Found numerous chemicals from old tires in Osterfjorden

Particularly high occurrences of zinc and remnants of DEHP phthalate were found. This is a chemical used as a plasticizer to make plastics more flexible. The researchers also discovered the chemical N,N′-Diphenylguanidine (DPG), which is used, among other things, in tire production.

– Even after over 50 years, these chemicals remain in the environment. We have not investigated whether these chemicals have negatively affected fish or humans, but I can't imagine it’s been good to swim here, says NORCE researcher Farhan Khan, who conducted the study.

The research team took water and sediment core samples from the area with the tires and compared them with two nearby areas without tires. Besides zinc and phthalate, researchers also found unnaturally high levels of lead and copper. The highly toxic chemical ‘6PPD’, which is deadly for fish, particularly interested the researchers. The substance is used in tires to protect the rubber from degradation and prolong its lifespan, but they found no traces of it in the tire area.

– The likely explanation is that this chemical disappears very quickly from the environment.

According to Khan, this is the first time researchers have examined the occurrence of chemicals in the sea around a "tire cemetery." There are other areas in the world where thousands of tires have been dumped.

– We are not aware of other studies like this, but we certainly hope this won't be the last. These are areas we do not fully understand, so we need more knowledge about how this has affected biodiversity in the area. This can be done, among other things, by comparing the polluted area with surrounding areas.

The most well-known “tire cemetery” is perhaps ‘Osborne Reef,’ off Fort Lauderdale in Florida. Here, between 1 and 2 million tires were dumped in the 1970s in an attempt to create an artificial reef. However, the attempt failed, and it became clear that this had harmed the environment.

There has been debate over how many tire particles end up in the environment, but researchers estimate that rubber particles from tires make up nearly three-quarters of the microplastics released in Norway.

– This underscores the need for much more research on this, says Khan.

Khan has studied pollution from tires and plastics for over ten years. He has led the groundbreaking project ‘Clean Shores, Great Lakes’, which was the first major research project to study plastic pollution in iconic lakes such as Lake Victoria in Africa.

The study of chemicals from old tires was published in the journal ‘MDPI Environment’ and funded by Regional Research Fund Vestland (RFF Vestland). Read the entire study here.

Besides Khan, three other NORCE researchers, Adrián Jaén-Gil, Alessio Gomiero, and Amandine Tisserand, contributed to the study, while Lúcia H. M. L. M. Santos from the Institute of Natural Resources and Agrobiology of Salamanca and Sara Rodríguez-Mozaz from the Catalan Institute for Water Research analyzed the water samples.

Eirik Langeland, CEO of the Clean Oceans business cluster, was also central to getting the project started.