A new “golden triangle” of fentanyl and gun trafficking between Mexico and the US ties together the homicide and overdose crises of the two countries, according to a a new study.
The triangle spans Baja California, Sinaloa and Sonora – the three states where almost all fentanyl seizures in Mexico take place – and connects to Arizona through a quieter part of the US-Mexico border that has become a hotspot for trafficking in both directions.
The rise of fentanyl, a synthetic opioid, has swept away the old golden triangle of Sinaloa, Durango and Chihuahua, which for decades was the epicentre of heroin production in Mexico.
Data from Mexico’s defence ministry spanning 1990 to 2024 show that 92% of seized fentanyl powder was in Baja California, Sinaloa and Sonora, while the figure for fentanyl tablets was 96%.
This overwhelming concentration of seizures could reflect the Sinaloa cartel’s dominance of fentanyl production and trafficking, thanks to access to chemical precursors through Pacific ports, economic integration across the border and “decades of experience”, said the new report by the Global Initiative against Transnational Organised Crime thinktank.
But it could also reflect the focus of law enforcement efforts, with the Sinaloa cartel in the crosshairs of both US and Mexican authorities.
There is a similar skew in seizures on the border itself, where according to Customs and Border Protection (CBP) data, roughly half of the fentanyl seized entering the US is caught coming through ports of entry in Arizona, and much of the rest comes through California.
In the other direction, Arizona’s role in gun trafficking has also soared in recent years, as was highlighted by the Mexican government’s lawsuit against five gun shops there.
Between 1 January and 24 July last year, Arizona was the source of 57% of guns that were recovered in Mexico and traced to a purchase in the US less than a year earlier, which is a key indicator of whether a firearm was bought with the intent of trafficking.
The prominence of the Arizona-Sonora border in both fentanyl and gun trafficking “underscores the linkages between the two markets”, said Cecilia Farfán-Méndez, lead author of the report.
It also links the epidemics of homicide and overdose deaths in two countries, through a vicious cycle in which revenues from drug sales in the US allow criminal groups to boost their firepower in Mexico.
Mexico’s homicide rate is among the highest in the world, at 24 per 100,000. Roughly 70% of homicides in Mexico are perpetrated with a firearm – and more than two-thirds of firearms recovered from crime scenes and submitted to tracing were sourced from the US.
But in the US, the overdose death rate is similarly high, at 21.5 per 100,000 people. And the majority of overdose deaths are caused by fentanyl.
Some states, like West Virginia, have overdose deaths rates on a level with the homicide rates of the most violent states in Mexico.
“Narratives that [place] casualties and costs of the war on drugs predominantly in the Global South are inaccurate in the context of synthetic opioids and, in particular, fentanyl,” wrote the authors. “The result is a region, not just one country, with high levels of excess mortality.”
Mexico has been under intense pressure to show that it is tackling fentanyl trafficking, with the Trump administration designating six Mexican organised crime groups – including the Sinaloa cartel – as foreign terrorist organisations (FTOs).
One thing the FTO designation could be used for is to prosecute individuals involved in firearms trafficking who demonstrably provide “material support” to such groups in Mexico.
But for now, despite a recent fall in seizures of fentanyl on the border, the situation in the US remains unchanged.
“There’s no shortage or price changes reported [in the US],” said Farfán-Méndez. “And that suggests we don’t have any less fentanyl.”
