The presence of microplastics in the seas is widespread and can be ingested by various marine organisms and then transferred along the food chain, causing physical and toxicological effects on marine organisms and human health.

The problem with plastic is that it remains chemically plastic; it doesn’t return to the ecosystem. Most of it is so resistant that neither microbes in the soil nor water can break its chemical bonds. Analyzing samples of seawater and salemas (Salpida Forbes): the latter, not to be confused with the fish of the same name, are gelatinous invertebrates that feed on phytoplankton filtered from the water they pump to move. Their stomachs were a receptacle of microplastics: of the hundred salemas analyzed, 100% had microplastics in their stomachs. “It’s a surprising result,” says the oceanographer. “I was convinced that we wouldn’t find plastic in some of them, since their stomachs cleanse themselves quite quickly.” All of this has repercussions for us humans too: although we don’t directly feed on salps, they are at the base of the food chain. If a fish eats a salp, and we eat that fish… microplastics also indirectly end up in our stomachs.

Our research provides a global estimate of the amount of microplastics present on the seabed, highlighting the ubiquity of plastic: it doesn’t matter where you are in the world. This means it’s everywhere in the water. And it makes us reflect on the world we live in and the impact of our consumer habits on what is considered a pristine place. Our research has discovered that the deep ocean is a sink of microplastics.

We must ensure that the great blue sea isn’t a giant garbage dump. This is further proof that we must stop all this at the source, as well as by building large-scale filter systems with the help of graphene and syntropic nanotechnologies, which we have been pursuing for years in our LBD research.

The oceans are facing an unprecedented crisis, threatened directly and indirectly by human activities. Here are the main factors driving their inexorable decline:

• Ocean acidification, plastic pollution, overfishing, and unsustainable aquaculture practices.
• Plastic pollution
• Excessive exploitation of fishery resources
• Unsustainable aquaculture practices

Ocean Acidification

Ocean acidification, known as the “evil twin” of global warming, represents a grave threat. Since the Industrial Revolution, the massive use of fossil fuels has driven atmospheric CO2 to its highest levels in 800,000 years. The oceans absorb approximately 2.5 billion tons of carbon per year, causing a drastic drop in pH. Today, acidity is 30% higher than in 1800 and will increase 150-fold by the end of the century.

If a few species adapt, most will succumb, reducing biodiversity. The phenomenon will alter microbes, nutrients, light, and sound propagation, favoring toxic algae and altering photosynthesis. Similar events have caused mass extinctions in the past, but today the speed is unprecedented. The first victims will be coral reefs, destined to disappear within this century.

Plastic pollution

The oceans have become a huge dustbin and the most common waste is the one that best symbolizes our disposable “civilization”, plastic. According to a recent study, by 2050 the amount of plastic in the sea will be greater than that of fish, while research from 2015 discovered that 90 percent of seabirds around the world have plastic waste in their stomachs. Every year it is estimated that eight million tons of plastic end up in the oceans, where, after having deteriorated into tiny fragments, it is ingested by marine organisms, then moving up the entire food chain until it reaches our plates. Plastic waste causes the death of 1.5 million animals every year. According to a recent study, 690 species are threatened by waste present in the sea, of which 17 percent are in danger of extinction.

Overexploitation of Fish Populations

Over the past 45 years, we have lost half of our marine fauna, primarily due to overfishing and unselective fishing. Aggressive methods such as trawling and longlines exploit the sea beyond its limits, leaving nearly a third of fish stocks at biologically unsustainable levels.

Added to this is the tragedy of “bycatch,” marine creatures caught by mistake but inevitably killed by modern fishing systems. This silent slaughter exterminates birds, turtles, whales, and dolphins, also wiping out 90% of large predators such as sharks and tuna.

Unsustainable aquaculture

Aquaculture, or fish farming, is proposed as an alternative to excessive pressure on fish populations caught in the wild. In reality, this practice also has a significant and specific environmental impact. The development of aquaculture has polluted the surrounding waters with waste materials and spread diseases among fish farms. “But the fish farming industry also decimates wild fish populations…Farms generally raise carnivorous fish such as salmon and rely on wild-caught fish to feed farmed fish.” In this way “fish farms consume much more fish than they can offer”. Precious ecosystems are also being devastated to make room for farms; hundreds of thousands of hectares of mangroves and coastal marshes around the world, for example, have been transformed into fish and shrimp farms.