How harmful are sewer gases?
104263
I just had a sewer gas leak in my home and read all about it.  Hydrogen sulfide is a deadly poisonous gas.  Mild symptoms include burning eyes and throat. Worse is headache and nausea.  Worst is asphixiation and death.  also methane is highly flamable!  Don't risk it.  If you smell a rotton egg smell, all a plumber!ASAP  many symptoms, even from mild exposure are irrreversible!(ex. brain damage and visual impairment)
936553
Gas-X and Listerine!?!
509398
Um...it could be bad. I wouldn't worry so much about animals and stuff; I'd be more concerned about microorganisms. They say that if you were to take out ALL of the microscopic life from underground and pile it on the surface of the planet, we'd have at least three feet of muck everywhere. That's a LOT of life! That's a LOT of living stuff to be farting! Now add that with all of the trillions of insects and other crawly thing, and add all of the animals and people and plants (can plants fart, I wonder? They're LIVING so I guess they're included in this question)...it would be one massive outpouring of methane. Might create a pretty foul odor for a long time.
1072455
I suspect it depends on the volume of the flatus.  More gas = more methane.
251951
Well, 0.0047 ppm is the lowest concentration there can be which people can still smell. 10.0000 to 20.0000 ppm starts to cause eye irritation. So if it does exist below that level(0.0047 ppm), it's completely harmless.\n\nBUT... If you've ever gotten a real good sniff of it(150.0000-250.0000 ppm), it may have paralyzed your olfatic nerve (smeller) so that you can't smell the gas anymore. You would still be able to smell other things, but for some reason it desensitizes you almost permenantly to the gas itself.\n\nDo you have an aquarium? Sewer gas leak in the house? This could cause low levels of the gas to exist, if they are disturbed. I don't know of anyway to detect the gas other than to buy an instrument made for that purpose.
858428
Nothing chemically should happen, outside of creating something that really smells.  Ammonia vapors can be hazardous, as can moth balls, whether they are napthalene based or p-Dichlorobenzene based, so try not to spend too much time sniffing them.  They will not create an explosive, although mothballs are flammable.
577906
The Methyl Iso Cynate i.e. HCNO is the most dangerous gas.\nIt kills lacs of people in Bhopal(MP, India) in 1989 and caused mutation to lacs.
608724
Sewers run to the sea after the treatment plants, and storm water sewers (run-off) do.  However, it is illegal to dump toxics in the sea.  They go to specific toxic landfills, are incinerated, or are recycled.
675532
OMG EEEEK! jump off a bridge into a vat of toxic waste, hopefully it will reverse this problem lol
741671
try the information on this website. http://www.epa.gov/oust/cat/sve1.htm
991569
Yes this is an important topic.\nthe amount is tiny really.\nwhy not try to blow up a balloon and never burst it then all th gas will be traped and not effect the environment\nx x x
1106966
Allmost all welding fumes are toxic good ventilation a must especially for galvanize welding man that will make u wish u were dead and not too good on the eyes either.
429253
If it generates more than 70ppm, then according to the EPA it is unsafe.  Personally, if you can smell the ozone, then it's unsafe.  This means that it's producing at least 30ppm.
925492
Typically sewage goes down into the pipes below your house/apartment and then those pipes join in with the main city sewer lines. Collectively, then the sewage goes to the treatment plant where it's treated, sorted into fertilizer, and then sent back into a stream/creek/wastewater receptical of some sort.\n\nIt can be dangerous to have a septic tank, as they are likely to leach nitrogen into the soils which cause environmental dangers.\n\nIt can be made safer if people are aware not to dump toxic chemicals into toilets/sinks.
131324
fall into an open sewer and die
522652
Feces contains harmful chemicals
104846
http://home.howstuffworks.com/sewer.htm