a 1991 case report in Russian indicated that sauna increased excretion of toxic elements and resulted in clinical improvements [27]. Sweat lead levels up to 283 μg/L have been observed in nonoccupationally exposed subjects [38] and up to 17,700 μg/L in workers [37], where it is noted that lead in sweat may partially originate from material absorbed within the skin that was not removed by pretest cleaning protocols [35]. Indeed, although dermal application of lead via hair follicles, sweat ducts, and diffusion does not result in immediate increases in blood or urine lead concentrations, dermal absorption was demonstrated using the Pb-204 isotope [43], lead powder, and salt [37].
If you are concerned about exposure to toxic metals, the above links show that sweating can be a significant way to excrete them. Exercise and saunas both help speed removal. ABN
UPDATE: I checked into this further and found that, while sweating does remove toxic metals, the volume of sweat is low compared to urine and thus, generally, the kidneys and liver do more. That said, sweating can be an important supplement for toxic metal removal and may remove metals stored in tissues which are not easily removed through the water-soluble urine route. Infrared saunas appear to be very good at removing metals and fat-soluble toxins stored in adipose tissue. ABN
American Buddhist Net 