[Usefulness of various enzyme tests in the evaluation of the effects of chronic exposure to manganese and iron].

In those chronically exposed to manganese the activity of alanine aminotransferase (ALAT), asparagine aminotransferase (AspAT), lactate dehydrogenase (LDH), cholinesterase (ChE) and ceruloplasmin (CPL) was determined. As compared with the control group, only enzymatic activity was statistically decreased. Thus, determination of the mentioned enzymes in blood serum is of little value for evaluation of an early stage of manganese toxic effects.