Effects of oily marine aerosol in cardiovascular flow of embryonic Gulf Killifish

Exposure to spilled crude oil in water and sediments has been shown to negatively affect cardiovascular development in various embryonic organisms, but the effect of airborne oil exposure is not well known. Here we examine the effects of oily marine aerosol exposure on the cardiovascular fluid dynamics of embryonic Gulf Killifish (Fundulus grandis), which develop outside the water. We acquired high speed footage of in vivo blood flow at 40× magnification in the 17.5 µm diameter sinoatrial nodal artery in control and oil-exposed embryos at 10 and 11 days post fertilization. Image processing was used to register and mask images, subtract the average background, and normalize intensity, and particle image velocimetry was performed using erythrocytes as tracer particles. The mean Reynolds and Womersley numbers in the control group were 0.0024 and 0.0123, respectively. Oil-exposed groups had reduced cardiac output, mean blood flow velocity, hatching success, and body length and increased heart beat rate and hematocrit level as compared to the control group. Similarly, shear stress on the vessel walls is estimated to be lower for the oil-exposed group. These results suggest defects during cardiogenesis and degradation of cardiovascular performance due to oily marine aerosol exposure.