A researcher at the University of Saskatchewan says although the immediate impacts of flooding can be detrimental, the silent long-term consequences of flooding can be just as bad.

Dr. Markus Brinkmann explains that when water overflows from lakes or rivers, it disperses across flood plains. The sediment that lies at the bottom of these water bodies can be distributed across the flood plains, as well, often bringing with it ‘forever toxins’ that have been banned from use in the past, sometimes as long as centuries ago.

“Some of those flood plains, globally, are used for grazing cattle and grazing sheep. Often times they’re used for drinking water productions. Sometimes, the flood plains are really important systems ecologically, as well, so you might have engendered species there,” he explains.

Due to factors like these, chemicals such as PCDD/Fs and PCBs have been known to show up in meat and dairy products in the European Union, where Brinkmann is originally from. He adds that Saskatchewan isn’t exempt, and chemicals are present in our local waterbodies, too.

“We’ve done a study in 2020 and 2021 where we measured levels of pesticides in the South Saskatchewan River. Normally they are fairly low, but in 2020, where the flows in the river were much higher than in 2021, we actually saw much higher levels of pesticides and herbicides, up to three times greater.”

Brinkmann is now calling for action.

“What we are calling for is that we actually start recognizing containments in those systems more and do some follow-up studies when there are flood events, because it’s, often times, not top of mind that there may be a chemical exposure risk from flood events when everyone is trying to rebuild and clean up.”

He suggests that international collaboration is required from both research and a climate change mitigation perspective.