The premise for the study is that as natural water sources are rapidly drying up, increasingly the re-use and recycling of water means that sewerage is being used as an alternative source of water for a variety of applications, including irrigating and fertilizing farm land.
Alison Franklin, who is heading up the team of scientists, says that the big question about these compounds that remain in effluent water is: “where do they go?”
What happens the compounds?
There is a body of scientific study, including research into the environmental effects of triclosan, to determine what happens to the compounds from both personal care and pharmaceutical sources, but Franklin and her team also wants to move that research forward by determining what impact those compounds might have if they remain active.
"As I learned about pharmaceutical and personal care products in the environment, I became very interested in where these compounds were ending up,” said Franklin.
“What were the possible implications of these low level compounds in the environment on human, animal, and ecological health?"
Tracking the path of four compounds
To this end, Franklin and her team have set out to track the path of four specific compounds found in effluence that is used to spray wheat crops in a 600 acre area of farming land at the Living Site in Pennsylvania State.
The team measured the amounts of three different antibiotics and one seizure medicine in effluence before it was used to treat the wheat crops at the Living Site.
Samples of the wheat were then collected before and after harvesting and analysed for traces of four of the compounds.
Compounds remain present, study finds
"The concentrations of the compounds in the effluent were fairly low, so I was quite surprised when we were able to actually quantify the compounds in the samples," said Franklin.
The research findings, which have been published in the Journal of Environmental Quality, showed that the pre-harvest samples all had traces of the compound on the outer wheat plant, but insignificant amounts were found in the inner plant and wheat grains.
In the harvested wheat, trace amounts of all four compounds were found on the plants surface, while three of the compounds were detected in the plant parts. Two compounds were detected only in the grain and not in the straw, while the third compound was detected in both the grain and the straw. However, none of the compounds were reported to be at toxic levels.
Franklin says that the next stage of the research will be determine if any of the compound traces detected in the wheat might pose a risk to either animals or humans.