In a study of animals washed up on Britain’s shores, experts have found microplastics in the guts of every single mammal they examined. A team of researchers from the University of Exeter and Plymouth Marine Laboratory (PML) analyzed the remains of 50 animals from 10 species of dolphins, seals, and whales.
The study revealed that 84 percent of the particles were synthetic fibers, which originate in many different sources including clothes, fishing nets, and toothbrushes. The rest of the particles were fragments of food packaging and plastic bottles.
“It’s shocking – but not surprising – that every animal had ingested microplastics,” said study lead author Sarah Nelms. “The number of particles in each animal was relatively low (average of 5.5 particles per animal), suggesting they eventually pass through the digestive system, or are regurgitated.”
“We don’t yet know what effects the microplastics, or the chemicals on and in them, might have on marine mammals. More research is needed to better understand the potential impacts on animal health.”
The animals examined for the study had died of a variety of causes, but the researchers noted that those who died from infectious diseases had a higher number of particles than those who died from other causes.
“We can’t draw any firm conclusions on the potential biological significance of this observation,” said study co-author Professor Brendan Godley. “We are at the very early stages of understanding this ubiquitous pollutant.”
“We now have a benchmark that future studies can be compared with. Marine mammals are ideal sentinels of our impacts on the marine environment, as they are generally long lived and many feed high up in the food chain. Our findings are not good news.”
Dr. Penelope Lindeque is the head of the Marine Plastics research group at Plymouth Marine Laboratory.
“It is disconcerting that we have found microplastic in the gut of every single animal we have investigated in this study,” said Dr. Lindeque. “Indeed, from our work over the years we have found microplastic in nearly all the species of marine animals we have looked at; from tiny zooplankton at the base of the marine food web to fish larvae, turtles and now dolphins, seals and whales.”
“We don’t yet know the effects of these particles on marine mammals. Their small size means they may easily be expelled, but while microplastics are unlikely to be the main threat to these species, we are still concerned by the impact of the bacteria, viruses and contaminants carried on the plastic.”
“This study provides more evidence that we all need to help reduce the amount of plastic waste released to our seas and maintain clean, healthy and productive oceans for future generations.”
The research is published in the journal Scientific Reports.
By Chrissy Sexton, Earth.com Staff Writer
Image Credit: Frazer Hodgkins & CSIP