Toxic elements and heavy metals concentrations in playground of elementary schools of Brandon, Manitoba, Canada

Chemical safety of school playgrounds is very important for the health and well-being of students and it is expected that level of heavy metals [including toxic elements] be below acceptable [non-toxic] levels. The risk from accidental consumption of potentially toxic elements in playground soils is of concern to children’s health. Concentration of heavy metals is a very important factor in assigning type of land use. For example, Canadian Council of Ministers of the Environment [CCME] has published soil quality guidelines to help protect environmental and human health. These guidelines identify 4 types of land use in Canada: agricultural, residential/parkland, commercial, and industrial. Different concentrations of heavy metals are suggested for each land use.

A total of 73 samples were collected from playgrounds of 16 elementary schools in Brandon, Canada and analysed for major and light elements [Fe, Ti, Ca, K, Al, P, Si, Cl, S, Mg] as well as trace and heavy metals [As, Ba, Cd, Cr, Cu, Pb, Mn, Ni, Se, U, V, Zn]. The elemental relationships in these samples show that the data sets were predominantly influenced by natural geologic element dispersion and accumulation processes. Anthropogenic sources generally enrich individual [or small number of] elements and, as a result, distributions are disturbed and skewed towards higher values in natural systems. Lower values are commonly free from anthropogenic influences. This research shows that As, Ba and Cu are the only heavy metals in playgrounds of some schools in Brandon that are higher than, or close to, the values suggested by the Canadian soil quality guidelines.