RESUMO
OBJECTIVE: To assess the neurodevelopmental effects of the Great East Japan Earthquake in resident children. STUDY DESIGN: The disaster on March 11, 2011, caused severe damage to the Sanriku coastal area, where we had been conducting a birth cohort study since 2003. It occurred in the middle of our 7-year-old examination. Approximately 500 mother-child pairs were compulsorily divided into 2 groups: 123 children finished the examination in the predisaster period, and 289 did in the postdisaster period. The remainder died or moved from that area. At the time of 7-year-old examination, we administered the Wechsler Intelligence Scale for Children-Third Edition and electrocardiography to assess autonomic function. According to the Child Behavior Checklist for ages 2-3 years and the Kaufman Assessment Battery for Children that had been administered at 30 months and 42 months of age, respectively, there were no significant differences in them between the 2 groups. RESULTS: Verbal IQ, including information, arithmetic, and vocabulary subscores of the Wechsler Intelligence Scale for Children-Third Edition, at 7 years of age was significantly lower in the postdisaster group than in the predisaster group. However, there were no significant differences in performance IQ, full-scale IQ, or autonomic nervous indicators between the 2 groups. CONCLUSIONS: Since many schools were utilized as primary refuges after the disaster, the deficits in verbal IQ of 7-year-old children may have been due to the interrupted schooling. Further follow-up and more specific posttraumatic stress disorder testing will be required to determine the cause and long-term implications.
Assuntos
Desastres , Terremotos , Inteligência , Criança , Pré-Escolar , Estudos de Coortes , Eletrocardiografia , Feminino , Humanos , Testes de Inteligência , Japão , MasculinoRESUMO
BACKGROUND: The long-term neurotoxicity risks caused by prenatal exposures to pesticides are unclear, but a previous pilot study of Ecuadorian school children suggested that blood pressure and visuospatial processing may be vulnerable. OBJECTIVES: In northern Ecuador, where floriculture is intensive and relies on female employment, we carried out an intensive cross-sectional study to assess children's neurobehavioral functions at 6-8 years of age. METHODS: We examined all 87 children attending two grades in the local public school with an expanded battery of neurobehavioral tests. Information on pesticide exposure during the index pregnancy was obtained from maternal interview. The children's current pesticide exposure was assessed from the urinary excretion of organophosphate metabolites and erythrocyte acetylcholine esterase activity. RESULTS: Of 84 eligible participants, 35 were exposed to pesticides during pregnancy via maternal occupational exposure, and 23 had indirect exposure from paternal work. Twenty-two children had detectable current exposure irrespective of their prenatal exposure status. Only children with pre-natal exposure from maternal greenhouse work showed consistent deficits after covariate adjustment, which included stunting and socioeconomic variables. Exposure-related deficits were the strongest for motor speed (Finger Tapping Task), motor coordination (Santa Ana Form Board), visuospatial performance (Stanford-Binet Copying Test), and visual memory (Stanford-Binet Copying Recall Test). These associations corresponded to a developmental delay of 1.5-2 years. Prenatal pesticide exposure was also significantly associated with an average increase of 3.6 mmHg in systolic blood pressure and a slight decrease in body mass index of 1.1 kg/m2. Inclusion of the pilot data strengthened these results. CONCLUSIONS: These findings support the notion that prenatal exposure to pesticides-at levels not producing adverse health outcomes in the mother-can cause lasting adverse effects on brain development in children. Pesticide exposure therefore may contribute to a "silent pandemic" of developmental neurotoxicity.
Assuntos
Doenças dos Trabalhadores Agrícolas/induzido quimicamente , Deficiências do Desenvolvimento/induzido quimicamente , Exposição Ocupacional , Organofosfatos/toxicidade , Praguicidas/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Desempenho Psicomotor/efeitos dos fármacos , Adulto , Atenção/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Criança , Estudos Transversais , Equador , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Organofosfatos/urina , Praguicidas/urina , GravidezRESUMO
OBJECTIVE: To determine whether heart function in childhood is affected by exposure to methylmercury (MeHg) from seafood. STUDY DESIGN: Prospective study of a Faroese birth cohort (N=1022). Examinations at ages 7 and 14 years included blood pressure, heart rate variability (HRV) and its frequency components of autonomic origin, and brainstem auditory evoked potentials (BAEPs). Mercury concentrations were determined in cord blood and in the child's hair. RESULTS: Both low-frequency (LF) and high-frequency (HF) activities decreased by about 25% from 7 to 14 years; they correlated well with the blood pressures. A doubling of prenatal MeHg exposure was associated with a decrease in LF and HF powers of about 6.7% (P=.04) and in the coefficient of variation of the electrocardiographic R-R interval of 2.7% (P=.04) at age 14 years. No discernible effect on blood pressure was apparent. Decreased LF variability was associated with increased latency of BAEP peak III, but adjustment for MeHg exposure substantially attenuated this correlation. CONCLUSIONS: Methylmercury exposure was associated with decreased sympathetic (LF) and parasympathetic (HF) modulation of the HRV. Parallel MeHg-related delays of BAEP latencies may be caused by underlying MeHg neurotoxicity to brainstem nuclei.
Assuntos
Contaminação de Alimentos , Coração/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Alimentos Marinhos/efeitos adversos , Adolescente , Adulto , Pressão Sanguínea/fisiologia , Criança , Estudos de Coortes , Dinamarca , Exposição Ambiental/efeitos adversos , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Feminino , Seguimentos , Coração/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Sistema Nervoso Parassimpático/efeitos dos fármacos , Sistema Nervoso Parassimpático/fisiopatologia , Gravidez , Fatores Sexuais , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologiaRESUMO
OBJECTIVE: To determine possible exposure-associated delays in auditory brainstem evoked potential latencies as an objective measure of neurobehavioral toxicity in 14-year-old children with developmental exposure to methylmercury (MeHg) from seafood. STUDY DESIGN: Prospective study of a birth cohort in the Faroe Islands, where 878 of eligible children (87%) were examined at age 14 years. Latencies of brainstem evoked potential peaks I, III, and V at 20 and 40 Hz constituted the outcome variables. Mercury concentrations were determined in cord blood and maternal hair, and in the child's hair at ages 7 and 14. RESULTS: Latencies of peaks III and V increased by about 0.012 ms when the cord blood mercury concentration doubled. As seen at age 7 years, this effect appeared mainly within the I-III interpeak interval. Despite lower postnatal exposures, the child's hair mercury level at age 14 years was associated with prolonged III-V interpeak latencies. All benchmark dose results were similar to those obtained for dose-response relationships at age 7 years. CONCLUSIONS: The persistence of prolonged I-III interpeak intervals indicates that some neurotoxic effects from intrauterine MeHg exposure are irreversible. A change in vulnerability to MeHg toxicity is suggested by the apparent sensitivity of the peak III-V component to recent MeHg exposure.