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Abstract
Mall has alway” been xpo ed to lead. but the amounts have
substantially increased a a byproduct of industrialization, The
inunedisre ource of lead. both natural and industrial. are air. water,
and food (Browder etal., 19 3).
III 1968, Baritrop reponed that in most communiti the
atmo pher and th diet contain small amounts of lead \ hich are
eontiuuou Jy inhaled and inge ted. Lead is a cumulative poison, 0 thar
toxicity is a function of both the magnitude of the dose and the rate of
admini tration,
The nervous sy .tem is a unique target for toxic agents in everal
ways. Fir I, the adult neuron does not divide and. therefore. replacement
of los 1 cells is nor possible. Second, there is II barrier to passage of many
blood-borne substances unless they are monopolar or are acrivel
rrar ported. Third, .in e the normal fun lion of the nervous ysrem
requires the action of it comp ex imegrared network clamll.g t even a
. mall portion of Ihe nerVOUS stem ometime call Ie 1.IJI in marked
effects all function (Wando (1Iu/ Cotin, 1991).
Ther is no thre ’hold below which lead r mains without eft; ct.
This sugge 1 rhflt any expo ire to lead is harmful to the central nervous
uem, Thi bas a . pecial relevance to infant and children. However
exposure to lead is preventable and its neurotoxicological effect are
potentially treatable There is environmental overexposur of children to
lead. arional Attention lind publi h alth effort are required to
minimize the problem. There is in ”ufiicient data regarding the full.