This news release is available in French.
We know that babies and young children often put non-food items in their mouths, a behaviour that occasionally leads to swallowing of foreign objects. Metallic toys and low-cost jewelry often contain toxic substances such as lead and cadmium. Do these objects present a health risk for young children?
To answer this question, Gérald J. Zagury, a professor in the Department of Civil, Geological and Mining Engineering at Polytechnique Montréal, and Mert Guney, a former doctoral student under Professor Zagury's supervision, examined metals contamination in a selection of 72 toys and jewelry items purchased on the North American market. They then conducted in vitro tests on 24 samples by recreating the biochemical conditions of the gastrointestinal system in the laboratory in order to get an accurate answer.
"We observed that cadmium and lead contamination, both very toxic metals, are a major problem, especially when it comes to metallic jewelry and toys. Copper, nickel, arsenic and antimony were also present in some samples," explains Professor Zagury. In-depth tests showed that the metals can be mobilized into the digestive fluids once contaminated items are ingested. The researchers also observed that the mobilized quantities of cadmium, lead and nickel from some samples exceeded the safety threshold levels that a child can be exposed to without suffering acute harmful effects (abdominal pain, nausea, vomiting and diarrhea) or variable chronic effects depending on the contaminant. It must be noted that chronic ingestion of lead and cadmium can have irreversible effects on a child's intellectual development.
The results presented in this study are part of Mert Guney's doctoral thesis and were recently published in the American Chemical Society's (ACS) reputed scientific journal, Environmental Science & Technology. The article was selected to appear in ACS' Editors' Choice; the open-access article can be read at
The study was made possible thanks to the financial support of the Natural Sciences and Engineering Research Council of Canada (CRSNG).
Reference: Guney M, Zagury GJ (2014). Bioaccessibility of As, Cd, Cu, Ni, Pb, and Sb in Toys and Low-Cost Jewelry. Environmental Science & Technology, published online, DOI: 10.1021/es4036122. 48 (2), pp 1238-1246.
About Polytechnique Montréal
Founded in 1873, Polytechnique Montréal is one of Canada's leading engineering teaching and research institutions. It is the largest engineering university in Québec for the size of its graduate student body and the scope of its research activities. With over 41,400 graduates, Polytechnique Montréal has educated nearly one-quarter of the current members of the Ordre des ingénieurs du Québec. Polytechnique provides training in 15 engineering specialties, employs 248 professors and has more than 7,500 students. It has an annual operating budget of over $200 million, including an $82-million research budget.