The controversy about the high arsenic content in Lucknow's water has taken a new turn. The contention of M C Saxena, director, Environmental Research Laboratory, that the water contains 10,000 parts per billion (PPB) of arsenic has been refuted by an expert. Dipankar Chakraborti, an authority on arsenic and director of School of Environmental Sciences, Jadavpur University, points out that the quantity of arsenic is only around 3 PPB