10/26/04

> On Tue, 26 Oct 2004 11:28:32 GMT, Michael Plant wrote:
>
>> Dog Ma /25/04
>> reply w/o spam
>>
>>> Derek:
>>>> Bottled water is *not* mineral free. If you want water with no minerals,
>>>> you need to buy distilled.
>>>
>>> Or deionized, which you can also make at home with a cartridge gadget. Or
>>> rainwater.
>>>
>>>> Personally, I'm still struggling with lime scale on our electric tea
>>>> kettle. Unfortunately, it's around the rim, and it's in a very difficult
>>>> place to soak in vinegar.
>>>
>>> Sodium salts of ethylenediaminetetraacetic acid (EDTA) - for those not
>>> afraid of "chemicals" - are a universal descaling agent that rapidly
>>> chelates polyvalent ions like those in lime deposits. It's cheap at hardware
>>> stores, but wear gloves and keep out of eyes. A spongeload may remove
>>> deposits very quickly, or make a "poultice" in a rag or paper towel and
>>> leave it for a while. Some dishwasher detergents are loaded with that,
>>> zeolites, phosphates and other hard-water ion eaters. When I have crusted
>>> old cookware, I usually just soak it for a few hours in hot water with a
>>> cupful or so of the stuff. Watch out - can eat aluminum and some other
>>> metals.
>>>
>>> -DM
>>>
>>>
>> Dog Ma,
>>
>> Is this stuff you're describing environmentally sound? After all, that acid
>> has 11 syllables, if I've counted correctly; a bad omen.
>>
>> Michael
>
> EDTA is a skin, eye and respiratory irritant. When I worked in a research
> lab, we used it for a lot of different things. But it was always treated as
> an irritant.
>
> But it's not considered particularly toxic. Even so, it's not something I
> personally want around my tea water. I've seen what it can do.


Thanks Derek. I knew eleven syllables couldn't be trusted.

Michael

On Tue, 26 Oct 2004 13:20:52 GMT, Michael Plant wrote:

> 10/26/04
>
>> On Tue, 26 Oct 2004 11:28:32 GMT, Michael Plant wrote:
>>
>>> Dog Ma /25/04
>>> reply w/o spam
>>>
>>>> Derek:
>>>>> Bottled water is *not* mineral free. If you want water with no minerals,
>>>>> you need to buy distilled.
>>>>
>>>> Or deionized, which you can also make at home with a cartridge gadget. Or
>>>> rainwater.
>>>>
>>>>> Personally, I'm still struggling with lime scale on our electric tea
>>>>> kettle. Unfortunately, it's around the rim, and it's in a very difficult
>>>>> place to soak in vinegar.
>>>>
>>>> Sodium salts of ethylenediaminetetraacetic acid (EDTA) - for those not
>>>> afraid of "chemicals" - are a universal descaling agent that rapidly
>>>> chelates polyvalent ions like those in lime deposits. It's cheap at hardware
>>>> stores, but wear gloves and keep out of eyes. A spongeload may remove
>>>> deposits very quickly, or make a "poultice" in a rag or paper towel and
>>>> leave it for a while. Some dishwasher detergents are loaded with that,
>>>> zeolites, phosphates and other hard-water ion eaters. When I have crusted
>>>> old cookware, I usually just soak it for a few hours in hot water with a
>>>> cupful or so of the stuff. Watch out - can eat aluminum and some other
>>>> metals.
>>>>
>>>> -DM
>>>>
>>>>
>>> Dog Ma,
>>>
>>> Is this stuff you're describing environmentally sound? After all, that acid
>>> has 11 syllables, if I've counted correctly; a bad omen.
>>>
>>> Michael
>>
>> EDTA is a skin, eye and respiratory irritant. When I worked in a research
>> lab, we used it for a lot of different things. But it was always treated as
>> an irritant.
>>
>> But it's not considered particularly toxic. Even so, it's not something I
>> personally want around my tea water. I've seen what it can do.
>
>
> Thanks Derek. I knew eleven syllables couldn't be trusted.
>
> Michael

Dog Ma is right - wear gloves. However, the warning about eating metals is
also accurate. EDTA is a no-no for:

copper, copper alloys, nickel, aluminium

It also reacts with strong oxidizing agents or strong bases.

--
Derek

Every dark cloud has a silver lining, but lighting kills hundreds of people
each year who are trying to find it.

> >>> Is this stuff you're describing environmentally sound? After all, that
acid
> >>> has 11 syllables, if I've counted correctly; a bad omen.

The IUPAC name for table sugar is half a page long. Of course, people argue
about the safety of sugar. Arsenic is technically called arsenic. Draw your
own conclusion.

EDTA is pretty OK environmentally, and the grams you'd add to the kilotons
already dumped daily wouldn't matter anyway. It's also been used in common
foods for many years.

> Dog Ma is right - wear gloves. However, the warning about eating metals is
> also accurate. EDTA is a no-no for:
> copper, copper alloys, nickel, aluminium

-But not quickly except with aluminum. What it will do is remove a thin
passivating layer of oxides, dirt, soap scum and scale to allow fresh
corrosion, as someone else here reported happening in a cleaned kettle.

DM