Exposição ambiental a interferentes endócrinos com atividade estrogênica e sua associação com distúrbios puberais em crianças Environmental exposure to endocrine disruptors with estrogenic activity and the association with pubertal disorders in children

A substância exógena que causa efeitos adversos na saúde de um organismo ou sua descendência, como resultado de distúrbios na função hormonal, é denominada interferente endócrino. Nos últimos anos, produtos ambientais com atividades hormonais têm sido documentados como causadores de anormalidades puberais ou reprodutivas em animais. Os poucos casos comprovados em humanos foram aqueles relacionados a exposições acidentais. Apesar disso, pediatras e pais recomendam a suspensão de todos os alimentos potencialmente contaminados, em especial carne (aves, gado) e derivados da soja quando a criança apresenta alguma alteração puberal. Estas recomendações, se não embasadas cientificamente, podem ter conseqüências deletérias, não apenas pela eliminação de fontes protéicas da dieta, como também por retardar a investigação de causas tratáveis. Por outro lado, a não investigação dos efeitos adversos destes produtos é da mesma forma danosa. Esta revisão descreve os principais interferentes endócrinos responsáveis por alterações puberais em humanos e conclui que, excetuando exposições acidentais a altas quantidades destes produtos, mais estudos são necessários para responsabilizar a ação crônica e em baixas doses destas substâncias na alteração do tempo de desenvolvimento puberal em nossa espécie.<br>Endocrine disruptors are exogenous substances with adverse health effects in intact organisms or their progeny, secondary to changes in endocrine function. Recent years have witnessed constant reports of environmental factors with hormone-like effects causing pubertal or reproductive abnormalities in animals. The few cases proven to be associated with pubertal disorders in humans have been related to accidental exposure. Nevertheless, pediatricians and parents recommend suspending all possible estrogen-contaminated food, especially meat (poultry, beef) and soy products, when the child presents with a pubertal disorder. These recommendations, if not scientifically sound, may have deleterious consequences by eliminating sources of dietary protein and possibly delaying the investigation of other potential and treatable causes. On the other hand, not investigating potential side effects of these products could have similar harmful effects. The current article describes the main endocrine disruptors associated with pubertal disorders in humans and concludes that except for accidental exposure to high doses, more research is needed on the effects of chronic and low-dose exposures in altering human pubertal development

Relationships between school climate, bullying and delinquent behaviours

© 2017 Springer Science+Business Media B.V. Given that schools are, potentially, powerful sites for influencing adolescent behaviour, it is important that there is greater understanding of the psychosocial aspects of the school climate that can be leveraged for this purpose. The research reported in this article used structural equation modelling (with data from a sample of 6120 students at Australian high schools) to examine the influence of the psychosocial school-level environment on students’ self-reported experiences of bully victimisation (i.e. being victims of bullying) and engagement in delinquent behaviours. Further, we examined whether bully victimisation mediated the relationships between school climate variables and delinquent behaviours. School connectedness and rule clarity were negatively associated with both bully victimisation and delinquency (p &lt; 0.05), and teacher support was negatively associated with bully victimisation (p &lt; 0.01), confirming the importance of these aspects of the school-level environment. However, affirming diversity and reporting and seeking help both had positive influences on bully victimisation (p &lt; 0.05), raising concerns about the ways in which these aspects of the school-level environment might have been promoted. Importantly, bully victimisation was found to mediate the influence of five of the six school climate constructs on delinquent behaviours (p &lt; 0.001). This study advance our understanding of how specific aspects of the school climate influence the prevalence of bullying and delinquent behaviour, adding weight to the call for educators to actively monitor and enhance psychosocial aspects of the school climate in order to improve student behavioural outcomes