Hydrogen Sulphide (H2S)

Hydrogen sulfide (H2S) is a colourless gas with a characteristic odour of rotten eggs which being denser than air may pool in low areas in still conditions.

people are normally exposed to hydrogen sulphide in air by breathing it in or by skin/eye contact. Any absorbed hydrogen sulphide does not accumulate in the body as it is rapidly metabolised in the liver and excreted in the urine. Hydrogen sulphide usually breaks down in air in about 3 days and is dispersed by wind.

If the smell of hydrogen sulphide is strong or you are concerned about its impacts on your amenity or health, you can reduce exposure by:

• avoiding areas that are known sources of hydrogen sulphide
• keeping windows closed when the odour outdoors is noticable and opening doors and windows once the outdoor odour has subsided
• not excersising outdoors when the smell is present, particulalry if your breathing rate increases

If the sulphide is being generated by human activities then apporpriate management of those activities may help adress the problem at source. For instance industrial emissions might be dealt with through process or engineering controls such as contrainment or filter ventilation.

When bore water is contaminated with hydrogen sulphide it is sometimes possible to treat the bore with an agent wich removes iron from the water and therefore interferes with bacterial activity which happens to generate the gas.

Water treatment companies can advise on suitable agents.

Use of hydrogen sulphide impacted water for irrigation purposes has the potential to release considerable amounts of gas, as mentioned above. Methods for reducing odour impacts include the following:

• decreasing the quantity of water used
• using drippers or delivery devices which are low to the ground and have large droplet size
• watering when there is sufficient wind to disperse the odour
• watering at night when there are fewer people around, if wind is sufficient
• desynchronizing with other similar bore water use