Determinants of blood lead levels in children: a cross-sectional study in the Canary Islands (Spain).
ABSTRACT The adverse effects of lead exposure on children are well known. Low blood lead levels (BLL) produce neurodevelopmental delay and cognitive disorders. However, since BLL thresholds for adverse effects on children's health are not known, the children population at risk of excessive lead exposure still has to be identified. This study was aimed at evaluating BLL in a children population of Gran Canaria (Canary Islands, Spain). Up to our knowledge, this is the first study to report on BLL in this population. Lead was identified and quantified in blood samples of 120 children, by means of Graphite furnace atomic absorption spectrometry (GFAAS). Lead was undetected in 80% of samples; BLL was 1 to 5 μg/dl in 15% of samples, and higher than 5 μg/dl in more than 4% of samples. BLL values in the evaluated children were low and similar to those described for other populations in Western countries. However, samples with the highest contamination (those in percentile 95) reached BLLs as high as 5.2 μg/dl. Positive associations were found between BLL and recent immigration (children adopted from non-western countries), and between BLL and parental smoking in children with low weight at birth. Since lead exposure in childhood may be a causative factor in adverse health trends - especially those involving the neurological system - and since threshold values for adverse lead effects are unknown, our finding that around 20% of the studied children had BLL higher than 1 μg/dl are of concern. Enhancing preventive measures for reducing lead exposure in children from the Canary Islands deserves further study.
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ABSTRACT: The exposure of children to lead has decreased in recent years, thanks notably to the banning of leaded gasoline. However, lead exposure remains a matter of public health concern, because no toxicity threshold has been observed, cognitive effects having been demonstrated even at low levels. It is therefore important to update exposure assessments. A national study was conducted, in 2008-2009, to determine the blood lead level (BLL) distribution in children between the ages of six months and six years in France. We also assessed the contribution of environmental factors. This cross-sectional survey included 3831 children recruited at hospitals. Two-stage probability sampling was carried out, with stratification by hospital and French region. Sociodemographic characteristics were recorded, and blood samples and environmental data were collected by questionnaire. Generalized linear model and quantile regression were used to quantify the association between BLL and environmental risk factors. The geometric mean BLL was 14.9μg/l (95% confidence interval (CI)=[14.5-15.4]) and 0.09% of the children (95% CI=[0.03-0.15]) had BLLs exceeding 100μg/l, 1.5% (95% CI=[0.9-2.1] exceeding 50μg/l. Only slight differences were observed between French regions. Environmental factors significantly associated with BLL were the consumption of tap water in homes with lead service connections, peeling paint or recent renovations in old housing, hand-mouth behavior, passive smoking and having a mother born in a country where lead is often used. In children between the ages of one and six years in France, lead exposure has decreased over the last 15 years as in the US and other European countries. Nevertheless still 76,000 children have BLL over 50μg/l and prevention policies must be pursued, especially keeping in mind there is no known toxicity threshold.International journal of hygiene and environmental health 10/2013; · 2.64 Impact Factor