do Nascimento Sabrina Nunes, Charão Mariele Feiffer, Moro Angela Maria, Roehrs Miguel, Paniz Clovis, Baierle Marília, Brucker Natália, Gioda Adriana, Barbosa Fernando, Bohrer Denise, Ávila Daiana Silva, Garcia Solange Cristina
Laboratory of Toxicology (LATOX), Department of Analysis, Federal University of Rio Grande do Sul, Porto Alegre, RS 90610000, Brazil.
Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, RJ 22451900, Brazil.
Int J Environ Res Public Health. 2014 Oct 17;11(10):10806-23. doi: 10.3390/ijerph111010806.
Children's exposure to metals can result in adverse effects such as cognitive function impairments. This study aimed to evaluate some toxic metals and levels of essential trace elements in blood, hair, and drinking water in children from a rural area of Southern Brazil. Cognitive ability and δ-aminolevulinate dehydratase (ALA-D) activity were evaluated. Oxidative stress was evaluated as a main mechanism of metal toxicity, through the quantification of malondialdehyde (MDA) levels. This study included 20 children from a rural area and 20 children from an urban area. Our findings demonstrated increase in blood lead (Pb) levels (BLLs). Also, increased levels of nickel (Ni) in blood and increase of aluminum (Al) levels in hair and drinking water in rural children were found. Deficiency in selenium (Se) levels was observed in rural children as well. Rural children with visual-motor immaturity presented Pb levels in hair significantly increased in relation to rural children without visual-motor immaturity (p < 0.05). Negative correlations between BLLs and ALA-D activity and positive correlations between BLLs and ALA-RE activity were observed. MDA was significantly higher in rural compared to urban children (p < 0.05). Our findings suggest that rural children were co-exposed to toxic metals, especially Al, Pb and Ni. Moreover, a slight deficiency of Se was observed. Low performance on cognitive ability tests and ALA-D inhibition can be related to metal exposure in rural children. Oxidative stress was suggested as a main toxicological mechanism involved in metal exposure.
儿童接触金属可能会导致诸如认知功能受损等不良影响。本研究旨在评估巴西南部农村地区儿童血液、头发和饮用水中的一些有毒金属及必需微量元素水平。对认知能力和δ-氨基乙酰丙酸脱水酶（ALA-D）活性进行了评估。通过定量丙二醛（MDA）水平，将氧化应激作为金属毒性的主要机制进行评估。本研究纳入了20名农村儿童和20名城市儿童。我们的研究结果表明血液铅（Pb）水平（BLLs）有所升高。此外，还发现农村儿童血液中的镍（Ni）水平升高，头发和饮用水中的铝（Al）水平升高。农村儿童也存在硒（Se）水平缺乏的情况。与无视觉运动发育不成熟的农村儿童相比，有视觉运动发育不成熟的农村儿童头发中的铅水平显著升高（p < 0.05）。观察到BLLs与ALA-D活性之间呈负相关，BLLs与ALA-RE活性之间呈正相关。农村儿童的MDA水平显著高于城市儿童（p < 0.05）。我们的研究结果表明农村儿童同时接触了有毒金属，尤其是铝、铅和镍。此外，还观察到硒略有缺乏。农村儿童在认知能力测试中的低表现和ALA-D抑制可能与金属暴露有关。氧化应激被认为是金属暴露所涉及的主要毒理学机制。
