Study On The Relationship Between Lead Exposure And Intelligence Quotient, Nerve Behavior In Children

Objective:To assess whether elevations in blood lead level were associated with intelligence quotient and nerve behavior changes in children. Methods:Thirty-three children of lead expose and 33 normal children with the similarity in age,sex,parental education and home economic income were recruited by case-control design. Blood lead estimations were carried out using the potential stripping analysis. Subjects were considered to be lead-exposed if their lead level was higher than or equal to 100μg/L and nonexposed if their lead level was lower than 100μg/L. Two groups of child's guardian have filled in the self-made child family social environment and healthy examination table and the Achenbach baby behavior meter. Intelligent tests were carried out using Gesell Development Schedules by specialist. We analyzed the correlations among blood lead level, intelligent level and behavior change in two groups of children with the SPSS 11.5 version.Results:1. Blood lead level of the lead-exposed group is 104 ~ 243μg/L, and average blood lead level is (150.33±37.61)μg/L. Blood lead level of the nonexposed group is 3～97μg/L, and average blood lead level is (29.33±23.32)μg/L. Two groups of blood lead level has extremely significant difference by the student's t test(t=13.142,P<0.01). The blood lead level does not have difference in sex by the student's t test(t=0.058,P>0.05).2.The blood lead level and the child's adaptiveness behavior DQ, big movement DQ, fine movement DQ, language DQ and individual-public relations behavior DQ assume the obvious negative correlational dependence(r=-0.656,P<0.01;r=-0.438,P<0.01;r=-0.553,P<0.01;r=-0.614,P<0.01;r=-0.573,P<0.01). The score of the lead-exposed group separately falls behind 19.36, 12.12, 17.76, 20.88 and 14.19 than that of the nonexposed group in adaptiveness behavior DQ, big movement DQ, fine movement DQ, language DQ, individual-public relations behavior DQ. Two groups of DQ score has extremely significant difference by the student's t test(t=-7.393,P<0.01;t=-4.040,P<0.01;t =-4.728,P<0.01;t=-6.335,P <0.01;t=-5.101,P<0.01).3.The number of melancholy and attack in lead-exposed and nonexposed group has extremely significant difference(χ2=8.943,P<0.01;χ2=8.075,P<0.01). The number of public relations flinch, sleep question, body sues states and destruction in two groups does not have difference(χ2=2.583,P>0.05;χ2=3.667,P>0.05;χ2=0.407,P>0.05;χ2=0.982,P>0.05). Analyzing various behavior factor score of two groups, 6 aspects difference in public relations flinch, melancholy, body sues states, attack, destruction and total score has statistics significance(P<0.05), and difference in sleep question has non- statistics significance(P>0.05). Conclusion:The blood lead level and the child's adaptiveness behavior DQ, big movement DQ, fine movement DQ, language DQ and individual-public relations behavior DQ assume the obvious negative correlational dependence. The score of the lead-exposed group is lower than that of the nonexposed group in adaptiveness behavior DQ, big movement DQ, fine movement DQ, language DQ, individual-public relations behavior DQ. The behavior abnormal number of the lead-exposed group is more than that of the nonexposed group, and the behavior abnormalcy mainly displays in public relations flinch, melancholy, body sues states, attack and destruction. Therefore, the synthetic preventing and treating measures should be early taken to the lead-exposed children.