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Environ Health Prev Med (2012) 17:2733 DOI 10.1007/s12199-011-0216-z
REGULAR ARTICLE
Blood lead levels of contemporary Japanese children
Jun Yoshinaga Mai Takagi Kumiko Yamasaki
Sayaka Tamiya Chiho Watanabe
Masayuki Kaji
Received: 20 January 2011 / Accepted: 4 April 2011 / Published online: 23 April 2011 The Japanese Society for Hygiene 2011
AbstractObjectives Lead concentrations in whole blood (BPb) of Japanese children were measured to obtain insight into the sources of variation and to estimate health risk.
Methods Blood samples were taken from 352 children (aged 114 years) at pediatric clinics/hospitals in 3 regions of Japan (Tokyo, Shizuoka, and Osaka) during 20052006 (Shizuoka only) and 20082010 (3 regions), and BPb was measured by inductively coupled plasma mass spectrometry after acid digestion.
Results Geometric mean BPb of the 352 children was1.07 lg/dL, among the lowest in the world. Based on this result, the probability of exceeding BPb 10 lg/dL, the action level proposed by the US Centers for Disease Control and Prevention, in general Japanese children was estimated to be negligible. There was a signicant negative correlation between BPb and age, while sex difference was not signicant. BPb was signicantly lower in subjects in Tokyo than in the other two regions. Age-adjusted mean BPb was signicantly higher in children with a family member who smoked in their presence than in those who did not have such a family member, indicating that passive smoking had a signicant effect on BPb.
Conclusions Health risk of lead exposure is minimal in Japanese children. To lower the exposure level further, reduction of passive smoking is suggested as one of the effective measures.
Keywords Blood Lead Children Variation
Passive smoking
Introduction
Lead (Pb) is a well-known neurotoxicant. A number of epidemiologic studies done since the 1980s have revealed that Pb impairs normal development of cognitive functions of children [1]. Exposure to Pb has been related to lower intelligence quotient (IQ) [2], poor academic achievement [3], and delinquent behavior [4]. Moreover, concern has recently been raised that adverse effects are seen at exposure levels lower than were considered safe in the past [5, 6]. Schwartz [7] and Lanphear et al. [8] suggested that there is no threshold for Pb exposure below which no adverse effect on cognitive development was observed.
Lead concentration in whole...