Using metal garbage can as feeder?

[Sondraa]

I was reading a post about people accidentally giving their duck flock zinc poisoning by using a galvanized product. Over time water erodes it and it leaches zinc into the soil, water, feed...everything around it.

 

[Al Gerhart]

I would need to see proof of such a thing. Some of us grew up drinking water out of a galvanized bucket filled with water drawn with a galvanized well trap door bucket. Zinc by the way is an essential element, far more likely to be harmed from not enough zinc than too much.

But I looked and there are a bunch of bloggers using the topic to generate clicks and traffic but once you dig down into the studies it concerns OLD MINING AREAS with huge amount of mining pollution.

One Washington State study initially published concerns- https://apps.ecology.wa.gov/publications/SummaryPages/1703018.html
-only to backtrack and report that they had been wrong by orders of magnitude. https://apps.ecology.wa.gov/publications/SummaryPages/1903008.html

For those without a scientific background, one order of magnitude means overestimating or over counting by a factor of ten. Two orders of magnitude would be 100 times less, three orders of magnitude would be 1,000 times less.

Humans need 8 to 12 mgs per day of zinc. Water should have less than 5mg per liter of zinc and anyone dumping more than 1,000 pounds of zinc into the environment needs to report the dumping to the EPA. Doesn't sound like zinc is that much of a problem.

But, to be safe lets look at one study that followed wild mallards living in one of those massive polluted mining sites. They took wild mallards, fed them between 3,000 and 12,000 ppm of zinc per day and sure enough the ducks got quite sick and even died. But that 5 mg of zinc per liter of water is only 5 ppm, the EPA limit where it is NOT poisonous but beneficial, past that it becomes a taste issue.

So feeding ducks 600 to 2400 times the recommended level of zinc can be harmful. Don't do that.

The other issue is bio availability, under what conditions does zinc or heavy metals leach into water or soil or through skin contact. Only when you have extreme acidic or alkaline conditions or very high heat. Galvanized buckets and containers are FDA safe as long as acidic food is not in contact with the surface.

Then consider the amount of zinc used for coating. For a thin coating such as the tin used on a tinned steel food can, six ounces per ton of steel. If you had a hot dipped galvanized bucket, maybe a fraction of an ounce per bucket. You would have to scrape off the zinc from the bucket every day to get close to the lethal dose.

 

[Sondraa]

See for yourself. Link below. https://www.backyardchickens.com/threads/sick-duck.1652107/

 

[Sondraa]

And this article about halfway down about how to avoid giving your ducks zinc poisoning. http://www.majesticwaterfowl.org/mmissue30.htm

 

[Sondraa]

See attached

 

[Sondraa]

Most people don't get lab tests so it goes undiagnosed or misdiagnosed.

 

[U_Stormcrow]

I would need to see proof of such a thing. Some of us grew up drinking water out of a galvanized bucket filled with water drawn with a galvanized well trap door bucket. Zinc by the way is an essential element, far more likely to be harmed from not enough zinc than too much.

But I looked and there are a bunch of bloggers using the topic to generate clicks and traffic but once you dig down into the studies it concerns OLD MINING AREAS with huge amount of mining pollution.

One Washington State study initially published concerns- https://apps.ecology.wa.gov/publications/SummaryPages/1703018.html
-only to backtrack and report that they had been wrong by orders of magnitude. https://apps.ecology.wa.gov/publications/SummaryPages/1903008.html

For those without a scientific background, one order of magnitude means overestimating or over counting by a factor of ten. Two orders of magnitude would be 100 times less, three orders of magnitude would be 1,000 times less.

Humans need 8 to 12 mgs per day of zinc. Water should have less than 5mg per liter of zinc and anyone dumping more than 1,000 pounds of zinc into the environment needs to report the dumping to the EPA. Doesn't sound like zinc is that much of a problem.

But, to be safe lets look at one study that followed wild mallards living in one of those massive polluted mining sites. They took wild mallards, fed them between 3,000 and 12,000 ppm of zinc per day and sure enough the ducks got quite sick and even died. But that 5 mg of zinc per liter of water is only 5 ppm, the EPA limit where it is NOT poisonous but beneficial, past that it becomes a taste issue.

So feeding ducks 600 to 2400 times the recommended level of zinc can be harmful. Don't do that.

The other issue is bio availability, under what conditions does zinc or heavy metals leach into water or soil or through skin contact. Only when you have extreme acidic or alkaline conditions or very high heat. Galvanized buckets and containers are FDA safe as long as acidic food is not in contact with the surface.

Then consider the amount of zinc used for coating. For a thin coating such as the tin used on a tinned steel food can, six ounces per ton of steel. If you had a hot dipped galvanized bucket, maybe a fraction of an ounce per bucket. You would have to scrape off the zinc from the bucket every day to get close to the lethal dose.

^^^ this is why I come to BYC. Thank you Al for providing a reasoned and well supported response.

 

[U_Stormcrow]

W/ all due respect @Sondraa you linked to an anecdote and a self-diagnosed suspicion (from someone who previously self-diagnosed the duck as having lead poisoning - maybe not the most reliable of opinions).

I'll take my advice from Paracelsus, "the dosage is the poison", read the studies, and make my own risk management assessment as required. In sufficient quantity, EVERYTHING is fatal. Salt, Water, Oxygen, any Vitamin or Mineral you choose to pick.

 

[AGeese]

I can tell you from experience of doing this for my cousin that after a time if you don't clean these out regularly the galvanization errodes, and the metal rusts. In addition residual feed that never makes it out gets crushed from the weight and turns moldly.

 

[U_Stormcrow]

I can tell you from experience of doing this for my cousin that after a time if you don't clean these out regularly the galvanization errodes, and the metal rusts. In addition residual feed that never makes it out gets crushed from the weight and turns moldly.

The bottoms rusting out are why I don't use galvanized cans - my climate eats them alive. Not zinc concerns.

{for reference, my 52+ inches of rain per year, frequent 80*+ temps, and clay soils take about 15 months to dissolve galvanized hardware cloth, less than 6 to dissolve chicken wire. Likely have more zinc in my environment from the memory of old predator protection than the one galvanized pail I used to own}