The Xunta de Galicia confirmed this Monday that the material collected in the Galician sandbanks is not toxic. It is PET (polyethylene terephthalate), does this provide relief in the face of its possible impact on marine flora and fauna?

It should be noted that the problem does not lie in the type of plastic, but in the type of additives or chemicals that that plastic may have and that is not known at the moment. Like the Xunta, we also took samples to find out what compounds it had because the type of plastic does not tell us anything in itself. It is these compounds that could be toxic to marine fauna, affecting their growth and reproduction.

That incidence will then be known more in the long term, right?

Clear. Now, the most immediate impact occurs as a result of the accumulation of these pellets in the sandy areas. If there are many of them together, there is a risk that some marine organism and even a bird may also eat them, which will cause damage to the digestive tract. However, this could only occur due to a large amount of pellets being piled up. As I said before, to talk about the medium-long term effects, it is necessary to know the chemical compounds present in these balls.

A second aspect that is also of concern is the biodiversity of the sandy areas, which is very important for many species. And how can it be affected by this arrival of pellets?

In this regard, I have to point out that at this moment I am more concerned about the way in which the pellets are being removed than about the presence of pellets in the sandbanks. There is no unified protocol and there are volunteers, who obviously have to be thanked for their work, who are using rakes for example. If many people do this on a beach, the environmental impact is terrible. The Xunta would have to establish a protocol for all beaches with the best way to remove these microplastics, because they can get buried when passing over them, there are protected areas where people step… So I am worried about the sudden impact of many people on the sandy areas to try to remove them, being clear that the presence of these pellets is obviously not good and represents pollution.

“At this moment I am more concerned about the way in which the pellets are being removed than about the presence of pellets in the sandbanks”

However, now the challenge cannot be other than cleaning the sandbanks…

Indeed, that is the problem that we face in the medium term. You have to understand that it is not a biodegradable material. As time goes by, they will become smaller and smaller, even becoming nanoplastics, which will make their removal even more difficult, allowing them to remain in the middle, I won’t say forever, but for many, many years. With respect to the beaches, it also depends on many factors: the tides, the currents, those that are already in the sand… But I insist that there is no easy way to remove them, at least I don’t know one.

In fact, the volunteers themselves were struck by the large amount of small plastics they found in the sandbanks, which had nothing to do with this dumping.

There are them everywhere, it’s true. In fact, the UN has already warned that in 2050 there will be more plastic in the sea than fish. If we sample tap water, we will likely find plastics as well. They are obviously not bad for human health in small quantities. What I want to exemplify with this is that removing what we see these days on the beaches is going to be very, very difficult to remove because, in fact, there is no way to do it.

Beyond the environmental impact there is also the economic impact, due to the weight that a sector such as the fishing industry has in Galicia. Could there be consequences?

Precisely, I consider that the impact may be higher in the economic aspect than in relation to the environment. Fish and bivalves (depending on size) can ingest these plastics and they could be present throughout the food chain. So, of course it can end up being a problem for the people who make a living from this, obviously.

“What we see these days on the beaches is going to be very, very difficult to remove because, in fact, there is no way to do it”

Precisely, in shellfish farming we are starting from a terrible season. Could the presence of these plastics in the intertidal zones where professionals work make the situation even more difficult?

The case of bivalves, as I mentioned before, is different from that of fish, mainly because they can only ingest them when they break down for different reasons and are smaller. The smaller the pieces and the deeper they are located in the sand, the more likely they are to be ingested by bivalves, but this requires more time.

Although it is not harmful to humans, and especially as you said before, in small quantities, can it have any effect on consumers of seafood?

In this sense, I think not. There are studies in which microplastics have already been found in mussels, in fish, in clams… And so far, there has never been any problem, at least until now. The possibly toxic additives contained in these plastics can be lost from the moment they reach the sea until they end up in one of these organisms and finally on our plate.