Prenatal Metal Mixture Concentrations and Reward Motivation in Children
Year: 2019
Type: conference-abstract
Abstract: OPS 38: Effects of metals on child health, Room 114, Floor 1, August 27, 2019, 4:30 PM - 5:30 PM Background: Altered reward motivation in childhood has been linked to hyperactivity and to an increased risk for substance abuse later in life. In children, exposure to neurotoxic metals has been linked to hyperactivity and changes in morphology and connectivity of brain areas supporting reward motivation (i.e., the basal ganglia). The association between metal exposure and reward motivation in children has not been studied. We examined associations between prenatal exposure to a mixture of neurotoxic metals and reward motivation in children using a Progressive Ratio (PR) test. Methods: The PR test was administered to 271 children (132 girls; 6-8 years) from the PROGRESS Study (Programming Research in Obesity, Growth, Environment and Social Stressors) in Mexico City. Children were asked to press a response lever for a nickel reward, one response was required to earn the first nickel and each subsequent nickel required an additional 10 responses. Outcomes included the number of times the lever was pressed and the mean time between lever presses. Maternal blood concentrations of 6 neurotoxic metals (manganese, lead, selenium, cadmium, zinc, arsenic) were measured using inductively-coupled plasma mass spectrometry (ICP-MS) during the 2nd trimester of pregnancy. We performed Weighted Quantile Sum (WQS) regression analyses, stratified by sex, to examine associations between the metal mixture and reward motivation, adjusting for child age and maternal IQ. Results: A higher prenatal metal mixture was associated with more lever presses (ß = 2.85, p = 0.03) and a shorter time between presses (ß = 0.07, p = 0.04) among girls only. Cadmium (~ 35%), selenium (20%), and manganese (17%) were the largest contributors to these associations. Conclusions: Prenatal exposure to a mixture of neurotoxic metals is associated with increased motor responses to obtain rewards in girls. These may be indicative of hyperactivity and heightened reward sensitivity.
Source: Environmental Epidemiology
Authors: de Water E, Curtin P, Bixby M, Gennings C, McRae N, Svensson K, Chelonis J, Schnaas L, Pantic I, Téllez-Rojo M, Wright R, Horton M
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,200
OpenAlex ID: W3083406538