Toxic effect assessment of aminotetrazoles and high-energetic azotetrazole salts on soil microbial respiration

Abstract

The influence of energetic heterocyclic high-nitrogen salts on microbial activity in soil enrichment was investigated. 5-Aminotetrazole, a sodium salt of 5-aminotetrazole, ammonium azotetrazolate, sodium azotetrazolate, guanidinium azotetrazolate, triaminoguanidine azotetrazolate and triaminoguanidine hydrochloride were examined. Respiration tests determined the amount and rate of production of CO2, H2 and H2S from microbial activity. Aminotetrazoles, triaminoguanidine azotetrazolate and triaminoguanidine hydrochloride substantially reduced the amount and rate of microbial CO2 production. The total amount of CO2 produced in the soil enrichments was affected by the cation from the azotetrazole salt, whereas the azotetrazolate anion did not seem to inhibit microbial CO2 production. In contrast, all applied compounds stopped the production of H2S completely and modified the rate of H2 production in the cultures compared with the control. The influence of ammonium azotetrazolate and sodium azotetrazolate on the activity of isolated sulfate-reducing bacteria was also determined. The compounds did not have bactericidal activity towards sulfate-reducing bacteria, but the compounds decreased the amount of H2S produced or slowed the growth of these bacteria in comparison with the control.