Toxic Tons: The Largest Flow Of Illegal Mercury To The Amazon Ever Exposed

Washington, D.C. - The Environmental Investigation Agency (EIA US)’s new report, Traffickers Leave No Stone Unturned, exposes the large scale trafficking of mercury from mercury mines in Mexico - located in a United Nations Educational, Scientific and Cultural Organization (UNESCO) Biosphere reserve, to gold mines in Bolivia, Colombia, and Peru in violation of the Minamata Convention on Mercury. According to EIA’s findings, from April 2019 to June 2025, approximately 200 tons of mercury have been trafficked–resulting, by conservative estimates, to the production of at least US$8 billion worth of illegal gold, at current prices. The investigation shows how mercury and gold trafficking intersects with organized crime in both Mexico and Colombia. Acting on EIA’s intelligence, Peruvian customs authorities stopped approximately 4 tons of Mexican mercury in June 2025, the largest seizure ever reported by an Amazonian country. This groundbreaking case sheds new light on the enforcement gaps and loopholes of the Minamata Convention on Mercury, raising urgent questions about its effectiveness to face the often highly covert and organized criminal groups that control mercury and gold trafficking.

Due to a combination of economic, geopolitical, and market factors, the price of gold has risen sharply since 2023, reaching a historic high in April 2025 with a price of US$3,500 per ounce. This was largely attributed to trade tensions between the United States (U.S.) and China, which led investors to look for safe investments opportunities, like gold.

A significant portion of the gold being produced globally each year comes from illegal sources. Estimates for illegally extracted gold in Amazonian countries run from roughly 28% to nearly 90% of total production, depending on the country, while illegal gold mines have spread in recent years, becoming a significant regional driver of deforestation. Recent studies show that the cumulative deforestation footprint from gold mining across the Amazon reached over 2 million hectares (nearly 5 million acres) by 2024, having increased by over 50% in the past six years. A third of the impact is located in protected areas and Indigenous territories, including on Yanomami, Munduruku, and Kayapó territories.

The current onslaught of illegal gold mining in the Amazon wouldn’t be possible without mercury. Miners use mercury to form an amalgam with gold-bearing sediments. The amalgam is then heated, vaporizing the mercury and leaving behind gold. This process, while rudimentary, is central to illegal mining operations across the region and is the main driver of mercury pollution in the Amazon.

This process also releases large amounts of mercury into the environment. Gold mining is now the world’s largest source of airborne mercury pollution, releasing over 800 tons annually into the atmosphere. The mercury used in these operations contaminates soil, waterways, and forests. Mercury, which is a highly dangerous neurotoxin, enters the food chain, bioaccumulates, and causes severe neurological disorders and multiple other serious health problems for Amazonian communities.

Alexander von Bismarck, Executive Director at EIA US, explains: “The toxic flow of mercury to the illegal gold mines in the Amazon has been presented and accepted as inevitable for too many years, it is time to challenge this status quo that affects Amazonian communities and benefits organized criminals.”

From April 2019 and June 2025, EIA has investigated and documented the smuggling of approximately 200 tons of illegal mercury, which represents the largest flow of illegal mercury ever reported globally. The mercury route starts in the state of Queretaro in Mexico where a few active mercury mines are producing dozens of tons of mercury each year in order to feed gold mining demand in the Amazon. Several of these mines are located within the Sierra Gorda UNESCO Biosphere Reserve. Evidence collected by EIA indicates that some of the mines are controlled by the Jalisco New Generation Cartel. As of May 2025, sources from the Queretaro mines told investigators that a new “mercury fever” has hit the region since 2025, triggered by record high prices (US$330 per kilogram of mercury) offered by mercury traffickers, as a consequence of skyrocketing gold prices.

According to EIA’s investigation, Mexican mercury flows to often cartel-controlled gold mines in Bolivia, Colombia, and Peru, with some transhipment via the U.S. For instance, drug cartels in Colombia control an important part of domestic mercury trafficking routes. According to conservative estimates, the smuggled Mexican mercury has been used for the extraction of, at the very minimum, US$8 billion worth of illegal gold (at the current price of US$3,300 per ounce).

Based on EIA’s intelligence, Peruvian customs authority (Superintendencia Nacional de Aduanas y de Administración Tributaria - SUNAT) disrupted the Peruvian branch of a transnational organized criminal network via the seizure of a shipment of approximately 4 tons of smuggled mercury transhipped in Peru and inbound to Bolivia. The shipment was transported by Ocean Network Express (ONE) on a Hapag Lloyd vessel. This mercury seizure represents the largest ever reported by an Amazonian country.

Alexander von Bismarck comments: “As long as mercury mines remain open, in Mexico or elsewhere, smugglers will find their ways around. The problem must be addressed at its roots.”

While the Peruvian success against organized smuggling is a major step forward in the effort to combat illegal gold and mercury in the Amazon, EIA’s findings raise serious questions regarding the effectiveness of the Minamata Convention on Mercury and in particular its implementation in Mexico. Several critical issues must be urgently addressed – particularly at the upcoming 6th Conference of the Parties of the Convention in November 2025 – including: the grace period that allows mercury mines to remain open and continue to produce primary mercury fueling illegal gold mines around the world; the lack of effective enforcement that allows mercury mines to remain active albeit formally illegal or unauthorized; the fact that ASGM is considered an “allowable” use of mercury under the Minamata Convention – a loophole that every day hurts ecosystems and hundreds of families across the Amazon.

© Scoop Media