The levels of H2S gas recorded for each digester is also indicative of the quality of the biogas produced from all the substrates under study. It showed that in all the digesters the H2S was between 1.00 - 3.14% of the total biogas produced. The only exception was in paper waste digester where the record indicated a higher percentage of the H2S gas (3.14%). This may be attributable to the presence of additive sulphite especially inorganic sulphites introduced during the process of paper making especially during the pulping process. The absorption of H2S was possible because of the reaction between H2S and Lead ethanoate that led to the formation of the precipitate. The equation for the reaction is given as;