Zooplankton serves as food for baby fish and shrimp, and acts as a conduit for the movement of oil contamination and pollutants into the food chain, they said.
"Traces of oil in the zooplankton prove that they had contact with the oil and the likelihood that oil compounds may be working their way up the food chain," Michael Roman of the University of Maryland Center for Environmental Science said.
A study published in the journal Geographical Research Letters confirms that not only did oil affect the ecosystem in the gulf during BP's world record marine oil spill but was still entering the food web after the blown-out well was capped.
The fingerprint of the Deepwater Horizon oil spill could be found in some zooplankton as much as a month after the leaking wellhead was capped, the researchers said.
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