Sir: With summers around the corner, children have already started treating themselves to ice-lollies and ice-balls. But many of the vendors stationed outside school campuses sell sub-standard ice-lollies that result in incidences of chest and throat infection among children. The use of artificial colour in ice-lollies and ice balls is injurious to health and children are more vulnerable to infections due to weaker immunity systems. Perhaps schools can encourage students to minimise consumption of such unhygienic and harmful products. Parents should also keep a check!SUMAYYA KHANLahore