Océanos, el misterio del plástico desaparecido - Documental

  • 2 months ago
El plástico forma parte de la vida cotidiana: es un material ligero, resistente y de bajo coste. Es el material perfecto, pero el problema surge a la hora de deshacerse de él. De los 275 millones de toneladas de residuos plásticos, casi 32 millones son mal gestionados, es decir que no son ni enterrados, ni incinerados, ni reciclados. Y ocho de esos 32 millones acaban en el mar.

La mayor parte del plástico que flota en nuestros océanos nunca se deteriora, simplemente se divide en pequeñas partículas invisibles al ojo humano, pero lo que ocurre con esas micro partículas es un misterio. Los científicos las buscan. Son pequeñas, la mayoría invisibles, tóxicas, y en ocasiones han formado un nuevo ecosistema.
¡Bienvenido a nuestra página web dedicada al apasionante mundo del documental! Sumérgete en un universo de historias reales, descubre la verdad oculta tras los hechos y explora diferentes culturas y realidades a través de nuestros documentales cuidadosamente seleccionados. #Documental
Transcript
00:00Lightweight, waterproof, resistant, produced to size and low cost.
00:24Plastic is irreplaceable.
00:27It is the perfect material and it is very present in our lives, but it becomes a nuisance as soon as we want to get rid of it.
00:42The world is submerged in plastic.
00:45The artist Mandy Barker collects it on the beaches and seas of the whole world.
00:52And she uses it to illustrate something that we do not see.
00:57Plastic is already an integral part of our oceans, such as algae or plankton.
01:10But, paradoxically, in our seas and oceans, sheltered from the gaze, there is only a tiny part of our plastic waste.
01:27So, what has been of them?
01:32Are they in the bottom? Have they infiltrated the food chain?
01:36Or have they fragmented into such small pieces that their track has been lost?
01:47Scientists from all over the world have gone after their track.
01:51They want to find out if plastic is modifying our ecosystem without us having calibrated the consequences.
01:58The Atlantic Ocean
02:19In the United States, in the state of Massachusetts,
02:22Kara Lavender Low runs the programs of the Ocean Education Association,
02:26which has been training its students in navigation and oceanography for 35 years.
02:37Her two ships sail the Atlantic and the Pacific all year round.
02:41Kara Lavender Low has the largest collection of plastic samples taken in the ocean.
02:46Starting from this collection, she has formulated an important question.
02:51Because we have spent so much time studying the North Atlantic,
02:55we have asked ourselves, in the area where plastic accumulates,
02:59is the amount of plastic increasing over time?
03:03But what data do we have today?
03:06According to the most recent studies,
03:08the number of plastic pieces present on the surface of the oceans would rise to 50 billion.
03:16They are everywhere, from the North Pole to Antarctica, passing through the tropical seas.
03:21Often, they are barely visible, since the vast majority of them are in the ocean.
03:26We know that more than half accumulates in the heart of the water currents
03:30formed by the sea currents, the so-called oceanic turns.
03:35To date, five areas of accumulation have been identified,
03:38two in the Pacific, two in the Atlantic and one in the Indian Ocean.
03:43They are often known by the name of the Pacific Ocean,
03:46which is the largest ocean in the world.
03:50Until now, it was thought, logically,
03:52that the amount of plastic had increased over time in those areas,
03:56but after studying its unique collection in the world,
03:59Cara has come to another conclusion.
04:04When we look at the amount of plastic in the world,
04:07we can see that it has increased over time,
04:10and that the amount of plastic in the world has increased over time.
04:15But what was interesting when we looked at the total amount of plastic
04:19that we collect in the subtropical turn,
04:21we found that the amount is stable, it is constant.
04:24We didn't see a very strong increase like we expected.
04:27We don't think that the reason is that we recycle more and more,
04:31or that we throw less plastic into the sea.
04:33Instead, we think that after floating in the ocean for years,
04:36somehow the plastic disappears from the surface of the sea.
04:40Intrigued, Cara Lavenderlow tried to determine
04:43the amount of plastic present on the surface of the oceans.
04:50Her study, the most complete to date,
04:53has thrown the figure of 236,000 tons.
04:59But this is only 1% of the amount of waste
05:02that is thrown into the ocean every year.
05:06It is surprising because there is a lot of plastic going into the ocean,
05:10but we don't know what's going on with it.
05:161%.
05:18To date, only 1% of all the plastic present in the sea is located.
05:24To give us an idea,
05:26we have to look at the production of plastic in the world.
05:29In 1950 it was 1.5 million tons,
05:32today it is around 300 million tons per year.
05:36The amount of plastic floating on the surface of the oceans,
05:39according to Cara's estimates,
05:41has no point of comparison with the amount we should find.
05:46The danger is that people think,
05:48oh, well, it's just gone, it's not a problem,
05:50because it's not in the sea anymore.
05:52When what should worry us is the unknown.
05:55If we don't know where the plastic is,
05:57we don't know if it's having other impacts
05:59that we're not aware of yet.
06:02Knowing where that plastic is
06:04has become a primordial challenge
06:06to understand its effects and role in the ecosystem.
06:16But we have to start at the beginning.
06:18How much plastic ends up in our oceans?
06:23The question has been in the air since the 1970s,
06:26but we had to wait until 2015 to get a first answer
06:30from Jenna Jambeck,
06:32an engineer specializing in waste management.
06:35Her study has lasted three and a half years.
06:39We looked at 192 coastal lines across 192 countries
06:43and a 50-kilometer buffer
06:45from where waste might get into the ocean
06:48by being washed or thrown into the ocean.
06:52And then from there we estimated
06:54the percentage of plastic that was in the planet.
06:58We quantified it and estimated that in 2010
07:02nearly 8 million tons of plastic
07:04ended up in the ocean.
07:08Of the 275 million tons of plastic waste,
07:12almost 32 million are poorly managed,
07:15that is, they are neither buried, nor incinerated, nor recycled.
07:19And 8 of those 32 million tons end up in the sea.
07:23The benefit of this study
07:25has been to estimate the magnitude of the problem
07:28and, above all, to show that it has to be solved on land,
07:32better managing our waste.
07:36According to Jenna Jambeck,
07:38if we don't do anything in 2025,
07:40there could be 10 times more plastic in our oceans.
07:53Once in the sea, it's too late,
07:55it's almost impossible to pick it up
07:57and we tend to lose track of it.
08:06However, her project is not new.
08:09She started following the plastic track about 20 years ago.
08:18One of the most emblematic characters in this field
08:21is Francois Galgani.
08:22He is a reference both for the studies
08:24to which his name is associated
08:26and for his commitment.
08:30Thanks to him, plastic has become
08:32an indicator of the quality of water
08:34within the European Union.
08:41In 1992, Francois Galgani
08:43devised a project of heterodox mission for the time,
08:46to observe the bottom of the oceans
08:48in search of plastic aboard the Nautilus,
08:51the legendary submarine of the Institute.
08:57These images went around the world
08:59and allowed Galgani to develop a model.
09:04We were in the Mediterranean,
09:0620 kilometers from the coast of France
09:08and 1000 meters deep.
09:10It was a jungle where we expected to see beautiful things.
09:13But when we arrived,
09:14there were only a lot of plastic bottles.
09:17They were from the 60s,
09:19so we thought they could last many years at great depth.
09:22One of the reasons is that there is much less oxygen
09:24and there is no light at all,
09:26elements that normally favor degradation.
09:29At those depths,
09:30the plastic is degraded much more slowly
09:32than on the surface.
09:35Submarine pilots know
09:37that they have reached the bottom when they see plastic.
09:39It is an indicator of the area
09:41in which we are when we descend a cannon.
09:44What happens is that the cannon works like a conduit.
09:47The waste tends to descend in the areas
09:49where there is less current and is deposited there.
09:52That is why we find accumulation areas
09:54in the marine depths.
10:00But these areas are difficult to access
10:02and we only know them partially.
10:05Currently, we do not know exactly
10:07the amount of waste at the bottom of the sea.
10:10It is one of the questions we ask ourselves.
10:12Are they quantities that would complete the information
10:14that we do not currently have?
10:16In any case, what is clear
10:18is that what we see is nothing more than a part.
10:28Thus, we do not know the quantity
10:30or the location of the plastics in the marine depths,
10:33but are we better informed
10:35about what happens on the surface?
10:41Are the accumulation areas really like terminals
10:44for floating plastics?
10:49At the Imperial School of London,
10:51oceanographer Eric Van Seville
10:53studies marine currents.
10:57He has been interested in the turns,
10:59those areas where half of the plastic
11:01accumulates on the surface.
11:04It is generally considered that these five turns
11:07act as a kind of terminal
11:09where the plastics finish their journey
11:11after penetrating the oceans.
11:15Eric Van Seville throws some emitter-deriving buoys
11:19into the sea that behave more or less
11:21like pieces of plastic.
11:26They illustrate the chaos of the oceans.
11:28Two buoys, released a few meters away,
11:31end up separated for several hundred kilometres
11:34after only two weeks.
11:38These data provide us with a new understanding
11:41of the accumulation areas.
11:48Recently, we discovered something important,
11:51and that is that these accumulation areas
11:53are not black holes,
11:55they are not the final destination of the plastic.
11:58The fact that a plastic particle
12:00enters one of these areas
12:02does not mean that it will remain in it.
12:04These accumulation areas have a lot of leaks.
12:07The plastic can stop one of them
12:09and then move little by little
12:11and go to stop another.
12:13All the accumulation areas are connected to each other
12:16and there is a constant movement of plastics between them.
12:19Now we understand that because of all this backsliding,
12:22any plastic particle can end up
12:24anywhere in the world.
12:31Eric models the itineraries
12:33of the plastic residues.
12:35Sometimes, depending on the place
12:37where they enter the sea,
12:39it takes 10 years to reach their first turn.
12:42During those years, they degrade.
12:48And it is that the vast majority
12:50of the plastics observed
12:52have a size less than 5 mm,
12:54that is, they are microplastics.
12:57And contrary to a very widespread perception,
13:00these accumulation areas
13:02are not at all like the plastic continents
13:05that we usually talk about.
13:07If this room where we are sitting
13:09was an accumulation area,
13:11maybe there would be 30 or 40 tiny pieces of plastic.
13:14Accumulation areas are like a very clear soup
13:17of pieces of plastic.
13:19They are not garbage islands, literally.
13:22They are not continents or anything like that.
13:29It is these microplastics
13:31that focus the attention
13:33of the scientists all over the world.
13:35They are at the heart of the problem.
13:38Because they are considerably more numerous
13:40than the macroplastics
13:42and because their ability to penetrate
13:44the environment seems infinite.
13:51We are trying to understand
13:53how different types of plastic
13:55break down in the marine environment.
13:57They are exposed to the sunlight
13:59and the turbulence of the waves and currents
14:02and somehow they go from medium-sized objects
14:04to microplastics.
14:06We don't know how long that takes
14:08and we don't know the differences
14:10between the different types of plastic.
14:12But we do know that there are two types of plastic
14:14that float in the sea,
14:16polyethylene and polypropylene.
14:18Polyethylene is used to make plastic bags.
14:21Polypropylene is used to make bottle caps
14:24or milk containers.
14:26These are products that we use every day.
14:33They're kind of straight, but they're not as...
14:35Cara Lavenderlow observes the way
14:37in which the pieces of polyethylene
14:39and polypropylene are fragmented,
14:41which seem to be the most robust.
14:49Plastics are fragmented into such small pieces
14:52that they cross the networks
14:54that scientists use to take their samples
14:56and that they have holes
14:58of just a third of a millimeter.
15:03This degradation would partly explain
15:06our inability to find them.
15:21Richard Thompson was the first
15:23to allude to this strange disappearance of plastic.
15:28He did it in 2004
15:30in an article published in the magazine Science
15:32called Lost at Sea.
15:39We were showing now pieces of plastic
15:41that were about 20 micrometers in size,
15:43or about a diameter of a human hair.
15:45Nobody had ever noticed
15:47such small pieces before.
15:49There was no record of them,
15:51and yet we were finding them
15:53all over the place.
15:55We were finding them everywhere
15:57and we were finding them
15:59in the marine debris,
16:01or rather in the plastic debris.
16:03We must bear in mind
16:05that the quantity of microplastics
16:07will continue to increase
16:09in the coming years
16:11due to the fragmentation
16:13of large-scale plastic waste
16:15that are already in the ocean.
16:17So it is important
16:19that we understand them better.
16:21We have to know where they are
16:23and where they are most abundant.
16:29These microplastics
16:31are everywhere today
16:33and at the same time
16:35they are very difficult to locate.
16:37But in 2014
16:39a very interesting clue appears.
16:43An American scientist,
16:45Rachel O'Bart,
16:47studied ice banks.
16:49She observed tiny fragments
16:51of colors in her samples
16:53and sent them to Richard Thompson.
16:59So amongst the various types
17:01of subsidies,
17:03the places where large amounts
17:05of microplastics accumulate,
17:07Rachel's data suggest
17:09that the Arctic could be
17:11an important subsidy for these particles.
17:13When marine ice is formed,
17:15these particles are concentrated
17:17inside the ice itself.
17:19That could explain why there are
17:21high concentrations of microplastics
17:23in the samples of marine ice.
17:29Extrapolating the data
17:31of the various samples,
17:33Rachel and Richard have concluded
17:35that by melting marine ice,
17:37it could release a billion
17:39plastic particles in the water
17:41from here to 10 years,
17:43which would make it
17:45one of the largest deposits
17:47of plastic waste on the planet.
17:55Thus, microplastics
17:57can be in permanent transit,
17:59but is it possible that they
18:01descend to the bottom of the oceans?
18:03No proof of that presence
18:05had ever been provided.
18:09Until in 2015,
18:11a biologist contacted Richard.
18:28So I'm here at the Museum
18:30of Natural History in London
18:32to meet with Dr. Lucy Budall.
18:34Lucy contacted me a few years ago
18:36to tell me that among the sediment
18:38samples of the depths of the sea
18:40that she had been examining,
18:42she had found some pieces
18:44of bright colours
18:46that she had found
18:48to be a little unusual.
18:50Good morning, welcome.
18:52Hi Lucy, nice to meet you.
18:54I'm Richard,
18:56and I'm here with Dr. Lucy Budall.
18:58Hi Lucy, nice to meet you.
19:00Thank you very much.
19:02Lucy Budall studies the organisms
19:04that live in the underwater mountains
19:06and in the great depths of the Indian Ocean,
19:08at depths between 300 and 3,000 metres.
19:10I was surprised initially
19:12because my aim was not
19:14to find microplastics.
19:16To be honest,
19:18I didn't even know they existed
19:20before the trip,
19:22but once I came back to the lab
19:24and I found these tiny things
19:26known as nematodes,
19:28I found some fibres in the sediment.
19:30I didn't know what these were
19:32because they had never been
19:34recorded before in the deep sea.
19:36But you can see
19:38how far they were
19:40enrolled around these polyps.
19:44In the museum's collections,
19:46Lucy teaches Richard
19:48the species of the great marine
19:50seabed, worms and corals,
19:52and how he found microplastics.
19:58Microplastics had never been
20:00observed in the bottom of the sea,
20:02and not only that,
20:04the concentrations of his samples
20:06are up to a thousand times
20:08higher than those of the surface.
20:12For Richard Thompson,
20:14this is a very important discovery
20:16as it allows a first response
20:18to the enigma of plastic disappearance.
20:20It shows that microplastics
20:22move through the water
20:24columns to reach the bottom
20:26and thus multiply the chances
20:28of affecting marine fauna.
20:30If we're thinking about the risk
20:32for marine fauna and flora,
20:34we have to measure the probability
20:36of an encounter combined
20:38with the severity of the encounter.
20:40If we knew where the plastics
20:42tend to accumulate more,
20:44we'd know where the greatest
20:46potential risks are.
20:48These are the big questions
20:50that lie behind the search
20:52for microplastics.
20:54How do they interact with the ecosystem?
20:56Are they completely passive
20:58or do they modify the balance?
21:00To what extent have they penetrated
21:02marine organisms and therefore
21:04the food chain?
21:06What are the possible routes
21:08that can lead microplastics
21:10to these organisms?
21:12Yeah, that's the question, isn't it?
21:14Would those microplastics accumulate?
21:16How long do they take
21:18to be expelled by those organisms?
21:20So three important questions
21:22but at the moment
21:24very difficult to answer.
21:34Today, these questions
21:36are raised all over the world.
21:42It hasn't been a month since
21:44an article in which
21:46a new affected species is described.
21:48In 2015, scientists
21:50listed 560 species
21:52that had ingested plastic
21:54or had been trapped in it.
21:58The figure had multiplied
22:00by two in 20 years.
22:06The vast majority
22:08of organisms are affected.
22:10From the prey
22:12to the predators.
22:16From the immense whales
22:18to the tiny plankton,
22:20the base of the food chain.
22:34Opposite the Blue Coast
22:36the vast majority
22:38of marine life
22:40has been affected.
22:44On board, Gabi Gorski
22:46and Maria Luisa Pedrotti
22:48carry out a new sampling.
22:54In 2014, Gabi and Maria Luisa
22:56were part of the expedition
22:58Tara Mediterraneo
23:00which, for seven months,
23:02surveyed the waters of this sea.
23:04The 370 species
23:06that entered the sea
23:08found plastic.
23:16They have focused on the relationship
23:18between the amount of plastic
23:20and the amount of plankton.
23:22Although it fluctuates
23:24depending on the place
23:26and the month of the year,
23:28the proportion can be disturbing.
23:30There are some myctophids,
23:32that is, some lanternfish,
23:34and the plastic.
23:36And the plastic, of course.
23:40There are places where
23:42there is a lot of plastic
23:44among the plankton.
23:46There are other places with less,
23:48but imagine the whales
23:50that come and find nothing
23:52but plastic to eat.
23:54That is the problem.
23:56With so much plastic in the sea,
23:58there is no food left for the filters,
24:00for the fish, for the whales.
24:02This is how I define the problem
24:04with my students.
24:06Do not bother to throw away
24:08the plastic bags.
24:10Better cook them and eat them directly.
24:12Because anyway, one day
24:14they will end up on your plate
24:16one way or another.
24:18An image that allows
24:20to synthesize the situation
24:22and that gives the measure of the importance
24:24of the penetration of plastic
24:26in the food chain.
24:29In the laboratory they scan
24:31each sample and separate
24:33the plastic from the plankton.
24:35For each sample they establish
24:37a descriptive file,
24:39type, nature and shape.
24:45Plastic is already considered
24:47as an integral part
24:49of the marine ecosystem.
24:51It is treated and described
24:53as any of the natural elements
24:55that biology studies.
24:57A new element that reaches
24:59another level in the food chain.
25:03The zooplankton goes up at night
25:05to feed on the surface
25:07and that is when
25:09the encounters occur.
25:11The influence of the zooplankton
25:13in the plastic takes place there
25:15and as later in the morning
25:17all that fauna descends again,
25:19there is an oscillation
25:21like an artificial lung
25:23that goes up and down, up and down.
25:25The plastic ingested on the surface
25:27is then expelled in the
25:29marine depths.
25:31Perhaps that is why there is
25:33less plastic than was expected
25:35on the surface.
25:39Thus, the microplastics
25:41have mixed in the food chain
25:43from one organism to another.
25:55Beyond this observation,
25:57what are the consequences
25:59when an organism ingests
26:01a piece of plastic?
26:03Does it go through the body
26:05without more before being
26:07expelled without undesirable
26:09effects?
26:11Or are there much more
26:13pernicious repercussions?
26:17In Toronto, the ecotoxicologist
26:19Chelsea Rockman has been
26:21working on this issue for several years.
26:23If she is so interested in plastic
26:25it is because it is not so neutral
26:27when it is in the water.
26:29In the ocean, let's imagine
26:31that it is this.
26:33There are a lot of chemical substances
26:35here, urban runoff, agricultural runoff, etc.
26:37Substances of different types.
26:39These colors represent
26:41the different types of chemical substances.
26:43And then we add the plastic.
26:45Sometimes we refer to plastic
26:47as a cocktail of contaminant substances
26:49or chemical substances
26:51because the plastic itself
26:53contains certain chemical substances
26:55that come as standard.
26:57But when released into the water
26:59it also becomes a kind of magnet
27:01that attracts other chemical substances.
27:03When it enters the water
27:05it attracts and accumulates
27:07those substances on its surface
27:09and sometimes even in the plastic itself.
27:11That is why we say
27:13that they are like cocktail chemicals.
27:15And if an animal ingests
27:17any of those substances
27:19it can transfer them to its body.
27:29Plastic not only incorporates
27:31the chemical substances
27:33contained in the water
27:35that surrounds it,
27:37it also has its own.
27:39Each plastic is unique
27:41thanks to the additives
27:43that are added to give it
27:45its characteristics,
27:47its permeability
27:49or its resistance to fire.
27:53When we studied the ocean
27:55to see what contaminant substances
27:57associated with plastic
27:59were found in animals,
28:01the ones that really stood out
28:03were fire retardants
28:05which are an ingredient of plastic.
28:07So there are plastics
28:09that by nature
28:11are more dangerous
28:13when they enter the water
28:15than other wildlife.
28:23Chelsea Rockman has proposed
28:25to evaluate the toxicological effects
28:27of microplastics,
28:29recreating as much as possible
28:31the environmental conditions.
28:39To do this,
28:41she simulates the concentrations
28:43of microplastics
28:45that we find in the areas
28:47of accumulation
28:49on the surface of the oceans.
28:51She immerses some plastic balls
28:53in seawater
28:55so that they are impregnated
28:57with environmental contaminant substances
28:59and then includes them
29:01in the food regimen
29:03of a group of fish.
29:05Here we have a fish liver.
29:07When we study a fish
29:09that is fed with plastic
29:11we see this circle
29:13in the liver
29:15which is an advanced tumor
29:17that is an epithelial adenoma.
29:19And we don't expect to see
29:21a tumor like this in a fish
29:23that is between 8 and 9 months
29:25because they are really not
29:27good enough to develop tumors
29:29in a natural way.
29:31So we think that probably
29:33the cause is the plastic
29:35combined with those chemicals.
29:37In general,
29:39there is no consensus
29:41among scientists
29:43about the impact of plastic
29:45on the body.
29:47For some it is very important
29:49while for others it is marginal.
29:51But everyone shares
29:53the same verdict.
29:55There are serious reasons
29:57for the alarm.
30:03That alarm has to do
30:05with the penetration
30:07of plastics in the food chain
30:09and it is that plastics
30:11are getting closer and closer
30:13to our table.
30:15To better understand the situation
30:17Chelsea has gone to numerous fish shops.
30:19Thank you.
30:21Do you still have the golden ones
30:23in your stomach?
30:25Yes, do you want them?
30:27Yes, that's what I'm interested in.
30:31Here you go.
30:33Enjoy your weekend.
30:35Thank you.
30:37What I'm really interested in
30:39is trying to understand
30:41if there is a link between
30:43the chemical substances
30:45present in plastic
30:47and the fish and the seafood
30:49that we eat.
30:51So recently I did a study
30:53and I purchased fish
30:55in California and Indonesia
30:57and I found plastic
30:59in about 25% of the fish
31:01and I found microplastics
31:03in the stomach of a quarter
31:05of the fish that I bought
31:07and in a third part of the oysters.
31:09Your data already point
31:11to a possible impact
31:13on our health.
31:15What are its effects?
31:17What do we know?
31:19The studies are still scarce
31:21but there is one that has given
31:23us something to talk about.
31:31Colleen Jansen
31:33directs the laboratory
31:35of environmental toxicology
31:37of Gante.
31:39Her team is interested
31:41in mussels.
31:43They have discovered plastic
31:45in all the specimens observed.
31:47Unlike the fish
31:49that we do not eat the stomach,
31:51the mussel is eaten whole.
31:53According to her study,
31:55a large mussel consumer
31:57would ingest up to 11,000
31:59Colleen Jansen has focused
32:01on PCB concentrations
32:03associated to examine
32:05its harmful potential.
32:07What we concluded
32:09is that in the worst
32:11case scenario
32:13the contribution of PCBs
32:15associated with plastic
32:17are still
32:191,000 to 10,000 times
32:21lower than the
32:23recommended rate
32:25by the World Health Organization,
32:27WHO.
32:29So,
32:31although microplastics
32:33can be a vector,
32:35it is a very minor vector.
32:39Her statements are reassuring
32:41at least in terms of
32:43the presence of contaminating
32:45substances in our body.
32:47But Colleen Jansen has not finished
32:49her research there.
32:51She wanted to know what happens
32:53with plastic when it has already
32:55been thrown out of the body.
32:57Does it remain in the stomach
32:59a while before being
33:01thrown out of the body
33:03or can it migrate to other organs?
33:05Her laboratory
33:07is one of the few
33:09that has shown that microplastics
33:11can cross the intestinal walls
33:13and migrate to the circulatory system,
33:15both the blood and the lymphatic system.
33:21Here we see microplastics
33:23on the intestinal wall.
33:25The question is whether they can
33:27move here into the tissue
33:29and when we look closely
33:31we can see that there are also
33:33microplastics here,
33:35also absorbed by the tissue.
33:43In other words,
33:45they can move to other organs
33:47without us knowing the consequences.
33:54Colleen Jansen wants to know
33:56what the effects are on humans.
34:00She is carrying out a study
34:02in her laboratory.
34:04She exposes human intestinal cells
34:06to strong concentrations of
34:08two-micrometer plastic particles.
34:10Her goal is to obtain
34:12a theoretical transfer rate
34:14and then determine the amount
34:16of particles that remain
34:18inside the body.
34:21If, for example,
34:23you really like mussels,
34:25every year there will be
34:2760 microplastics that will move
34:29from those mussels
34:31to the underlying tissues
34:33of your intestine.
34:36And, as I say,
34:38the main question right now
34:40is whether it is an important figure
34:42and whether, in the worst case,
34:44those 60 particles
34:46can have adverse effects
34:48on the human being.
34:50And, as I said,
34:52this is something that we have not yet discovered.
34:54This is something that
34:56medical doctors need to look at
34:58and try to provide answers for.
35:08The circle is closed.
35:10We throw our plastics
35:12and they end up going to stop
35:14our body.
35:16Plastics have become
35:18the object of study
35:20and have completely colonized
35:22the marine environment,
35:24to the point that there are
35:26scientists who consider
35:28that today the toxicological risk
35:30is insignificant compared
35:32to the ecological risk.
35:34Can plastics, in their microscopic variant,
35:36endanger the ecosystem?
35:46It's impressive.
35:48It's impressive
35:50the number of algae
35:52attached to these plastics.
35:58All studies are important.
36:00Studies on toxicity,
36:02on the ingestion of plastics.
36:04But the fact that there are
36:06250 billion new substrates
36:08present in the Mediterranean
36:10and have this power of dispersion
36:12among the species
36:14is amazing.
36:44A large piece of plastic
36:46from a Japanese tidal wave
36:48has ended up compensating them.
36:50Contrary to ships,
36:52which are often vectors
36:54of species introduction,
36:56plastics do not go from point A to point B,
36:58but move at the rate of the wave.
37:00Its dispersion capacity
37:02is infinite.
37:04In addition, the slowness of their movements
37:06gives time to the fauna and flora
37:08to adapt.
37:10They sometimes make rafts
37:12that are microscopic.
37:14For me,
37:16it's a clockwork bomb.
37:18It is essential to know
37:20the importance of its impact
37:22on biodiversity
37:24and even on the transfer
37:26of pathogenic agents.
37:32Impact on biodiversity,
37:34transfer of pathogenic agents,
37:36microplastics are a cause
37:38of concern.
37:40They have already begun to be studied
37:42in the Poole's Hole Marine Biology Laboratory.
37:46Since 1888,
37:48this laboratory, which can boast
37:5056 Nobel Prizes,
37:52explores fundamental biology
37:54and biodiversity.
37:58Microbiologist Linda Amaral-Seder
38:00has included plastic
38:02among her research subjects.
38:04So here we have
38:06a litre of seawater,
38:08and believe it or not,
38:10there's about a billion
38:12bacteria in this sample here,
38:14and ten to the fourth
38:16microorganisms,
38:18also microbes,
38:20but they are sort of like
38:22the plants that live in the ocean
38:24that give us about half
38:26of the oxygen that we breathe.
38:28And to it,
38:30I'm going to add some pellets,
38:32so just by adding
38:34this little drop of plastic,
38:36I'm transforming this community
38:38into something we don't know yet.
38:40And that's because these kind of
38:42surfaces don't exist naturally,
38:44so this is part of the new
38:46habitat that we're trying to understand.
38:54Linda Amaral-Seder's studies
38:56and her husband Eric's
38:58focus on the organisms
39:00and the plastic waste
39:02found in the oceans.
39:06Before them,
39:08a whole world opens up,
39:10a unique world,
39:12they call it Plastisfera.
39:14Hi Eric, how's it going?
39:16Good.
39:18What have you got there?
39:20I've got one of our
39:22incubation samples.
39:24So this is the plastic
39:26in which we observe
39:28some animals,
39:30some invertebrates.
39:34And you can see the surface
39:36is a polyp,
39:38which is a colonizing animal.
39:44And you can see that
39:46it's just loaded
39:48with diatoms,
39:50but if you start zooming
39:52you can see that it's just
39:54having diatoms on the surface.
39:56Look at how many diatoms
39:58it's got, but there's
40:00all kinds of stuff.
40:02Yeah, it's covered.
40:06I don't know what that is,
40:08but I want to examine it.
40:10What is that?
40:12I have no idea.
40:14At first I thought it was a ciliate
40:16covered in bacteria,
40:18but it's not.
40:24I don't know what it is.
40:26Oh, my God.
40:28It is a ciliate.
40:30It's a ciliate, isn't it?
40:32Yes.
40:34What's interesting about this sample
40:36is that the surface is completely
40:38covered in bacteria.
40:40Each of these things is a bacteria
40:42and some of them are dividing.
40:44This one is starting to divide,
40:46that one is already dividing,
40:48so they're growing,
40:50they're not stuck together.
40:52I remember these are really tiny,
40:54they were about half the size
40:56of my little finger.
40:58We saw some viscous,
41:00full of microbial life,
41:02which was really fascinating.
41:04We found predators,
41:06prey, organisms that were
41:08parasiting other organisms,
41:10and even symbiotic organisms.
41:12This showed that it was
41:14a little self-sustaining ecosystem
41:16that was floating in the ocean
41:18and in the trash islands.
41:22This is how they revealed
41:24the existence of a separate world,
41:26an ecosystem that exists
41:28on its own,
41:30with its particular communities,
41:32different from those
41:34that develop in natural
41:36resources such as
41:38wood or algae.
41:44And among the organisms
41:46identified on the pieces of plastic,
41:48there is one that caught their attention.
41:52In one of the first
41:54microplastic samples
41:56in which we studied
41:58its bacterial community,
42:00we found that there were
42:02large numbers of vibrions.
42:04These bacteria are interesting
42:06because not all of them,
42:08but some of them,
42:10cause diseases in animals
42:12and human beings.
42:14Vibrions are sometimes
42:1625% of the microbial layer
42:18of a piece of plastic,
42:20and they are known
42:22to be carriers of cholera,
42:24which means that
42:26they are given a minimum of attention.
42:38A colleague of Linda and Eric,
42:40Tracy Minzer,
42:42has just shown that
42:44vibrions have specific
42:46fixation mechanisms
42:48and a very solid shape.
42:52These bacteria also have
42:54genetic characteristics
42:56that allow them to adhere
42:58to the intestinal tissues
43:00of fish, thus threatening
43:02marine populations.
43:04They don't really have
43:06a serious pathogen
43:08that would affect humans.
43:10And it makes sense
43:12because these bacteria
43:14do not interact at all
43:16with fish.
43:18So what we think might be happening
43:20is that the plastic
43:22perhaps is serving as a vector
43:24for these vibrions
43:26to get down
43:28and get into other fish
43:30and transmit
43:32parasitic agents
43:34or pathogens to fish shops.
43:40Microplastics become
43:42Trojan horses for
43:44pathogenic bacteria
43:46and packs for invasive species.
43:48They could be a vector
43:50of important transformations
43:52of the marine environment.
43:54Studies are in their infancy,
43:56but scientists are already
43:58warning of the threat
44:00to the balance of these environments.
44:06But by observing these
44:08microbial communities,
44:10the three American researchers
44:12found a surprising discovery.
44:16Some of these bacteria
44:18would have the ability
44:20to accelerate the plastic
44:22degradation process.
44:26A surprising discovery
44:28was that many of the microbes
44:30that we were finding
44:32in the plastic sphere
44:34had also come out
44:36in oil spills, for example,
44:38and hydrocarbons degradation
44:40and we found that
44:42that was really compelling
44:44based on the idea
44:46that microbes associated
44:48with those plastics
44:50may also have the capability
44:52to degrade plastics
44:54or those hydrocarbons.
44:56We're still looking into that,
44:58but there's some good evidence
45:00by my cross-examination
45:02that some of these microbes
45:04are capable of accelerating
45:06the weathering
45:08or the high-processing
45:10of plastics in the wild,
45:12in the open ocean.
45:24With the electron microscope
45:26we've seen some spherical cells
45:28between 2 and 4 micrometres in diameter
45:30that we call hole formers
45:32that appear to be embedded
45:34in the surface of the plastic.
45:36Whether they're metabolising
45:38or specifically breaking them down
45:40by only in the attachment
45:42we don't know,
45:44but that's one piece of evidence
45:46that they're having an impact
45:48on the plastic and perhaps
45:50breaking it down.
45:54Bacteria capable of breaking down
45:56plastic?
45:58Eric, Linda and Tracy
46:00are investigating this
46:02and they have no doubt
46:04that this is an important part
46:06of the fragmentation
46:08of plastics in the sea.
46:10But are these bacteria capable
46:12of metabolising them
46:14and thus making them disappear
46:16from our oceans?
46:28Today there is evidence of this.
46:34Here we have some pieces of plastic
46:36that have been in the sea
46:38for two months.
46:40During these two months
46:42bacteria have developed
46:44on the surface
46:46and now we're going to see
46:48if there are any bacteria
46:50that are capable of degrading
46:52the plastic.
46:54The way to demonstrate this
46:56is to introduce a piece of plastic
46:58with bacteria in a minimum environment
47:00where there is no other food
47:03What we see in these curves
47:05is a decrease in oxygen,
47:07that is, that the bacteria
47:09are eating the plastic
47:11as they are consuming the oxygen.
47:17In Banyulsurner, Jean-François Guiglion
47:19and Claire Dussoud
47:21from the Microbial Oceanography Laboratory
47:23are demonstrating that there are
47:25isolated bacteria strains
47:27that completely assimilate
47:29different types of plastic
47:31Bacteria develop
47:33a complex strategy to ingest them.
47:37A plastic is a polymer.
47:39Polyethylene, for example,
47:41is the most commonly used plastic in commerce.
47:43It is a chain of carbon and hydrogen.
47:45In these chains
47:47there is no more than carbon and hydrogen
47:49and that is a problem for bacteria.
47:53It is a problem for bacteria
47:55since in their original state
47:57plastic particles are not edible
47:59and they are too thick.
48:01Bacteria start like this
48:03sending enzymes out of their cells
48:05to oxidize them.
48:11When oxygen appears in the polymer
48:13the bacteria sends other extracellular enzymes
48:15to cut the carbon chains.
48:19There are different species of bacteria
48:21involved in this degradation process
48:23until they manage to divide it
48:25into small molecules
48:27that they can finally devour.
48:37What if bacteria explained
48:39our inability to find
48:4199% of the plastic in the oceans?
48:43Could they be a solution to the problem?
48:49Claire and Jean-François
48:51are trying to characterize
48:53these microbial communities.
48:57The degradation of plastic in the sea
48:59is complex.
49:01Dozens of thousands of bacteria
49:03come into play,
49:05although we do not know
49:07what each one does.
49:09It's good news
49:11because it means
49:13that we can select rare species
49:15and isolate them
49:17to know them better.
49:19And that's a good thing
49:21because it means
49:23that we understand
49:25that plastic degradation
49:27is a very, very slow process.
49:31So we are gradually understanding
49:33that the solution
49:35will not be the bacteria
49:37that degrade the plastic
49:39because there is so much plastic
49:41and the degradation time
49:43is so slow
49:45that the bacteria
49:47are not able to devour
49:49all the plastic
49:51that reaches the sea.
49:53Although bacteria
49:55can absorb plastic,
49:57they only explain a tiny part
49:59of that disappearance.
50:01They cannot be
50:03the miraculous solution
50:05to a problem that is still a mystery.
50:07No matter how hard we try,
50:09nature cannot adapt
50:11to our unbridled consumption of plastic
50:13or to our inability
50:15to manage the waste it produces.
50:17For a few years now,
50:19the scientific community
50:21has been trying to understand
50:23what happens when plastic reaches the sea,
50:25neglecting its outcome
50:27and its effects.
50:29Science has identified microplastics
50:31as a source of concern
50:33and is already wondering
50:35whether smaller nanoplastics
50:37are even worse.
50:39But today we are still measuring
50:41the time and degradation rate
50:43of those plastics in the oceans.
50:45We are taking the first steps,
50:47asking the most basic questions
50:49and trying to sample
50:51all the information we can
50:53to see if we can answer
50:55those questions.
50:57In most cases, we cannot.
50:59But on the other hand,
51:01we do have some answers
51:03and some knowledge
51:05about how to prevent
51:07plastic from reaching the ocean.
51:13The way to keep plastic
51:15out of the ocean
51:17is to be aware of the landfills
51:19and the waste dumps.
51:21You know, just human choice
51:23basically.
51:27So it's not about
51:29not using plastics,
51:31it's about using them
51:33much more smartly.
51:35And what I think maybe it's going to take
51:37is as a rethinking of the way
51:39we use plastic,
51:41produce plastic
51:43and the increased realization
51:45of the way we can escape
51:47from the planet.
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