Sulfide

Sulfide

Sulfide is often present in groundwater and sediment and is sometimes found in industrial or municipal wastewater. Sulfide is produced by the decomposition of organic matter and reduction of sulfate by bacteria. One form of sulfide is gaseous hydrogen sulfide (H2S) which is very toxic to humans. The dissolved H2S is also toxic to fish and other aquatic organisms. Hydrogen sulfide can escape into the air from sulfide-containing wastewater causing nuisance orders. The odor threshold odor concentration of H2S in clean water is between 0.025 and 0.25 μg/L. Hydrogen sulfide also attacks metals directly and indirectly causes the corrosion of concrete sewers. Hydrogen sulfide combines with iron and other metals, in natural sediments and sludges, to form slightly soluble acid-volatile sulfide (AVS). The determination of AVS concentrations has become more prevalent because it plays a key part in controlling the bioavailability of toxic metals in anoxic sediments. Hanna Instruments offers a wide variety of instrumentation for measuring sulfide. Products include portable and benchtop pH/ISE meters that can use a solid-state sulfide Ion-Selective Electrode (ISE) for direct measurement.