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

AX5-167
Table AX5-10.4 (cont’d). Lead, Oxidative Stress, and Chelation Therapy
Concentration and
Compound Duration Species Blood Lead Effects Reference
550 ppm Pb acetate,
oral DMSA treatment.
Pb acetate Dose to
achieve blood Pb
levels of 35–
40 µg/dL.
Biweekly dose
adjustments, oral
followed by treatment
with chelator.
5 mg Pb kg−1, i.p Pb
acetate followed by
chelators for various
time points.
50 mg/kg Pb as Pb
nitrate, i.p, two
injections, 16h apart
50% Ethanol, 0.5 mL,
two injections, 16 h
apart
0.1% Pb acetate in
drinking water with
and without Sodium
Molybdate, i.p
(A) Pb for 35 +
21 days
(B) Pb 35 days and
Pb and DMSA
for 21 days
(C) Pb 35 days and
DMSA for
21 days
(D) Acedified Di H2O
for 35 days and
Di water for
21 days
1 yr, chelator for
two successive
19 day period
following Pb
exposure.
6–7 Wk old male
Sprague-Dawley
rats
Infant rhesus
monkeys
Analyses at Day 5 Suckling Wistar
rats
Pb-exposed:
50 µg/dL
Pb 35 days: Ranged
from 5–20 µg/dL +
DMSA from 0–
240 µg/kg/d
Pb-exposed:
35–40 µg/dL
DMSA reversed the hematological effects of Pb, decreased the blood,
brain , bone, kidney and liver concentration and produced marked Pb
diuresis, even when challenged with ongoing Pb exposure.
Specific emphasis on the beneficial effects of succimer treatment to
cessation of Pb exposure. These data demonstrated that succimer
efficiently reduces blood Pb levels which does not persist beyond the
completion of treatment. They also demonstrate the relative benefit of
eliminating Pb exposures , which serves to underscore the importance of
primary prevention of Pb exposure. Neither DMSA treatment nor the
cessation of Pb exposure were beneficial in reducing skeletal Pb levels.
— Meso—DMSA is the treatment of choice for acute Pb poisoning in infants
compared to EDTA and Rac-DMSA.
24 h Male Albino rats — S-Adenosyl methionine confers protection against alterations in several
parameters (ALAD, GSH, MDA) indicative of lipid peroxidation in blood,
liver and brain in Pb and acute Pb and ethanol exposed animals as well as
the organ concentration of Pb.
4 wks Male Albino rats Pb-exposed:
39 µg/dL
Pb + chelators:
4.6–13.1 µg/dL
Sodium molybdate significantly protected the uptake of Pb in blood, liver
and kidney. The treatment with molybdate also restored the Pb induced
inhibited activity of blood δ-aminolevulinic acid dehydratase and the
elevation of blood Zn protoporphyrin , hepatic lipid peroxidation and
serum ceruloplasmin.
Pappas et al. (1995)
Smith et al. (2000)
Kostial et al. (1999)
Flora and Seth
(1999)
Flora et al. (1993)