Use of the Rey-Osterrieth Complex Figure Test for neurotoxicity evaluation of mixtures in children D. Rocha-Amador a , M. Navarro b , A. Trejo-Acevedo c , L. Carrizales a , I. Pe ´ rez-Maldonado a , F. Dı ´az-Barriga a , J. Caldero ´n a, * a Departamento de Toxicologia Ambiental, Universidad Auto ´noma de San Luis Potosı´, Mexico b Facultad de Psicologı´a, Universidad Auto ´noma de San Luis Potosı´, Mexico c Centro Regional de Investigacio ´n en Salud Publica, Instituto Nacional de Salud Publica, Mexico 1. Introduction Several approaches can be used to identify high risk populations exposed to mixtures of pollutants, including biomonitoring. In Mexico, we have identified populations living in high risk areas exposed to either fluoride (F), arsenic (As), lead (Pb), p,p 0 - dichlorodiphenyltrichloroethane (p,p 0 -DDT) or polychlorinated biphenyls (PCBs) at levels above those recommended as safe (Rocha-Amador et al., 2007; Carrizales et al., 2006; Caldero ´ n et al., 2001a; Ya ´n ˜ ez et al., 2002; Noren ˜ a-Barroso et al., 1998, 2004, 2007). The sources and pathways of exposure to these toxicants in each area are very different. For example, exposure to F and As occurs through naturally contaminated drinking water; for As and Pb the exposure is primarily through soil and dust deriving from pyrometallurgic nonferrous metal production or mining activity. For p,p 0 -DDT, intake is likely due to diet (fish consumption) or maternal milk in areas where this insecticide was used as a preventive Public Health strategy to control malaria. For PCBs, exposure is likely through the intake of fish. The assessment of health effects in these settings is very complicated due to exposure to mixtures of toxicants but also economical and social dis- advantages. A review of health effects data associated with exposure to the toxicants mentioned above concluded that the Central Nervous System (CNS) effects were the most likely adverse health outcomes. Several authors have reported reduction in Intelligence Quotient (IQ) scores (Li et al., 1995; Zhao et al., 1996; Lu et al., NeuroToxicology 30 (2009) 1149–1154 ARTICLE INFO Article history: Received 3 December 2008 Accepted 8 September 2009 Available online 19 September 2009 Keywords: Neurotoxics Mixtures Rey-Osterrieth Complex Figure Test Visuospatial organization Visual memory Children ABSTRACT The aim of this study was to assess the value of the children’s version of the Rey-Osterrieth Complex Figure Test as a screening test in a population exposed to different mixtures of neurotoxicants. Copy and Immediate Recall scores were evaluated through the test. Children were recruited from three sites; an area with natural contamination by fluoride and arsenic (F–As), a mining-metallurgical area with lead and arsenic contamination (Pb–As) and a malaria zone with the evidence of fish contaminated with dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs). Children aged 6–11 years old, living in one of the three polluted sites since birth were recruited (n = 166). The exposure was evaluated as follows: fluoride and arsenic in urine, lead in blood and DDT, dichlorodiphenyldichlor- oethylene (DDE) and PCBs in serum. To evaluate the test performance, z-scores for Copy and Immediate Recall were calculated. The proportion of children by residence area with performance lower than expected by age (below 1 SD) for Copy and Immediate Recall was in the F–As area (88.7% and 59%) and in the DDT–PCBs area (73% and 43.8%), respectively. In the Pb–As area, the proportion was 62% for both tests. After adjustment, Copy correlated inversely with fluoride in urine (r = 0.29; p < 0.001) and Immediate Recall correlated inversely with fluoride in urine (r = 0.27; p < 0.05), lead in blood (r = 0.72; p < 0.01), arsenic in urine (r = 0.63; p < 0.05) and DDE (r = 0.25; p < 0.05). This study provided evidence that children included in this research are living in high risk areas and were exposed to neurotoxicants. Poor performance in the test could be explained in some way by F, Pb, As or DDE exposure, however social factors or the low quality of school education prevalent in the areas could be playing an important role. ß 2009 Elsevier Inc. All rights reserved. * Corresponding author at: Departamento de Toxicologı ´a Ambiental, Universidad Auto ´ noma de San Luis Potosı ´, Av. Venustiano Carranza 2405, Col. Lomas los Filtros, San Luis Potosı ´, CP 78210, S.L.P. Me ´ xico. Tel.: +52 (444) 826 2354; fax: +52 (444) 826 2354. E-mail addresses: calderoj@uaslp.mx, calderon617@hotmail.com (J. Caldero ´ n). Contents lists available at ScienceDirect NeuroToxicology 0161-813X/$ – see front matter ß 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.neuro.2009.09.003