Contamination of Drinking Water with Lead (Pb) due to Supply Pipes

Lahore, an ancient city of Pakistan, faces a huge sprawl of old and new buildings. It is not only threatened with depleting water table but also contamination of the available water with highly toxic pollutants. Lead poisoning results in neurological, teratogenic and possibly-carcinogenic effects. The main factors governing the solubility of the protective Lead carbonate layer in drinking water supplying pipes i.e. pH, temperature, water stagnation time in pipes and age of sampling house were taken into consideration. The objective was not to obtain a precise description of each individual situation or highlighting the Lead exposed areas as Lead corrosion is related to particular plumbing system and not the entire locality. A total of 400 drinking water samples were randomly collected from 200 houses in 20 localities of Lahore. Information on consumer behavior and nature of plumbing system was gathered through questionnaire. Samples were analyzed for their physical parameters andthen run on atomic absorption spectrophotometer for Lead detection. Results obtained were statistically analyzed and compared with the guideline values.