These plants are common enough to represent a latent threat to public health.
En los márgenes del conocimiento oficial, un estudiante de química de la Universidad de Chile ha trazado el contorno de un peligro silencioso: dieciséis especies vegetales nativas y endémicas cuya toxicidad documentada aún no ha sido reconocida formalmente por las autoridades sanitarias del país. El trabajo de Bastián Caro no descubre plantas desconocidas, sino que cierra la brecha entre lo que la ciencia ya sabía y lo que el Estado aún no ha querido —o podido— nombrar. La muerte de un hombre en Valparaíso en 2025, tras consumir accidentalmente palán-palán, convierte esta omisión burocrática en una cuestión de vida y muerte.
- Una lista oficial de plantas tóxicas que lleva años sin actualizarse deja a la población expuesta a especies comunes que crecen en jardines, bordes de camino y parques de todo Chile.
- El caso más urgente es el palán-palán: una planta de flores amarillas cuyo alcaloide anabasina puede provocar paro cardiorrespiratorio, y que en 2025 mató a un hombre de 57 años en la región de Valparaíso sin que figurara en ningún registro oficial.
- Bastián Caro pasó meses cruzando textos históricos, bases de datos científicas y consultas con toxicólogos para construir un expediente sólido sobre doce especies nativas y cuatro endémicas con efectos hepatotóxicos, neurotóxicos o paralizantes.
- El matarratones —usado históricamente como veneno para roedores— contiene tutina y coriamirtina, compuestos que inhiben receptores del sistema nervioso central y pueden resultar letales para humanos, pero tampoco aparece en la lista oficial.
- Caro entrega ahora al Instituto de Salud Pública la evidencia necesaria para actuar; la pregunta que queda abierta es si la voluntad institucional estará a la altura de los datos.
Un estudiante de química de la Universidad de Chile ha reunido la evidencia necesaria para demostrar que dieciséis especies vegetales nativas y endémicas del país merecen un lugar en el registro oficial de plantas tóxicas. Bastián Caro dedicó su tesis de pregrado a revisar sistemáticamente textos históricos, bases de datos científicas y consultas con especialistas, identificando doce especies nativas y cuatro endémicas con documentación suficiente de sus efectos tóxicos sobre el organismo humano.
El peso de su investigación se hace más concreto a la luz de un hecho reciente: en 2025, un hombre de 57 años murió en la región de Valparaíso tras consumir accidentalmente palán-palán, una planta de flores amarillas que aún no figura en la lista oficial del Instituto de Salud Pública. El alcaloide anabasina que contiene imita inicialmente la acción de la acetilcolina en el sistema nervioso antes de provocar parálisis muscular y, en este caso, paro cardiorrespiratorio. La muerte ilustra con precisión dolorosa la brecha que Caro busca cerrar.
La mayoría de las dieciséis plantas identificadas produce daño hepático o efectos neurotóxicos. Entre ellas destaca el matarratones, empleado históricamente como veneno para roedores, cuyos compuestos tutina y coriamirtina inhiben receptores de glicina en el sistema nervioso central con potencial letal. No se trata de descubrimientos botánicos: son plantas conocidas, comunes, que crecen en las regiones central y norte del país, y que el propio Caro ha encontrado durante trabajo de campo en la comuna de Pirque.
Chile posee una lista oficial de 48 especies tóxicas que el investigador reconoce como un estándar pionero a nivel mundial, pues pocos países han sometido sus plantas tóxicas a un rigor gubernamental equivalente. Sin embargo, ese registro no ha sido actualizado de manera sustantiva para reflejar la evidencia acumulada. Caro no solo propone incorporar las dieciséis nuevas especies, sino también modernizar los estudios de toxicidad —hoy escasos, envejecidos y limitados casi exclusivamente a caracterización química— para incluir evaluaciones reales en humanos y animales. La investigación está hecha; lo que resta es que las instituciones decidan actuar.
A chemistry student at the University of Chile has compiled evidence that sixteen plant species native to the country deserve a place on the nation's official registry of toxic plants—a list that has gone largely unchanged despite mounting evidence of danger. Bastián Caro spent months methodically reviewing historical texts, scientific databases, and consulting with toxicologists and botanists to build his case. His work, conducted as his undergraduate thesis, identified twelve native species and four endemic ones with sufficient documentation of toxicity to warrant formal recognition by Chile's Public Health Institute.
The timing of Caro's research carries weight. In 2025, a fifty-seven-year-old man in the Valparaíso region died after accidentally consuming palán-palán, a plant with yellow flowers that remains absent from the official toxic plants list despite this fatal outcome. The man suffered cardiorespiratory arrest brought on by the plant's toxic alkaloid, anabasina, which initially mimics the action of acetylcholine in the nervous system before causing paralysis of skeletal muscles. This death underscores what Caro emphasizes in his findings: the gap between what science knows and what public health authorities have formally recognized.
Most of the sixteen plants Caro identified cause either hepatotoxic damage—harm to the liver—or neurotoxic effects that compromise the nervous system. Only two produce gastrointestinal irritation or skin irritation. Among them is matarratones, historically used as a rat poison, which contains toxic compounds called tutina and coriamirtina that inhibit glycine receptors in the central nervous system, potentially proving fatal to humans. These are not newly discovered species. Rather, Caro has assembled the necessary evidence to confirm what local knowledge and scattered scientific studies have long suggested: these plants are dangerous.
The sixteen species are distributed throughout Chile, concentrated in the central and northern regions. Caro himself has encountered several during field work in the commune of Pirque, including both palán-palán and palqui. Because these plants grow commonly and are easily accessible, they represent what Caro calls a latent threat to public health. A person foraging, a child exploring, someone unfamiliar with the flora could encounter any of them. The researcher stresses the need to educate the population about these plants to prevent accidental poisonings.
Chile's official toxic plants list currently recognizes forty-eight species—a registry that Caro notes is itself exceptional. Most countries have not subjected toxic plants to the same governmental rigor. Chile's Public Health Institute established a pioneering standard by creating a comprehensive, detailed list. Yet that list has not been substantially updated to reflect current evidence. Caro argues for strengthening the available data and reconsidering which plants warrant inclusion. He also calls for modern toxicity testing on native and endemic species, noting that existing studies are sparse, often decades old, and limited mostly to chemical characterization rather than actual toxicity assessment in humans and animals.
The implications extend beyond academic completeness. These plants are common enough that most Chileans will encounter them at some point—in a garden, along a roadside, in a park. Without formal recognition and public awareness, the risk of accidental poisoning persists. Caro's work provides the foundation for the Public Health Institute to act, but action requires institutional will. The question now is whether the evidence he has assembled will prompt the official update that public health officials have delayed.
Notable Quotes
It is necessary to strengthen available evidence to evaluate, when appropriate, updating the official list through reconsidering some species or incorporating new plants with sufficient support.— Bastián Caro, University of Chile chemistry student
Because these plants are very common to find, they represent a latent danger to public health. Therefore, it is necessary to make them known to the population to prevent poisonings.— Bastián Caro
The Hearth Conversation Another angle on the story
Why did it take a student's thesis to identify these plants? Wasn't toxicology already studying them?
The research existed, but scattered across old texts, databases, and expert knowledge. No one had systematically pulled it together for the official list. The institute had forty-eight species recognized, but the work to add more had stalled.
The palán-palán death in 2025—was that what prompted Caro's research, or did he discover the gap first?
He discovered the gap first through his methodical review. The death in Valparaíso actually validates what his research concluded: this plant is dangerous and should be on the list. It's a tragic confirmation of the risk.
Most of these plants cause liver or nerve damage. Is there a reason those two systems are most vulnerable?
The plants contain alkaloids and other compounds that target those systems specifically. Anabasina in palán-palán mimics neurotransmitters. Tutina in matarratones blocks nerve receptors. They're biochemically precise in their harm.
If these plants are common in central and northern Chile, how many people actually know they're dangerous?
That's the core problem Caro raises. They're common enough that people encounter them regularly, but without official recognition and public education, most people don't know what they're looking at or what it can do.
What happens now? Does the institute automatically add these sixteen to the list?
Not automatically. The institute has to evaluate the evidence and decide. Caro has provided the foundation, but institutional action requires will and resources. The question is whether a fatal poisoning and a student's careful work will be enough to move them.