Micronutrient

The natural abundance of elements is dependent on their atomic number based on the process of nucleosynthesis such that elements with higher atomic numbers are typically less abundant than elements with low atomic numbers.{{Citation |last1=Prantzos |first1=Nikos |title=Stellar Nucleosynthesis |date=2011 |encyclopedia=Encyclopedia of Astrobiology |pages=1584–1592 |editor-last=Gargaud |editor-first=Muriel |url=https://link.springer.com/referenceworkentry/10.1007/978-3-642-11274-4_1084 |access-date=2025-03-17 |place=Berlin, Heidelberg |publisher=Springer |language=en |doi=10.1007/978-3-642-11274-4_1084 |isbn=978-3-642-11274-4 |last2=Ekström |first2=Sylvia |editor2-last=Amils |editor2-first=Ricardo |editor3-last=Quintanilla |editor3-first=José Cernicharo |editor4-last=Cleaves |editor4-first=Henderson James (Jim)|url-access=subscription }} Most micronutrients are trace elements with high atomic numbers, meaning they exist naturally in low concentrations. Notable exceptions to this rule are boron (atomic no. 5), manganese (atomic no. 25), and iron (atomic no. 26).

Primary producers are the main contributors to the incorporation of micronutrients into a community's chemical inventory.{{Cite book |last1=Sterner |first1=Robert Warner |title=Ecological stoichiometry: the biology of elements from molecules to the biosphere |last2=Elser |first2=James J. |date=2002 |publisher=Princeton University Press |isbn=978-0-691-07490-0 |location=Princeton}} Consumers within an ecosystem are limited to the micronutrients in the tissue of the primary producers which they eat. Primary producers obtain their micronutrients from their surrounding abiotic environment and the recycling of organic matter in soils.{{Citation |last=Rengel |first=Zed |title=Cycling of Micronutrients in Terrestrial Ecosystems |date=2007 |work=Nutrient Cycling in Terrestrial Ecosystems |series=Soil Biology |volume=10 |pages=93–121 |editor-last=Marschner |editor-first=Petra |url=https://link.springer.com/chapter/10.1007/978-3-540-68027-7_4?utm |access-date=2025-04-12 |place=Berlin, Heidelberg |publisher=Springer |language=en |doi=10.1007/978-3-540-68027-7_4 |isbn=978-3-540-68027-7 |editor2-last=Rengel |editor2-first=Zdenko|url-access=subscription }} For example, grasses take in iron from soils which animals rely upon for hemoglobin production.{{Cite journal |last1=Kobayashi |first1=Takanori |last2=Nishizawa |first2=Naoko K. |date=2012-06-02 |title=Iron Uptake, Translocation, and Regulation in Higher Plants |url=https://www.annualreviews.org/content/journals/10.1146/annurev-arplant-042811-105522 |journal=Annual Review of Plant Biology |language=en |volume=63|issue=1 |pages=131–152 |doi=10.1146/annurev-arplant-042811-105522 |pmid=22404471 |bibcode=2012AnRPB..63..131K |issn=1543-5008|url-access=subscription }}

The original source of most nutrients, including micronutrients, is the geological reservoir, also called the slow pool.{{Citation |last=Combs |first=Gerald F. |title=Geological Impacts on Nutrition |date=2013 |work=Essentials of Medical Geology: Revised Edition |pages=179–194 |editor-last=Selinus |editor-first=Olle |url=https://link.springer.com/chapter/10.1007/978-94-007-4375-5_8 |access-date=2025-03-17 |place=Dordrecht |publisher=Springer Netherlands |language=en |doi=10.1007/978-94-007-4375-5_8 |isbn=978-94-007-4375-5|url-access=subscription }} Micronutrients trapped in rocks and minerals must first be broken down through physical or chemical weathering before they can enter the fast pool, meaning they cycle between reservoirs on shorter timescales.{{Cite journal |last=Van Cappellen |first=Philippe |date=2003-01-03 |title=Biomineralization and Global Biogeochemical Cycles |url=https://pubs.geoscienceworld.org/msa/rimg/article-abstract/54/1/357/87499/Biomineralization-and-Global-Biogeochemical-Cycles |journal=Reviews in Mineralogy and Geochemistry |volume=54 |issue=1 |pages=357–381 |doi=10.2113/0540357 |bibcode=2003RvMG...54..357V |issn=1529-6466|url-access=subscription }} Micronutrients can physically exchange between reservoirs in various ways such as from terrestrial soils to oceans via aeolian transport or fluvial transport, from oceans to marine sediments via deposition of organic matter, and from sediments to the geologic reservoir via lithification. Alternatively, micronutrients can exit the geologic reservoir through tectonic processes such as through volcanism or hydrothermal vents.{{Citation |last1=Sander |first1=S. G. |title=The Export of Iron and Other Trace Metals from Hydrothermal Vents and the Impact on Their Marine Biogeochemical Cycle |date=2016 |work=Trace Metal Biogeochemistry and Ecology of Deep-Sea Hydrothermal Vent Systems |pages=9–24 |editor-last=Demina |editor-first=Liudmila L. |url=https://link.springer.com/chapter/10.1007/698_2016_4 |access-date=2025-04-19 |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/698_2016_4 |isbn=978-3-319-41340-2 |last2=Koschinsky |first2=A. |editor2-last=Galkin |editor2-first=Sergey V.|url-access=subscription }}{{Cite journal |last1=Duggen |first1=S. |last2=Olgun |first2=N. |last3=Croot |first3=P. |last4=Hoffmann |first4=L. |last5=Dietze |first5=H. |last6=Delmelle |first6=P. |last7=Teschner |first7=C. |date=2010-03-03 |title=The role of airborne volcanic ash for the surface ocean biogeochemical iron-cycle: a review |url=https://bg.copernicus.org/articles/7/827/2010/ |journal=Biogeosciences |language=English |volume=7 |issue=3 |pages=827–844 |doi=10.5194/bg-7-827-2010 |doi-access=free |bibcode=2010BGeo....7..827D |issn=1726-4170}}

Anthropogenic industry unintentionally injects micronutrients into various ecosystems across the globe. The addition of micronutrients into ecosystems can have both positive and negative impacts. In the face of climate change, the fertilization of oceans with iron has been proposed as a method of carbon sequestration;{{Cite journal |last1=Smetacek |first1=V |last2=Naqvi |first2=S.w.a |date=2008-08-29 |title=The next generation of iron fertilization experiments in the Southern Ocean |url=https://royalsocietypublishing.org/doi/abs/10.1098/rsta.2008.0144 |journal=Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences |volume=366 |issue=1882 |pages=3947–3967 |doi=10.1098/rsta.2008.0144|pmid=18757280 |bibcode=2008RSPTA.366.3947S |url-access=subscription }} however, elevated levels of iron in high nutrient, low chlorophyll regions of the ocean can cause the production of harmful algal blooms which are toxic to both humans and marine life.{{Cite journal |last1=Williamson |first1=Phillip |last2=Wallace |first2=Douglas W. R. |last3=Law |first3=Cliff S. |last4=Boyd |first4=Philip W. |last5=Collos |first5=Yves |last6=Croot |first6=Peter |last7=Denman |first7=Ken |last8=Riebesell |first8=Ulf |last9=Takeda |first9=Shigenobu |last10=Vivian |first10=Chris |date=2012-11-01 |title=Ocean fertilization for geoengineering: A review of effectiveness, environmental impacts and emerging governance |url=https://www.sciencedirect.com/science/article/abs/pii/S095758201200119X |journal=Process Safety and Environmental Protection |series=Special Issue: Negative emissions technology |volume=90 |issue=6 |pages=475–488 |doi=10.1016/j.psep.2012.10.007 |bibcode=2012PSEP...90..475W |issn=0957-5820|url-access=subscription }} Similarly, in lakes, isolated seas, and coastal bays or gulfs, addition of micronutrients can cause eutrophication leading to hypoxia, decreasing ecosystem health.{{Cite journal |last1=Deininger |first1=Anne |last2=Frigstad |first2=Helene |date=2019-04-25 |title=Reevaluating the Role of Organic Matter Sources for Coastal Eutrophication, Oligotrophication, and Ecosystem Health |journal=Frontiers in Marine Science |language=English |volume=6 |page=210 |doi=10.3389/fmars.2019.00210 |doi-access=free |bibcode=2019FrMaS...6..210D |issn=2296-7745|hdl=11250/2620750 |hdl-access=free }}

Micronutrients are released into ecosystems from many anthropogenic activities. Fossil fuel combustion releases micronutrients such as Zn, Fe, Ni, and Cu into the atmosphere, surrounding soils, and nearby waterways. Agricultural fertilizer runoff contains many micronutrients like Fe, Mn, Zn, Cu, Co, B, Mo and Ni. Fertilizer runoff injects these micronutrients into groundwater, soils, and waterways.{{Cite journal |last1=He |first1=Zhenli L. |last2=Yang |first2=Xiaoe E. |last3=Stoffella |first3=Peter J. |date=2005-12-02 |title=Trace elements in agroecosystems and impacts on the environment |url=https://www.sciencedirect.com/science/article/abs/pii/S0946672X05000969 |journal=Journal of Trace Elements in Medicine and Biology |volume=19 |issue=2 |pages=125–140 |doi=10.1016/j.jtemb.2005.02.010 |bibcode=2005JTEMB..19..125H |issn=0946-672X|url-access=subscription }} Deforestation decreases soil compaction, resulting in increased aeolian transport of dust containing micronutrients, especially Fe. Industrial mining produces tailings which contaminates runoff. The improper treatment of mining tailings can result in the leakage of micronutrients into groundwater, soils, and nearby waterways.{{Cite journal |last1=Qiao |first1=Pengwei |last2=Wang |first2=Shuo |last3=Li |first3=Jiabin |last4=Zhao |first4=Qianyun |last5=Wei |first5=Yan |last6=Lei |first6=Mei |last7=Yang |first7=Jun |last8=Zhang |first8=Zhongguo |date=2023-01-20 |title=Process, influencing factors, and simulation of the lateral transport of heavy metals in surface runoff in a mining area driven by rainfall: A review |url=https://www.sciencedirect.com/science/article/abs/pii/S0048969722062180 |journal=Science of the Total Environment |volume=857 |issue=Pt 1 |pages=159119 |doi=10.1016/j.scitotenv.2022.159119 |pmid=36183764 |bibcode=2023ScTEn.85759119Q |issn=0048-9697|url-access=subscription }}

Inadequate intake of essential nutrients predisposes humans to various chronic diseases, with some 50% of American adults having one or more preventable disease. In the United States, foods poor in micronutrient content and high in food energy make up some 27% of daily calorie intake. One US national survey (National Health and Nutrition Examination Survey 2003-2006) found that persons with high sugar intake consumed fewer micronutrients, especially vitamins A, C, and E, and magnesium. Various strategies have been employed to combat micronutrient deficiencies:

Salt iodization is a strategy for addressing iodine deficiency, which is a cause of mental health problems.{{Cite journal |last1=Redman |first1=Kahla |last2=Ruffman |first2=Ted |last3=Fitzgerald |first3=Penelope |last4=Skeaff |first4=Sheila |date=2016-12-09 |title=Iodine Deficiency and the Brain: Effects and Mechanisms|pmid=25880137 |url=https://www.tandfonline.com/doi/pdf/10.1080/10408398.2014.922042 |journal=Critical Reviews in Food Science and Nutrition|volume=56|issue=16|pages=2695–2713 |doi=10.1080/10408398.2014.922042 |issn=1040-8398|url-access=subscription }} In 1990, less than 20 percent of households in developing countries had adequate iodine in their diet.Flour Fortification Initiative, GAIN, Micronutrient Initiative, USAID, The World Bank, UNICEF, Investing in the future: a united call to action on vitamin and mineral deficiencies, p. 19. By 1994, international partnerships had formed in a global campaign for Universal Salt Iodization. By 2008, it was estimated that 72 percent of households in developing countries included iodized salt in their diets,UNICEF, The State of the World's Children 2010, Statistical Tables, p. 15. and the number of countries in which iodine deficiency disorders were a public health concern reduced by more than half from 110 to 47 countries.

Vitamin A deficiency is a major factor in causing blindness worldwide, particularly among children. Global vitamin A supplementation efforts have targeted 103 priority countries. Flour fortification has become an increasingly common method by which vitamin A can be added to diets thus reducing deficiencies. {{Cite journal |last1=Klemm |first1=Rolf D. W. |last2=WestJr. |first2=Keith P. |last3=Palmer |first3=Amanda C. |last4=Johnson |first4=Quentin |last5=Randall |first5=Philip |last6=Ranum |first6=Peter |last7=Northrop-Clewes |first7=Christine |date=2010-03-01 |title=Vitamin A Fortification of Wheat Flour: Considerations and Current Recommendations |url=https://journals.sagepub.com/doi/abs/10.1177/15648265100311S105 |journal=Food and Nutrition Bulletin |language=EN |volume=31 |issue=1_suppl1 |pages=S47–S61 |doi=10.1177/15648265100311S105 |pmid=20629352 |issn=0379-5721|url-access=subscription }}

Zinc is a necessary micronutrient which the human body uses to fight infections and childhood diarrhea. Collectively, zinc deficiencies are responsible for 4% of child morbidity and mortality, as of 2013.{{Cite journal |last=Penny |first=Mary Edith |date=2013-05-03 |title=Zinc Supplementation in Public Health |url=https://karger.com/anm/article-abstract/62/Suppl.%201/31/433/Zinc-Supplementation-in-Public-Health?redirectedFrom=fulltext |journal=Annals of Nutrition and Metabolism |volume=62 |issue=Suppl. 1 |pages=31–42 |doi=10.1159/000348263 |issn=0250-6807|url-access=subscription }} Fortification of staple foods such as breads may improve serum zinc levels in the human population, increasing immune strength.{{cite journal |vauthors=Shah D, Sachdev HS, Gera T, De-Regil LM, Peña-Rosas JP |date=June 2016 |title=Fortification of staple foods with zinc for improving zinc status and other health outcomes in the general population |journal=Cochrane Database Syst Rev |volume=2016 |issue=6 |pages=CD010697 |doi=10.1002/14651858.CD010697.pub2 |pmc=8627255 |pmid=27281654}} Zinc fortification has also been considered for reducing effects cognition, though the effectiveness is still under research.

{{Main|Plant nutrition}}

Plants rely on micronutrients to build many essential proteins. In fact, every process that supports the growth of a plant is mediated by some protein which contains one of the many micronutrients.{{Cite journal |last1=Hänsch |first1=Robert |last2=Mendel |first2=Ralf R |date=2009-06-01 |title=Physiological functions of mineral micronutrients (Cu, Zn, Mn, Fe, Ni, Mo, B, Cl) |url=https://www.sciencedirect.com/science/article/abs/pii/S1369526609000429 |journal=Current Opinion in Plant Biology |series=Physiology and Metabolism |volume=12 |issue=3 |pages=259–266 |doi=10.1016/j.pbi.2009.05.006 |pmid=19524482 |bibcode=2009COPB...12..259H |issn=1369-5266|url-access=subscription }} For example, Mn is an essential micronutrient for many plants because it builds the structure of photosystem II which splits water molecules to harness energy from electrons.{{Cite journal |last1=Mukhopadhyay |first1=Sumitra |last2=Mandal |first2=Sanjay K. |last3=Bhaduri |first3=Sumit |last4=Armstrong |first4=William H. |date=2004-09-01 |title=Manganese Clusters with Relevance to Photosystem II |url=https://pubs.acs.org/doi/full/10.1021/cr0206014 |journal=Chemical Reviews |volume=104 |issue=9 |pages=3981–4026 |doi=10.1021/cr0206014 |pmid=15352784 |issn=0009-2665|url-access=subscription }} Inadequate micronutrient uptake can result in deficiencies and even mortality in extreme cases.{{Citation |last=Langridge |first=Peter |title=Micronutrient Toxicity and Deficiency |date=2022 |work=Wheat Improvement: Food Security in a Changing Climate |pages=433–449 |editor-last=Reynolds |editor-first=Matthew P. |url=https://link.springer.com/chapter/10.1007/978-3-030-90673-3_24 |access-date=2025-04-14 |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-030-90673-3_24 |isbn=978-3-030-90673-3 |editor2-last=Braun |editor2-first=Hans-Joachim|url-access=subscription }} Alternatively, elevated concentrations of micronutrients in soils can result in toxicity.

Examples of Plant Micronutrient Deficiencies

• Chlorosis, a condition where a plant cannot produce sufficient chlorophyll. A lack in copper, iron, manganese, or zinc can cause chlorosis.{{Cite journal |last1=Therby-Vale |first1=Rebecca |last2=Lacombe |first2=Benoit |last3=Rhee |first3=Seung Y. |last4=Nussaume |first4=Laurent |last5=Rouached |first5=Hatem |date=2022-05-01 |title=Mineral nutrient signaling controls photosynthesis: focus on iron deficiency-induced chlorosis |url=https://www.cell.com/trends/plant-science/abstract/S1360-1385(21)00311-3 |journal=Trends in Plant Science |language=English |volume=27 |issue=5 |pages=502–509 |doi=10.1016/j.tplants.2021.11.005 |issn=1360-1385 |pmid=34848140|bibcode=2022TPS....27..502T }}
• Boron deficiency, a condition where a plant's ability to reproduce, grow, and create stem cells is inhibited.{{Cite journal |last1=Lehto |first1=Tarja |last2=Ruuhola |first2=Teija |last3=Dell |first3=Bernard |date=2010-12-15 |title=Boron in forest trees and forest ecosystems |url=https://www.sciencedirect.com/science/article/abs/pii/S0378112710005608 |journal=Forest Ecology and Management |volume=260 |issue=12 |pages=2053–2069 |doi=10.1016/j.foreco.2010.09.028 |bibcode=2010ForEM.260.2053L |issn=0378-1127|url-access=subscription }}
• Molybdenum deficiency, a condition where a buildup in nitrate because of a lack of nitrogenase production causes leaf yellowing, necrosis, and premature germination.{{Cite book |last1=Mengel |first1=Konrad |title=Principles of plant nutrition |last2=Kirkby |first2=Ernest A. |last3=Kosegarten |first3=Harald |date=2001 |publisher=Kluwer Academic Publishers |isbn=978-0-7923-7150-2 |edition=5 |location=Dordrecht}}

{{Portal|Ecology}}

• List of micronutrients
• Human nutrition
• Dietary mineral (redirects to Mineral (nutrient))
• Silicon § Human nutrition
• Manganese deficiency (medicine)

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Category:Nutrition