SIGNS OF ENHANCED NEUROMOTOR MATURATION IN CHILDREN DUE TO PERINATAL LOAD WITH BACKGROUND LEVELS OF DIOXINS - FOLLOW-UP UNTIL AGE 2 YEARS AND 7 MONTHS

We investigated psychomotor development (Bayley-test) and neuromotor f unctioning (Hempel-test) in a group of children with known perinatal l oad with background levels of dioxins. Bayley-test (n=32) at 2 years, and additionally investigated growth, medical history, physical condit ion, TT4, TT4/TBG, TSH, AST and ALT at the age of 2.5 years did not re veal abnormalities, or differences between the high- and the low-expos ure group. Although the Hempel-test was normal in all children (n=31), we found in 22 out of 29 items less suboptimal scores in the high-exp osure group; in five items this difference reached significance (p<0.0 5). Total-score and subtotal-score (posture of legs and feet excluded) revealed lower ''suboptimality-scores'' with a wider range in the hig h-exposure group in comparison to the low-exposure group (total-score p=0.008 mean 6.7 SD 3.6 and mean 9.3 SD 1.8 respectively and subtotal- score p=0.06 mean 4.5 SD 2.9 and mean 6.1 SD 1.6 respectively (Mann-Wh itney or Wilcoxon Two-Sample Test)). Similar signs of enhanced maturat ion have been described in the tadpole due to low dosis of TCDD. Refle xes were higher (p=0.02), with a wider range of findings in the high-e xposure group. Our hypothesis is that these findings may be due to thy roxine agonistic action of dioxins, which is in accordance with the ea rlier described signs of relatively high thyroid function in the first 11 weeks of life in this high-exposure group. Copyright (C) 1996 Else vier Science Ltd