Prenatal and postnatal lead exposures and intellectual development among 12-year-old Japanese children.
Environ Res
; 189: 109844, 2020 10.
Article
em En
| MEDLINE
| ID: mdl-32678746
ABSTRACT
BACKGROUND:
Low-level lead exposure during childhood is associated with deficit in child IQ. However, the association between prenatal lead exposure and child IQ remains inconsistent. The objective of our study was to examine the association between prenatal/postnatal lead exposure and child IQ at the age of 12.METHODS:
We obtained data pertaining to cord-blood and child-blood lead levels and IQ for 286 children from a prospective birth cohort study (Tohoku Study of Child Development). IQ was assessed using the Wechsler Intelligence Scale for Children-Fourth Edition. Simultaneously, the Boston Naming Test (BNT) was used to assess the children's language ability.RESULTS:
The median lead level in the cord blood was 0.8 µg/dL (5th-95th percentiles, 0.4-1.4 µg/dL), and that in the blood of 12-year-old children was 0.7 µg/dL (0.4-1.1 µg/dL). IQ and BNT scores were significantly lower in boys than in girls; therefore, multiple regression analysis was conducted separately for boys and girls. Among boys, IQ was associated with child-blood lead (B = -16.362, p = 0.033) but not cord-blood lead (B = -6.844, p = 0.309). When boys were divided into four groups according to the child-blood lead levels, there was a significant decreasing trend for IQ. The score with cues of the BNT was associated with both cord-blood (B = -5.893, p = 0.025) and child-blood (B = -7.108, p = 0.022) lead concentrations in boys. Among girls, there was no significant association of the outcomes with cord-blood or child-blood lead level.CONCLUSIONS:
These findings suggest that postnatal lead exposure adversely affects the intellectual ability in boys. Furthermore, the language ability is sensitive to prenatal/postnatal lead exposure in boys.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Efeitos Tardios da Exposição Pré-Natal
/
Chumbo
Tipo de estudo:
Etiology_studies
/
Incidence_studies
/
Observational_studies
/
Risk_factors_studies
Limite:
Child
/
Female
/
Humans
/
Male
/
Pregnancy
País/Região como assunto:
Asia
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article