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

AX5-26
Subject
Monkey,
cynomolgus,
9–10 yrs of age
Rat, male,
adult
Exposure
Protocol
50 or 100 µg/kg/d
Pb(Ac) 2
Table AX5-3.4 (cont’d). Summary of Key Studies on Neurobehavioral Toxicity
500 ppm Pb(Ac) 2 in chow for
105 days
Rat, LE 1500 ppm Pb(Ac) 2 gestation
and lactation
Rat, Wistar,
male
Rat, LE,
female
Rat, LE, male
and female
100 mg/kg/body weight by
injection
75 or 300 ppm Pb(Ac) 2 in
water GD0 experimental use
500 ppm Pb choride during
lactation
Rat, LE 250 ppm Pb(Ac) 2 chronically
from gestation
Peak Blood Pb
or [Pb] Used Observed Effects Reference
15.4 and
25.4 µg/dL; 10.9
and 13.1 µg/dL,
steady state
Pb-induced impairment in the presence, but not the absence, of irrelevant cues;
in the lower-dose group monkeys, impairment ended when the irrelevant
stimuli became familiar.
Gilbert and Rice
(1987)
28 µg/dL Chronic Pb exposure attenuates cocaine-induced behavioral activation. Grover et al.
(1993)
3.9 µg/dL at
PND 50
Pb + enriched environment: enhanced performance in water maze; increased
gene expression in the hipppocampus of NMDAR subunit 1 and BDNF.
Not reported Pb-induced deficits in memory component of the radial arm maze test and in
retention of passive avoidance learning.
Guilarte et al.
(2003)
Haider et al.
(2005)
51 µg/dL Impairment of reversal learning as an associative deficit. Hilson and Strupp
(1997)
42 µg/dL PND 11: no Pb-induced sex differences, effects on pup activity, and
differences in pup retrieval by dams.
PND 26: Pb treatment influenced all social behavior tested (i.e., investigation
duration and frequency, crossover frequency, pinning) but did not change
activity levels.
PND 36: Pb-treated pups demonstrated increased crossover frequencies but no
change in activity levels compared to controls.
Hippocampal
Pb levels
PND 21: 1.73;
PND 56: 1.02;
PND 91:
0.91 µg/g
Pb-exposure had no effect on working memory at any age tested, but did affect
reference memory (significant in females and nearly significant in males) in the
PND 21 rats.
Holloway and
Thor (1987)
Jett et al. (1997)