The US Environmental Protection Agency (EPA) has recently moved to reapprove the application of the herbicide dicamba on genetically engineered soybeans and cotton. This decision is primarily driven by the urgent need to address resistant weed outbreaks, which adversely affect crop productivity. The reapproval pertains exclusively to “over-the-top” (OTT) treatments, where dicamba is applied over growing crops to manage emerging weeds.
While beneficial, dicamba has a controversial background due to its tendency to drift away from targeted zones, impacting non-resistant crops and various plant species. This drift issue has resulted in significant legal disputes, including a notable settlement from Bayer, where the company consented to pay $400 million to settle lawsuits linked to damages caused by dicamba drift.
The EPA emphasizes that its recent ruling includes strict label restrictions aimed at alleviating previous concerns. These updated regulations involve reducing the maximum annual dicamba usage by half and implementing application restrictions during high-temperature periods that increase drift and volatilization risks. The agency’s reapproval claims no unreasonable risks to human health or the environment with these new standards in place.
This action by the EPA follows a 2024 US court ruling that overturned its prior 2020 dicamba approval due to procedural errors. The recent decision has faced criticism from environmental organizations, which point to possible regulatory bias following the recent appointment of a former lobbyist from the agricultural sector to a senior role within the EPA.
Globally, the usage of dicamba is inconsistent, with its approval in the EU restricted until March 2027 and strict regulations enforced. The EU’s refusal to authorize dicamba-tolerant crops avoids the OTT application issues that are prevalent in the US. Similar regulatory frameworks are present in countries such as Australia, where protective measures are in place to prevent dicamba drift onto vulnerable crops.