Phthalates — human-made chemicals used to enhance plastics — can be found everywhere, from plastic packaging to household cleaners and cosmetics. According to a new study, you can also find them in the newly laid eggs of seagulls.
Scientists at the University of Exeter and the University of Queensland recently found phthalates in all 13 of the European herring gulls eggs they collected from sites in Cornwall on the southern coast of the UK. Each contained up to six different types of phthalate.
Reporting their findings in the journal Marine Pollution Bulletin, the researchers also say they have discovered the presence of phthalates may be associated with oxidative stress in the gulls, raising the very real possibility this pollutant may cause problems for their health. Further research, however, is needed before they can gain any insight into whether this is harming the developing chicks inside the eggs.
"Research on the impact of plastic on animals has largely focussed on entanglement and ingestion of plastic fragments. Far less is known about the impacts of plastic additives on the body," Professor Jon Blount, study author from the Centre for Ecology and Conservation at the University of Exeter, said in a statement.
"By testing eggs, our study gives us a snapshot of the mother's health – and it appears phthalate contamination could be associated with increased oxidative stress, and mothers transfer this cost to their offspring via the egg," he explained.
“Our findings suggest that mothers are inadvertently passing on phthalates and products of lipid damage – and eggs with higher phthalate contamination also contained greater amounts of lipid damage and less vitamin E."
Phthalates are a large group of chemicals used in the processing of plastics to enhance their flexibility, transparency, durability, and longevity. They gained the name “everywhere chemicals” because they can be found, well, everywhere in the environment, including the bodies of a broad range of wild animals. You can also expect to find a wide variety of different phthalates in the urine of most humans, according to the US Centers for Disease Control and Prevention.
The precise health effects of phthalates have remained hazy in the past, but increasing evidence is starting to indicate they can have a profound effect on the health of animals. One of the main concerns stems from their ability to disrupt the endocrine system, the collection of glands that produce hormones to regulate metabolism, sexual function, reproduction, sleep, mood, etc.
Dr Shanna H. Swan, a leading environmental and reproductive epidemiologist at the Icahn School of Medicine at Mount Sinai, recently released her book Count Down on the effects of environmental pollutants on human fertility, predicting that the ever-presence of phthalates could bring some hugely detrimental mental effects to humans, from population crashes to shortened genitals.
Scientists have been loudly voicing concerns over the health impacts of phthalates and regulation is starting to be introduced in some parts of the world, namely the European Union, but they are still used widely.
As this study makes clear, the toll of plastic pollutants goes even deeper than plastic straws gathering in turtle bellies.
“We need to look more deeply into the pervasive threats of plastics – not just the breakdown of plastic items themselves, but also the dispersal of the multiple chemicals they contain,” said Professor Blount.