- Full (HTML) - Related EHP Articles - PubMed:Related Articles - PubMed:Citation - Cited in PMC - Purchase This Issue

Catherine D. Axtell,¹ Gary J. Myers,² Philip W. Davidson,³ Anna L. Choi,¹ Elsa Cernichiari,⁴ Jeanne Sloane-Reeves,³ Conrad Shamlaye,⁵ Christopher Cox,¹ and Thomas W. Clarkson⁴

¹Department of Biostatistics, ²Department of Neurology, ³Department of Pediatrics, and ⁴Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642 USA
⁵Ministry of Health, Republic of the Seychelles

Abstract

Controversy exists concerning the fetal risk associated with exposure to low-dose methylmercury from maternal fish consumption. Previous studies of the effects of acute prenatal mercury exposure identified delays in achieving developmental milestones among exposed children. This led to public health concern that prenatal low-dose exposure from fish consumption could adversely affect the fetus. We evaluated the effects of prenatal methylmercury exposure (through maternal fish consumption) on the age that children walked and first said words in the main study cohort of the Seychelles Child Development Study. We used semiparametric generalized additive models to identify nonlinearities in the relationships between prenatal exposure and developmental outcomes, after adjusting for covariates, and to evaluate their importance. Very slight delays (<1 day) in walking were seen as mercury levels increased from 0 to 7 ppm, but this effect did not persist at the higher exposure levels represented by the cohort, making it difficult to conclude that a cause and effect relationship existed at the exposure levels seen in this cohort. There was no evidence for any association between prenatal exposure and age at talking. Key words: child development, developmental milestones, generalized additive models, methylmercury, semiparametric modeling. Environ Health Perspect 106:559-563 (1998) . [Online 10 August 1998]

http://ehpnet1.niehs.nih.gov/docs/1998/106p559-563axtell/ abstract.html

Address correspondence to C.D. Axtell, Center for Health Promotion and Disease Prevention, University of New Mexico Health Sciences Center, 2701 Frontier NE, Surge Building Room 251, Albuquerque, NM 87131 USA.

This research was supported by grants ES-05497, T32 ES07271, and ES01247 from the National Institutes of Health, by a grant from the Food and Drug Administration, U.S. Department of Health and Human Services, and grants from the Ministry of Health, Republic of Seychelles and the Government of Sweden. The research was conducted with the collaboration of the Seychelles Child Development Study group.

Received 5 December 1997 ; accepted 28 April 1998.