Subclinical effects of prenatal methylmercury exposure on cardiac autonomic function in Japanese children

Katsuyuki Murata, Mineshi Sakamoto, Kunihiko Nakai, Miwako Dakeishi, Toyoto Iwata, Xiao Jie Liu, Hiroshi Satoh

Research output: Contribution to journalArticlepeer-review

34 Citations (Scopus)

Abstract

Objectives: The subclinical effects of prenatal exposure to methylmercury from fish consumption on the cardiac autonomic function were assessed in 136 Japanese 7-year-old children recruited for this study. Methods: Samples of child's hair and dry umbilical cord preserved were collected, and hair mercury and cord tissue methylmercury concentrations were determined as current and prenatal exposure biomarkers, respectively. Cardiac autonomic indicators of parasympathetic and sympathetic activities were calculated from the electrocardiographic RR intervals measured. Results: In the children, the cord tissue methylmer cury (0.017-0.367, median 0.089 μg/g) was not significantly correlated with the hair mercury (0.43-6.32, median 1.66 μg/g). The cord tissue methylmercury was related negatively to parasympathetic components of cardiac autonomic indicators (P<0.05) and positively to sympathovagal indices (P<0.05), even after correction for possible confounders such as age and sex, although the hair mercury was not significantly correlated with any cardiac autonomic indicators. Conclusions: Despite the potential limitations involved in the retrospective study, these findings suggest that prenatal methylmercury exposure (median of estimated maternal hair mercury at parturition, 2.24 μg/g) may be associated with reduced parasympathetic activity and/or sympathovagal shift.

Original languageEnglish
Pages (from-to)379-386
Number of pages8
JournalInternational Archives of Occupational and Environmental Health
Volume79
Issue number5
DOIs
Publication statusPublished - 2006 May

Keywords

  • Cardiac autonomic function
  • Methylmercury
  • Prenatal exposure
  • Retrospective study

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health

Fingerprint

Dive into the research topics of 'Subclinical effects of prenatal methylmercury exposure on cardiac autonomic function in Japanese children'. Together they form a unique fingerprint.

Cite this