Sigma Lithium's 'Carbon Neutral' Claims Under Scrutiny Amid Brazilian Deforestation Allegations

Introduction: Carbon Neutrality Claims Questioned

Sigma Lithium, a Canadian mining company operating in Brazil, is facing significant scrutiny regarding its claims of achieving carbon neutrality for its lithium mining operations. The company, which markets its product as 'triple zero green lithium' and 'quintuple zero green lithium,' has had its environmental compensation strategy called into question following revelations about a carbon offset project it utilized.

Controversial Offset Project Linked to Illegal Activities

The core of the controversy centers on the Unitor REDD+ Project, from which Sigma Lithium purchased 59,000 carbon credits in mid-2023 to offset its emissions during its first year of production. This project, intended to reduce the carbon footprint of its mining operation to zero, has been under investigation by the Brazilian justice system for over a year. Allegations against the project include illegal deforestation, misappropriation of public lands, corruption, and other potential crimes. A journalistic investigation and the Federal Police's 'Operation Greenwashing' in June 2024 brought these issues to light, leading to the suspension of the project by its international certifier, Verra. The project remains on hold as of October 2025.

Broader Environmental and Social Concerns

Beyond the carbon offset project, Sigma Lithium's operations in Brazil's Jequitinhonha Valley have drawn broader criticism. The Federal Public Ministry (MPF) has issued warnings about the high environmental impact of lithium mining and its potential to exacerbate the vulnerability of traditional communities. The MPF identified 258 traditional communities affected by various companies and highlighted a 'clear deficiency' in Sigma's environmental licenses. In early September, the MPF recommended that the National Mining Agency (ANM) suspend and review lithium exploration and extraction authorizations in Araçuaí, where Sigma operates.

Research groups from several universities, including the Federal University of Minas Gerais (UFMG), have also recommended the immediate suspension of Sigma Lithium's activities at its Grota do Cirilo project. Their technical note cited serious human rights violations, irregularities in the environmental licensing process, and shortcomings in the company's environmental impact studies. Researchers also criticized Sigma's use of an opencast mining method, describing it as obsolete and producing 94% waste rock. Local communities in the Jequitinhonha Valley have reported that Sigma's activities have harmed water supplies and fueled community conflicts, with concerns raised about inadequate consultation processes.

Company's Response and Future Direction

In response to the growing scrutiny, Sigma Lithium stated that it has not used carbon credits since 2024, shifting its strategy to focus on reducing emissions directly from its own production. The company 'reaffirms its commitment to mining with a very low environmental impact, based on technological innovation, health, safety and socio-environmental responsibility.' Sigma has also defended its operations against the MPF's requests for suspension, asserting that no indigenous peoples reside within the project's legal radius, a claim it states has been confirmed by environmental agencies during the licensing process. The company has rejected allegations of insufficient consultation or flaws in its environmental studies as 'incorrect and unfounded.' Despite these challenges, Sigma Lithium secured a BRL 487 million loan from the National Brazilian Bank for Economic and Social Development (BNDES) in August 2024 to fund a second 'Greentech Carbon Neutral Plant' in Brazil.