Seasonal Variation of Heavy Metals in Playgrounds of Public Schools within Owerri Metropolis, Imo State, Nigeria

Knowledge of variation in metal concentrations of playground soil in dry and rainy season could assist in controlling metal accumulation in children if playtime is regulated according to seasons. The present investigation was designed to find out the existence and trend of such variation. Thirty six surface soil samples from nine playgrounds of Owerri metropolis were collected during the dry season and rainy seasons of 2012 and 2013 and were digested in Pyrex glassware using nitric acid. Total heavy metal concentration was determined by AANALYST 400 Perkin Elmer absorption spectrophotometer and coefficient of variation was used to categorize variability. Results demonstrated significant seasonality for all five heavy metals with major variability observed between dry and the rainy season. Metal concentrations showed zinc as highest metal in both seasons whereas cobalt was lowest metal with Ni occasionally being lowest in the rainy season. The variation of metals concentrations in playground soil especially in the rainy season may add to the body burden of the children, and therefore reduced hours of play during this season is recommended.