Environmental protection advocates called for urgent action on Thursday after a report published in Science detailed a huge rise in low-oxygen “dead zones” within the planet’s oceans.

The increased use of chemical fertilizers by the industrial agriculture sector over the past several decades , the study  warns, has prompted large-scale run-off of sewage and other byproducts entering ocean waters, causing deoxygenated dead zones to quadruple in size since 1950—now covering an area roughly the size of the European Union.

“These findings are no surprise, and further confirm that the unchecked pollution from industrial agriculture has reached crisis levels and requires immediate action,” Lucia von Reusner, campaign director for Mighty Earth, said in a statement. “Companies like Tyson Foods are driving the demand for vast quantities of unsustainably-produced corn and soy that are leaking the bulk of the nutrient pollution into our waterways, in addition to the manure that is often dumped on fields where it then washes off into surrounding waterways.”

Low-oxygen dead zones make the ocean less inhabitable for marine life, suffocating creatures and reducing the area where they’re able to thrive.

“Major extinction events in Earth’s history have been associated with warm climates and oxygen-deficient oceans,” reads the report, completed by UNESCO’s International Oceanographic Commission and the Smithsonian Environmental Research Center.

“Under the current trajectory that is where we would be headed,” Denise Breitberg, who led the study, told the Guardian.

The solution to deoxygenation lies largely in the actions of Big Agriculture going forward, environmental groups say. Local anti-pollution efforts in the Chesapeake Bay in Maryland and the Thames River in England have made a difference, allowing marine life to thrive in waters that were once maligned for their contamination levels. The study urges a global shift in farming practices.

“These dead zones will continue to expand unless the major meat companies that dominate our global agricultural system start taking responsibility for cleaning up their supply chains to keep pollution out of our waters,” said Von Reusner.