Hong Sun1, Wen Chen2, Dongyue Wang3, Yinlong Jin4, Xiaodong Chen5, Yan Xu6, Lei Huang7. 1. Jiangsu Provincial Center for Disease Control and Prevention, Jiangsu Road 172, 210009 Nanjing, PR China. Electronic address: njmu_sunhong@hotmail.com. 2. Nanjing Medical university, Hanzhong road 140, 210029 Nanjing, PR China. 3. Changshu Provincial Center for Disease Control and Prevention, Fuyang Road 6, Changshu 215500, Jiansu, PR China. 4. Chinese Center for Disease Control and Prevention, Nanwei Road 29, Beijing 100021, PR China. 5. Jiangsu Provincial Center for Disease Control and Prevention, Jiangsu Road 172, 210009 Nanjing, PR China; Nanjing Medical university, Hanzhong road 140, 210029 Nanjing, PR China. 6. Jiangsu Provincial Center for Disease Control and Prevention, Jiangsu Road 172, 210009 Nanjing, PR China. 7. State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Xianlin Avenue 163, Nanjing 210023, PR China. Electronic address: huanglei@nju.edu.cn.
Abstract
OBJECTIVES: Examine the relationship between blood lead concentration and children's intelligence quotient (IQ) in Chinese children 8-12 years old. PARTICIPANTS AND METHODS: This is a cross-sectional study, and participants included 446 children from three primary schools in Jiangsu, China. We collected environmental and genetic information from questionnaires. Blood lead (Pb), manganese (Mn), cadmium (Cd) and selenium (Se) concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS). IQ was assessed using the Combined Raven's Test and then converted to a standard IQ score according to Chinese children's norm. Morning urine samples were collected to measure retinol binding protein (RBP). RESULTS: The average blood lead concentration was 33.13 μg L(-1) (geometric mean), and the blood lead concentration (BoxCox transform) was inversely and significantly associated with IQ (r=-0.11, p=0.02). The geometric mean of blood Mn, Cd and Se was 7.02 μg L(-1), 0.18 μg L(-1) and 94.77 μg L(-1), respectively. Blood Mn, Cd and Se showed no association with IQ, but all of them associated with urinary RBP. Urinary RBP was identified as a new factor associated with IQ (β=-6.49, p=0.011). CONCLUSIONS: Urinary RBP was recognized as a new indicated factor associated with children's IQ. Mn, Cd and Se exposure might affect urinary RBP concentration and further IQ. Findings also support that blood lead concentrations in 8-12 years old children, even <44 μg L(-1), have a negative association with IQ.
OBJECTIVES: Examine the relationship between blood lead concentration and children's intelligence quotient (IQ) in Chinese children 8-12 years old. PARTICIPANTS AND METHODS: This is a cross-sectional study, and participants included 446 children from three primary schools in Jiangsu, China. We collected environmental and genetic information from questionnaires. Blood lead (Pb), manganese (Mn), cadmium (Cd) and selenium (Se) concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS). IQ was assessed using the Combined Raven's Test and then converted to a standard IQ score according to Chinese children's norm. Morning urine samples were collected to measure retinol binding protein (RBP). RESULTS: The average blood lead concentration was 33.13 μg L(-1) (geometric mean), and the blood lead concentration (BoxCox transform) was inversely and significantly associated with IQ (r=-0.11, p=0.02). The geometric mean of blood Mn, Cd and Se was 7.02 μg L(-1), 0.18 μg L(-1) and 94.77 μg L(-1), respectively. Blood Mn, Cd and Se showed no association with IQ, but all of them associated with urinary RBP. Urinary RBP was identified as a new factor associated with IQ (β=-6.49, p=0.011). CONCLUSIONS: Urinary RBP was recognized as a new indicated factor associated with children's IQ. Mn, Cd and Se exposure might affect urinary RBP concentration and further IQ. Findings also support that blood lead concentrations in 8-12 years old children, even <44 μg L(-1), have a negative association with IQ.
Authors: Donna J Coetzee; Patricia M McGovern; Raghavendra Rao; Lisa J Harnack; Michael K Georgieff; Irina Stepanov Journal: Environ Health Date: 2016-08-30 Impact factor: 5.984