Davidson Philip W, Myers Gary J, Cox Christopher, Wilding Gregory E, Shamlaye Conrad F, Huang Li Shan, Cernichiari Elsa, Sloane-Reeves Jean, Palumbo Donna, Clarkson Thomas W
The Department of Pediatrics, University of Rochester School of Medicine and Dentistry, Rochester, New York, 14642, USA.
Neurotoxicol Teratol. 2006 Sep-Oct;28(5):529-35. doi: 10.1016/j.ntt.2006.06.002. Epub 2006 Jun 29.
The Seychelles Child Development Study (SCDS) has been longitudinally following a cohort of over 700 children enrolled in 1989. Their mothers consumed a diet high in fish during pregnancy. Repeated examination of the SCDS cohort at six different ages through age 11 years has shown no pattern of adverse effects. Some early appearing beneficial associations between both prenatal and postnatal hair MeHg and several child development endpoints were noted. We hypothesized these might be related to micronutrients in the fish, but they were not found when the children reached middle school age. These findings suggest that the associations observed between MeHg and developmental outcomes may vary with developmental stage.
We examined the main cohort of the SCDS to determine if this might be true using a longitudinal multiple regression analysis design that focused on those endpoints that were repeatedly measured at different ages. The primary endpoint analyzed was global cognition, involving a measure of developmental quotient or IQ. Secondary analyses included other domains such as Reading and Mathematics scholastic achievement, social behavior, and memory. Analyses involved two different approaches, one including incorporation of a passage of time variable, the other including a difference of scores across time points.
No significant associations were found between prenatal MeHg exposure and any of the repeatedly measured endpoints.
These results suggest that even when individual subject variance is controlled there was no consistent pattern of associations between child development outcomes and prenatal exposures to MeHg from maternal consumption of a diet high in fish. The Seychellois diet contains about 10 times more ocean fish than is typically consumed by US citizens. Our primary focus on IQ should further inform growing scientific interest in the analysis of the risks and benefits of fish consumption on overall cognitive ability.
塞舌尔儿童发展研究（SCDS）对1989年招募的700多名儿童进行了纵向跟踪研究。这些儿童的母亲在孕期食用了富含鱼类的饮食。对SCDS队列在11岁之前的六个不同年龄阶段进行的反复检查显示，没有出现不良影响的模式。注意到产前和产后头发中的甲基汞（MeHg）与几个儿童发育终点之间存在一些早期出现的有益关联。我们推测这些可能与鱼类中的微量营养素有关，但当这些儿童进入中学年龄时，并未发现这种关联。这些发现表明，观察到的MeHg与发育结果之间的关联可能随发育阶段而变化。
我们对SCDS的主要队列进行了研究，采用纵向多元回归分析设计，以确定情况是否如此，该设计侧重于在不同年龄反复测量的那些终点。分析的主要终点是整体认知，涉及发育商数或智商的测量。二次分析包括其他领域，如阅读和数学学业成绩、社会行为和记忆力。分析涉及两种不同的方法，一种包括纳入时间变量，另一种包括各时间点得分的差异。
未发现产前MeHg暴露与任何反复测量的终点之间存在显著关联。
这些结果表明，即使控制了个体受试者的差异，儿童发育结果与母亲食用富含鱼类的饮食导致的产前MeHg暴露之间也没有一致的关联模式。塞舌尔人的饮食中海洋鱼类的摄入量约为美国公民通常摄入量的10倍。我们对智商的主要关注应进一步激发科学界对分析鱼类消费对整体认知能力的风险和益处的兴趣。
