What happens to your atoms when you die? About 100 billion people have died since the dawn of humanity. Since the law of conservation of matter says that matter cannot be created or destroyed, all their atoms have to be still be around.
The two most common human practices for disposing of dead bodies is burial underground and cremation. The majority of the molecules in your body are in the form of H2O or water. This will either evaporate out of the body and into the atmosphere, or be leached out into the ground. The rate of this leaching depends on the temperature and condition of the soil and the atmosphere to which the body is exposed.
The vast majority of water even if it is in liquid form will enter earths water cycle where it will be eventually heated into steam, go up into the clouds, and come down as rain water. Much of this will eventually end up in rivers and lakes, and subsequently in your drinking water. Some of the rain water will be absorbed by plants. That water will be used in the process of photosynthesis, where the water and carbon dioxide, along with sunlight are involved in a chemical reaction that produces carbohydrates and oxygen. You and other fellow human beings will breathe this oxygen produced by plants to sustain your lives.
And what about the carbohydrates produced from the water in photosynthesis? You and your fellow animals will eat it in the form of fruits and vegetables. And guess what, in the process of metabolizing all the carbohydrate food from plants, you will produce the food for plants – carbon dioxide and water. And the cycle repeats itself.
What happens to all your soft tissues? Your soft tissues are composed of carbohydrates, fats and proteins that get metabolized with the help of about 100 trillion bacteria that live in your body. But wait, where did all these bacteria come from? And why aren’t they eating your right now? They have been living in your body all along – mostly in your gut – your small and large intestines.
Your body has a very robust immune system which keeps these 100 trillion bacteria in your body in check. However, once you die, your immune system stops working. So your bacteria now have a field day consuming all the tissues in your body. The bacteria metabolize all the soft tissues and use it for energy and reproduction.
Other gases besides Carbon Dioxide and Water vapor are also produced. Proteins in your body for example have nitrogen atoms. And these are metabolized into nitrogen oxides NO, NO2, N2O etc, and ammonia NH3 – which by the way are potent greenhouse gases. Nitrogen oxides are about 300 times more potent than carbon dioxide for example. Once the oxygen begins to run out, then anaerobic bacteria go to work. These bacteria don’t need oxygen to metabolize your tissues. But they produce Methane, hydrogen sulfide and ammonia as by products – the smelly gases.
These eventually escape the body and become part of the atmosphere. So when you go outside and smell something funny in the air, it is possible that you are inhaling atoms that came from your great grandma. Other molecules are released as nutrients into the underlying soil.
What about cremation? When we are cremated, the majority of atoms in your body which are hydrogen, carbon, nitrogen, oxygen and sulfur are turned into gases due to the high heat of the burning process. These gases enter the atmosphere in the form of water vapor, carbon dioxide, nitrogen oxides and sulfur oxides. But as you know several kilograms of a you will be in the form of ash left over from the cremation process. An interesting statistic is that your ashes weigh About the same as your birth weight.
What are these ashes composed of? Phosphate and Calcium make up your bones. So that’s where these atoms come from.
What happens to these ashes? These ashes are likely to make their way eventually to soil, where they will be incorporated into the structure of plants. These plants will be eaten by animals and humans, and end up back in your body. Eventually, tiny bits of you will end up in your great grandchildren’s morning cereal or hamburger.
But there is one big exception: your body also has a tiny amount of radioactive elements. Tiny amounts of thorium and uranium will eventually become lead. But along with this decay, some atoms of helium will also be formed. Earth’s gravity isn’t strong enough to hold helium to our planet, and so tiny bits of what once was you will float off into space. So some of your atoms are in for a fantastical and exciting journey forever floating to the farthest reaches of the universe until the end of time.
You and your family can take some comfort that science says that every single vibration of every single atom of you will always be around.
