Objective: To detect lead in samples that are at least 1% lead.
Materials and Methods/Procedures: 0.5 ml of 6M nitric acid was placed in
a test tube, 1.0 g of sample paint chips were added, and the test tube was
placed in a beaker of boiling water for 15-20 minutes to dissolve the lead.
10-20 ml of acetic acid was placed on pottery, the pottery was allowed to
stand for an hour, the solution was poured into a test tube, which was then
placed in a beaker of boiling water for 5-10 minutes. The test tubes were
carefully removed and 7-8 ml of fresh 1% sodium sulfite was added to
neutralize additional acid. The samples were allowed to cool, the
precipitate was allowed to settled ,and a couple of drops of 0.1 M
potassium iodine were added to the samples. A raw egg was separated, the
white was placed in a beaker, 10 drops of the white were placed in a watch
glass, 1 ml (20 drops) of the lead acetate solution was applied, and
results recorded. Three people collected 1 ml of saliva in clean test
tubes, the saliva was combined in a 25 ml graduated cylinder, the test
tubes were rinsed with 5 ml of pH 7 buffer solution, poured into the
graduated cylinder with the saliva, enough pH7 buffer was added until the
volume was 25 ml, and the mixture was stirred well. Five clean test tubes
were labeled, 5 ml of the saliva solution was added to tubes #2-5, while 5
ml of pH 7 buffer was placed in tube #1. 1 ml of the lead acetate
solution was added to tube #3-5, and observed for a reaction after 10
minutes, while 1ml of pH buffer was added to tubes #1, #2 and #4. Next,
10 ml of 1% starch solution was added to tubes #1, #4, and #5, and observed
after 10 minutes, while 10 ml of distilled water was added to tubes #2 and
#3. 5 ml of iodine solution was added to all 5 tubes, and after 15
seconds, the reactions were observed and recorded, and the solutions were
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