MACO and NOEL calculations have great importance in the pharmaceutical industries. NOEL( No observed effect level) and MACO is a (Maximum allowable carry over). NOEL is used to determine MACO during cleaning validation.
NEOL is calculated by using LD50 and avg. Adult dose.
NEOL= LD50 x Avg. adult dose/ 2000
LD50 is a lethal dose (it may vary) if adult avg. Weight is 70kg, and 2000 is content. For example, if an LD50 of any drug product is 250mg/kg. then NOEL calculation is
NEOL= 250×70/2000= 8.75mg.
Related Post: Cleaning Method Validation
from the NEOL equation, MACO can be calculated according to the formula:
MACO= NOELxMBS/ SFxTDD
Whereas NOEL is No observed effect level
MBS is the Minimum batch size for the next product
SF is the Safety factor.
TDD is the largest normal daily dose for the product
For example: if the total daily dose of a product is 350mg and their batch size is 100 kg, our NOEL is 8.75 mg. then MACO can be calculated as follow:
MACO= 8.75(mg)x100000000/1000×350(mg)= 250mg
or 0.25 gm.
What NOEL and MACO prove:
From this, we can find out the quantity of a drug that can not be carried out over to the next batch. As studies above for 250mg /kg LD50 should not be over to 0.25gm in the next batch as per above the batch having 350mg daily dose and 100 kg batch size.
Scope of MACO in pharmaceuticals:
MACO and NOEL Calculation are widely used for determining acceptance criteria, cleaning levels, Determination of the amount of residue present, and cleaning validation protocol.