Glyphosate-based herbicides are herbicides made of a glyphosate salt usually combined with other ingredients needed to stabilize the formula and allow penetration into plants. Roundup was the first glyphosate-based herbicide, developed by Monsanto in the 1970s. It is used most heavily on corn, soy, and cotton crops that have been genetically modified to be resistant to the herbicide. Some products include two active ingredients, such as Enlist Duo which includes 2,4-D as well as glyphosate. As of 2010, more than 750 glyphosate products were on the market. The names of inert ingredients used in glyphosate formulations are usually not listed on the product labels.
Glyphosate and glyphosate-based herbicides have low acute toxicity in mammals. They likewise have not been shown to pose a significant risk to human health during normal use, although human deaths have been reported from deliberate ingestion of concentrated RoundUp. It is difficult to determine how much surfactants contribute to the overall toxicity of each formulation. Glyphosate formulations containing the surfactant polyethoxylated tallow amine (POEA) are sometimes used terrestrially, but are not approved for aquatic use in the US due to their toxicity to aquatic organisms.
There have been multiple lawsuits against Monsanto asserting that exposure to glyphosate herbicides is carcinogenic and that the company did not adequately disclose the risk to consumers. In 2018 a California jury awarded $289 million in damages (later cut to $78 million on appeal[1] then reduced to $21 million after another appeal[2]) to a groundskeeper who argued that Monsanto failed to adequately warn consumers of cancer risks posed by the herbicides.[3]