title: The effect of lead on brainstem auditory evoked potentials in children.
abstract: OBJECTIVE
  To determine whether lead affects brainstem auditory evoked potentials (BAEPs) in low-to-moderate lead exposed children.
  
  
  METHODS
  BAEPs were recorded from 114 asymptomatic children aged 1 - 6 years. Average values were calculated for peak latency (PL) and amplitude (Amp). Whole blood lead (PbB) levels were assessed by graphite furnace atomic absorption spectroscopy. Based on their PbB levels, subjects were divided into low lead (PbB < 100 micro g/L) and high lead subgroups (PbB > or = 100 micro g/L).
  
  
  RESULTS
  The PbB levels of the 114 subjects ranged from 32.0 to 380.0 micro g/L in a positively skewed distribution. The median of PbB levels was 90.0 micro g/L while the arithmetic average was 88.0 micro g/L. Of the subjects, 43.0% (49/114) had levels equal to or greater than 100 micro g/L. Bilateral PLs I, V, and III of the left ear in the high lead subgroup were significantly longer than those in the low lead subgroup (P < 0.05). A positive correlation was found between PbB levels and bilateral PLs I, V and III of the left ear (P < 0.05), after controlling for age and gender as confounding factors. A significant and positive correlation between PbB levels and PL I of the left ear, even when PbB levels were lower than 100 micro g/L, in the low subgroup (r = 0.295, P = 0.019) was also found.
  
  
  CONCLUSIONS
  Lead poisoning in children younger than 6 years old is a very serious problem to which close attention should be paid. The indications that lead prolongs partial PLs may imply that lead, even at PbB levels lower than 100 micro g/L, impairs both the peripheral and the central portions of the auditory system. BAEPs may be a sensitive detector of subclinical lead exposure effects on the nervous system in children.
authors.affiliation: Department of Medicine, Children's Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China. zou108cc@yahoo.com
authors.forename: Chaochun
authors.initials: C
authors.lastname: Zou
authors.forename: Zhengyan
authors.initials: Z
authors.lastname: Zhao
authors.forename: Lanfang
authors.initials: L
authors.lastname: Tang
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Chen
authors.forename: Lizhong
authors.initials: L
authors.lastname: Du
mesh_terms: D002648:Child; D002675:Child, Preschool; D016057:Evoked Potentials, Auditory, Brain Stem / Q000187:drug effects*; D005260:Female; D006801:Humans; D007223:Infant; D007854:Lead / Q000097:blood / Q000633:toxicity*; D007855:Lead Poisoning / Q000503:physiopathology; D008297:Male
chemical_list: D007854:Lead