I found this post on Adult metal chelation. Cant vouch for its validity but looks interesting

1. Clinical response to therapeutic agents in poisoning from mercury
vapor. Sunderman FW., Ann Clin Lab Sci. 1978 Jul-Aug; 8(4):259-69.
PMID: 210702

"Exposure to mercury vapors for an hour per working day over a period
of 13 years produced in a thermometer manufacturer severe signs and
symptoms of mercury poisoning.

Analyses of the patient's sweat indicated that appreciable amounts
of mercury were excreted by this route.

Following the alleviation of the severe symptoms by BAL, the patient
was placed on a regimen of daily sweats and physio-therapy for a
protracted period of several months. On this latter regimen, the
mercury levels in the urine, blood serum and sweat were decreased to
within the normal ranges of values."

2. The excretion of trace metals in human sweat. Cohn JR and EA
Emmett, Annals of Clinical and Laboratory Science, Vol 8, Issue 4,
270-275

"The concentrations of zinc, copper, iron, nickel, cadmium, lead,
manganese, sodium and chloride in the sweat of six males and three
females were determined after collections utilizing a total body
washdown technique. From our results, sweat appears to be an
important excretory pathway for zinc and copper.

The mean concentrations of nickel and cadmium in sweat were higher
than those reported for urine; that of lead was similar to urine.
The loss of manganese in sweat is significant."

3. Fire Engineering, June 2003. Downtown Medical: A Detoxification
Program for WTC Responders by David E. Root, M. D., MPH

"World Trade Center (WTC) - The first rescue workers started the
program (sauna detox) on September 28, 2002. From the beginning, it
was apparent that the program was causing changes. "One of the men
was in the sauna, and he touched his towel to his skin and it turned
blue." said Dr. Dahlgren. "His sweat was really blue, a bright blue
color. We cut out a section of the towel and sent it to the
laboratory for analysis, and it came back with very high levels of
manganese and other metals, too."

The finding had considerable interest for Dr. Dahlgren. "Manganese
is present in structural steel—about three percent of the steel is
manganese," he said. "So when the Trade Towers came down, they
undoubtedly exposed people to manganese vapor and dust. Manganese
has some interesting characteristics—it causes a disease identical
to Parkinson's that usually ends up appearing anywhere from 5 to 10
years after the exposure."

Clients continue to relate a variety of manifestations to clinic
director Jim Woodworth. "Men have come in to tell me their bowel
movements have been green or blue, or smelled like smoke. Some have
had black paste coming out of the pores of their skin in the sauna.
Their sweat has stained towels purple, blue, orange, yellow and
black." he said.

"One client complained that he could taste soot from the site in his
sweat in his mouth." said Woodworth. "We collected about two
tablespoons of his sweat and held it up to the light. There were
millions of tiny bits of dust—you could see it with the naked eye;
his sweat was grey."

4. A comparative study of copper, lead, cadmium and zinc in human
sweat and blood. Stauber JL, Florence TM. CSIRO Division of Energy
Chemistry, NSW, Australia. Sci Total Environ. 1988 Aug 1;74:235-47
PMID: 3222694

"Zinc, cadmium, lead and copper in sweat from 24 male and 39 female
volunteers were determined by anodic stripping voltammetry. Sweating
was induced on the forearms by pilocarpine iontophoresis.

Average values found for zinc, cadmium, lead and copper in sweat
from males were 181 (range 25-863), 1.4 (less than 0.5-10), 41 (6-
87) and 103 (less than 5-673) micrograms l-1, respectively. Zinc in
sweat from females was significantly higher than in sweat from males
(331 micrograms l-1, range 87-836 micrograms l-1), while sweat
copper and sweat lead in females were lower (29 micrograms Cu l-1,
range less than 5-146 micrograms Cu l-1 and 24 micrograms Pb l-1,
range less than 5-66 micrograms Pb l-1)."

5, Trace elements in the sweat of acclimatized persons. Omokhodion
FO, Howard JM. Department of Preventive and Social Medicine,
University College Hospital, Ibadan, Nigeria.

Clin Chim Acta. 1994 Nov; 231(1):23-8. PMID: 7704945

"Sweat samples were collected from the arms of 15 normal, healthy
subjects while they exercised on a cycle ergometer at room
temperature. Samples were analysed for copper, zinc, manganese,
nickel, cadmium and aluminium by atomic absorption
spectrophotometry. Mean sweat levels determined for each element
were as follows:

358.1 micrograms/l for Zn; 486.8 micrograms/l for Cu; 3.10
micrograms/l for Mn; 1.91 micrograms/l for Cd; 69.9 micrograms/l for
Ni; 15.0 micrograms/l for Al

It appears that substantial quantities of trace elements are
excreted in the sweat of those sweating habitually."

6. Detection of mercury and other undetermined materials in skin
biopsies of endemic pemphigus foliaceus.
Abreu Velez AM, Warfvinge G, Herrera WL, Abreu Velez CE, Montoya M
F, Hardy DM, Bollag WB, Hashimoto K., Am J Dermatopathol. 2003 Oct;
25(5):384-91. Institute of Molecular Medicine and Genetic Medical
College of Georgia, Augusta, GA 30912.

"A novel variant of endemic pemphigus foliaceus (EPF) was described
among individuals in an area surrounding El Bagre, Colombia, South
America. The population in this rural mining community is exposed to
high environmental levels of mercury, used for gold extraction, as
well as other minerals, metalloids, and trace elements (e. g.,
quartz, rutile, granite, magnetite, and almenite) and ultraviolet
radiation.

Microscopic analysis revealed mercuric sulfides/selenides
concentrated within and around the sweat gland epithelium, as well
as in dendritic cells."

8. Industrial exposure to mercury. In J.O. Nriagu, Ed.,
Biogeochemistry of Mercury, Amsterdam, Dr. Woodhall Stopford, Duke
University Medical Center Elsevier/North Holland), pp. 367-397, 1979.

a. "With prolonged or repeated severe exposures (to mercury), such
that removing the patient from further exposure does not result in
improvement in the clinical picture, further intervention to enhance
excretion is called for. By far the earliest known form of therapy,
and possibly still the most effective, is the induction of sweating
by the use of sauna or steam baths."

b. "Lovejoy et al. 1973 suggested that sweating might be a
reasonable form of therapy when they noted that sweat levels of
mercury were higher than those found in urine of workers in the cell
rooms of a chloralkali plant. As noted, sauna therapy of an
individual with evidence of chronic mercurialism was effective at
inducing a remarkable excretion of mercury via the sweat."

9. From "Mercury Study Report to Congress, Volume V: Health Effects
of Mercury and Mercury Compounds", 1997, U.S. Environmental
Protection Agency.

"Excretion of mercury after exposure of elemental mercury vapor may
occur via exhaled air, urine, feces, sweat, and saliva. Excretion
via sweat and saliva are thought to contribute only minimally to
total excretion under normal circumstances. In workers who have
perspired profusely, however, the total amount of mercury excreted
in the sweat during 90 minutes ranged from 50% to 90% of that found
in a 16-hour composite sample of urine (Lovejoy et al. 1974).