Investigation of the relationship between attention deficit and hyperactivity disorder in children and bisphenol a (BPA) and phthalate exposure

The Attention deficit and hyperactivity disorder (ADHD) is a neurodevelopmental disorder that occurs due to hyperactivity, attention deficit and intense impulsivity in children. The symptoms of this disease appear as cognitive, academic, behavioral, emotional and social functionality being negatively affected and the incidence of it is 9-15% especially in school age. The exact pathogenesis of this disorder is not known, but genetic imbalance of catecholamine metabolism in the cerebral cortex and various environmental factors may be the cause for the emergence of ADHD. Bisphenol A and phthalates are xenoestrogens, an important chemical endocrine disruptor that people are frequently exposed to in daily life and these substances have been detected in the urine, serum and milk (female individuals) of individuals exposed to these agents. Among the sources of bisphenol A and phthalates are polyvinyl chloride plastics used in baby bottle production, compact discs, thermal fax paper, paints, plastic toys, medical supplies, plastic film linings of the inner surface of beverage box. The present thesis work aimed to determine the relationship between ADHD and plastic exposure by measuring Bisphenol A (BPA) and phthalate levels in the urine samples of pediatric patients diagnosed with ADHD and thus, it was determined what should be considered in the prevention of the disease prophylactically. In this context, according to the results of the study conducted within the scope of the thesis, this disorder is more common in boys among the case and control groups and this was found to be higher in the 6-12 age group (76.4%). However, while the rate of consumption of ready-made water, the frequency of use of plastic toys and plastic flooring was significantly higher in the case group, there was no significant difference between the two groups in terms of the frequency of use of plastic household items, packaged foods and microwave ovens. In terms of biochemical parameters, there was no difference in urine BPA, Mono-2-carboxy-methylhexyl phthalate (MEHHP), Monobenzyl phthalate (MBzP) and Monocyclohexyl phthalate (MCHP) levels in the case group. In the multivariate linear regression analyzes performed, no significant relationship was found between BPA values in the urine and the use of plastic products. However, while the MBzP level was found to be high in children in the case group who frequently used tomato paste in a plastic container, MCHP was found to be low in the control group. In addition, a positive correlation was found between the frequency of consumption of plastic coated yogurt and the level of Mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) in the study group. An inverse relationship was found between the MBP value and the consumption of plastic coated buttermilk. While the MCHP value was higher in those who frequently consumed plastic-wrapped food, there was no difference in BPA in those who consumed hot drinks in plastic cups and an inverse relationship was frequently found in the MCHP control group, one of the phthalate metabolites. In the light of these results, it is thought that although the production and import of BPA and phthalate is restricted in our country, it may be in the content of some plastic storage containers, children's products and toys. In this way, it is seen that especially infants are exposed to phthalates intensely. Therefore, first of all, parents should be informed about the toxic effects of endocrine disruptors on children, and it should be emphasized that families should pay attention to the signs indicating the type of plastic when using plastic materials. In addition, families should not consume packaged food, ready-made water or beverages, use plastic storage containers in the daily care of their children, and if used, they should not put hot food in these containers, should not heat food, should not use plastic household items, flooring and plastic children's toys. Keywords: Children attention deficit hyperactivity disorder, bisphenol A, phthalates