Using human medicine Loading creatures from the river with dozens of different drugs

Drugs improve the quality of life for humans around the world, but they do not stay in our skin forever and end up in our wastewater. New research suggests that not only does a staggering range of pharmaceuticals enter the environment and accumulate in animals, but also rise up the food chain.

The problem of pharmaceutical pollution is largely the result of wastewater treatment facilities being unable to eliminate a growing concentration and diversity of drugs that flood into the sewer lines. Active ingredients that are still highly functional are then found in nature via runoff effluents or wastewater. Scientists are just beginning to understand the extent of ecological contamination, and a study published today in Nature Communications adds a pixel that gives sobering to the image. More than 60 different pharmaceutical compounds have been detected in Australian aquatic insect bodies, which are then passed on to their predators spiders.

The team of researchers – based in the United States, Australia and Sweden – sampled nearly 200 aquatic insects from six different streams near Melbourne, Australia, to test the presence of 98 compounds in their tissues. These compounds included many commonly used analgesics such as aspirin and ibuprofen, antibiotics and antidepressants.

Their discoveries? These insects were taking drugs …a lot of drugs. A total of 69 different drugs were detected in aquatic insects. When researchers compared insects collected between watercourse sites, they found that those in densely populated areas or downstream of wastewater treatment plants had absorbed much higher drug concentrations, up to 100 times in some cases. However, even in relatively unspoiled areas, such as streams running through national parks, drugs were detected in insects.

Alarmingly, the contamination did not stop on the stream bed. The team also sampled spiders building canvases along the banks to see if drugs were entering the food chain once the aquatic insects had matured, leaving the water and flying briefly before striking a silk trap. silky.

Unfortunately, that's exactly what they found. Researchers detected 66 drug compounds in spider tissues, often at concentrations ten times higher than those of aquatic insects. Pharmaceutical pollution, in other words, is concentrated in the food chain in a process called "biomagnification".

To get an idea of ​​the type of dosing that other animals might already have, the team examined platypus and brown trout, two species that feed on insects infused into study rivers. Using drug concentrations found in insects and estimating predator food consumption, the team estimated the dose received by predators. Antidepressants were present at much higher concentrations than others, with trout receiving nearly 30% of the daily human dose and platypus exceeding 50%.

So how difficult is it for drug-soaked creatures? Frankly, scientists do not really know what makes ubiquitous drugs at such high levels of concern. Some pharmaceuticals are already known to have an impact on the behavior and physiology of animals. Antidepressant waste makes coastal crabs less suspicious of predators and the perch becomes more agitated after being fed on insects laden with antidepressants. Amphetamines in streams influence the timing of aquatic insects becoming adults.

The ecological effects of the effects of drugs are not yet well understood. Some compounds can mix and interact in complex ways, influencing behavior to affect reproduction, or how predators catch their prey, or how prey avoids being trapped. And pharmaceutical pollution may be even more widespread than this study suggests. After all, while the team has measured about 100 different compounds, there are thousands of different drugs that are crossing markets around the world.

There are many troubling unknowns here, but one thing is for sure: if humans do not find a way to prevent their waste from spilling into the environment, the cumulative effects, whatever that is. 39 they are, will necessarily aggravate.

Jake Buehler is a science writer living on the Olympic Peninsula in Washington, worshiped the strange, wild and unrecognized tree of Tree of Life – follow him on Twitter or on his blog.