The World Health Organization unit, International Agency for Research on Cancer (IARC), has classified a widely used herbicide, 2,4-D, as having properties that "possibly" cause cancer in humans.

Upon IARC's review on the scientific literature of the product, it decided to classify the herbicide as "possibly carcinogenic to humans."

The classification was made amidst the debate between environmental and consumer groups, who are fighting for U.S. regulators to restrict the use of 2,4-D, while farm groups that advocate the importance of the herbicide in food production argue that they do not need restriction.

Dow AgroSciences, a unit of Dow Chemical Co. that developed the weed killer in question, has had a particular interest in IARC's review. Dow had no comment on the IARC classification, but the company stands by its product, saying that it is safe and a valuable tool for agriculture.

Among the research presented to IARC was an analysis funded by a Dow-backed task force that found no ties between 2,4-D and many cancers, Reuters reports.

While some critics believe that IARC's classification is right, Dow's research shared that there is no reason to regulate.

"Not one health and safety regulator in the world consider 2,4-D to be a human carcinogen," the 2,4-D Research Task Force said in a statement to Reuters via Business Insider.