Blood lead levels and associated sociodemographic factors among preschool children in the South Eastern region of China

Abstract

Summary Children are especially vulnerable to lead toxicity, and exposure to lead has been linked to poor school performance and delinquency in children and adolescents. Even low-level lead exposure (blood lead level [BLL] lower than 10 µg/dL) can cause intelligence deficit. In China, BLLs in children decreased slightly after the phase-out of lead in gasoline, but few studies have examined the socio-demographic factors associated with BLL above 10 µg/dL. In thus study, we sought to examine the hypothesis that socio-demographic factors predict BLLs. We measured BLLs of 1,344 preschool children (3–5 years old) from the China Jintan Child Cohort Study. Children’s socio-demographics and health statuses, as well as parental socio-demographics, were collected through questionnaire. Multiple regression models were used to explore the association between socio-demographic factors and log-transformed BLLs as well as the relationship between socio-demographic factors and the risk of BLL above 10 µg/dL. We found the median BLL to be 6.2 µg/dL (range: 1.8–32.0 µg/dL), and 8% of children had BLLs above 10 µg/dL. Boys had a higher median BLL (6.4 µg/dL) than girls and were more likely to have BLL above 10 µg/dL (OR=1.77, 95% CI 1.14 –2.74). BLLs increased as children aged, with a median BLL of 6.6 µg/dL among 5-year old children. Children with sibling(s) had higher average BLL and prevalence of BLL above 10 µg/dL than those without sibling(s). Living in a crowded neighborhood was also associated with increased BLLs. Mother’s lower education, father’s occupation (as professional worker), and parental smoking at home were associated with increased BLLs. This study shows that children in this area still have relatively high BLLs after the phase-out of leaded gasoline. Both children’s and parental factors and community condition are associated with increased BLLs. Future efforts are needed to identify other exposure sources and develop targeted prevention strategies.

Risk factors for elevated blood lead levels among children aged 6–36 months living in Greece

“…In agreement with previous studies (Tong et al 1996;Liu et al 2012), toddlers' BLLs were significantly higher than infants in this sample. Exposure to lead while growing up might be enhanced because of increasing activity level, time on the floor and mouthing and/or pica (Faustman et al 2000).…”

“…To the opposite, in a study conducted in China, boys had higher levels attributed to behavioural differences (Liu et al 2012). …”

The blood lead levels of outpatients aged 1–18 years from Lu’an, China, 2012–2014

“…This was consistent with previous studies [3,20,22,23,26]. The trends might be the comprehensive effects of several risk factors for lead exposure.…”

“…Previous studies showed that the BLLs of boys were significantly higher than that of girls [3,[20][21][22]. This is thought to be the results of more outdoors activities of boys that leading to more chances of lead exposure.…”

Factors Associated With Elevated Blood Lead Levels in Children

“…Another important potential exposure of lead is likely to be lead dust from parents' work clothing which can be later ingested or inhaled by children at home [9]. However, in the present study we did not find occupation or other parental attributes determining the BLL in children, as also reported by other investigators [10][11][12].…”