knisely ret poster_
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Drinking water & Lead Contamina2on Kari Knisely1, Aus2n Atkins2, Jeff Cunningham3
1. Sligh Middle School; 2. Department of Civil & Environmental Engineering, University of South Florida 3. Department of Civil & Environmental Engineering, University of South Florida
For more informa+on about the program visit: h5p://wareret.net. The Water Awareness Research and Educa+on (WARE) Research Experience for Teachers (RET) is funded by the Na+onal Science Founda+on under award number 1200682.
Abstract
Objec2ve
Background
Approach
Results
References
Conclusions
While traveling to Madagascar, USF iden+fied a major health risk for the residents of the under developed third world country. The most common source currently used in most villages to retrieve drinking water is being made out of melted lead. The assump+on is that the level of lead found in their drinking water pumped from these units contain an unhealthy concentra+on of lead posing even more serious health risks to the country already struggling to survive many water borne illnesses. USF is seeking to iden+fy which method would be most efficient yet effec+ve to use in the field where electricity is usually not available.
To compare results given by 3 different methods on the 7 different lead concentra+on levels in drinking water and conclude which method is most effec+ve to be used in the field in Madagascar.
Standard Levels
Method 1 AA
Method 2 ASV
Method 3 Field Kit-‐ Colorimeter w/ HACH Chemicals
Method 3 Field Kit – Colorimeter w/ Leadquick Chemicals
1 mg/L TBA Not in range Not a5empted Not aWempted 150 μg/L TBA Not in range 123 100, 55, 75 100 μg/L TBA 95 Not a5empted 63, 55, 43 50 μg/L TBA 44, 42, 49, 44 30 34, 29, 32 10 μg/L TBA 7, 3 Not a5empted <3, <3, <3 5 μg/L TBA 6, 5 Not a5empted <3, <3, <3 2 μg/L TBA 14, 20 Not a5empted Not aWempted 0 μg/L TBA 48, 14 Not a5empted <3, <3, <3
7 Concentra+on Levels made to be tested • 1 mg/L • 150 μg/L • 100 μg/L • 50 μg/L • 10 μg/L • 5 μg/L • 1 μg/L
In Madagascar only 47% of the popula+on has access to clean drinking water. In the Eastern part of the island, local ar+sans dig shallow drinking water wells and install locally manufactured pumps. Lead from old ba5eries is used for various parts of these pump systems as floats and as solder on the screen in contact with the water. Preliminary sampling of wells in 2010 and analysis for lead using ICP-‐MS at the University of South Florida (USF) indicated that there were some wells with lead levels above safe limits of 10 ug/L as set by the World Health Organiza+on. Through the Master’s Interna+onal program in Civil and Environmental Engineering at USF, our team currently has a member on the ground in Madagascar who wishes to test these levels in the field. This research compared the effec+veness of different analy+cal methods to measure the level of lead contamina+on in drinking water. The mobile/portable analy+cal methods include Anodic Stripping Voltammetry (ASV) and Colorimetry with various reagents for color development. Analysis via lab based methods like the Graphite Furnace Atomic Absorp+on Spectroscopy (GFAAS) were used to compare with the field based kits. The results from this work will be used to iden+fy the most suitable method of analysis for field measurements of lead in drinking water in Madagascar.
3 Methods tested 1. Atomic Absorp+on Spectroscopy (AAS) 2. Anodic Stripping Voltammetry (ASV) 3. Field Kit -‐ Colorimeter
u The AA requires electricity, gas, and is not a mobile method u The ASV was extremely self explanatory, accurate, the fastest
method, lightweight and mobile requiring 4 AA ba5eries u The Colorimeter was not consistent in its readings, the chemical
tes+ng process was extremely complicated and +me consuming, but was very lightweight and mobile requiring ba5eries.
The table below demonstrates the readings each method displayed each 5me it was tested. The closer to the standard the more accurate the test.
u All photos taken from google images or personal camera
Aker researching the different methods displayed in the table, the ASV has proven to be consistent in its results while the Colorimetry methods have been very inconsistent. The Anodic Stripping Voltammetry (ASV), clearly is the best and most reliable method for accurate readings of lead contamina+ons less than 100 μg/L. It is unclear at this +me, what method is most accurate and recommended for concentra+on levels over 100 μg/L, but will con+nue to be researched. The ASV is lightweight, easy to use, and does not require electricity as well as fairly accurate when used to test the lead levels in the standards. At this +me, it will be recommended that USF select the ASV as the measurement method to be used in the field in Madagascar to measure the lead concentra+on levels in the drinking water supplies.