Table 1. The possible maximum concentration of non-ionized nitrite as a function of the pH and initial nitrate concentration, assuming that nitrate is completely converted to nitrite and the latter accumulates.

pH

  Maximal HNO₂concentration [mg N-HNO₂ L^-1] at an 
initial nitrate concentration of: 

80 [mg NO₃^--N L^-1]

10 [mg NO₃^--N L^-1]

6.5

0.0420

0.0040

7.0

0.0133

0.0017

7.5

0.0042

0.0005

8.0

0.0013

0.0002

8.5

0.0004

0.0001

9.0

0.00013

0.00002