title: Long term exposure to organochlorine pesticides and thyroid function in children from Cidade dos Meninos, Rio de Janeiro, Brazil.
abstract: A pesticide factory in Cidade dos Meninos village, Duque de Caxias County, Rio de Janeiro, Brazil, ended its activity in 1961, leading to widespread contamination of the environment by several organochlorine pesticides. The aim of this study was to investigate the effects of chronic exposure to organochlorine pesticides on thyroid hormone levels in children residing in Cidade dos Meninos. In a population-based survey carried out between 2003 and 2004, serum concentration of 19 pesticides and levels of free thyroxine (T4), total triiodothyronine (T3) and thyroid-stimulating hormone (TSH) were determined in 193 children younger than 15 years old. Multivariate linear regression was conducted to examine thyroid hormone levels according to quintiles of organochlorine exposure, controlling for age, gender and serum lipid content. Free T4 and TSH levels were within reference values (0.7-1.8 ng/dl and 0.35-5.5 mU/l), whereas total T3 was above the reference range (80-180 ng/dl) in 28% of children. More than 60% of the children had detectable levels of most organochlorine pesticides. With the exception of heptachlor and methoxychlor, total T3 levels showed a significant increasing linear trend regardless of pesticide type to which children were exposed. Free T4 levels were positively and significantly associated only with exposure to p,p'-DDD, endosulfan 1, and dieldrin. No significant trend was found for TSH. Data showed that exposure of children to organochlorine pesticides produced a significant increase in serum total T3 concentrations. The clinical implications of such a total T3 elevation and subsequent development are uncertain and warrant the need for health monitoring of these children.
authors: National School of Public Health, Oswaldo Cruz Foundation (Fiocruz), Rio de Janeiro, Brazil. cfreire@ugr.es
authors: Carmen
authors: C
authors: Freire
authors: Rosalina Jorge
authors: RJ
authors: Koifman
authors: Paula
authors: P
authors: Sarcinelli
authors: Ana Cristina
authors: AC
authors: Rosa
authors: Ruth
authors: R
authors: Clapauch
authors: Sergio
authors: S
authors: Koifman
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D002849:Chromatography, Gas; D004781:Environmental Exposure; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000097:blood / Q000633:toxicity*; D007223:Infant; D016014:Linear Models; D008055:Lipids / Q000097:blood; D010575:Pesticides / Q000097:blood / Q000633:toxicity*; D012737:Sex Factors; D052616:Solid Phase Extraction; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000187:drug effects*; D013963:Thyroid Hormones / Q000097:blood*; D014505:Urban Population
chemical_list: D006843:Hydrocarbons, Chlorinated; D008055:Lipids; D010575:Pesticides; D013963:Thyroid Hormones