Researchers Find Dangerous Levels of Microplastics in Sea Turtles' Organs

 

Researchers from the University of Manchester have discovered astonishing quantities of microplastics in the organs of loggerhead sea turtles, particularly in the reproductive organs of males. It is the first study of its kind, and if representative of the condition of the population at large, the results suggest serious potential effects on reproduction and vitality for the iconic species. 

The team obtained the remains of ten loggerheads that were caught up as bycatch in fishing nets in the Mediterranean. Musculature and vital organs in both male and female examples contained high levels of microplastics, including the liver, kidney and heart. 98.8 percent of all tested samples contained foreign particles, and 70 percent contained microplastics. 

The ultra-tiny particles measured about 15 microns, and researchers were surprised to find so many of these solid contaminants migrating from the turtles' gut into all kinds of soft tissue.  The majority of particles came from the kinds of plastic used to make synthetic clothing and packaging, notably plastic bags, which the turtles often mistake for jellyfish and consume by accident. Plastics can stay in a turtle's gut from 40-120 days, depending on the turtle's activity level and whether there are blockages caused by the plastic. The turtles may also have picked up microplastics by rooting in contaminated bottom sediment, inhaling sea air containing plastic fibers, or consuming prey that already contained contaminants. 

Reproductive organs contained an average of 15 particles per gram, ranging as high as 25. Heart tissue contained up to seven particles per gram.  

"Exposure to MPs in reproductive organs can cause reproductive toxicity, and be vectors for contaminants and additives that can disrupt the endocrine system (EDCs), such as bisphenol A and PCBs and phthalates," the researchers noted. "Microplastics accumulation can lead to a suite of sublethal physiological impacts that are likely to be far less conspicuous, and harder to detect at both the individual and population level."