Is it safe to drink from stainless steel?

September 19, 2009 9:54 AM

Trying to be safer and heeding the advice of many, I threw out all my plastic water bottles and bought new stainless steel ones including this stainless steel cup. On the cup (but not on the bottles), there was the California Proposition 65 warning that "This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm."

Why? I thought the whole point of switching to stainless steel was that it was not a carcinogen. Is the manufacturer just being overly cautious? Is there some difference between the cup and the bottles? Is this something for my (worry-prone) wife to worry about?

posted by pasici to health & fitness (9 comments total)

At least it's safe to go back to plastic until it's not safe again, and it's safe to drink from stainless steel until it's not again as well.

Stick with a name brand stainless bottle and I'm guessing the lid is made up from some sort of plastic material or has a silicone washer on it that contributes to that warning. There's a lot of hype around all of this, it's possible the stainless manufacturer coats the inside of the bottle with something that causes the warning.

So! Stick with something like Kleen Canteen that isn't coated on the inside...
posted by iamabot at 10:20 AM on September 19

Here's the scoop on Cal Prop 65-- bad science, bad law, bad enforcement. There is a list of chemicals. If a product contains any measurable level of one of those chemicals, the retailer has the duty to warn the purchaser. California allows private parties to identify products where the warning is not present, and turn in "60 Day Notices" to the Attorney General's office. If the Attorney General finds that the product does contain non-zero amounts of that chemical, then the retailer/manufacturer has to pay the attorney's fees of the "bounty hunter" and a nominal fine.

The bounty hunters target a product category, and then slap dozens or hundreds of 60 day notices on people in related businesses-- roofing contractors, nail parlors, etc. The bounty hunter and their attorney get about $15,000 per business for a simple settlement.

About 10% of the Cal Prop 65 60 day Notices have merit and are in the best interests of the people. There are some products that leach heavy metals or endocrine disruptors into the human user. Good science, and a good law, would simply prohibit the leachable material from that product category, or set threshold levels.

The US Govt has good laws regarding stainless steel that can be used in food contact. Food contact items have to be made from Food Grade materials. [of course, the FDA permits medical grade PVC tubing to contain phthalates, but that's another story]

So, to make a short story long, iamabot is correct. The insulation material or a sealing ring is probably made from a plastic that contains a material certified as safe by the FDA. however, the simple presence of some chemical requires a warning in California. You should be OK if all the food contact surfaces are stainless steel.

I use Kleen Kanteen.
posted by ohshenandoah at 10:46 AM on September 19 [11 favorites]

California's Proposition 65 is not without controversy. Proposition 65, for example, requires that consumer warnings be placed on some consumer items about which other U.S. states have concluded there is no sufficient reason to warn consumers. My point here is not to dismiss Proposition 65, but to suggest that you learn more about this statute before taking its edicts as automatic gospel.
posted by applemeat at 11:12 AM on September 19 [3 favorites]

forgive me.
posted by mecran01 at 6:45 PM on September 19

Note that the OP is talking about the cup, not the bottle. The cup (see link) is made of stainless steel. It is insulated because it is double-walled. From the picture, I can see no other material than stainless steel. If this cup is truly make 100% of stainless steel, I can see no possibility of carcinogens. Can anyone else?
posted by exphysicist345 at 8:15 PM on September 19

Cali's proposition 65 frankly to me seems a little nuts. I went to a training session for some hardware in a place just south of San Jose, and the elevator had a lengthy warning of a very similar tone about cancer causing substances, etc. etc. etc. Eventually after staring at it with a WTF? look on my face for about a minute I figured out they were trying (poorly) to say it's possible someone might be smoking a cigarette somewhere in the hotel, and I should be warned that might kill me, or not.

IMHO, these warnings are counterproductive since after you realize one of them is ridiculous, you start to think all other similar warnings just might be as well. Boy who cried wolf and all that.
posted by barc0001 at 2:21 AM on September 20

I would bet that the warning is more that they can't prove it doesn't have the substances.

Or, and I bet this is it- the handle, or the method used to fasten it, isn't pure stainless steel.
posted by gjc at 4:56 AM on September 20

Stainless steel gets the label because it has chromium and nickel (pdf of all items receiving the label). As best as I can tell, this is a danger to the people who manufacture items made of steel, as it can be inhaled during welding (for example, see this pdf Material Safety Data Sheet, this pdf of a Prop 65 fact sheet, and most of these items).
posted by Houstonian at 5:13 AM on September 20

I've been drinking from steel/aluminum/glass pitchers all my life. Even from silver glasses at times. All safe :)
posted by bbyboi at 12:51 AM on September 21