Do We Really Know Where Ocean Pollution Comes From?

Most of us probably think we know the main sources of pollution in our oceans; plastic blown in by the wind or carried downstream by rivers, large oil spills caused by shipping incidents, abandoned fishing gear and chemicals washed off the land. Yet multiple recent news stories have revealed some lesser-known sources of pollution, ones which are not so obvious but still have the ability to cause extensive damage to our beautiful underwater ecosystems; let’s take a closer look at some examples. 

It turns out that our old bad habits haven’t been buried for good and are actually coming around to get us as historic landfill sites are reappearing on our beaches. As cliffs erode with each lap of the waves, our coastlines move inland and in the process, forgotten buried landfills are appearing with their contents spilling down the cliff face and landing on beaches where decades old trash can be swept away into the sea. For example, the beaches of Lyme Regis and Charmouth on England’s south coast are famous spots for fossil hunters searching for ammonites but as the cliff retreats, household garbage is now a much more likely find as chunks of plastic, metal and concrete poke out from the cliff. The receding cliff has now met the edge of Spittles Lane landfill, a site which was closed in 1978 and does not live up to today’s stricter environmental standards. Lead and asbestos are amongst many harmful substances buried in the pit which was not lined or capped back then to protect the environment as common policy was to actually allow chemicals to leach out and dilute into the soil. Scientists estimate that 6,000 cubic metres of waste have already fallen onto the shoreline in the region with another 42,000 to follow over the next century as landslides continue. Sadly, this is far from an isolated incident as in England alone, 1,200 landfills out of 20,000 are located on our coasts. In Europe, it is estimated that up to 500,000 landfills exist which predate modern waste control legislation, meaning that they have not been lined and that their contents can leak into our soil and waterways. Many of these areas are near coastlines or on floodplains and with climate change causing an increase in storms and higher sea levels, the likelihood of flooding and coastal erosion is ever growing, as is the risk of our historic waste making a reappearance. 

Already, events such as this have been seen with a storm causing the Fox Glacier landfill in New Zealand to become exposed. Old pieces of trash joined small rocks and sediment particles and were transported by the river to the coast. It is thought that this incident led to rubbish being strewn across 60 miles of coastline, yet researchers believe much more is hidden deep under the water where it is virtually impossible to clean up. Not only do these landfills contain plastic household items but also old building materials, pharmaceuticals, batteries, pesticides and industrial chemicals which are in multiple everyday products such as paint. Once in the environment, these chemicals can seep into groundwater and the soil, causing a health disaster for both the animal kingdom and ourselves. 

In order to try and prevent old landfills falling into the ocean, substantial coastal defences could be built to protect the cliffs but in some cases this comes with a high cost whilst in other cases, like in Lyme Regis, the shore is a protected area and no intervention is allowed to take place. We could excavate old rubbish dumps and move them to more modern sites however again, this is likely to be far from cost effective. Some do believe though that these sites contain useful resources, such as lithium, iron or plastic, which could be recycled and reused and the money raised from this could be used to deal with the items that really are just junk. Yet it seems the most likely solution is that the most dangerous sites will be tackled whilst the others are left and we will have to focus on moving to a circular economy as much as possible to prevent this becoming a greater issue in the future. 

Ships also produce a large amount of pollution, yet we often forget about this source because they are out of sight and out of mind for many of us as they traverse the open ocean. In February, a ship carrying an estimated £295,000,000 worth of luxury cars caught fire near the islands of the Azores. Whilst no cause has yet been confirmed, it is speculated that the lithium batteries within some of the electric vehicles onboard may have started the fire which continued for days. Once the fire was extinguished, authorities came to drag the Felicity Ace back to shore, however she took on water and sunk in the middle of the ocean, taking her luxury load, 2,200 tons of fuel and 2,200 tons of oil with her. Portuguese authorities stayed at the site to look for any signs of pollution but only a small patch of oil was sighted. This doesn’t mean that one day the vessel won’t leak pollutants into this area filled with dolphins, whales, seabirds and corals. Lying at 3,500 feet below the surface, we have very little knowledge about the condition of the ship, for example, whether the fuel tanks are still intact. And of course, the cars themselves contain many potentially polluting materials, including wires, paint and plastic. It seems that only time will tell whether the Felicity Ace will be added to the long list of environmental disasters or whether she may actually do our oceans some good, acting as an artificial reef for young corals to grow on and form a new colony. 

Unfortunately, shipping vessels losing their cargo at sea are not uncommon incidents. In fact, scientists are now arguing that container ship accidents should be viewed as seriously as oil spills due to the toxic materials many carry, such as metals, plastics and chemicals. Take the X-Press Pearl which spilt, amongst many other things, 1,680 tonnes of pre-production plastic pellets called nurdles 9 miles from the beautiful coast of Sri Lanka. Researchers thought the plastic was the worst of the damage when dolphins and fish started to wash up dead on the beaches yet for one of the first times, scientists took these tiny balls of plastic back to the lab to examine them. Their results show that harmful chemicals were coated on the surface of the plastic such as BPA which is known to cause cancer and respiratory disease. Other substances present are known to disrupt the endocrine system and hormones. Worryingly, the levels of PAHs on the plastic far exceeded safe limits for consumer products set by the EU and these tiny, almost invisible beads are now covering our coastlines and floating in our oceans. Shipping has expanded massively in recent decades as globalisation has really taken a hold, yet it seems that legislation has not kept up at the same pace as there are few regulations for the shipping of dangerous chemicals despite the damage they can cause.

Even without their precious cargo falling overboard, ships can, and do, still cause a large amount of pollution. We hear about the large oil disasters as their stories fill news headlines but what we don’t hear about is the numerous daily small spills that take place. Bilge dumping is little known by the general public yet could be a massive contributor to ocean pollution. Bilge is a mix of liquids found in the engine rooms of ships and is a cocktail of toxic substances such as lubricants, cleaning solvents and heavy metals. Ships must either treat this wastewater so it is safe to release or take it to a port, both of which are expensive. Therefore, some vessels dump bilge overboard in order to reduce their operating costs and increase profits, despite the incredibly harmful impact these substances have on wildlife. Detecting these spills is incredibly difficult however, as often vessels dump bilge at night or in rough seas when satellite images won’t show an oil slick. In Europe, EMSA is the organisation in charge and uses these satellite images to detect oil discharges. Once a potential spill has been identified, an alert is sent to the relevant country which is then supposed to go out and observe the slick, find out the cause, take appropriate action and report back. However, EMSA only hears back in around a third of cases as countries fail to respond quickly, giving the slick time to disperse or don’t investigate at all. This issue is largely not talked about, partly because it is much less visible than large spills and also because it is not in the interests of large shipping companies to broadcast. However, with multiple small spills occurring daily, the impact of this source of pollution could be massive. Whilst we know relatively little, scientists have managed to establish that almost immediate adverse effects on the environment can be spotted, such as a decline in plankton numbers.

As you can see, many incredibly harmful sources of pollution are not as obvious as we may think and aren’t put straight in front of our eyes. It is up to us to ensure that all sources of pollution are put in the spotlight, forcing authorities to clean up their act once and for all; let’s make a stand for our oceans before we tip them over the edge.

By Neve McCracken-Heywood