Hydrogen Sulfide Water Test

That Rotten Egg Smell in Your Water Is Not Just Unpleasant. It Is Telling You Something.

If your water smells like rotten eggs or sulfur, hydrogen sulfide is a likely cause but it is not the only one. Understanding what is actually producing the odor in your specific situation is the only way to address it correctly because the source determines the treatment.

Hydrogen sulfide is a colorless gas that dissolves in water and produces that distinctive rotten egg odor even at very low concentrations. It occurs naturally in groundwater in areas where organic matter decomposes in low oxygen environments, particularly in aquifers with high sulfur mineral content. It can also be produced by sulfur reducing bacteria living in your well, your plumbing, or your water heater. These bacteria feed on sulfur compounds and produce hydrogen sulfide gas as a byproduct. Sulfur reducing bacteria are a more common cause of this odor than most people realize and they require a different response than a geological source. A positive hydrogen sulfide result paired with a negative bacteria test points toward geology. A positive result with signs of bacterial activity points toward a biological problem that needs to be addressed directly.

Is Hydrogen Sulfide in Water Dangerous?

At concentrations typically found in private well water hydrogen sulfide is not acutely toxic when consumed. However dismissing it as merely a nuisance misses several important points.

The odor is a signal worth investigating. In some cases a sulfur-like smell is caused by sewage contamination entering the water supply which is a serious health concern. The smell alone cannot tell you which situation you are dealing with.

Hydrogen sulfide is also highly corrosive. It reacts with metals and causes significant damage to plumbing fixtures, copper pipes, water heaters, and appliances over time. The characteristic black staining on silver and tarnishing on brass and copper fixtures is a direct result of hydrogen sulfide exposure. At elevated concentrations hydrogen sulfide gas released from running water can also cause respiratory irritation, headaches, and nausea particularly in enclosed spaces with poor ventilation.

Why Does My Hot Water Smell Worse Than Cold?

Water heaters create an ideal environment for sulfur reducing bacteria. The warm temperature, the magnesium anode rod used to protect the tank, and relatively stagnant water all encourage bacterial growth. If your hot water smells significantly worse than your cold water your water heater is likely contributing to or amplifying the problem. Testing cold and hot water separately can help identify whether the source is geological, bacterial, or heater related.

How It Works

Order your test and we will mail you a sample collection kit with easy to follow instructions. Collect a water sample from your tap and send it back to our in-house laboratory. Results are delivered within 1 to 2 business days from the date your sample arrives at our lab.

Understanding Your Results

Every test includes a free consultation with one of our in-house water quality experts. Hydrogen sulfide results need to be interpreted in context. If your results indicate hydrogen sulfide we will walk you through the likely source based on your situation and what treatment options make the most sense. Aeration, activated carbon filtration, chlorination, and shock disinfection are among the most common approaches depending on the source and concentration. If bacterial activity is suspected we will recommend pairing this test with a bacteria test to get the complete picture.

This test is recommended for any well owner who has noticed a rotten egg or sulfur odor in their water, households where hot water smells significantly worse than cold, anyone who has noticed black staining on silver or tarnishing on copper and brass fixtures, homeowners who want to rule out sewage contamination as the source of an unpleasant water odor, and anyone who has had a positive bacteria test and wants to investigate whether sulfur reducing bacteria are contributing to ongoing water quality issues.