High lead exposure and auditory sensory-neural function in Andean children.
We investigated blood lead (B-Pb) and mercury (B-Hg) levels and auditory sensory-neural function in 62 Andean school children living in a Pb-contaminated area of Ecuador and 14 children in a neighboring gold mining area with no known Pb exposure. The median B-Pb level for 62 children in the Pb-exposed group was 52.6 micrograms/dl (range 9.9-110.0 micrograms/dl) compared with 6.4 micrograms/dl (range 3.9-12.0 micrograms/dl) for the children in the non-Pb exposed group; the differences were statistically significant (p < 0.001). Auditory thresholds for the Pb-exposed group were normal at the pure tone frequencies of 0.25-8 kHz over the entire range of B-Pb levels, Auditory brain stem response tests in seven children with high B-Pb levels showed normal absolute peak and interpeak latencies. The median B-Hg levels were 0.16 micrograms/dl (range 0.04-0.58 micrograms/dl) for children in the Pb-exposed group and 0.22 micrograms/dl (range 0.1-0.44 micrograms/dl) for children in the non-Pb exposed gold mining area, and showed no significant relationship to auditory function.
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Department of Neurology/Biological Laboratories, Harvard University, Cambridge, MA 02138 USA.
Vahter
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Laurell
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Buchanan
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Ortega
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Skerfving
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D000293:Adolescent; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D016022:Case-Control Studies; D002516:Ceramics; D002648:Child; D002675:Child, Preschool; D004484:Ecuador; D004781:Environmental Exposure / Q000009:adverse effects*; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000139:chemically induced* / Q000175:diagnosis; D006801:Humans; D007855:Lead Poisoning / Q000097:blood / Q000150:complications*; D008297:Male