Diet restriction and exercise influence Pb+2 distribution

Wood cjwood at globalnet.co.uk
Sun Sep 19 19:40:22 EST 1999

"c. miller" wrote:

> Subject: Diet restriction and exercise influence Pb+2 distribution
> S. Han et al., report a nice study in the Aug. '99 issue of Environ. Health
> Perspect. (vol. 107, p. 657). Rats dosed with lead and then subjected to
> (20% or 40%) caloric restriction or exercise (swimming) to induce weight
> loss had greater levels of lead in systemic organs and blood. However, a
> significant drop of lead in the bone compartment was not observed. The
> authors speculate that only small amounts of bone Pb need be mobilized in
> order to account for the elevated tissue levels of Pb in the exercising and
> calorie-restricted animals. Alternatively, the existing Pb could have been
> selectively retained or mobilized from soft tissues or other stores (fat?).
> Interestingly, rats that lost weight by exercise had lower tissue levels of
> lead in comparison to calorie-restricted rats.
> Could this result mean that exercise-induced weight loss somehow mobilizes
> less toxicants in comparison to reduced food intake (in humans, too)? If
> so, what is the mechanism? More importantly, did the weight-loss induced Pb
> increases in tissues result in any significant or additional toxicity (or
> is weight-loss induced toxicity an urban myth)? I am still looking for
> actual references (in the peer-reviewed literature, please) for similar
> studies on lipophilic toxicants like DDT, other pesticides, PCBs, and TCDD.
> Best of results,
> Chuck

Dear Dr Miller,

Sorry for the delay in getting back to you.  Here are some of the references I
promised.  I hope you find them relevant and of interest:

Tretjak Z, Sheilds M and Beckmann SL (1990) - PCB Reduction and clinical
improvement by detoxification: An unexploited approach?  Human & Experimental
Toxicology 9:235-244

Schnare DW, Denk G, Sheilds M & Brunton S (1982) - Evaluation of a
detoxification regimen for fat stored xenobiotics.  Med Hyp 9:265-282

Schnare DW & Robinson PC (1986) - Reduction of human body burdens of
hexachlorobenzene and polychlorinated biphenyls.  In Hexachlorobenzene:
Proceedings of an International Symposium, CR Morris & JRP Cabral, eds,
International Agency for Research on Cancer, Lyon, France, pp 597-603

Roehm D (1983) Effects of a program of sauna baths and megavitamins on adipose
DDE and PCBs and on clearing symptoms of Agent Orange (dioxin) toxocity.  Clin
Res 31 (2):243a

Schnare DW, Ben M and Sheilds MG (1984) - Body burden reductions of PCBs, PBBs
and chlorinated pesticides in human subjects.  Ambio 13:278-380

More to follow very soon.  I've just GOT to go to bed now.


John Wood

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