Phosphorus Atom

• The atomic radius of Phosphorus atom is 107pm (covalent radius). It must be noted, atoms lack a well-defined outer boundary. The atomic radius of a chemical element is a measure of the distance out to which the electron cloud extends from the nucleus.
• About Phosphorus. Like its close chemical relative, nitrogen, phosphorus is a nonmetallic element with a seemingly contradictory nature.Found in fundamental organic compounds such as DNA, ATP, and phospholipids, phosphorus is essential to life, yet it is also a component of dangerous explosives and some of the most potent poisons known, organophosphate nerve agents.

What is phosphorus?

Phosphorus is a mineral found in your bones. Along with calcium, phosphorus is needed to build strong healthy bones, as well as, keeping other parts of your body healthy.

Why is phosphorus important to you?

Black phosphorus has an orthorhombic pleated honeycomb structure and is the least reactive allotrope, a result of its lattice of interlinked six-membered rings where each atom is bonded to three other atoms. Black and red phosphorus can also take a cubic crystal lattice structure.

Normal working kidneys can remove extra phosphorus in your blood. When you have chronic kidney disease (CKD), your kidneys cannot remove phosphorus very well. High phosphorus levels can cause damage to your body. Extra phosphorus causes body changes that pull calcium out of your bones, making them weak. High phosphorus and calcium levels also lead to dangerous calcium deposits in blood vessels, lungs, eyes, and heart. Over time this can lead to increased risk of heart attack, stroke or death. Phosphorus and calcium control are very important for your overall health.

What is a safe blood level of phosphorus?

A normal phosphorus level is 2.5 to 4.5 mg/dL. Ask your kidney doctor or dietitian what your last phosphorus level was and write it down to help keep track of it.

Will dialysis help with phosphorus control?

Yes. Dialysis can remove some phosphorus from your blood. It is important for you to understand how to limit build-up of phosphorus between your dialysis treatments.

How can I control my phosphorus level?

You can keep you phosphorus level normal by understanding your diet and medications for phosphorus control. Phosphorus can be found in foods (organic phosphorus) and is naturally found in protein-rich foods such as meats, poultry, fish, nuts, beans and dairy products. Phosphorus found in animal foods is absorbed more easily than phosphorus found in plant foods.

Phosphorus that has been added to food in the form of an additive or preservative (inorganic phosphorus) is found in foods such as fast foods, ready to eat foods, canned and bottled drinks, enhanced meats, and most processed foods. Phosphorus from food additives is completely absorbed. Avoiding phosphorus additives can lower your intake of phosphorus. Phosphorus additives are found on the list of ingredients on the nutrition facts label. Look for “PHOS” to find phosphorus additives in the food.

Phosphorus additives found in foods include:

• Dicalcium phosphate
• Disodium phosphate
• Monosodium phosphate
• Phosphoric acid
• Sodium hexameta-phosphate
• Trisodium phosphate
• Sodium tripolyphosphate
• Tetrasodium pyrophosphate

Your kidney dietitian and doctor will help you with this. Below is a list of foods high in phosphorous and lower phosphorus alternatives to enjoy:

HIGH PHOSPHORUS FOOD TO LIMIT OR AVOID

Looking for nutrition guidance? Contact a CKD dietitian in your area.

What medications are for phosphorus control?

Your kidney doctor may order a medicine called a phosphate binder for you to take with meals and snacks. This medicine will help control the amount of phosphorus your body absorbs from the foods you eat.

There are many different kinds of phosphate binders. Pills, chewable tablets, powders, and liquids are available. Some types also contain calcium, while others do not. You should only take the phosphate binder that is ordered by your doctor or dietitian.

Read more about Phosphorus and Your CKD Diet.

Acknowledgment: Reviewed by the Council on Renal Nutrition (04/2019)

Phosphorus is a chemical element found on Earth in numerous compound forms, such as the phosphate ion (PO₄^3-), located in water, soil and sediments. The quantities of phosphorus in soil are generally small, and this often limits plant growth. That is why people often apply phosphate fertilisers on farmland. Animals absorb phosphates by eating plants or plant-eating animals.

The role of phosphorus in animals and plants

Phosphorus is an essential nutrient for animals and plants. It plays a critical role in cell development and is a key component of molecules that store energy, such as ATP (adenosine triphosphate), DNA and lipids (fats and oils). Insufficient phosphorus in the soil can result in a decreased crop yield.

The phosphorus cycle

Phosphorus moves in a cycle through rocks, water, soil and sediments and organisms.

Here are the key steps of the phosphorus cycle

• Over time, rain and weathering cause rocks to release phosphate ions and other minerals. This inorganic phosphate is then distributed in soils and water.
• Plants take up inorganic phosphate from the soil. The plants may then be consumed by animals. Once in the plant or animal, the phosphate is incorporated into organic molecules such as DNA. When the plant or animal dies, it decays, and the organic phosphate is returned to the soil.
• Within the soil, organic forms of phosphate can be made available to plants by bacteria that break down organic matter to inorganic forms of phosphorus. This process is known as mineralisation.
• Phosphorus in soil can end up in waterways and eventually oceans. Once there, it can be incorporated into sediments over time.

Most phosphorus is unavailable to plants

Since most of our phosphorus is locked up in sediments and rocks, it’s not available for plants to use. A lot of the phosphorus in soils is also not available to plants.

The availability of phosphorus in soil to plants depends of several reversible pathways:

• Bacteria: Bacteria convert plant-available phosphate into organic forms that are then not available to plants. Although other bacteria make phosphate available by mineralisation, the contribution of this is small.
• Adsorption: Inorganic (and available) phosphorus can be chemically bound (adsorbed) to soil particles, making it unavailable to plants. Desorption is the release of adsorbed phosphorus from its bound state into soil solution.
• pH: Inorganic phosphorus compounds need to be soluble to be taken up by plants. This depends on the acidity (pH) of the soil. If soils are less than pH 4 or greater than pH 8, the phosphorus starts to become tied up with other compounds, making it less available to plants.

Many plant crops need more phosphorus than is dissolved in the soil to grow optimally. In addition, crops are usually harvested and removed – leaving no decaying vegetation to replace phosphorus. Therefore, farmers replenish the phosphorus ‘pool’ by adding fertilisers or effluent to replace the phosphorus taken up by plants.

Phosphate fertilisers replenish soil phosphorus

Many farmers replenish phosphorus through the use of phosphate fertilisers. The phosphorus is obtained by mining deposits of rock phosphate. Locally produced sulfuric acid is used to convert the insoluble rock phosphate into a more soluble and usable form – a fertiliser product called superphosphate.

In New Zealand, superphosphate is made using rock imported mainly from Morocco.

Phosphorus Atom Valence Electrons

Adjusting the pH of the soil for efficient plant uptake of phosphate should be done prior to fertilisation. For example, adding lime reduces soil acidity, which provides an environment where phosphate becomes more available to plants.

Water pollution by fertilisers

When fields are overfertilised (through commercial fertilisers or manure), phosphate not utilised by plants can be lost from the soil through leaching and water run-off. This phosphate ends up in waterways, lakes and estuaries. Excess phosphate causes excessive growth of plants in waterways, lakes and estuaries leading to eutrophication.

Steps are being taken in agriculture to reduce phosphate losses in order to maximise the efficiency of fertiliser and effluent applications.

Nature of science

Facts About Phosphorus

Scientists make observations and develop their explanations using inference, imagination and creativity. Often they use models to help other scientists understand their theories. The phosphorus cycle diagram is an example of an explanatory model. Diagrams demonstrate the creativity required by scientists to use their observations to develop models and to communicate their explanations to others.

Phosphorus Atomic Wt