Arsenic in well water

[johnny potatoes]

So I just moved and the well water contains arsenic. EPA safe limits for human consumption are .01 ppm as of 2001, before that the safe level was .05 ppm. My water was just tested at .015 ppm.
Keep in mind these are for human consumption, I couldn't find anything for aquarium fish. My assumption would be its not desirable.

Is arsenic even toxic to fish?
If so, at what levels does it become an issue?
This and any other info would be a great help. Thanks.

 

[Drstrangelove]

https://www.pwrc.usgs.gov/eisler/CHR_12_Arsenic.pdf

Arsenic at that level .015 ppm (.015 mg/L, or 15 ug/L) doesn't appear by itself to be lethal over the course of 4-8 weeks. But at higher levels that changes.

LC50 over 4-7 days was reached at levels of 14-25 ppm for goldfish, flagfish, channel catfish, trout, brook trout and flathead minnows.

But bluegills died in 16 weeks at 0.7 ppm, goldfish showed behavioral changes at 0.1 ppm, while 50% of rainbow trout embryos died in 4 weeks at 0.54 ppm.

Amphibians appear to be far more sensitive.

However, like most compounds or elements, it can react to things like temperature, pH, salt, medicines and many other chemicals to become far more lethal.

I'd probably get a full water report, or test the water using some test fish for a few months. And still, you'll have to be careful in adding medicines or salts to the tank until you research the interaction.


On a different note, while nitrosomonas bacteria are not affected by those levels of arsenic, arsenic does negatively impact nitrobacter, even at 0.1 mg/L. You can see the attached report.
https://specialcollections.nal.usda.gov/sites/specialcollections.nal.usda.gov/files/04466.pdf

 

[johnny potatoes]

https://www.pwrc.usgs.gov/eisler/CHR_12_Arsenic.pdf

Arsenic at that level .015 ppm (.015 mg/L, or 15 ug/L) doesn't appear by itself to be lethal over the course of 4-8 weeks. But at higher levels that changes.

LC50 over 4-7 days was reached at levels of 14-25 ppm for goldfish, flagfish, channel catfish, trout, brook trout and flathead minnows.

But bluegills died in 16 weeks at 0.7 ppm, goldfish showed behavioral changes at 0.1 ppm, while 50% of rainbow trout embryos died in 4 weeks at 0.54 ppm.

Amphibians appear to be far more sensitive.

However, like most compounds or elements, it can react to things like temperature, pH, salt, medicines and many other chemicals to become far more lethal.

I'd probably get a full water report, or test the water using some test fish for a few months. And still, you'll have to be careful in adding medicines or salts to the tank until you research the interaction.


On a different note, while nitrosomonas bacteria are not affected by those levels of arsenic, arsenic does negatively impact nitrobacter, even at 0.1 mg/L. You can see the attached report.
https://specialcollections.nal.usda.gov/sites/specialcollections.nal.usda.gov/files/04466.pdf

Thanks Doctor, that's very useful info you have provided. I'm having a water filter installed for our consumption that removes arsenic and other cooties. I was trying to figure out if I needed to treat the fish water as well. Perhaps I can use half treated, half not treated for water changes.
One question though, LC50 you listed and I saw that in the PDF but can't figure out what exactly that means. Don't see that as an issue as 14 ppm is nearly 1000 times what is in my water. Just curious, thanks again for your help

 

[Drstrangelove]

One question though, LC50 you listed and I saw that in the PDF but can't figure out what exactly that means.

http://www.ccohs.ca/oshanswers/chemicals/ld50.html

I used LC50, but technically I should have said LD50. Similar concept, but not technically correct since we are talking water.

Although, LD50 refers to dosage as if the test subject is drinking it or being injected, it's used in the articles describing the ingesting of water. This is common in evaluating things like ammonia poisoning, nitrite poisoning, etc. even if the subject is absorbing it through the skin.

 

[Icridr81]

So I just moved and the well water contains arsenic. EPA safe limits for human consumption are .01 ppm as of 2001, before that the safe level was .05 ppm. My water was just tested at .015 ppm.
Keep in mind these are for human consumption, I couldn't find anything for aquarium fish. My assumption would be its not desirable.

Is arsenic even toxic to fish?
If so, at what levels does it become an issue?
This and any other info would be a great help. Thanks.

Johnny I see your issue with arsenic and iam also in this position at the moment Iam wondering how you've made out with your tank and if you used your well water? Thanks.

 

[johnny potatoes]

Johnny I see your issue with arsenic and iam also in this position at the moment Iam wondering how you've made out with your tank and if you used your well water? Thanks.

Sorry, can't help you. I haven't set up a tank yet. My plan is to use the well water and see what happens. Let me know how it works out for you. Thanks