The main concern with it is that it spreads to and damages nearby non-target plants. Several such cases have been reported and the US Environmental Protection Agency (EPA) is following up on them.
In August 2022, new risks of the herbicide dicamba were identified by the EPA. According to the environmental risk assessment aimed only at wildlife populations that are not federally listed as endangered, the agent may pose a potential chronic risk to bees at higher exposures than previously examined. In addition, there is also a risk to fish in limited circumstances (application on sugar cane in Florida). Previously raised concerns for birds have been alleviated, while no risk has been identified for aquatic invertebrates.
The previous human health risk assessment was also reviewed, but it agrees with the previous findings.
The EPA has approved the continued use of dicamba. According to the Center for Biological Safety (CBS), the new findings underscore the need for further restrictions on dicamba.
Dicamba has received criticism for years. In summer 2020, the court banned the use of the dicamba agents. Then the EPA gave deadlines for its use and granted another 5-year license with new restrictions, which prevent the unwanted spread of the agent - there should be a certain distance from non-target plants and it should be mixed with a buffer that inhibits its spread.
According to an article published in October 2022, to prevent the drift of pesticides (e.g. dicamba drift), certain amines are mixed with the agents, but these inhibitors themselves are volatilized as well. The source of amines in the atmosphere is constantly being researched, as they can form carcinogenic substances, but their mixture with herbicides has not been studied so far.
According to information from April 2023, a new lawsuit was filed against the EPA as a continuation of the previous one, because after the 2020 court order, in which the use of dicamba was prohibited, it reauthorised it with certain modifications, while in a 2021 analysis the agency found that problems with dicamba persisted.