[The effect of tannery waste products on viability of selected bacteria from activated sludge].

In this study we have investigated the influence of sludge on the activity of bacteria strains: Acinetobacter baumannii, Aeromonas hydrophila and Pseudomonas cepacia. To our studies we have taken waste materials used in the chromium compound leather tanning process as well as materials from leather fat and waste materials, in general. It was confirmed that 1:20 dilution of chromium tanning leather waste, retanage and leather fat allowed the survivability of bacteria in all three strains. Through our research we were able to establish that general sewage with a decreased level of chromium practically did not effect the survivability of bacteria in a sewage environment. Both types of waste, city sewage as well as leather waste, were shown not to facilitate bacterial growth. If chromium waste flow into city sewage without treatment, bacteria can only survive at a dilution level of 1:20, which will not affect the survivability of bacteria used in biological waste treatment.