A recent study on the rivers and streams of the Buenos Aires Metropolitan Area revealed the increasing presence of medications in the water. Samples were taken at different times of the year to understand how human settlements and sewage systems influence this.
The results confirmed that pollution intensifies in areas with a higher population density. The Luján, Reconquista, and Matanza-Riachuelo rivers, along with streams like El Gato, El Pescado, and Espinillo, showed detectable levels of analgesics, beta-blockers, and anticonvulsants.
Among them, carbamazepine stood out as the most persistent compound. Peaks of sildenafil appeared in summer, while medications for respiratory conditions increased in winter.
Rainfall helped dilute some compounds, although it did not prevent their persistence in the environment.
How human activities influence
Monitoring compared rural, dense urban areas and zones with different sanitary infrastructures. In agricultural sectors, only two or three substances were detected, marking a contrast with urban stretches.
In areas with a high concentration of housing, almost all analyzed drugs appeared. The highest values were recorded near treatment plants and in places without a sewage network.
In these latter cases, the influence of cesspools, clandestine discharges, and dumps with poor impermeabilization is presumed. The pattern confirms that chemical pollution is closely associated with urban growth and inefficient management of household waste.
Internationally, local levels of paracetamol were higher than usual in other regions. This behavior coincides with the high consumption of analgesics in Argentina. Differences were also observed in residues related to mental health compared to countries in the northern hemisphere.
What happens when medications reach the water
Discarded drugs improperly can pass through treatment plants without fully degrading. Many of them are designed to resist decomposition, allowing them to remain active in watercourses.
This persistence facilitates their accumulation in ecosystems already pressured by other forms of pollution. The compounds affect fish, amphibians, and microorganisms, altering hormones, reproductive behaviors, and metabolic processes.
In some cases, continuous exposure generates antibiotic resistance in bacteria present in the environment. This phenomenon becomes a sanitary and ecological threat that advances silently.
The presence of pharmaceuticals also modifies the quality of water used for irrigation and recreation. When concentrations increase, water bodies lose their self-regulation capacity. The result is a weakened ecosystem, more vulnerable to climate change and human activities.
The everyday consumption that leaves a mark
Although most medications reach the water through sewage systems, the habit of disposing of them in the trash or the toilet intensifies the problem. Incomplete packages, interrupted treatments, and frequent self-medication feed this chain.
Each waste thrown without control prolongs the presence of chemicals in the environment. What is ingested and discarded does not disappear: it continues its journey through rivers and streams that supply millions of people.
This dynamic shows how human health and environmental health are intimately interconnected. Reducing the impact requires a profound change in consumption and waste management.
