Update: March 2, 2026 – 10:00 a.m.

Read in spanish

On June 1, 2025, around 11 at night, a container arrived at the Peruvian port of Callao. It had departed five days earlier from the port of Manzanillo in the Mexican state of Colima. Shipping documents indicated it was carrying 800 bags of crushed stone weighing 25 kilograms each, with Bolivia as its final destination. The cargo, however, never left Peru.

Following an intelligence alert, the National Superintendency of Customs and Tax Administration (Sunat) intercepted the shipment. Laboratory analysis determined that the stone was impregnated with mercury, a key input for illegal gold mining whose import requires special permits. The amount of metal was estimated at four tons, valued at more than S/ 1.7 million (around USD 447.000), according to customs authorities.

OjoPúblico traced the smuggling route using public prosecutor sources, commercial records, and official documents obtained through access-to-information requests. The investigation, conducted in partnership with El Universal of Mexico, shows how transnational crime sources inputs for illegal economies and, allegedly, collaborates with local businesses, including a Peruvian metals trader authorized to trade gold.

According to public prosecutor documents obtained by this outlet, on June 26, 2025, the case of the seized container was transferred from the Callao Provincial Environmental Prosecutor’s Office to the National Prosecutor’s Office, as it “involves multiple countries” and concerns “alleged mercury trafficking linked to commercial operations between Mexico, Peru, and Bolivia.”

The seizure was also cited in a report last year by the NGO Environmental Investigation Agency (EIA). Between April 2019 and June 2025, the organization detected 50 concealed mercury shipments from Mexico, 37 of which were destined for Peru, consolidating the country as the main market for this illicit trade linked to illegal gold mining.

Behind the extraction of this metal in Mexico, according to the EIA report, is the Cártel Jalisco Nueva Generación (CJNG), which controls mercury production in several mines in the state of Querétaro. OjoPúblico’s analysis, based on public prosecutor documentation, reconstructs the smuggling network transporting mercury to Peru. 

The Peruvian partner

In Lima, the investigations by the public prosecutor’s office are still at an early stage. The Prosecutor’s Office has focused on the Mexican company Exportadora de Rocas y Derivados Zace S.A. de C.V., based in Querétaro, and its legal representative Eduardo García Patlán, as well as Luz Zelmira Morena Valdivia, a natural person residing in La Paz, Bolivia, listed in the shipping documents as the recipient of the container.

According to public prosecutor documents, the investigation also targets Peruvian citizen Christan Estunder Castillo Meléndez, manager of the Lima-based company C&K Pukaray E.I.R.L., although the company does not appear in the manifest of the seized container.

Public prosecutor sources told OjoPúblico that the investigation into the company began based on a report of the Peruvian Customs Agency, which lists the company as a suspected recipient of illegal mercury shipments from Mexico. According to the authority, C&K Pukaray E.I.R.L. is engaged in the trade of construction materials.

Between 2019 and December 2025, the company imported at least 26 shipments of crushed and decorative stones, according to customs data analyzed by this outlet. All shipments came from the Mexican port of Manzanillo and were consigned by Exportadora de Rocas y Derivados Zace S.A. de C.V., the supplier of the container seized in June.

ABANDONED. The office of the Peruvian company under investigation, located in a shopping center in Lima with many empty offices, was closed during its regular business hours.

Photo: Aaron Wörz

The Peruvian public prosecutor attributes to the legal representatives of C&K Pukaray E.I.R.L. and Exportadora de Rocas y Derivados Zace S.A. de C.V., as well as to the Bolivian recipient, the “alleged commission of environmental crimes in the form of illicit trafficking of chemical inputs and machinery intended for illegal mining.”

The importing company, C&K Pukaray E.I.R.L., does not have a license to acquire or use mercury. It is also not registered in the mercury users registry of the Peruvian customs agency. In contrast, Christian Estunder Castillo has been listed since 2014 in a special registry for gold traders and processors in Peru.

The accused is not the only family member linked to alleged mercury trafficking. In 2015, his brother, Frank Harold Castillo Melendez, was stopped with 36 glass jars holding mercury on a bus traveling from Lima to Arequipa, RPP reported at the time.

The Mexican exporter

The founder and now-investigated representative of the Mexican company that shipped the container from Mexico to Peru, Eduardo García Patlan, is no stranger to Peruvian authorities. On June 24, 2024, upon entering the country, he was stopped carrying USD 40.000 in undeclared cash. For this, Sunat imposed a fine of nearly S/ 46.000 (USD 12.100).

According to Mexican commercial registry documents obtained by OjoPúblico and El Universal, in January 2020 García Patlan and his co-founder transferred all their shares in Exportadora de Rocas y Derivados Zace S.A. de C.V. to brothers Juan José Zamorano Dávila and Joel Zamorano Dávila. Joel was also fined nearly S/ 46.000 after attempting to enter Peru the same day as García Patlan, also carrying USD 40.000 in undeclared cash.

Two representatives of the Mexican company attempted to enter Peru carrying USD 80.000 in undeclared cash.

The Zamorano Dávila brothers are listed as shareholders in two other mining companies operating in Querétaro. In one of them, Juan José Zamorano serves as chairman of the board. The partners of this company hold five active mining concessions in the area, including the La Peña lot in the municipality of Tolimán, which appears in the EIA report as a potential cinnabar mine, a mineral that contains mercury.

According to Julia Urrunaga, EIA’s director for Peru, no direct link between the Zamorano Dávila brothers and the CJNG could be confirmed. However, she told this outlet that the NGO documented “on-site observations –including fortifications and access control– and reports from local testimonies pointing to a presumed cartel takeover of mines in Querétaro.”

Juan José Zamorano Dávila, who owns 95% of the shares in Exportadora de Rocas y Derivados Zace S.A. de C.V., appears on a list from Mexico’s tax administration service identifying taxpayers with outstanding tax debts. At the same time, since November 2024, he has been pursuing an administrative case against a regional tax office in Querétaro to challenge a decision against him.

OjoPúblico’s analysis determined that, in addition to the 26 alleged shipments of decorative stones to C&K Pukaray E.I.R.L. in Peru, Exportadora de Rocas y Derivados Zace S.A. de C.V. carried out five other similar shipments between 2019 and December 2025, destined for Barranquilla, Colombia.

Before the seizure in Lima, in January 2025, the Mexican company sent another shipment with the same description to the now-investigated recipient in Bolivia. Another shipment, sent in July 2021 to Bolivia, was also addressed to an individual rather than a company.

A series of OjoPúblico investigations have documented that the overland route from Bolivia to Peru has been used for years to smuggle mercury destined for illegal gold mining in the Amazon.

This outlet sent a questionnaire by email to Juan José Zamorano Dávila requesting his response to the prosecutorial investigation. As of the publication of this report, no reply had been received. It also contacted the corporate building where the office of Exportadora de Rocas y Derivados Zace S.A. de C.V. is registered in Mexico in an attempt to reach its representatives, but received no response.

OjoPúblico also visited the office of C&K Pukaray E.I.R.L. in Lima to request comment. However, the premise was closed, despite the visit taking place during the business hours posted on the notice. Calls and messages to the phone number listed on the door also went unanswered.

This outlet likewise sought to contact Luz Zelmira Morena Valdivia and Eduardo García Patlán through messages sent to their Facebook profiles to obtain their version of the story, but as of publication no response had been received.

A business off the radar

After the death of its leader, Nemesio Rubén Oseguera Cervantes, alias El Mencho, on February 22 during a police operation, the Cártel de Jalisco Nueva Generación (CJNG) unleashed a wave of violence across multiple Mexican cities, burning vehicles and blocking roads in 20 of the country’s 31 states.

Raúl Benítez Manaut, a security expert and researcher at the National Autonomous University of Mexico (UNAM), told OjoPúblico that mercury trafficking represents a business line for the CJNG, operating largely off the radar of both authorities and public scrutiny in Mexico.

Mercury trafficking in Mexico is highly localized,” said Raúl Benítez Manaut, researcher at UNAM.

“Mercury trafficking is highly localized. By contrast, other minerals, such as gold and silver, in northern Mexico are extracted by large mining companies, mostly Canadian. There is no widespread illegal mining in Mexico,” he said, adding that mercury is therefore primarily exported to countries like Peru, Colombia, and Bolivia.

The state of Querétaro, home to Mexico’s largest mercury deposits, is, according to Benítez Manaut, a “highly developed, heavily industrialized region, and there is no evidence that criminal groups have significant activity there.”

 

UNDERGROUND. The Mexican state of Querétaro is home to deposits of cinnabar, a mineral that contains mercury.

Photo: Environmental Investigation Agency (EIA)

 

The situation is different at the port of Manzanillo, from where the container seized in Callao was shipped, along with nearly all other shipments linked to the two companies under investigation. According to the expert, the port falls within the area of influence of the Sinaloa and Jalisco Nueva Generación cartels.

Benítez Manaut explained that the port also receives precursor materials intended for fentanyl production for the U.S. market, one of the CJNG’s main illicit businesses.

When asked about potential administrative investigations following the seizure in Peru, the Querétaro state’s communications office responded that mining activities fall under federal jurisdiction and that it has no record of requests related to the case. Requests for information were also sent to Mexico’s attorney general’s office regarding any ongoing investigation or coordination with Peru, but no response had been received by the time of publication.

 

Invisible smuggling method

In the case of the seized container, the technical sophistication of the smuggling method stands out. According to the Peruvian customs agency, to extract the toxic metal, the stones included in the shipment are subjected to high temperatures in furnaces through a process known as roasting, which separates the mercury in liquid form from the rest of the material. The metal is then collected in iron jars and prepared for sale within illegal mining networks.

This process takes place against a backdrop of steadily declining official mercury imports into Peru, as OjoPúblico reported in a previous edition.

Since the entry into force of the Minamata Convention in 2017 —a global treaty designed to reduce mercury use due to its serious health and environmental impacts— legal imports have plummeted from over 100.000 kilograms in 2011 to just 6.770 kilograms in 2025, creating space for illegal networks to exploit the scarcity.

 

PROTECTION. Workers of the Peruvian customs agency collect samples from the container seized at the port of Callao, whose toxic contents were destined for illegal mining in the Amazon.

Photo: Sunat

 

Luis Fernández, profesor at Wake Forest University (United States) and a mercury contamination specialist, was commissioned by the Peruvian customs agency to verify the presence of the metal in the container.

“With a mercury vapor analyzer —a device that measures the concentration of the metal in the air— we took multiple samples and detected elevated levels. That’s why we used protective suits and masks: inhaling it is dangerous,” he told this outlet.

Fernández warned that smuggling networks are increasingly creative: “There are cases where mercury was hidden among coffee beans, iron pipes, paint cans, or mixed with dust.”

The demand largely comes from illegal mining in the South American Amazon, according to the expert. “To extract one ton of gold from rock or sediment, an average of 2.5 tons of mercury is required,” he said.

While the Peruvian customs agency estimates that the shipment from the seized container in Callao, once processed, “could yield roughly four tons of liquid mercury,” public prosecutor sources told this outlet that the exact quantity is still under investigation.

According to public prosecutor sources, the seized container remains in custody of the state. customs agencys and is still stored at DP World Logistics in the port of Callao, where it was received. It has not been moved due to its size and the contamination risk it poses.