The Air That Enters You Does Not Belong to You

Atmosphere, lungs, blood, and cells: where does the territory end and the body begin?

Before continuing, we can try something together.

Do not change your breathing.

Simply notice your next inhalation.

Air enters.

Your chest changes shape slightly. The diaphragm moves. Air travels through the respiratory pathways until it reaches millions of alveoli. There, an extremely thin surface separates what, moments earlier, we called atmosphere from what we call blood.

Part of the oxygen crosses that boundary.

A few seconds later, it is traveling inside you.

Now exhale.

Part of the carbon leaving your lungs was not in the air that had just entered. It participated in the metabolism of cells you call your own.

Perhaps that carbon came from a fruit.

From rice.

From cassava.

From an animal that ate a plant.

And before that, it may have been in the atmosphere.

Perhaps our boundary is real.

But perhaps it has never been absolute.

Air Does Not Become Ours Because It Entered the Lungs

We usually say:

“my lungs.”

“my blood.”

“my oxygen.”

These words are useful.

But they can create an impression of ownership that physiology itself does not confirm.

The oxygen entering our organism existed before us.

During ventilation, atmospheric air reaches the alveoli. Oxygen and carbon dioxide cross the alveolar-capillary interface according to differences in partial pressure. Oxygen moves into the blood, while CO₂ predominantly travels in the opposite direction.

In the blood, much of the oxygen binds to hemoglobin.

The heart moves that blood.

Oxygen reaches the tissues, progressively leaves the red blood cells, and crosses different layers until it reaches the cells.

The journey continues to the mitochondria, where oxygen participates in oxidative phosphorylation and efficient ATP production, allowing muscles to move, neurons to maintain electrical gradients, and cells to carry out countless functions.

We can represent this descent as:

atmosphere
→ lungs
→ blood
→ tissue
→ cell
→ mitochondrion.

But that is only half of the story.

The Body Also Returns to the Planet

When we metabolize carbohydrates, lipids, and proteins, we produce carbon dioxide.

That CO₂ leaves the cells.

It enters the blood.

Much of it is temporarily transported as bicarbonate.

It reaches the lungs again.

And returns to the atmosphere.

We can complete the cycle:

atmosphere
→ lungs
→ blood
→ cell
→ metabolism
→ CO₂
→ blood
→ lungs
→ atmosphere.

Perhaps now the line separating “body” and “world” appears a little less rigid.

Matter continuously crosses our boundaries.

Imagine Just One Carbon Atom

Let us simplify even further.

Imagine one carbon atom.

It was in the air.

A plant incorporated it.

That carbon became part of an organic molecule.

You ate the plant.

For a while, that carbon entered the system we call “my body.”

It may have participated in glucose.

In fat.

In some cellular structure.

Then it was oxidized.

It became CO₂.

You exhaled.

Now it has returned to the territory.

Perhaps another plant will incorporate it.

Perhaps it will pass through another organism.

What we call “I” for a period of time is continually crossed by matter that existed before us and will continue to exist after us.

This does not mean the individual is an illusion.

The boundary exists.

But:

existing as an individual does not require existing separately.

This will be an important idea throughout this series.

Body-Territory Becomes Concrete When the Forest Burns

So far, we have spoken mainly about oxygen and CO₂.

But the lungs do not receive only what our metabolism needs.

When we inhale, we may also take in:

particles,

smoke,

pollutants,

aerosols,

pollen,

substances produced by fires.

Here Body-Territory stops sounding like only a philosophical idea.

Brazilian researchers have shown that smoke from forest fires exposes millions of people in the Brazilian Amazon to particulate matter concentrations associated with environmental health risks.

Another study published in 2023 estimated that protecting Amazonian Indigenous Lands produces effects that go beyond their territorial boundaries. Protected forests help reduce exposure to airborne particles associated with respiratory and cardiovascular disease, producing health and economic benefits for populations much larger than those living inside the territories themselves.

We can therefore follow another pathway:

forest
→ fire
→ particles
→ atmosphere
→ lungs
→ blood and tissues
→ health.

A decision made many kilometers away can physically reach another person’s Body-Territory through a single inhalation.

So How Large Is the Body?

Perhaps we can ask an apparently strange question.

Does your body end at the skin?

Biologically, the skin is an important boundary.

But maintaining that boundary depends continuously on things outside it.

Air.

Water.

Food.

Temperature.

Microorganisms.

Other human beings.

Territory.

Brazilian geographer Rogério Haesbaert develops, within a Latin American perspective, the relationship between body-territory and territory-body of the Earth, showing that territory can be understood not only as a legally delimited area, but also through lived experience, belonging, power relations, and material and affective relationships with the Earth.

Perhaps the body has limits.

But those limits are permeable.

Tekoha Does Not Simply Mean “Environment”

Here we need to be careful.

We do not want to remove a word from an Indigenous cosmology and turn it into a biomedical variable.

Izaque João, a Kaiowá Indigenous researcher, describes tekoha as much more than a geographical location. It is a space in which a way of living can be constituted, involving autonomy, family relations, spiritual practices, and territorial reconstruction.

So we will not say:

Tekoha = environment.

And certainly not:

Tekoha = an EEG or HRV signal.

Within the framework we are building, Tekoha helps us ask:

how does the place where a life happens participate in what that life can become?

Air is one of the most concrete answers.

Territorial quality changes the air.

Air changes the organism.

The organism changes how it feels, acts, and returns to the territory.

There is not only:

world → body.

There is:

world → body → world.

And APUS Is Not a Mountain Turned Into a Biomarker

The same care applies to APUS.

Recent studies in the Andes show that sacred mountains cannot be reduced to geographic accidents.

Cerro Llamocca, in southern Peru, for example, brought together human occupations, funerary practices, territorial organization, and ritual relations associated with the mountain as an apu over millennia.

Researchers from the University of Tarapacá and FLACSO have also shown that, in Andean societies, landscape, space, and ritual may involve intense relationships between humans and non-human entities, making it insufficient to treat landscape as a passive backdrop.

Therefore:

APUS is not proprioception.

It is not NIRS.

It is not EEG.

We use APUS as a conceptual lens to ask:

how far do we need to expand what we call the body in order to understand its orientation in the world?

A mountain changes:

altitude,

atmospheric pressure,

temperature,

oxygen availability,

water,

movement,

food,

social organization,

memory.

Territory changes the organism without needing to enter entirely inside it.

Confluence May Be More Useful Than Fusion

Antônio Bispo dos Santos offers another important word:

confluence.

To confluence does not mean that everything loses its identity and becomes one thing.

Different systems meet and modify each other’s possibilities without necessarily ceasing to be what they are. Recent readings of A Terra Dá, a Terra Quer emphasize precisely this form of belonging, in which humans are not simply external inhabitants of the world, but participants in relationships with other beings and territories.

Perhaps breathing is an extraordinarily simple example of confluence.

Air remains planetary matter.

You remain an organism.

But for a few seconds that air participates in what keeps you alive.

There is a boundary without absolute separation.

First-Person Consciousness Lives This Relationship Without Seeing All Its Parts

Now return to your breathing.

You do not feel every oxygen molecule crossing an alveolus.

You do not consciously perceive hemoglobin changing its saturation.

You do not follow every mitochondrion using oxygen.

And yet these relationships continuously participate in the conditions that make your present experience possible.

At BrainLatam, we have already proposed APUS and Tekoha as complementary windows for thinking about how the world enters the body and how the body returns to the world. Whole Breathing has also been used as a bridge for observing posture, viscera, metabolism, and territory without reducing them to independent systems.

Perhaps First-Person Consciousness does not mean that the world is born inside our head.

It may mean something both simpler and deeper:

everything we are able to live as reality is lived from this situated Body-Territory.

And this Body-Territory has never been alone.

The air entering now existed before you.

The carbon leaving will continue after you.

Perhaps this is why the next question in the series needs to become even smaller.

In the next blog, we will follow a single breath through four moments:

inhale,
hold full,
exhale,
hold empty.

And we will observe what happens simultaneously to the heart, RR intervals, CO₂, SpO₂, cerebral blood flow, EEG, and NIRS.

Because perhaps a single breath already contains, at a microscopic scale, the story we have followed since the first blog:

territory enters the body, the body transforms what it receives, and both continue differently after the encounter.

Main References

PETERSSON, J.; GLENNY, R. W. (2023). Gas Exchange in the Lung. Seminars in Respiratory and Critical Care Medicine, 44(5), 555–568.
Supports the explanation of alveolar ventilation and the exchange of O₂ and CO₂ across the alveolar-capillary interface.

POOLE, D. C.; MUSCH, T. I.; COLBURN, T. D. (2022). Oxygen flux from capillary to mitochondria: integration of contemporary discoveries. European Journal of Applied Physiology, 122, 7–28.
Supports the fractal descent of oxygen from capillary blood to its final use within mitochondria.

OLIVEIRA, I. N. et al. (2023). Air pollution from forest burning as environmental risk for millions of inhabitants of the Brazilian Amazon: an exposure indicator for human health. Cadernos de Saúde Pública, 39(6).
Shows concretely how changes in the Amazonian territory, especially wildfires, become respiratory exposure for millions of Body-Territories.

PRIST, P. R. et al. (2023). Protecting Brazilian Amazon Indigenous territories reduces atmospheric particulates and avoids associated health impacts and costs. Communications Earth & Environment, 4, 34.
Connects Indigenous territorial protection, air quality, and health, showing that conserving forests can generate respiratory and cardiovascular benefits far beyond their borders.

JOÃO, I. (2023). Autonomia Kaiowá e Guarani: a ação dos nhanderu e nhandesy na criação dos tekoha. Revista de Antropologia, 66.
Provides a Kaiowá-authored reference for understanding tekoha as a space of autonomy and a way of life, helping avoid reducing it to the Western category of “environment.”

HAESBAERT, R. (2022). Del cuerpo-territorio al territorio-cuerpo (de la Tierra): contribuciones decoloniales. Cultura y Representaciones Sociales.
Supports a Latin American understanding of Body-Territory in which territory simultaneously involves materiality, lived experience, affect, power, and belonging.

MADER, C. et al. (2023). In the land of the apu: Cerro Llamocca as a sacred mountain and central place in the pre-Columbian Andes of southern Peru. Journal of Archaeological Science: Reports, 49, 104045.
Provides archaeological evidence of the long-standing relationship between Andean communities and a mountain recognized as an apu, supporting our decision not to reduce APUS to a physiological variable.

MUÑOZ-HENRÍQUEZ, W.; PIÑONES-RIVERA, C.; RODRÍGUEZ VALDIVIA, A. (2023). Paisaje en acción. Los estudios sobre espacio y ritual en los Andes. Disparidades. Revista de Antropología, 78(2), e018.
Shows how Andean relationships with space and landscape include ritual, agency, and relations with non-human entities, moving beyond the idea of landscape as passive scenery.

KRENAK, A. (2022). Futuro Ancestral. Companhia das Letras.
Broadens the discussion of rivers, Earth, and belonging, helping move from the idea of environment as an external resource toward continuity with living territory.

BISPO DOS SANTOS, A. (2023). A Terra Dá, a Terra Quer. Ubu Editora/Piseagrama.
Offers the concept of confluence as a relationship in which differences can meet without disappearing, helping us understand breathing as exchange without absolute fusion between body and territory.

BrainLatam (2026). APUS y Tekoha – cómo el mundo entra en el cuerpo y el cuerpo retorna al mundo.
Provides the previous BrainLatam conceptual basis for treating APUS and Tekoha as complementary windows onto Body-Territory rather than as biomarkers.

BrainLatam (2026). Respiración Entera: Puente entre APUS y Tekoha.
Connects territorial reflection to breathing and prepares the transition toward the following blogs on respiratory phases, HRV, EEG, NIRS, and bodily regulation.