Association between prenatal exposure to methylmercury and visuospatial ability at 10.7 years in the seychelles child development study

• Published in: Neurotoxicology (Park Forest South) Vol. 29; no. 3; pp. 453 - 459
• Main Authors: Davidson, Philip W., Jean-Sloane-Reeves, Myers, Gary J., Hansen, Ole Nørby, Huang, Li-Shan, Georger, Leslie A., Cox, Christopher, Thurston, Sally W., Shamlaye, Conrad F., Clarkson, Thomas W.
• Format: Journal Article
• Language: English
• Published: Orlando, FL Elsevier B.V 01-05-2008; Elsevier
• Subjects: Adult; Biological and medical sciences; Chemical and industrial products toxicology. Toxic occupational diseases; Child; Child Development - drug effects; Dose-Response Relationship, Drug; Female; Humans; Male; Medical sciences; Metals and various inorganic compounds; Methylmercury; Methylmercury Compounds - toxicity; Neuropsychological Tests; Pregnancy; Prenatal exposure; Prenatal Exposure Delayed Effects; Psychomotor Performance - drug effects; Regression Analysis; Reproducibility of Results; Seychelles; Space Perception - drug effects; Toxicology; Visual motor development; Visual Perception - drug effects; Indian Ocean Islands; Seychelles; Visual motor development; Prenatal exposure; Methylmercury; Human; Prenatal; Association; Vision; Development; Exposure; Mercury Organic compounds; Child; Heavy metal
• DOI: 10.1016/j.neuro.2008.02.009
• EISSN: 1872-9711
• ISSN: 0161-813X

The Seychelles Child Development Study was designed to test the hypothesis that prenatal exposure to MeHg from maternal consumption of a diet high in fish is detrimental to child neurodevelopment. To date, no consistent pattern of adverse associations between prenatal exposure and children's development has appeared. In a comprehensive review of developmental studies involving MeHg, a panel of experts recommended a more consistent use of the same endpoints across studies to facilitate comparisons. Both the SCDS and the Faeroe Islands studies administered the Bender Visual Motor Gestalt Test. However, the method of test administration and scoring used was different. We repeated the test on the SCDS Main Study children (mean age 10.7 years) using the same testing and scoring procedure reported by the Faeroe studies to obtain Copying Task and Reproduction Task scores. We found no association between prenatal MeHg exposure and Copying Task scores which was reported from the Faeroese study. However, our analysis did show a significant adverse association between MeHg and Reproduction Task scores with all the data (
p
=
0.04), but not when the single outlier was removed (
p
=
0.07). In a population whose exposure to MeHg is from fish consumption, we continue to find no consistent adverse association between MeHg and visual motor coordination.