Scientist use ingredient found in shampoo to monitor oxygen in the oceans
Scientists at the University of Leicester are using an ingredient found in
common shampoos to investigate how the oxygen content of the oceans has changed
over geologically recent time.
The same ingredient, which was also used to fight off alien invaders in the
film “Evolution”, is a widely available dietary supplement used by many people.
The ingredient, selenium, is an anti-oxidant and an essential trace nutrient
in our diet. It belongs to a group of elements whose behaviour is controlled by
the concentration of oxygen in the environment.
This study represents a first attempt by scientists to use selenium in this
way and is part of research student, Andrew Shore’s, PhD project. It involves
measuring the isotopic ratios of selenium in sediments.
One possible outcome of the project is that the results could give scientists
a global picture of the changing oxygen content of the oceans through time.
Previous studies have tended to focus on local variations in ocean oxygen
content.
The oxygen content of oceans can also be used as an indicator of the “overall
health” of the oceans. The recent report from the Intergovernmental Panel on
Climate Change (IPCC) states changes in fish populations are “associated with
changes in oceanic oxygen levels.” Therefore an understanding of oxygen in the
oceans is not only important for the past but also for the future.
“We are using samples from an ocean basin off the Venezuelan coast which
previous studies have shown to have changed its oxygen content over the last
500,000 years,” explained Andrew.
Without oxygen living things suffocate. Six hundred million years ago, the
only life that could survive was tiny single-celled organisms. Then suddenly 540
million years ago complex life began to thrive, possibly as the “miracle
molecule”, oxygen, became abundant on Earth.
Andrew added: “Our understanding of the changes in atmospheric oxygen is
good, but our planet is 70% covered by oceans. Determining the oceanic oxygen
content is very difficult - it is linked to the atmosphere, plankton growth, and
ocean circulation patterns.”
This research is funded by the Petroleum Research Fund of the American
Chemical Society and is in collaboration with Dr Gawen Jenkin, University of
Leicester, and Dr Tom Johnson, University of Illinois at Urbana-Champaign.
Andrew did his first degree at the University of East Anglia, studying
Environmental Sciences. While there, he became interested in oceanography,
geochemistry and quaternary sciences. It was during a year abroad, studying at
the University of Illinois, he first became involved with this research. - U.
Leicester
More information:
Elizabeth Newall
University of Leicester
Email en26@le.ac.uk
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