National Commission for Protection of Child Rights (NCPCR) has expressed concern at the incidents of injectable substance abuse seen among children in Tamil Nadu. Commission member R G Anand told reporters here on Friday that a low cost pain killer tablet given to cancer patients is mixed with water and injected by the children. "We were shocked to see a group of four boys inject it in Pudukottai and a probe revealed that the tablets were supplied by a pharmaceutical products supplier in Tirupur," he said. The NCPCR member said that the cost of the substance is as low as Rs 12 to Rs 15 per person and is even shared by a group of four boys, making it easily available to students and street children. "The effect of the injections lasts up to 24 hours. Supply of the tablets was in quantities of 2,500 to 3,000 and requirement to supply ratio was 1:100," he added.