Question #13: Natural vs. Manmade/Man produced Chemicals

This is a question that I am often asked and even more often hear others talking about. However, it is a misnomer from the scientific perspective. Before we get into the topic itself I think it is important to discuss scientific naming.

Lets talk about oranges.

The common store Naval or Sweet Orange is from the tree Citrus x sinensis. That is the genus and species name of the citrus tree that produces oranges. However, there are other citrus fruit but we would never call them oranges and the other fruits come from trees with different scientific names. The scientific name identifies the type of tree and its fruit.

Now, lets imagine two orange trees. One is growing in the forest of Southeast Asia where the orange tree likely evolved and the other is on a farm in Florida. We might say that the tree in Asia is growing naturally and that the one in Florida is being produced (farmed) by man. Does this mean that the oranges are any different if we know both trees are Citrus x sinensis? Nope, in fact, now that we know that the trees are the same species we know that the oranges are both the same too. This is how scientific names work. They identify a specific item so that when people discuss the item that everyone knows exactly what the subject is.

What about chemicals?

Lets talk about a chemical that people often talk about Formaldehyde. Formaldehyde has the chemical formula CH₂O and looks like the picture below when drawn.

Formaldehyde is the name that only identifies a chemical with that chemical formula and the atoms arranged in the way it is shown in the picture.

Natural vs Manmade Formaldehyde.
Formaldehyde occurs naturally in our bodies (and the bodies of other plants and animals) as a byproduct of the reactions that produce DNA, RNA and proteins. We could say this is naturally occurring or natural formaldehyde. It also occurs in the atmosphere and in outerspace. (known as Interstellar Formaldehyde)

Manmade formaldehyde is produced with a combination of metals (iron or silver often) and methanol (wood alcohol). This is known as the Formox process.

So, what is the difference between the manmade and naturally occurring formaldehyde? Nothing. As the name formaldehyde identifies the chemical with a unique chemical formula and way the atoms are arranged the process used to produce it has no effect on how the formaldehyde will react. Both, made in our body and processed in a plant, have the same chemical properties, the same LD50 (i.e. level of toxicity), and reactivity.

The same can be said for any chemical. To have the name the chemical must be the same. (an orange is an orange if it has the same species name) Other examples would be carbon dioxide produced when we exhale and carbon dioxide produced by burning fossil fuels.

Other considerations or what really matters?
When it comes to chemicals concentration, not where it was produced, is what is important.  High concentrations of chemicals can happen naturally, consider the salt content of the dead sea. High concentrations can happen from the activities of man, consider the salt destruction of soils through irrigation practices. Both of these are detrimental to growing plants though one is a natural occurrence. We can also have beneficial concentrations of sodium, for example, we need sodium chloride to move our muscles and pass electrical current through our neurons. In all cases the salt, sodium chloride or NaCl, has the same arrangement of atoms and is the same substance. In truth, all chemical substances, including water, have a point where they are safe and where they are dangerous. Though there doesn't seem to be a complete list of LD50s, the amount required to have a 50% chance of death, there is a place that will calculate and has a list of some common chemicals here.