Skip to main content

Vocabulary Term Details

Phosphate phosphorus



Preferred Units: milligrams per litre

Scope Note:
Most labs report Phosphorus as phosphate -- sometimes abbreviated PO4-P. So a result of (say) 10 mg/L of phosphate (PO4 3-), would be reported as 3.2 mg/L PO4-P. Both the lab and the data user have to crystal clear on how the number is reported. [That calculation is as follows: atomic weight of phosphorus is 31, oxygen is 16. So PO4 is (31 + (4 x 16) = 91. The phosphorus is therefore 31/95 as a fraction of the phosphate anion: so 10 mg/L phosphate = 10 x (31/95) = 3.2 mg/L PO4-P.]

Broader TermsNarrower TermsRelated Terms
Water quality measurements

This term is used for the following terms: 
Phosphorus measured as phosphate

Approved Date

Items having a keyword or observed-property relationship to this subject term

Click here to give feedback on this term or suggest an update.