Testing for DDT and pDDT

[vaishmanu]

I am testing the effects on DDT in the calcite of marine organisms. However, I have come across the problem of how to test my water for the concentration levels of DDT and pDDT. DDT is now illegal in the U.S.A. so I am using already contaminated waters off the south bay in California. More specifically I am using water off the Cabrillo Marine Aquarium beach. It appears I cannot buy a test kit. So I need to know in order to have my water tested do I have to get it commercially tested? Also is there any specific instrumentation I will need? Thank you.

[MelissaB]

In order to measure DDT levels in water, you will need to be able to do gas chromatography and mass spectrometry, which requires very expensive and delicate equipment. If you can find a commercial test, you can certainly use that, but I would suggest contacting your local university and asking if there is anyone who studies pollutants in water. They may be willing to mentor you and help you perform the necessary tests. If you find a commercial test, you shouldn't need any additional instrumentation--you should be able to just send them water samples (talk to the company to find out exactly how they want you to collect the samples).

If you know the water is already contaminated, you could potentially just do a test with contaminated vs. uncontaminated water and reference the work of the person or group who found DDT in the water; if they found DDT, they probably also measured the amount. Would it be possible to contact this person/group?

This is a really interesting topic--good luck!