Cutting fluid high on nitrite

Hello! I've noticed our cutting fluid doing weird stuff like bad oily smell and coloring everything in dark yellow almost brown from several weeks. We changed the fluid this year to Mobilcut 250-new, at start it had some odor like bad perfume but it disappeared after 1 month of use. My boss tried to call someone to come see and test if possible but no one takes responsibility...so...here i am trying to do and learn something :D i've ordered a refractometer cause we never used one to check and i'm 99% sure the fluid is highly concentrated from topping the tanks. For now i just checked with some test stripes i had laying around (picture below)

Attachment 448087

First stripe is clean fluid with 5% concentrate Mobilcut 250-new
Second stripe is from the Lathe's tank

The thing that bothers me is the Nitrite part! Isn't it too high ? Comparing to the bottle it is above 80mg, way darker color than the scale for 80mg. Isn't Nitrite cancerogenic ? What should i do ?

Is someone maintaining their fluids weekly or am i just freaking out cause of some cancer words :confused: