H2S

Common name: Hydrogen Sulfide

PPM: Parts Per Billion (how many H2S molecules per billion air molecules)

 

What is H2S?

 

• H2S is a highly toxic gas that has many negative effects on the body.

 

• It is commonly produced by crude oil and natural gas factories, and also by wastewater plants and poorly managed landfills. 

 

• The gas is produced when bacteria break down organic materials (like petroleum) in the absence of oxygen. 

 

What are the health effects of H2S? 

 

• Hydrogen Sulfide is irritating to humans specifically to the respiratory tract. The respiratory tract and lungs have delicate mucous membranes that are sensitive and easily irritated.

 

• Symptoms of short term exposure can include

  • Headache

  • Coughing, wheezing, shortness of breath

  • Nausea

  • Eye and skin irritation 

  • Damage to the central nervous system

 

• H2S does not accumulate in the body, but it can still cause long term problems. 

 

• Symptoms of long term exposure include 

  • Reduced attention span and lower motor functions

  • Convulsions

  • Coma 

    • These can cause death

 

What’s a safe amount?

 

• The US Occupational Safety and Health Administration, or OSHA, states that 20 ppm is the industry limit for exposure, with a limit of 10ppm for extended periods of 8 hours. 

 

• However, the ACGIH (American Conference of Governmental Industrial Hygienists) recommends a limit of 1ppm of long term exposure, and a short term limit of 5ppm. 

 

• Many people have reported headaches and irritation when exposed to 5ppm or less, lending credit to ACGIH's lower recommendations. 

 

• 0.1 PPM is enough to cause a rotten egg smell. 500PPM is enough to cause unconsciousness and death. 

 

How much H2S are we getting in the River Ridge/Harahan area? 

 

• LDEQ's Air monitoring station shows hourly records of H2S levels

 

• On most days, H2S sits at around 1-3ppb, but it often spikes to 5-7ppb. Some of the highest readings so far have been around 25ppb. 

 

•  These values are below the thresholds for danger. However, it is clear that constant, lifelong exposure to this chemical is having negative health effects on the River Ridge community. Widespread eye irritation, headaches, and tightness of breath experienced by residents are attributed to H2S poisoning. 

 

What can I do to protect myself?

 

• The best way to protect yourself is to use respiratory protective equipment, like masks, and eye protection to avoid irritation. If you smell rotten eggs in the air, you should try to limit your exposure to that air, and wear one of your coronavirus masks. 

 

Where does it come from?

 

• Jefferson Parish Landfill has been targeted as the main culprit producing H2S in the River Ridge area. Gas wells measured from this landfill contained as much as 2,000ppm of H2S, enough to kill someone instantly, and 25 times higher than that of a neighboring landfill. 

  • ​Outside the wells at ground level, H2S has been measured at up to 45-60ppm

  • This high concentration was caused by a buildup of hydrated lime, or potentially industrial waste that settled to the bottom of the landfill and began producing H2S. 

  • Gas capture systems have since been put in place, but their effectiveness is still uncertain. 

 

• Cornerstone Chemical also produces H2S as a byproduct of its chemical production. 

 

What does it smell like? How do I know when I'm breathing it? 

 

• H2S is invisible but it has an easily recognizable rotten egg odor.

 

• However, continuous exposure desensitizes you to its smell, and after a short time, you can no longer smell it at all. Because of this, you can never be certain whether there is H2S in the air. This is why having hourly air monitoring data is so important. 

 

How does wind speed & direction affect air quality?

 

• H2S gas is a heavy gas, it is heavier than air, and therefore it travels close to the ground, and may gather in low, enclosed areas, such as basements. Try to keep your windows and doors shut on bad days, to prevent high levels of H2S from entering your house.