Water samples from all over the country have arrived at the university, to see how many microplastic fragments they contain.
The water, from rivers and lakes, have been collected by an army of volunteer outdoor swimmers and transported in... wine bottles.
Once at the university the water-filled wine bottles are carefully analysed by Dr Christian Dunn and a team of research students for the tiny pieces of plastic floating in them.
Explaining the project, Dr Dunn said:
We wanted to look at as many different inland waterways as possible and find out how big a problem microplastic pollution is in all of them.
"So we teamed-up with Laura Sanderson, a professional wild swimmer, and the organization We Swim Wild, to come up with idea of getting other wild swimmers to send us samples in the areas they regularly swim in.
"The response has been tremendous and the volunteers - we call "Waterloggers" - have been incredibly supportive."
"We decided to use screw-cap wine bottles as the sample bottles after initial experiments showed they were just as good as some expensive laboratory bottles; plus it makes preparing the sampling equipment rather enjoyable!" Dr Dunn added.
Alongside organizing the volunteers to collect the samples, We Swim Wild has raised funds to pay for the couriering of the bottles as part of its aim to combine adventure activities with scientific research.
The project is believed to be the largest citizen science project of its kind in the UK.
Bailey Taylor, one of the students involved in the research, said: "We're getting samples sent to us from every county in the UK and it's great knowing we're involved in such a big project with some important findings coming out of it.
"Once we know the scale of the problem, in terms of how much microplastic pollution is in our waters, we can then start to plan possible ways of dealing with it."
Another student, Luke Fears, said: "Society is becoming more aware of the problems of plastic waste, but microplastics are the almost invisible side of the issue.
"Getting the public involved in a microplastic project of this scale is important not only because it allows us to collect a huge number of samples, but it also helps highlight the environmental problem we are facing."
Results from the project are expected later this year.
Bangor University is a leading research institute on plastic pollution and has created the Plastic Research Centre of Wales (PRC Wales) to bring together academics and interested organisations to investigate the issue.
Plastic pollution also features in many of the degrees in the College of Environmental Sciences and Engineering for more information visit bangor.ac.uk.