1. Central American Institute for Studies on Toxic Substances (IRET), Universidad Nacional, Heredia, Costa Rica
2. Institute of Environmental Medicine (IMM), Karolinska Institutet, Stockholm, Sweden
3. >Hospital San Juan de Dios, Social Security of Costa Rica (CCSS), San José, Costa Rica
4. Clínica de Santo Domingo de Heredia, Social Security of Costa Rica (CCSS), Santo Domingo de Heredia, Costa Rica
5. Development of Health Services, Social Security of Costa Rica (CCSS), San José, Costa Rica
6. School of Public Health, University of California at Berkeley, Berkeley, CA, USA
7. Department of Neurology, Emory University, Atlanta, GA, USA
8. Rollins School of Public Health, Emory University, Atlanta, GA, USA