Health · Medical Research · 2 days ago
Study finds cocaine in five rivers in Rio de Janeiro
Researchers tested water from five rivers and canals in Rio de Janeiro over a year.
Cocaine was found in 59 of 60 samples, and a substance produced when the body processes cocaine was found in all 60.
In tests, exposure to these substances harmed fish embryos.
The findings raise concerns about pollution in rivers that flow into Guanabara Bay.
A study by the Oswaldo Cruz Institute found cocaine in water samples from five rivers and channels in Rio de Janeiro and its metropolitan area.
Researchers collected more than 60 samples monthly from 2022 to 2023; only one sample did not contain cocaine, while all tested positive for benzoylecgonine, a substance produced when the body processes cocaine.
Contamination was higher during the rainy season, from October to March, and reached its highest recorded level in January.
The five waterways studied were the Irajá and Carioca rivers and the Cunha and Mangue channels in Rio de Janeiro city, and the Meriti River in Duque de Caxias.
Tests on zebrafish embryos found that exposure to the substances caused deaths, deformities, and cardiovascular and neurological changes.
A second phase examined 13 rivers, with results expected in the first half of 2027.
- Who
- Researchers at the Oswaldo Cruz Institute, coordinated by Enrico Saggioro
- What
- A study detected cocaine and benzoylecgonine in waterways and tested their effects on zebrafish embryos
- When
- Water samples were collected from 2022 to 2023; the findings were announced on October 7
- Where
- Five rivers and channels in Rio de Janeiro city and Duque de Caxias, Brazil
- Why
- To investigate water contamination and its potential effects on aquatic organisms
This story does not have two clearly opposing sides.
No direct quotes in the coverage so far.
Researchers collected monthly water samples from five waterways.
The study found higher contamination during the rainy season.
The highest contamination peak was recorded during the holiday and vacation period.
Researchers collected samples from 13 rivers for the study’s second phase.
The analysis of the second-phase samples is expected to be completed.
- Waterways in the first study
- Irajá and Carioca rivers, Cunha and Mangue channels, and the Meriti River
- Samples
- More than 60 samples were collected; one did not contain cocaine, and all contained benzoylecgonine.
- Season with higher contamination
- October to March
- Second phase
- Samples from 13 rivers were collected between December 2023 and November 2024.
- Research publication
- The findings were published in the journal Aquatic Toxicology.
Sources
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