Toxicity of dispersant Corexit 9500A and crude oil to marine microzooplankton.
In 2010, nearly 7 million liters of chemical dispersants, mainly Corexit 9500A, were released in the Gulf of Mexico to treat the Deepwater Horizon oil spill. However, little is still known about the effects of Corexit 9500A and dispersed crude oil on microzooplankton despite the important roles of these planktonic organisms in marine ecosystems. We conducted laboratory experiments to determine the acute toxicity of Corexit 9500A, and physically and chemically dispersed Louisiana light sweet crude oil to marine microzooplankton (oligotrich ciliates, tintinnids and heterotrophic dinoflagellates). Our results indicate that Corexit 9500A is highly toxic to microzooplankton, particularly to small ciliates, and that the combination of dispersant with crude oil significantly increases the toxicity of crude oil to microzooplankton. The negative impact of crude oil and dispersant on microzooplankton may disrupt the transfer of energy from lower to higher trophic levels and change the structure and dynamics of marine planktonic communities.
Marine Science Institute, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373, United States. Electronic address: ralmeda2010@live.com.
Rodrigo
R
Almeda
Marine Science Institute, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373, United States.
Cammie
C
Hyatt
Marine Science Institute, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373, United States.
Edward J
EJ
Buskey
D000818:Animals; D016798:Ciliophora / Q000187:drug effects*; D004141:Dinoflagellida / Q000187:drug effects*; D004357:Drug Synergism; D008055:Lipids / Q000633:toxicity*; D008800:Mexico; D010578:Petroleum / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015048:Zooplankton / Q000187:drug effects*
D008055:Lipids; D010578:Petroleum; D014874:Water Pollutants, Chemical; C470995:corexit 9500
Corexit 9500A dispersant; Crude oil; Deepwater Horizon oil spill; Environmental pollution; Marine microzooplankton; Toxicity