Page 417 - Fundamentals of Air Pollution 3E

TABLE 22-2b
Summary of Lowest Observed Effect Levels for Key Lead-Induced Health Effects in Children

Lowest observed
effect level (PbB)" Heme synthesis and Neurological Renal system Gastrointestinal
(^tg/dl) hematological effects effects effects effects

80-100 Encephalopathic signs and Chronic nephropathy Colic, other overt
symptoms (aminoaciduria, etc.) gastrointestinal symptoms
70 Frank anemia I
60 Peripheral neuropathies I

50 ? *
40 Reduced hemoglobin Peripheral nerve dysfunction
synthesis (slowed NCVs)^
Elevated coproporphyrin CNS cognitive effects (1Q
deficits, etc.)
Increased urinary ALA C |
30 ? Vitamin D metabolism
1 interference
15 Erythrocyte protoporphyrin Altered CNS
elevation electrophysiological
response <
10 ALA-IT inhibition ?
1 i
Py-5-N activity inhibition^ ?
?

" PbB = blood lead concentrations.
* Py-5-N = pyrimidine-5'-nucleotidase.
' ALA, ALA-D - aminolevulinie acid dehydrase
d
NCV = nerve conduction velocity
Source: U.S. Environmental Protection Agency, Air Quality Criteria for Lead, EPA-600, EPA-600-8-83/028aF, June 1986,