Oil spills are harmful for marine life. We've seen some pretty bad oil spills in the past few years, most notably the Deepwater Horizons BP oil spill from 2010, the biggest oil spill in history. Researchers are still finding ways in which the BP oil spill harmed animals, like causing deadly lesions in fish.

So why would anyone want to intentionally dump oil into the sea? To study how it works better, so that scientists can come up with a way to contain the next disaster when it happens.

When petroleum enters a body of water, some of it immediately dissolves into the sea, releasing toxins called hydrotoxins that are deadly to marine life and humans alike. A new study published in the journal Environmental Science & Technology intentionally released oil into the North Sea so that they could study the flow of hydrocarbons over the first day after a spill.

During a spill, the ocean may be the first time the oil has seen light or air for millions of years after being trapped underground or held in tanks. "In its new environment, the oil immediately begins to change its composition, and much of that change happens on the first day," says Samuel Arey, who works at Ecole polytechnique fédérale de Lausanne (EPFL) and Eawag in Switzerland and was a lead author of the study. Volatile chemicals from the oil dissolve into the water, while others evaporate into the air, threatening all surrounding animals.

Researchers have long tried to study the route hydrocarbons take after an oil spill. However, it was difficult to study because by the time researchers arrive on the scene after a spill, much of the chemicals have already spread. This study sought to get the full picture by intentionally releasing oil into the sea and tracking the hydrocarbons for 24 hours.

The team created a four cubic meter (141.26 cubic feet) spill in the Europe's North Sea. They were able to glean a lot of useful information from the spill about the way that toxins spread immediately after. The scientists are planning to use a computer model based on their findings to study oil spills further in the lab. They hope to use their findings to plan better ways to respond to oil spills and help figure out how spills will affect human workers, even in conditions that are completely different from the ones they created in the North Sea. The spread of oil spills depends very much on environmental factors, such as winds and temperature.