J Korean Med Sci.  2017 Jul;32(7):1097-1104. 10.3346/jkms.2017.32.7.1097.

High Maternal Blood Mercury Level Is Associated with Low Verbal IQ in Children

• Jeong KS
• Park H
• Ha E
• Shin J
• Hong YC
• Ha M
• Park H
• Kim BN
• Lee B
• Lee SJ
• Lee KY
• Kim JH
• Kim Y

• KMID: 2379603
• DOI: http://doi.org/10.3346/jkms.2017.32.7.1097

Abstract

The objective of the present study was to investigate the relationship of IQ in children with maternal blood mercury concentration during late pregnancy. The present study is a component of the Mothers and Children's Environmental Health (MOCEH) study, a multi-center birth cohort project in Korea that began in 2006. The study cohort consisted of 553 children whose mothers underwent testing for blood mercury during late pregnancy. The children were given the Korean language version of the Wechsler Preschool and Primary Scale of Intelligence, revised edition (WPPSI-R) at 60 months of age. Multivariate linear regression analysis, with adjustment for covariates, was used to assess the relationship between verbal, performance, and total IQ in children and blood mercury concentration of mothers during late pregnancy. The results of multivariate linear regression analysis indicated that a doubling of blood mercury was associated with the decrease in verbal and total IQ by 2.482 (95% confidence interval [CI], 0.749-4.214) and 2.402 (95% CI, 0.526-4.279), respectively, after adjustment. This inverse association remained after further adjustment for blood lead concentration. Fish intake is an effect modifier of child IQ. In conclusion, high maternal blood mercury level is associated with low verbal IQ in children.

Keyword

Blood Mercury; Blood Lead; Fish; IQ; WPPSI-R

MeSH Terms

Child*
Cohort Studies
Environmental Health
Humans
Intelligence
Korea
Linear Models
Mothers
Parturition
Pregnancy

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