Nitrates, Phosphates, Hardness

Brooke D, Aaron S, Caroline H


What are these contaminants: nitrates, phosphates, and hardness?

Nitrate: Salt or ester of nitric acid, containing the anion NO3 or the group -NO3
https://www.google.com/#q=definition+of+nitrate&spell=1

Phosphate: Salt or ester of phosphoric acid, containing PO43- or a related anion or a group such as -OPO()H)2
https://www.google.com/#q=definition+of+phosphate

Hardness: Water that has high mineral content (in contrast with soft water). Hard water minerals primarily consist of calcium (ca2+) and magnesium (Mg2+) metal cautions, and sometimes other dissolved compounds such as bicarbonates and sulfates.
https://www.google.com/#q=definition+of+hardness+of+water

How do they hurt us?

Nitrates:

• can cause methemoglobinemia
• causes an increase in bacteria that can readily convert nitrate to nitrite (NO₂)
• methemoglobinemia can result in brain damage and death

http://www.ext.colostate.edu/pubs/crops/00517.html

Phosphates:

• too much exposure to phosphate can cause kidney damage and osteoporosis
•  phosphorus is the most dangerous: extremely poisonous and can be fatal

http://www.lenntech.com/periodic/elements/p.htmhite

Hardness:

• Hardness in water has little health risk, but instead has been found to reduce the risk of cardiovascular disease in those who drink hard water throughout their lives.
• However hardness in water has negative effects on appliances and clothing

How do they get in our water?

Nitrates enter our water sources through fertilizer use, leaking from septic tanks, sewage, and erosion of natural deposits.

http://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm

Phosphates enter our water sources through waste by animals and humans, bed rock rich in phosphorous, laundry, cleaning, and fertilizer runoff.

http://www.water-research.net/Watershed/phosphates.htm

Hardness enters our water sources by water acts as a solvent and dissolves the minerals in the soil and rock in the water which creates the hardness in the water

http://www.watersystemscouncil.org/VAiWebDocs/WSCDocs/1683274HARDNESS.PDF

How do we get rid of them?

The removal of calcium and magnesium from water would cause the hardness in water to become softness. The two most common processes to do this are called reverse osmosis filtration and ion exchange. Reverse osmosis filtration is process in which feed water flows along the membrane surface under pressure.

http://www.glendalewaterandpower.com/residents/water_hardness.aspx

http://www.appliedmembranes.com/Reverse_Osmosis_Systems.htm