Blood Lead Levels in Children Aged 0 to 6 Years in China: A National Survey

Background : Lead exposure is a major environment-related disease that severely endangers childhealth. However, the magnitude of lead exposure among children in China remains unclear at thenational level. We conducted a national survey of blood lead levels in children aged 0 – 6 years.Methods :From May 2013 to March 2015, we used a multi-stage clustered random samplingapproach to select 90 districts/counties in 15 provinces across the country. Parents were interviewed,and the blood lead levels in children were tested using graphite furnace atomic absorptionspectrometry.Findings: A total of 31,373 children with valid samples were included. The median and geometricmean blood lead levels were 26.4 and 26.7μg/L, respectively. The geometric mean blood lead levelof children in Shanghai was the lowest (18.8μg/L), and that in Guangdong was the highest(33.7μg/L). The blood lead level of the children in the central region was the lowest (25.5μg/L)compared with the eastern region (26.6μg/L) and the western region (27.3μg/L). The geometric meanblood lead level of the children in large cities (24.2μg /L) was lower than that of the children insmaller cities (27.4μg /L) and rural areas (27.5μg/L). Boys had a higher lead level than girls (27.2 vs.25.9μg/L, p<0.0001). Children aged 36-84 months had a slightly higher lead level than children aged0-36 months (25.7 vs. 27.9μg/L, p<0.0001).Interpretation: The blood lead levels in children aged 0-6 years in China showeda dramatic decline compared with the past few decades. The blood lead levels of children were thelowest in the central region and among urban children in big cities. The blood lead levels of boyswere higher than those of girls, and the lead levels were much higher in 36- to 84-month-old childrenthan in 0- to 36-month-olds.