Syngenta, a Swiss chemicals company, produces one of America's most popular herbicides. It is called atrazine, and 73.7 million pounds of the chemical compound were applied in the United States in 2013. It was used on more than half of all corn crops, two-thirds of sorghum and up to 90 percent of sugar cane. The weed killer is banned as a pesticide in the European Union as well as in Switzerland over concerns that it is a groundwater contaminant. Syngenta, however, did not get the memo. Even though the European Union banned atrazine over a decade ago, the company has long insisted that the pesticide was not banned. Sensitivity over regulatory gaps between the United States and Europe has flared during trans-Atlantic trade talks, which have been underway since 2013. An increasing number of critics of the process are concerned that the outcome could favor corporations more than consumers. Advocacy groups have particularly focused on chemicals, given the disparities in policy. Baskut O. Tuncak, a senior lawyer at the Center for International Environmental Law, said that in his view the chemical proposals that have surfaced so far "reflect a lot of industry's demands and their concerns with more protective E.U. policies." He added that proposed changes could "slow or stop and possibly weaken efforts to develop stronger chemical regulation in either the E.U. or the U.S."