With a little thought, you can list many events and practices that are natural and yet harmful. You can also confirm that not all longstanding practices further human heath and wellbeing.
Plant food and fertilizer can be made from mined products - from rock, seawater, fresh water, and air. Various forms of these products are named.
Plants physically absorb water-soluble compounds whether they use them for their growth or not.
We eat and drink in order to obtain lipids, carbohydrates, minerals, vitamins, amino acids, water, and dietary fiber. We get the amino acids by digesting proteins. These nutrients are comprised of a number of elements, but we typically consume many additional elements that should be excluded from our diet.
All of the elements produced by stars are in the dust that falls from space through our atmosphere, onto the land, and into the sea. This has been going on since the Earth was formed 4.567 billion years ago.
Except for technetium (atomic number 43) and promethium (atomic number 61), elements up to atomic number 92 (uranium) are widely distributed. Technetium and promethium are exceedingly rare because they have no stable isotopes and quickly decay to become other elements. Elements having an atomic number greater than 92 are very rare in nature. Of the remaining 90 elements, six of them are inert gasses that exclude themselves from the chemistry of plants and animals. Of the remaining 84 elements, 28 are known to be needed by the human body, but at least 61 are found in almost every person. The number of unneeded elements that we consume outnumber the ones we need. They are responsible for many late-onset medical problems. Although the amounts of these unneeded elements are small, they do us harm. Some of these toxic elements accumulate, never leaving the body.
The list of unneeded elements found in the body is written at the end of this article.
Why not eliminate all but the essential elements?
Land plants and photosynthetic microorganisms can produce all of the nutrition that we need. To do this, they only need to be supplied with sunlight, air, and compounds that are water-soluble. Whether our diet is vegetarian or not, we cannot hope to exclude unwanted elements from our diet unless the life forms that we use for food are grown without these unwanted elements and their compounds.
Uranium is not part of any human nutrient, but you can find it in sea salt and soil - just as you can find praseodymium, cadmium, aluminum, mercury, thallium, and a great many other elements that fall to Earth. They have nothing constructive to do with the growth of your children or your good health. How could this aspect of public health be so widely ignored? I suspect that it is because it is natural. It is high time that we took dominion over the plants that we eat.
Hydroponic farming is a step in the right direction. Some hydroponic farms can exclude the unwanted elements; but some still use compost, manure, and natural soil as the basis for their plant nutrition. In the hope that gardeners and managers of farms will help further improve the quality of our food, this article offers a list of non-toxic sources of plant nutrients.
The table below includes the atomic number and chemical symbol of each food element. Arsenic (which is needed in very small amounts) can be omitted from the list of elements intentionally fed to plants because it is already in the human environment at a toxic level, so the number of elements that should be fed to plants is 27. Note that many compounds listed are comprised of several needed elements; therefore, the number of mined substances that might be used to make hydroponic plant food or fertilizer is considerably less than 27.
1 - H - Hydrogen - Water (H2O)
3 - Li - Lithium - lithium carbonate (Li2CO3), lithium chloride (LiCl), lithium chloride monohydrate (LiCl·H2O), lithium perchlorate (LiClO4), lithium perchlorate trihydrate (LiClO4·3H2O), lithium iodide (LiI), lithium iodide trihydrate: (LiI·3H2O), lithium hydroxide (LiOH), lithium hydroxide monohydrate: (LiOH·H2O), lithium sulfate (Li2SO4), lithium sulfate monohydrate (Li2SO4·H2O), lithium sulfide (Li2S)
5 - B - Boron - sodium borate (Na2B4O7·10H2O), boric acid (H3BO3), anhydrous borax (Na2B4O7), borax pentahydrate (Na2B4O7·5H2O), borax decahydrate (Na2B4O7·10H2O), calcium borate (Ca3(BO3)2)
6 - C - Carbon - carbon dioxide (CO2)
7 - N - Nitrogen - ammonia (NH3), ammonium phosphate ((NH4)3PO4), urea (CO(NH2)2), ammonium sulfate ((NH4)2SO4).
The ultimate source of nitrogen is N2 in the atmosphere. Some microorganisms on land and in lakes and oceans can fix atmospheric nitrogen
to make nitrogen-bearing minerals available to other life forms.
8 - O - Oxygen - water (H2O), carbon dioxide (CO2)
11 - Na - Sodium - sodium chloride (NaCl), sodium silicate (Na2SiO3), sodium sulfate (Na2SO4), sodium decahydrate (Na2SO4·10H2O), sodium phosphate (Na3PO4),
12 - Mg - Magnesium - magnesium chloride (MgCl2), magnesium sulfate (MgSO4), epsom salt = epsomite (MgSO4·7H2O)
14 - Si - Silicon - silicic acid = orthosilicic acid (Si(OH)4), metasilicic acid (H2SiO3),
disilicic acid (H2Si2O5),
pyrosilicic acid (H6Si2O7)
These have been identified only in very dilute aqueous solution.
See this article, and this article.
15 - P - Phosphorus - ammonium phosphate ((NH4)3PO4), sodium phosphate (Na3PO4), potassium phosphate (K3PO4), urea phosphate (CO(NH2)2·H3PO4).
16 - S - Sulfur - ferrous sulfate (FeSO4), potassium sulfate (K2SO4), potassium magnesium sulfate (K2SO4·2MgSO4), langbeinite (K2Mg2(SO4)3), zinc sulfate (ZnSO4), zinc sulfate heptahydrate (ZnSO4·7H2O), manganese sulfate (MnSO4), manganese sulfate hydrate, cupric sulphate (CuSO4), cobalt(II) sulfate (CoSO4), nickel sulfate (NiSO4), nickel sulfate hexahydrate (NiSO4·6H2O), sodium sulfate (Na2SO4), sodium decahydrate (Na2SO4·10H2O), tin(II) sulfate (SnSO4), vanadyl(IV) sulfate, (VOSO4), ammonium sulfate ((NH4)2SO4).
17 - Cl - Chlorine - sodium chloride (NaCl)
19 - K - Potassium - potassium carbonate (K2CO3), potassium chloride (KCl), potassium sulfate (K2SO4), potassium magnesium sulfate (K2SO4·2MgSO4), langbeinite (K2Mg2(SO4)3), caustic potash or potash lye or potassium hydroxide (KOH), potassium chlorate (KClO3), potassium nitrate (KNO3), potassium permanganate (KMnO4), potassium phosphate (K3PO4)
20 - Ca - Calcium - calcium chloride (CaCl2),
23 - V - Vanadium - vanadium pentoxide (V2O5), vanadium chloride (VCl3), vanadyl(IV) sulfate, (VOSO4)
24 - Cr - Chromium - chromium chloride (CrCl2)
25 - Mn - Manganese - manganese sulfate (MnSO4), manganese sulfate hydrate (MnSO4·xH2O), manganese(II) chloride (MnCl2), manganese(II) chloride (MnCl2·H2O), manganese(II) chloride (MnCl2·2H2O), manganese(II) chloride (MnCl2·4H2O)
26 - Fe - Iron - ferric chloride (FeCl3), ferrous sulfate (FeSO4)
27 - Co - Cobalt - cobalt (II) chloride (CoCl2), cobalt(II) nitrate (Co(NO3)2), cobalt(II) sulfate (CoSO4)
28 - Ni - Nickel - nickel(II) chloride = nickel chloride (NiCl2), nickel chloride hydrate NiCl2·6H2O, nickel sulfate (NiSO4), nickel sulfate hexahydrate (NiSO4·6H2O)
29 - Cu - Copper - copper chloride (CuCl2), cupric sulfate (CuSO4), cuprous chloride (CuCl),
30 - Zn - Zinc - zinc chloride (ZnCl2), zinc sulfate (ZnSO4), zinc sulfate heptahydrate (ZnSO4·7H2O), zinc nitrate (Zn(NO3)2), zinc nitrate hexahydrate (Zn(NO3)2·6H2O)
33 - As -Arsenic
See this site for information about arsenic.
Dietary requirements for arsenic in humans are still controversial. There are trace amounts of arsenic in almost all food and water, air and soil, so it is difficult to find humans who are isolated from all sources of arsenic. There are no known human health effects of arsenic deficiency, if such exist, and the effects observed in arsenic-deficient animals would be hard to detect and characterize in humans. Most investigators believe that it is likely that we receive all the arsenic we need from a normal diet, and there is currently no recommendation for a daily dietary intake for humans.
Here are forms of Arsenic that have been found in drinking water:
Arsenous acid (arsenite), As(OH)3
Arsenic acid (arsenate), AsO(OH)3
Monomethylarsonic acid, CH3AsO(OH)2
Monomethylarsonous acid, CH3As(OH)2
Dimethylarsinic acid, (CH3)2AsO(OH)
Dimethylarsinous acid, (CH3)2AsOH
Trimethylarsine oxide, (CH3)3AsO
The amount of arsenic in food has been too high. At some point, when there is no arsenic in our food and when it is finally proved that a tiny amount is needed for good health, there will either need to be an arsenic choice for plant food or a dietary supplement made available.
34 - Se - Selenium - sodium selenite (Na2SeO3), selenium dioxide (SeO2), selenium trioxide (SeO3)
35 - Br - Bromine - methyl bromide (CH3Br),
42 - Mo - Molybdenum - sodium molybdate (Na2MoO4), sodium molybdate dihydrate (Na2MoO4·2H2O), potassium molybdate (K2MoO4)
50 - Sn - Tin - potassium stannate anydrous (K2SnO3), potassium stannate trihydrate (K2SnO3·3H2O), sodium stannate anhydrous (Na2SnO3), sodium stannate trihydrate (Na2SnO3·3H2O), tin(II) chloride = stannous chloride (SnCl2), tin(II) fluoride = stannous fluoride (SnF2), tin(II) sulfate (SnSO4)
53 - I - Iodine - potassium iodide (KI), sodium iodide (NaI)
There are elements needed by some life forms on Earth that should not be in our diet:
Cadmium (Cd - atomic number 48) is toxic to humans and is a major pollutant in soil, water, and air. It is excreted very much slower than it is acquired. Older people have much more cadmium in their bodies than do younger people. It has no value as a nutrient for us, but marine diatoms (a type of phytoplankton) have become dependent upon cadmium to defend against predators. All animals in the sea either eat phytoplankton or eat animals that eat phytoplankton. They cannot distinguish between the diatoms and other phytoplankton; therefore, all seafood has become a cadmium hazard after centuries of dumping it into the ocean.
Tungsten (W - atomic number 74) is in the enzymes of a few species of bacteria and archaea. According to this article, "Tungsten interferes with molybdenum and copper metabolism, and is somewhat toxic to animal life."
Acantharea, a relative large group of marine radiolarian protozoa, produce intricate mineral skeletons composed of strontium sulfate, but strontium (38 - Sr) is not an essential nutrient for the human body. Growing children use it in their bones and this leads to bone problems.
The practice of obtaining fertilizer from compost and manure must be displaced by the assembling of minerals in balanced quantities. Compost and manure contain many water-soluble compounds which are toxic, including human medications and pathogens. Plants absorb water-soluble compounds.
This is the list of unneeded elements found in the human body:
Aluminum, Antimony, Barium, Beryllium, Bismuth, Cadmium, Cerium, Cesium, Fluorine, Gallium, Germanium, Gold, Indium, Lanthanum, Lead, Mercury Niobium Radium, Rubidium, Ruthenium Samarium, Scandium, Silver, Strontium, Tantalum, Tellurium, Thallium, Thorium, Titanium, Tungsten, Uranium, Yttrium, Zirconium