Ecotoxicology and Environmental Safety (Jul 2022)
Combined toxicity of air pollutants related to e-waste on inflammatory cytokines linked with neurotransmitters and pediatric behavioral problems
Abstract
E-waste usually refers to the discarded electrical or electronic equipment that is no longer used. Informal e-waste recycling methods, such as burning, roasting, acid leaching, and shredding, had resulted in serious air pollution, which is a prominent risk factor for children’s health. However, the combined toxicity of air pollutants on children’s behavioral health remains unclear. This study collected data on air pollution exposure, calculated the average daily dose (ADD) based on these air pollutants for children in Guiyu (e-waste group, n = 112) and Haojiang (reference group, n = 101), then assessed children’s behavioral health using the Strengths and Difficulties Questionnaire (SDQ), and further estimated the associations of ADD, inflammatory cytokines, neurotransmitters, and children’s behavioral problems. Compared with Haojiang, Guiyu has poorer air quality and higher levels of ADD, inflammatory cytokines (such as IL-1β, IL-6, and TNF-α), neurotransmitters (such as DA and SP), and SDQ scores, but lower levels of serum neuropeptide Y (NPY) levels. Spearman correlation analyses indicated that there were significant relationships among inflammatory cytokines, neurotransmitters, and behavioral scores. Multiple linear regression analyses showed that each unit increase in ADD was associated with serum levels of DA and SP, the serum NPY subsequently changed by B (95% CI): 0.99 (0.14, 1.84) nmol/L, 0.25 (0.08, 0.42) ng/mL, and − 0.16 (−0.26, −0.05) ng/mL, respectively. After adjustment for confounders, logistic regression analyses suggested that with each one-fold increase in ADD was associated with the risk of emotional symptoms [OR (95% CI): 18.15 (2.72, 121.06)], hyperactivity-inattention [13.64 (2.28, 81.65)] and total difficulties [8.90 (1.60, 49.35)] and prosocial behavior [− 7.32 (−44.37, −1.21)]. Taken together, this study demonstrates that combined exposure to air pollutants may alter the levels of inflammatory cytokines and serum neurotransmitter to subsequently impact behavioral health in children.