Screening for Elevated Blood Lead Levels in Children: Assessment of Criteria and a Proposal for New Ones in France

Abstract

The decline in children’s Blood Lead Levels (BLL) raises questions about the ability of current lead poisoning screening criteria to identify those children most exposed. The objectives of the study were to evaluate the performance of current screening criteria in identifying children with blood lead levels higher than 50 µg/L in France, and to propose new criteria. Data from a national French survey, conducted among 3831 children aged 6 months to 6 years in 2008–2009 were used. The sensitivity and specificity of the current criteria in predicting blood lead levels higher than or equal to 50 µg/L were evaluated. Two predictive models of BLL above 44 µg/L (for lack of sufficient sample size at 50 µg/L) were built: the first using current criteria, and the second using newly identified risk factors. For each model, performance was studied by calculating the area under the ROC (Receiver Operating Characteristic) curve. The sensitivity of current criteria for detecting BLL higher than or equal to 50 µg/L was 0.51 (0.26; 0.75) and specificity was 0.66 (0.62; 0.70). The new model included the following criteria: foreign child newly arrived in France, mother born abroad, consumption of tap water in the presence of lead pipes, pre-1949 housing, period of construction of housing unknown, presence of peeling paint, parental smoking at home, occupancy rates for housing and child’s address in a cadastral municipality or census block comprising more than 6% of housing that is potentially unfit and built pre-1949. The area under the ROC curve was 0.86 for the new model, versus 0.76 for the current one. The lead poisoning screening criteria should be updated. The risk of industrial, occupational and hobby-related exposure could not be assessed in this study, but should be kept as screening criteria.

Blood Lead Level in a Paediatric Population of South-Eastern Spain and Associated Risk Factors

“…In recent years, studies have determined BLL in the Spanish regions of Catalonia, Madrid and the Canary Islands [22][23][24], reporting findings similar to those obtained in other developed countries [11,20]. In the southern region of Andalusia, however, no such study has yet been conducted.…”

“…A recent study [ 10 ] analysed data from refugee children in the USA between 2010–2014, and recorded BLL prevalence >10 µ/dL among 16.7% of the children of Afghan origin and among 3.4% of those from Kenya. In contrast, the reported prevalence in developed countries is around 0.1% [ 11 ].…”

Lead Exposure and Associated Risk Factors among New Migrant Children Arriving in Greece

“…Increased BLLs are more prevalent in immigrant and refugee children, which is interrelated to a number of contributing factors, such as exposure in their native country or during their journey of transition, as well as specific cultural habits or housing conditions that may persist in receptive countries [ 9 ]. Additional risk factors include younger age (<6 years old), low family income, living in old houses, passive smoking, maternal country of origin or exposure to lead during pregnancy [ 9 , 10 , 11 ]. Therefore, CDC recommends that all newly entered migrant children, between 6 months and 16 years of age, within 30–60 days of arrival to the United States should be screened for BLLs [ 9 ].…”

The Risk Factors of Child Lead Poisoning in China: A Meta-Analysis

“…Children, who are still growing, are more likely to be sensitive to the harmful effects of lead [ 6 ]. The diagnostic criteria for child lead poisoning have been revised in some developed countries [ 7 , 8 ]. Currently, the Centers for Disease Control and Prevention in the U.S. recommend a reference level of five micrograms per deciliter to identify children with blood lead levels.…”