Microbial DNA contamination in reagent

Which reagents can bear contamination by microbial DNA?

In principle, all!

In particular, in our experience, the Taq DNA polymerase and primers are mostly prone to DNA contamination due to the manufacturing processes.
Molzym has invested great efforts to develop a purification process for the elimination of microbial DNA from PCR reagentsguaranteed for 40 cycles.