KOLKATA: Paediatric cancers are on the rise and environmental pollution may have a lot to do with it, say experts. According to the Indian Council for Medical Research (ICMR), a decade back, childhood cancers were 2.5% of the total number of cancer cases. Today, they add up to 5.5%. Tata Memorial Centre in Mumbai's Parel area alone treats 2,000 new pediatric cancer cases annually.