Smuggled mercury shows extent of illegal Amazon gold mining

Japan Times

28-07-2025

The seizure of one of the largest known mercury shipments in history, moving from mines in Mexico to illegal Amazon gold mining zones, exposes the wide use of the toxic metal in the rain forest, according to authorities.
Peru's customs agency, SUNAT, found 4 metric tons of illegal mercury in Lima's port district of Callao, according to a report by the nonprofit Environmental Investigations Agency (EIA).
"This SUNAT intervention has prevented this chemical from having a serious impact on people's health and the environment, as can be seen in several areas of the country devastated by the illegal use of mercury and illicit activities," SUNAT said in a statement.
The vast transnational smuggling operation trafficked some 200 tons of elemental mercury over more than six years, an amount that would have contributed to the production of at least $8 billion worth of illegal gold, according to the EIA, which worked alongside SUNAT to uncover the network.
"The toxic flow of mercury to the illegal gold mines in the Amazon has been presented and accepted as inevitable for too many years," said Alexander von Bismarck, Executive Director at EIA U.S.
Brazilian Environmental Agency (IBAMA) agents participate in a Brazilian government enforcement operation to combat illegal gold mining in the Amazon rainforest on Munduruku Indigenous land, in the municipality of Jacareacanga, Para state, Brazil, on Nov. 12, 2024. |
REUTERS
"It is time to challenge this status quo that affects Amazonian communities and benefits organized criminals," he said.
The scheme spanned at least four countries — Mexico, the country of origin, Peru, the destination for three-quarters of the mercury, Colombia and Bolivia — between April 2019 and June 2025.
All four are signatories of the Minamata Convention on Mercury to protect human health by reducing and ultimately eliminating mercury use, and the undeclared shipments were in direct violation of the convention.
Record gold prices have encouraged a flourishing illegal mining trade that damages local nature and biodiversity and is raising significant health concerns.
With the price of gold surpassing $3,000 per ounce, mercury, which is used to extract the gold in illegal mines in the Amazon, is worth four times as much.
A highly dangerous neurotoxin, mercury is one of the top 10 chemicals of major public health concern, according to the World Health Organization (WHO).
It enters the food chain, bioaccumulates and causes developmental delays in children, cognitive impairment and multiple other serious health problems for Amazonian communities.
"To extract gold, rivers and streams are polluted, and territories are plundered," said Julio Cusurichi, an Indigenous leader and Goldman Environmental Prize winner, in Madre de Dios, the Peruvian Amazon region most heavily impacted by illegal gold mining.
"Mercury pollution even affects fish, which is the daily diet of our Indigenous communities. Now the contamination is reaching all of us who live in the Madre de Dios region, Indigenous or not," he said.
Mercury air pollution in parts of Madre de Dios is more than 5.5 times higher than the WHO's safety levels.
The investigation uncovered a network involving organized crime groups allegedly centered around a mercury trader identified as Juan José Zamorano Davila, based in Querétaro state, Mexico, according to the EIA and Peruvian authorities.
Zamorano allegedly oversaw procurement, concealment, export logistics and financial structuring of the shipments, according to the EIA.
A law enforcement agent holds a bottle of mercury used in gold panning during an operation against illegal gold mining at the Urupadi National Forest Park in the Amazon rainforest, in the municipality of Maues, Amazonas state, Brazil, in 2023. |
REUTERS
The route begins in Querétaro, where a few active mercury mines, some located within the Sierra Gorda UNESCO Biosphere Reserve that is considered a unique ecosystem of cultural significance, produce dozens of tonnes of mercury each year to feed gold mining demand in the Amazon.
Evidence collected by EIA indicated some of the mines are controlled by the Jalisco New Generation Cartel, one of Mexico most powerful illegal drug networks.
In May, sources from the Querétaro mines told investigators that "mercury fever" has hit the region this year, triggered by record prices of about $330 per kilogram offered by mercury traffickers as a consequence of skyrocketing gold prices.
Once smuggled into South America from the Mexican port of Manzanillo, the mercury was moved through ports and companies with alleged ties to organized crime and resold in illegal gold mining zones, including territories controlled by armed criminal groups like the Clan de Golfo (AGC) and the ELN in Colombia.
The mercury found in the port of Callao was hidden in sacks of gravel and falsely declared as crushed stone or decorative rocks to bypass customs.
Invoices for the shipments were inflated and misclassified to disguise their contents. Each 20-ton container was declared at $11,000 (about 20 times higher than legitimate gravel prices) despite actually containing mercury worth up to $2 million.
The container intercepted in Peru tested positive for mercury vapor levels 480 times above safety thresholds.
The shipment was marked as destined for Bolivia, passed through the port of Callao and, the investigation showed, was diverted through Peru's southern city of Arequipa, a distribution hub for destinations such as Madre de Dios.
Similar shipments were traced to Colombia as well as Bolivia, often routed through the U.S. port of Houston, creating a potential jurisdiction issue in the United States.
The routes underscore the global nature of the trafficking operation and also bring attention to limited inspection in transshipment scenarios, the report said.