Science Buddies: "Ask an Expert"

Hi all,

I am doing a science experiment testing the effects of phytoremediation. I am using Indian mustard seeds in copper sulfate solutions to see how the seeds reduce the concentration of copper. The only problem is that I don't know what concentrations of copper to use. At first I wanted to use concentrations of 0,50, 100, and 150 ppm as indicated in this study http://research.sc.chula.ac.th/31-1e/pa ... iyanan.pdf but I can't find a test kit that measures that high.

Most test kits online only measure up to 10 ppm. Should I just lower my copper concentrations to 0, 1, 2, and 3 ppm? I'm worried that these low concentrations will not yield good data. Can anyone please help me find a good way to accurately measure the copper concentrations without breaking the bank? I would really appreciate it.
Thanks!!

Hi arigenius,

Did the study you are referring to see measurable results between 0 and 50 ppm? (I can't get the link to work, unfortunately). If they didn't see an effect between 0 and 50 ppm, then it is unlikely you will see an effect with 0, 1, 2, and 3 ppm. But, if the authors did see an effect, then it may be possible that you will see one at much lower concentrations. I would suggest doing the experiment to find out.

The EPA's maximum contaminant level goal for copper in drinking water is 1.3 ppm (see http://water.epa.gov/drink/contaminants ... copper.cfm), so reducing levels even from 3 ppm to 1 ppm may be an interesting result.

There definitely are other ways of measuring copper, but the ones I can think of are all quite expensive and require special equipment. It's possible that another Expert may chime in with a different, inexpensive way of measuring copper at the 10s to 100s of ppm level.