Investigation of Copper Toxicity in Drinking Water Taken from Macquarie University Fountain - Coursework Example

Investigation of Copper Toxicity in drinking water taken from Macquarie University Fountain Introduction The human body consists of more than 70% water and is one of the most important elements. People n Australia including students at the Macquarie University drinks natural water. Students in the university drink water from the bubbler which has been set there. Water contains chemical both found naturally and some chemical arises when water is chemically treated with a sterilizer. Despite the chemicals found in water the percentage of chemical is very low which makes it suitable for consumption. We as individuals are exposed to different type of chemicals which was witnessed when a student drank water from a bubbler which was not used frequently. The examination through a doctor showed signs of high copper level. Some studies point that consumption of beverages having high copper content results in nausea, vomiting and diarrhea. Copper is required in the human body but large quantities can be fatal. One of the main source of copper is through water going through the copper wires which have been corrugated. Macquarie University has a presence of large number of copper wires in their internal plumbing and is used to transport water to kitchen and other areas. This could be a reason for the water being contaminated by copper in Macquarie University. The World Health Organization prescribes the limit to be 2.0 mg/l and increase above it can be fatal for the human body. Corrosion in pipes occur due to the type of material that has gone to make the pipe, the age of the pipe, the sanitation and other factors resulting in corrosion. Copper corrosion thereby gives blue stain and gives a bitter taste to the water we drink. Research carried in this direction will help to understand the copper corrosion found in water taken from the university fountain. The three factors which affect copper corrosion are temperature, pH and hardness. This research thereby looks towards first identifying the hardness of the water through EDTA titration. Secondly, to find the concentration of copper solution in the water AAS is adopted. The other reason is the pipe itself which might be exposed to zinc water or electric wire or might be open and in contact with the ground. Experimental Sample Spot Total of 48 samples were collected from different locations in the university which used water fountain and it was done thrice at different time Sample Preparation Total of 48 samples were collected from different locations in the university which used water fountain and it was done thrice at different time were brought to the laboratory for analysis Hardness in water was tested through EDTA titration Reagents EDTA Solution In this method Di-Sodium salt of EDTA has been dried at 80°C to remove the excess moisture. 0.9 g of EDTA is carefully measured and then carefully transferred to a 250 ml volumetric flask where 2 – 3 ml of pH 10 ammonia buffer is provided. The deionized water in put into the flask and allowed to dissolve. The entire process takes around 15 minutes Procedure 50 ml of water from the tap in put in a 250 ml Erlenmeyer flask. Titrate is added in the method provided above. One trial has to be performed. The 1 ml of ammonia buffer is provided through a graduated cylinder of 10 ml. The heat at this point results in a condensation to form on the inside rim of the flask. Then a few drops of indicator are added. It the colour of the solution changes blue then there is no measurable calcium or magnesium in the solution. If the colour of the solution remains red or violet then the titrating method starts with the EDTA solution. This process is done till the traces of red or violet colour disappear. This makes it necessary to ensure that the titrate process is done slowly so that the process doesn’t do more titration then required. Concentration of copper content was done through AAS Experimental Reagents The materials that were used in the experiment included HPCL-grade water, nitric acid and copper standard solution for atomic absorption spectroscopy. This helped to create different reagent samples of the stock solution where 2% (w/v) nitric acid in HPLC-grade water was found through the AAS solution. The method also ensured that the blan solution used copper analyte and reagent consisted of HPLC- grade water. Instruments & Apparatus To find out the concentration of copper content in the water GBC 932AA atomic adsorption spectrometer (AAS) operating with an air acetylene flame were used. The AAS instrument was used and equipped with copper hollow cathode lamp and acetylene fuel. The wavelength was identified to be 324.7 nm. The copper concentration level detected was in the range of 0.2-5 mg/L with a 0.02 mg/L limit of detection Procedure The curve has been generated through a stock solution. To prepare 1L of stock solution 1 g of electrolyte copper was dissolved in 5ml of redistilled HNO3 and was further diluted with distilled water. To get the calibration curve various level of stock dilutions are prepared. A sample solution is also developed to compare the calibration curve and to find out the copper content. It is then combined in the ratio 1:1 and is then redistilled with HNO3 pH for less than 2. 3 ml of acid was found to be sufficient. The volume is then adjusted to determine the concentration level of copper. The stock solution is then run so that a calibration curve can be made for different level of absorption. This helps to find out the concentration of copper from the calibration curve that has been generated. Result & Discussion Data for copper release for different pH, temperature and hardness Influence of temperature The result as seen in the below figure shows that copper is not affected by temperature as the concentration is random as seen from the chart below. This highlights no relationship between temperature and concentration of copper which was seen in the outcome as it didn’t affect the chemical reaction of water Figure 1: Graph showing the concentration of each water sample versus temperature. Influence of pH The pH concentration of water has been plotted for every corresponding data in figure 2 which helps to find out the alkalinity of water. The pH in rain water is between 5.5-6.0 and natural water has pH 6.5-8.5. It is seen that a pH of below 5 is unsafe. The sample collected showed a pH of more than 8 and was in the range of 8 – 10 hence was fit for consumption. Figure 2: Graph showing the concentration of each water sample versus pH Influence of hardness Hardness in water is characterized by divalent metals like calcium and magnesium and looks towards leaching metals form the pipes and results in a deposit to be formed inside the pipe. The hardness and softness in then adjusted. The finding shows that there was no relationship between the concentration of copper and hardness as seen below Figure 3: Graph showing the concentration of each water sample versus hardness Influence of Time The difference in the timing of collection of water in the morning and evening showed a slightly different result as it was seen that the concentration of copper was slightly higher in the morning as compared to the water collected in the evening. Conclusion The research was carried out in Macquarie University to find the concentration of copper in drinking water and three factors hardness, pH and timing were used because a student had developed symptom after drinking the water. It showed that the concentration of copper from building E8C, E8A, E5B, W5A, C5A, CB8A and C5C were higher than the WHO limit of 2.0 mg/L. This also showed that the corrosion in pipe was the main reason for copper content and can be corrected by using water softener or repairing the pipe. It also showed that pH, temperature and hardness were not the reason for the copper content. Read More