State the disadvantage of using BOD values?

As much as "Standard Methods" has a reproducible procedure for BOD5 the procedure is dependent on the activities of microorganisms and they can cause variations beyond the control of the lab worker

• temperature, O2 diffusion, toxics etc can all affect the

outcome.

This is especiall true in ding round robin testing where a lab may be getting consistent results but not the same as another lab.