A case of lead poisoning due to snooker chalk

Heavy metals in toys and low-cost jewelry: critical review of U.S. and Canadian legislations and recommendations for testing

High metal contamination in toys and low-cost jewelry is a widespread problem, and metals can become bioavailable, especially via oral pathway due to common child-specific behaviors of mouthing and pica. In this review, the U.S., Canadian, and European Union (EU) legislations on metals in toys and jewelry are evaluated. A literature review on content, bioavailability, children's exposure, and testing of metals in toys and low-cost jewelry is provided. A list of priority metals is presented, and research needs and legislative recommendations are addressed. While the U.S. and Canadian legislations put emphasis on lead exposure prevention, other toxic elements like arsenic and cadmium in toy materials are not regulated except in paint and coatings. The EU legislation is more comprehensive in terms of contaminants and scientific approach. Current toy testing procedures do not fully consider metal bioavailability. In vitro bioaccessibility tests developed and validated for toys and corresponding metal bioaccessibility data in different toy matrices are lacking. The U.S. and Canadian legislations should put more emphasis on metal bioavailability and on other metals in addition to lead. A two-step management approach with mandatory testing of toys for total metal concentrations followed by voluntary bioaccessibility testing could be implemented.

Emerging aspects of assessing lead poisoning in childhood

This review covers the epidemiology of lead poisoning in children on a global scale. Newer sources of lead poisoning are identified. The methods that are used to assess a population of children exposed to lead are discussed, together with the ways of undertaking an exposure risk assessment; this includes assessing the time course and identifying sources of lead exposure. Human assessment measures for lead toxicity, such as blood lead concentrations, deciduous tooth lead, and use of zinc protoporphyrin estimations are evaluated. The role of isotopic fingerprinting techniques for identifying environmental sources of exposure is discussed. Among emerging data on the cognitive and behavioral effects of lead on children, the review considers the growing evidence of neurocognitive dysfunction with blood lead concentrations even below 10 µg/dl. The challenge of assessing and explaining the risk that applies to an individual as opposed to a population is discussed. Intervention strategies to mitigate risk from lead are examined together with the limited role for and limitations of chelation therapy for lead. Lessons learned from managing a population lead-dust exposure event in Esperance, Western Australia in 2007 are discussed throughout the review.

Birth weight, subsequent growth, and cholesterol metabolism in children 8-12 years old born preterm

AIMS

To test the hypothesis that plasma lipids, lipoproteins, and markers of cholesterol biosynthesis (lathosterol) and absorption efficiency (campesterol) in children aged 8-12 years are related to birth size and subsequent growth.

METHODS

A total of 412 girls and boys weighing less than 1850 g at birth were studied. Birth weight, gestation, and weight at 18 months were recorded and followed up at 8-12 years. Plasma total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, apolipoprotein A1, apolipoprotein B, triacylglycerol, lathosterol, and campesterol were measured.

RESULTS

Birth weight for gestational age was positively related to plasma campesterol, and remained so after adjusting for current body size or fatness. Birth weight was negatively related to current plasma lathosterol but only after adjusting for current body size or fatness. For both lathosterol and campesterol the significant relation with birth size adjusted for current size indicates that the change in size between these points (postnatal upward centile crossing) was influential. These relations were absent for total cholesterol, lipoproteins, apolipoproteins, and triacylglycerol.

CONCLUSION

Preterm children who were smaller for gestational age at birth had lower predicted cholesterol absorption efficiency 8-12 years later. Among children of the same current size, predicted endogenous cholesterol synthesis was higher and cholesterol absorption efficiency lower in those who showed the greatest increase in weight centile between birth and follow up. This finding was not confined to children with the smallest birth weights for gestational age. We suggest that both fetal and childhood growth relate to programming of cholesterol metabolism in children born preterm.