What is hydrogen sulfide, gas causing 'rotten egg' smell near U.S.-Mexico border?
SAN DIEGO (FOX 5/KUSI) -- The Tijuana River sewage crisis has been happening for decades and has been at the center of ongoing environmental and public health policy discussions between politicians at the city, state, county and federal levels.
For several years, residents in South Bay communities have had to live with the stench and other inconveniences stemming from the raw sewage flowing from south of the U.S.-Mexico border and into San Diego County.
- The Nexstar Media Wire video above explains what the different air quality categories mean.
County officials say the odor is due to an elevated presence of hydrogen sulfide (H2S), which is described as a colorless gas with a "rotten egg" smell.
The San Diego County Air Pollution Control District (SDAPCD) measures the amount of H2S in the air and notifies the public about any potential impacts.
Here's what you need to know about hydrogen sulfide.
Why is the odor more noticeable on some days than others?
The smell of H2S might be stronger on some days based on a variety of factors. These include the amount of untreated sewage flowing in the Tijuana River, as well as how close someone is to the flow.
Other factors that might cause the odor to change on any given day include wind speed/direction, humidity and temperature, according to county officials.
How could it affect my health?
The SDAPCD says "there is no scientific evidence to suggest that exposure to the odor will cause lasting impacts to a person's health." However, it could cause brief symptoms such as headaches and irritation in the eyes, nose, throat and/or lungs.
People who are sensitive to the smell may also experience dizziness, nausea, vomiting or abdominal discomfort. Those with pre-existing lung or heart conditions might get more severe or frequent symptoms. If any symptoms worsen, county officials advise you to seek medical care.
How would I know if I have been exposed to H2S?
According to the agency, H2S and its breakdown products can be measured in blood and urine. However, because they tend to leave the body quickly, measurements of H2S in the body are unable to predict long-term health effects that could develop from being exposed to the gas.
What should I do if H2S is present in my community?
County officials advise anyone who resides in an area impacted by H2S to stay up-to-date with the current levels on the SDAPCD website and make informed decisions.
If the odor is bothersome, you are urged to limit spending time outdoors, keep doors and windows closed, and use air conditioning or air purifiers if available.
Households that are the most impacted by odors linked to the Tijuana River sewage crisis may qualify for a free home air purifier through the county's Air Improvement Relief Effort Program (AIRE). More information can be found here.
