Phytoremediation pollutant

[night70]

Hi, this year I want to do a project involving phytoremediation, but because I only have access to a school lab, I'm really unsure of how I'm going to do the project. I found a lot of abstracts online about professional experiments that have been done involving phytorememdiation, but they all seem to involve substances that are too dangerous to handle in a high school lab, like phenols or PAHs.
Also, many of the plants I found might not be practical for a small-scale experiement, like poplar trees. I have a list (about 10-15) of more practical candidates though, such as duckweed, grasses, barley, alfalfa, and soybeans.

I was wondering: what would be a pollutant that can be measured without advanced lab equipment and is also not harmful to myself when I handle it? Many of the pollutants in the experiments are carcinogens. I would have to be able to measure changes in the soil or water over time or at least at the end, and not be exposed to anything harmful as well.

The exact details of my project have not been decided yet; I am going to decide on one after I can decide on the pollutant, because that is a major limiting factor for my ideas. Thank you for any help you can give.

[crystalball]

Hello and welcome to Sciencebuddies!

Your project on phytoremediation sounds very interesting and useful especially in an era where there is so much pollution! You listed mostly organic compounds as the unusable pollutants---have you thought about using heavy metals which are also pollutants? These include zinc, copper, iron, selenium etc. You could add high school chemical solutions such as zinc chloride to your water or soil to test those. There is a good review article here about the activity of such metals on the environment: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2266886/

You could also use oils in your experiments to simulate oil spills or other industrial accidents that can cause irreparable damage to the environment. I know of some students who have done such experiments with normal cooking oils such as canola oil, though I am not sure how much you can extrapolate to crude oil. Perhaps experts that have expertise in this area can provide details about that.

You seem off to a great start and have clearly done much research on your topic! Let us know if you have any more questions!

-crystalball

[night70]

Thank you for the help! I wasn't thinking about about zinc and iron before, but now that you mentioned it, those would be very easy to obtain.

Another question that I have is: How would I be able to detect if the metal is still there after certain periods of time if I were to use soil? Would I have to completely separate the metal from the soil to tell the difference? (I'm just a beginning chemistry student, so I don't know if there is a certain instrument or method to do this with.)

If there is no easy way to do it with the equipment I have available, I suppose I could grow the plant hydroponically?

[caraskl]

Hi,

I do not know what types of equipment that you can access, but you can detect metals in soil using the following analytical chemistry techniques.

1. Inductively Coupled Plasma (ICP) detects and analyzes trace metals by atomizing and ionizing a sample (previously subjected to acid digestion) in argon gas. In ICP-OES, each atom emits light at wavelengths characteristic of its element of origin. Other ICPs are coupled to MS techniques, so elements are identified by their mass-charge ratio. Sensitivity of ICP can range from ppm to low ppb (Quadrupol ICP-MS), parts-per trillion to parts per quadrillion (High resolution ICP-MS), and 160-800 nm (ICP-OES).
2. Spectrophotometry measures the amount of light absorbed by analytes in a sample. The most common spectrophotometers are in the UV and visible spectrums. You can detect concentration by using Beer's Law, which holds that concentration of analyte is proportional to the amount of light absorbed.

Wish you the best on your experiment.

[night70]

Thank you for the techniques. I will ask my teacher to see if we have either of those instruments, and if not, I will check my list to see which plants can be grown hydroponically.