Science Buddies: "Ask an Expert"

Hi,
I am doing a science fair, Does the temperature of the ocean water affect how much Bisphenol A is found in the ocean water? I have a done a lot of research but was unable to figure out how to measure the Bisphenol A in the ocean water. Do I need to use a chemical or machine? Anything can help, thank you.

Hello Nicole21,
Thanks for your question and welcome to Science Buddies!
Your question of how to measure the amount of BPA in ocean water is a good and relevant one in health and environmental issues we currently face. Using Mass spectrometry, liquid chromatography is the most common way to measure particles in substance, but they are both expensive equipment. Do you have a lab you can use? Sometimes your school or a local college has one you can use. Maybe you can ask your science teacher? But, I found a kit online that is pretty inexpensive ($30): http://www.home-health-chemistry.com/BPA-Test.html. There are instructions on how to perform the testing in water. Remember that this is a consumer kit, not a science kit, so you will want to include that in your report. I'm not sure how that would translate to ocean water, since the ocean contains more particles, and salts than water. You will need a control (a sample that does not contain any of the experimental substance), for instance if you are trying to test whether a plastic bottle leaches more BPA in warmer salt-water, your control will need to be putting the bottle in room temperature salt-water. You want to keep your variable constant (which is temperature). Choose your variable: sounds like you want to test the effect of different temperatures? Here is some information on controls and variables: https://www.sciencebuddies.org/science- ... bles.shtml, and: https://www.sciencebuddies.org/science- ... ndex.shtml

You are trying to test to see if the hotter temperatures of ocean water will lead to more leakage of BPA? What is your hypothesis, based on your research.

Here are a couple of articles I found that could be of assistance:
http://news.nationalgeographic.com/news ... -seas.html
http://www.bisphenol-a.org/about/faq.ht ... Qgod9kQAng
http://en.wikipedia.org/wiki/Bisphenol_a

Hope that helps you get started. Please post again here for your other questions. I look forward to hearing how your project is going.

Thank you so much for the kit, the only problem is I am not going to be testing a object, I am going to be testing the water itself. Instead of boiling water, can I just put the swab into the different temperature of water? Also, this doesn't seem to produce numbers I can graph for data, is there a way I can convert the data into numbers?

Hi Nicole,

I don't see why you can't do as you described and just use your sample water in place of the boiled water the kit asks for. Just make sure you are very controlled about the container you are using, since certain types of containers have BPA in them (i.e. some plastic bottles, etc). As for quantitation, you are correct that this kit does not give you a way to truly quantify your data so that you can graph it. I would probably describe it as semi-quantitative, since it does turn three different colors depending on the concentration of BPA in your sample. You could use these ranges as data points to graph your samples, but there may not be enough difference between samples for them to fall into different colors, depending on how broad the ranges are.

There are other kits available that are more quantitative, but they are designed for science labs and are quite expensive (~$600), so I'm not sure it's worth the extra money for you, not to mention that it would require some more sophisticated equipment. I'll post links to them below though, in case you are interested.
http://www.mybiosource.com/datasheet.ph ... _id=703174
http://www.clontech.com/takara/US/Produ ... isphenol_A

I'm sorry I am a little confused, the procedures on the kit says to take the object I am testing and to put it in some boiled water. If I put the ocean water in boiled water, it will change the temperature of the water and affect my experiment.

I'm sorry I didn't read the procedure carefully enough and I wasn't very clear in my last answer. Yes, I think you can simply dip your swab into your sample ocean water at your temperature. Again though, make sure your ocean water is always in the same container to control for BPA leeching out from the container.

Thank you so much for your help, I am really excited to see how my project will turn out!