Veggies are supposed to be healthy. A new article in the New England Journal of Medicine is arguing that the US needs to do further testing of one of the world’s most popular pesticides to ensure it is in fact safe.

As the Independent News reports, two esteemed health experts have written an opinion piece claiming previous research was inadequate. Dr. Philip Landrigan and Chuck Benbrook state that the most commonly used herbicide, glyphosate, is not as safe as previous enquiries have indicated.

“There is growing evidence that glyphosate is geo-toxic and has adverse effects on cells in a number of different ways,” they write. “We believe the time has therefore come to thoroughly reconsider all aspects of the safety of plant biotechnology.”

Glyphosate is the main ingredient in popular pesticide Roundup, developed by agriculture giant Montsanto. It is also used in over 700 other products and has been found in traces in both food and water.

The article argues studies that said glyphosate was safe were faulty and/or commissioned by the manufacturers. However, in March the World Health Organization classified it as “probably carcinogenic.” The authors also point out their concern that too little of the research had focused on the effects on children.

Montsanto has stated they will be performing their own research. For now, the products will all remain on the shelf.