Remember the 2010 Deepwater Horizon incident? It doesn’t take much brain power to imagine the amount of damage done to marine wildlife in the Gulf of Mexico. The disaster saw upwards of four million barrels of crude oil released into the water. The scientific community already knew that the crude oil in the spill affected many marine species; that in many species of developing fish, crude oil may be a Cardiotoxin . It also knew that the presence of crude oil in marine habits was disruptive and detrimental for many species. But although they had known the “what” in the equation, they were still lost on the “how”.
But now the “why” is looming on the not-yet distant horizon of the disaster. A team of Stanford has discovered the physiological effects that huge quantities of crude oil can have on wildlife. SciTechDaily reports on the team’s findings, which illuminate the previously murky unknown. By studying tuna, the Stanford team discovered that small amounts of crude oil prove detrimental to health marine fauna. To be exact, crude oil slows the heartbeat of these organisms.
How exactly, does this happen? This report in SciTechDaily explains it well. To understand how crude oil complicates normal heart functions, we must first understand something called “polycyclic aromatic hydrocarbons”, or PAHs. Sometimes toxic, PAHs are found in crude oil, and can linger in marine environments well after the initial spill happens. Sometimes, these PAHs stick around for a few years.
The oil disturbs essential processes and functions that prove necessary for a healthy, beating heart. Crude oil slows down the heartbeat by disrupting the potassium ion channels that restart the heart. The heart depends on the fluid movement of several ions, so when these channels are not functioning properly, they hinder a regular heartbeat.
But the discovery that PAHs cause heart complications is not just limited to the marine biosphere. See, the protein channels the scientists observed in tuna hearts are similar to other vertebrate hearts, including humans. Also, PAHs are not limited to crude oil, but have also been found in coal tar, runoff, and air pollution. This means that humans inhabiting areas with heavy levels of air pollution could be at risk for arrhythmias and reduced heart speed.
The study itself is part of an ongoing effort to examine the environmental impact of the spill from nearly four years ago, and there is still more to discover moving forward.