Marine debris has a devastating effect on aquatic life, the environment, our economy and ultimately – our health. This plastic tsunami, if left unchecked, not only threatens the life of marine creatures, birds and fish, but our way of life too. The sea has become a melting pot of plastic, of which particles are increasing dramatically year on year. Entanglement and ingesting plastics causes the starvation or suffocation of thousands perhaps, millions of marine animals and birds.
An Unhealthy Cocktail of Chemicals
Plastics are known to leach chemicals into the ocean as they break down. They also disintegrate at lower temperatures than previously thought. Chemicals such as Bisphenol A (BPA), a structural component in polycarbonate beverage bottles and in metal food can inner coatings, has been causing concern within our marine environment for years and its use has recently become more carefully regulated. Manufacturers have largely replaced BPA with Bisphenol S (BPS), which researchers are now discovering is equally as problematic as BPA.
BPA imitates the hormones in our bodies and has been linked to a variety of health problems, including breast and prostate cancer, obesity and low sperm count in human adults.
Much research has gone on into BPAs effects on the human body, but finding conclusive results have proven difficult as this ubiquitous compound is found in many products making it difficult to isolate its effects. Even BPA-free plastics were found to release chemicals which had even more Endocrine Activity (EA) than BPA containing products. This EA is capable of seriously affecting reproduction in fish and shellfish. In tests on mice BPA has been found to make male species less ‘male’ and as a result less attractive to females. Although there is some discussion as to whether the research has found conclusive evidence or not it has led to the US Food and Drug Administration (FDA) banning the use of BPA in children’s feeding bottles and cups. BPA has a potential danger to growing bodies and new research suggests that the chemical could be harming children’s kidneys and hearts. A certain amount of the chemical is known to migrate into our food within the can, but more of it is released when the polymers used in its production breakdown and has this major health implications for humans, particularly children. The growing body is particularly vulnerable and the fact that BPA is detectable in urine is testament to the fact that it passes through our organs.
Until 2010 the FDA said that BPA was safe. The agency altered its position in 2012 and when it suggested that children’s feeding bottles and cups should be BPA free. The FDA maintains that studies using standardised toxicity tests have shown BPA to be safe at the current low levels of exposure. But, based on other evidence, largely from animal studies, they expressed ‘some concern’ about the potential effects of BPA on the human brain, behaviour, and prostate glands in foetuses, infants and young children.
Phthalates, another family of chemicals makes plastic pliable, so therefore they are everywhere and, like BPA, they carry a health warning and researchers have linked phthalates to asthma, attention-deficit hyperactivity disorder (ADHD), breast cancer, obesity and type II diabetes, low IQ, neuro-developmental issues, behavioural issues, autism spectrum disorders, altered reproductive development and male fertility issues.
Our oceans are vital to our survival. They provide half of the world’s oxygen and play a massive part in regulating our climate. Nearly 50% of our current species worldwide are supported by our seas. Within the next 10 years, our seas could contain one kilogram of plastic for every three kilograms of fish.
Our rubbish is trapping, poisoning and suffocating our precious sea species. So what is it doing to us?
A Few Hard Facts
Hazardous substances leached from plastics are toxic to plants and animals and do not break down naturally. Many of these have endocrine disrupting properties.
These chemicals can accumulate through the marine food chain and pose health risks to humans.
If allowed to accumulate in the food chain these chemicals pose a risk to humans consumption of contaminated sea food. A shocking 58% of the assessed commercial fish stocks are not in good environmental shape
Land-based activities seem to generate most of the marine litter in the Mediterranean, Baltic and Black Sea. In the North East Atlantic, the main cause of marine litter is tourism and recreational activities together with diverse maritime activities, particularly fishing and shipping.
The first worldwide estimate of the mass of land-based plastic waste entering the oceans estimated that in 2010 out of 275 million metric tonnes of generated plastic waste between 4.8 million and 12.7 million ended up in the ocean (Jambeck et al, 2015). As many as 5.25 trillion particles have been estimated to be floating in our oceans (Eriksson et al 2014).
Beaches of Plastic?
Not only that, according to researchers in Plymouth and Southampton, microscopic bits of plastic have moved unseen throughout the marine environment and when collected from UK beaches, estuaries and shallow waters, a third of it has been identified as synthetic polymers used in plastics. Plastic is becoming so widespread it is becoming the beach itself. (Exert from an article by James Owen for National Geographic magazine).
Recent evidence shows that harmful chemicals resulting from ingestion of micro-plastics can accumulate in the tissues of large filter feeding animals such as sharks and whales (Fossi et al 2014). The high abundance of microplastics can confuse smaller filter feeders which feed on plankton and the base of marine food webs.
According to the European Environment Agency (EEA Report no. 2/2015), On average, 712 items per 100 m stretch of beach were recorded in recent assessments. Volumes (in kg) of marine litter have also been monitored, especially in the Mediterranean countries, where more than 100 kg/100 m stretch of beach can be found in some areas.
Plastic is the dominant litter material in European seas. Over 50% of the plastic litter is packaging waste, particularly plastic bottles (ARCADIS 2013). this type of debris has also been found in great quantity on the sea floor.
Over 650 marine species inhabit European seas. However, species and habitats assessed from 2007 to 2012 in Europe show that 66% of marine habitat assessments and 27% of marine species were considered to be threatened. This, if allowed to continue at its present rate, will result in an irreversible loss of ecosystem resilience.
We rely on our marine environment. So what can we do about it?