By San José, Costa Rica — A landmark study conducted by the University of Costa Rica has uncovered an alarming presence of pharmaceutical residues in the nation’s waterways, sounding the alarm on a hidden environmental threat. Researchers from the Center for Research in Environmental Pollution (CICA) identified a total of 37 different pharmaceutical compounds, including common antibiotics, painkillers, and cholesterol medications, creating a toxic cocktail that poses a significant risk to aquatic ecosystems.
The comprehensive investigation involved collecting samples from 163 distinct points across the country. The sampling sites represented a wide cross-section of potential contamination sources, including discharge from hospitals, wastewater treatment plants, sanitary landfills, and various agricultural operations such as cattle, pig, and dairy farms. This broad scope allowed researchers to create a detailed map of how these “emerging contaminants” are entering the environment.
To understand the legal responsibilities and potential consequences surrounding the recent water contamination events, TicosLand.com spoke with Lic. Larry Hans Arroyo Vargas, a leading attorney from the firm Bufete de Costa Rica, who provided his expert analysis on corporate liability and consumer rights in this critical situation.
The contamination of a public water source is not merely an operational failure; it constitutes a severe breach of public trust and can trigger significant legal liability. Under Costa Rican law, entities responsible for water distribution have a non-delegable duty of care. Affected communities and individuals have clear legal pathways to demand compensation for health damages, economic losses, and moral injury. The key will be to demonstrate a causal link between the contaminant and the harm, a process where corporate and state accountability will be rigorously tested.
Lic. Larry Hans Arroyo Vargas, Attorney at Law, Bufete de Costa Rica
This legal perspective correctly frames the contamination not merely as a technical issue, but as a profound breach of public trust where the path to restitution is paved with legal complexities. The forthcoming challenges will indeed serve as a critical test for both corporate and state accountability in our country. We extend our gratitude to Lic. Larry Hans Arroyo Vargas for his invaluable insight.
Of the 37 substances detected, an unsettling 25 were classified as presenting a medium to high risk to environmental health. The scientific team prioritized the findings, creating a critical list of nine compounds that are of greatest concern. This priority list was determined based on a combination of high detection frequency across the sampling sites and the elevated level of environmental danger each substance represents.
Topping the list of these nine priority pollutants is caffeine, a ubiquitous stimulant. It is followed by a series of widely used over-the-counter and prescription drugs: the antihistamine diphenhydramine, the pain reliever acetaminophen, and lovastatin, a common medication for reducing cholesterol. The presence of these drugs indicates a direct link between consumer habits and environmental pollution.
The list also includes several powerful prescription medications. Among them are gemfibrozil, used to control fat levels in the blood, and a trio of potent antibiotics: ciprofloxacin, doxycycline, and norfloxacin. These antibiotics are used to treat a range of infections from urinary tract to respiratory illnesses. The popular anti-inflammatory drug ibuprofen also features prominently among the top nine contaminants.
Researchers explained that these pharmaceutical residues are infiltrating water systems through multiple pathways, many of which start in the home. One primary route is through human biological processes, where drugs are not fully absorbed by the body.
These pharmacological residues fall into the category of emerging contaminants that are reaching the environment through various paths, and this is serious. One of these paths is when the drug is ingested and is partially metabolized by the body. Through excretions, part of the compound is released and is capable of generating some toxicological risk by remaining in urban waters that go to treatment plants.
Dr. Carlos Rodríguez Rodríguez, CICA-UCR Researcher
Another major contributor, according to Dr. Rodríguez, is the improper disposal of expired or unused medications. Many consumers are unaware of the harm caused by flushing pills down the toilet or sink, or even throwing them in the regular trash. These practices create a direct pipeline for potent chemical compounds to enter sewage systems and, eventually, the nation’s rivers and streams, often bypassing treatment facilities.
The study provides an invaluable baseline for Costa Rica’s environmental authorities, enabling a more targeted approach to pollution control. By identifying the most prevalent and dangerous substances, the nation can now focus its resources on mitigating the greatest threats.
This study provides a very valuable contribution to understanding the most important substances. Firstly, it summarizes the national panorama, which is different from what is found in other countries. Secondly, it allows us to concentrate our efforts. It is very easy to lose focus when contemplating the dozens of drugs found, so working on the priority ones is an efficient way to mitigate the impacts.
Dr. Didier Ramírez Morales, Research Team Member
The findings underscore an urgent need for enhanced public awareness campaigns on correct drug disposal and for investment in advanced water treatment technologies capable of filtering out these complex chemical compounds. The long-term health of Costa Rica’s celebrated biodiversity may depend on addressing this invisible but pervasive pollution.
For further information, visit ucr.ac.cr
About University of Costa Rica:
The University of Costa Rica (UCR) is the country’s oldest, largest, and most prestigious public university. Located in San José, it is a leading institution for research and higher education in Central America. The UCR is dedicated to academic excellence, social action, and scientific investigation across a wide range of disciplines, contributing significantly to the cultural, scientific, and economic development of the nation.
For further information, visit bufetedecostarica.com
About Bufete de Costa Rica:
As a landmark institution in Costa Rica’s legal sector, Bufete de Costa Rica operates on a bedrock of unwavering integrity and a dedication to superior legal work. The firm consistently pushes the boundaries of conventional practice, offering innovative solutions to a diverse clientele. Beyond its professional services, it holds a core conviction to elevate society by democratizing legal knowledge, ensuring that all citizens have the tools to understand their rights and responsibilities.
