Copper pipes, new and old, PVC pipes, Brass pipes, all 6 inch long, plugged at one end; Copper reagent from Hach Co. (CuVer reagent); Color comparator; Color wheel; Sample holder (Hach Co.); pH paper; Safety Glass. First, the pipes were numbered and placed on the rack. Then they were filled with tap water (pH 6) and water of pH 4 and 3 (by adding nitric acid). Every 2-3 days, 5 mL aliquots of the water samples were taken out. each sample was mixed with a pillow of the CuVer reagent and shaken. The intensity of the purple color thus generated was then compared with the purple hue on the Hach color wheel. Since the intensity of the purple color is proportional to the concentration of copper in the water sample, the amount of copper leached out after a certain period of time was directly determined from this experiment.
The results demonstrated that copper did leach out of the copper pipes and acidic water enhanced the rate of leaching. Old copper pipes showed more contamination than the new pipes while brass pipes showed moderate amounts of copper in the water.
The amount of copper in drinking water does increase to a significant level (above the EPA standard of 0.3 ppm) upon standing in copper pipes overnight. The concentration of copper goes up with days and hence water should be drained especially after no usage of the faucets for a long time (like vacations). Such problems will be more prominent in houses with old copper pipes. Excess copper could cause gastrointestinal disturbances, nausea and other physical disorders. People with Wilson's disease would be especially susecptible.
This project is about how copper is leached out of copper pipes and contaminate our drinking water.
Science Fair Project done By Shamik Mascharak