Air Quality Criteria for Lead Volume II of II - (NEPIS)(EPA) - US ...

AX5-169
Table AX5-10.4 (cont’d). Lead, Oxidative Stress, and Chelation Therapy
Concentration and
Compound Duration Species Blood Lead Effects Reference
0–500 µM Pb acetate 6 h CHO cells and —
2000 ppm of Pb
acetate in drinking
water for 5 wks
Taurine
1.1 kg/d
1 mg Pb2+/kg B.wt ,
i.p. Pb acetate
Pb as acetate, 400 mg
Pb2+/mL, drinking
water
0.5 mg/mL
L-methionine
100 µM/kg b.wt. Pb
acetate,
intramuscular, single
100 µg/ Pb acetate,
intra gastric, oral and
intraperitoneal,
treated with or with
out thiamin (25,
50 mg/kg b.wt) and or
Ca EDTA (50 mg/kg
B.wt
5 wks
6th wk
4 wks, treatment
with various
antioxidant in the
5th wk
Fischer 344 rats Controls: 0.43 µg/dL
Pb-exposed:
36.4 µg/dL
Pb + Taurine:
33.8 µg/dL
Antioxidant Taurine reversed the abnormalities associated with lipid
peroxidation parameters such as increased. Malondialdehyde formation
and decreased Glutathione and enhanced CHO cell survival. However,
was not effective in reducing cell and tissue Pb burden in CHO cells and
Pb exposed Fischer rats.
IVRI 2 CQ rats — Pb exposure resulted in increased lipid peroxidation, with tissue specific
changes in liver. Treatment of exposed rats with ascorbic acid and αtocopherol
lowered the lipid peroxidation.
10 days Kunming mice
—
4 wks post-Pb
exposure
—
L- methionine has an ameliorative effect on Pb toxicity–Methionine
reduced the decrease in Hb content and depressed body growth caused by
Pb. Treatment with dietary methione along with Pb decreased the MDA
formation as opposed to Pb, moderately reversed the decreased iron
content of the organs and decreased organ Pb content.
3 and 24 h Male Albino rats — Pb exposure resulted in significant increases in acid and alkaline
phosphatases, serum GOT and GPT, elevated liver and kidney lipid
peroxidation and decreased antioxidant enzymes at 3 and 24 h after
exposure. Selenium administration prior to Pb exposure produced
pronounced prophylactic effects against Pb exposure by enhancing
endogenous anti oxidant capacity.
3 days CD-1 mice — Two times more whole body Pb was retained by intraperitoneal injection
as compared to intragastric administration. Thiamin treatment increased
the whole body retention of both intragastric and intraperitoneal Pb by
about 10%. Calcium EDTA either alone or in combination with thiamin
reduced the whole body retention of Pb by about 14% regardless of the
route of exposure. Regardless of the route Ca EDTA in the combined
treatment reduced the relative retention of Pb in both in liver and kidney.
These studies indicate the combination treatment with thiamin and Ca
EDTA alters the distribution and retention of Pb in a manner which might
have therapeutic application.
Gurer et al. (2001)
Patra et al. (2001)
Xie et al. (2003)
Othman and El
Missiry (1998)
Kim et al. (1992)