Is Your Electric Dishwasher Poisoning You??

Do you have an electric dishwasher? Have you noticed 'spots' of white residue on your dishes? Ever wonder what that is, and what you're constantly ingesting, in small doses?

Let's find out! Most dishwasher detergents contain 4-8% phosphates [1] -- it's a main active ingredient. From the ingredients list for one very popular product:

Ingredient: SODIUM MONOHYDROGEN PHOSPHATE HEPTAHYDRATE (2:1:1:7); (SODIUM PHOSPHATE)
NIOSH (RTECS) Number: WC4600000
CAS Number: 7682-85-6
[2]

But wait! That's not a valid CAS (Chemical Abstracts Service) identifier number! Hmm, perhaps it's a typo:

NAME: SODIUM PHOSPHATE DIBASIC, HEPTAHYDRATE
CAS #: 7782-85-6
RTECS #: WC4600000
SODIUM MONOHYDROGEN PHOSPHATE HEPTAHYDRATE (2:1:1:7)
[3]

Okay, now let's look up the Material Safety Data Sheet (MSDS) for CAS Number 7782-85-6:

Potential Health Effects
Eye: May cause eye irritation.
Skin: May cause skin irritation.
Ingestion: May cause gastrointestinal irritation with nausea, vomiting and diarrhea.
Inhalation: May cause respiratory tract irritation.
Chronic: No information found.

Toxicological Information
Carcinogenicity: Not listed by ACGIH, IARC, NIOSH, NTP, or OSHA.
Epidemiology: No data available.
Teratogenicity: No data available.
Reproductive Effects: No data available.
Neurotoxicity: No data available.
Mutagenicity: No data available.
Other Studies: No data available.
[4]

Well, not much information there! Perhaps we're barking up the wrong tree:

CAS# 7782-85-6 is not listed on the TSCA inventory. It is for research and development use only.
[5]

Huh? What's that? Why? Oh:

CAS# 7782-85-6 is not on the TSCA Inventory because it is a hydrate.
It is considered to be listed if the CAS number for the anhydrous form is on the inventory (40CFR720.3(u)(2)).
[6]

Ah! We should be looking for CAS# 7558-79-4, the anhydrous form. That must be what they're using in the dishwasher detergent, anyway, since the other version is for research and development use only. Let's see what the State of New Jersey has to say:

CAS# 7558-79-4

Cancer Hazard
* According to the information presently available to the New Jersey Department of Health and Senior Services, Sodium Phosphate Dibasic has not been tested for its ability to cause cancer in animals.

Reproductive Hazard
* According to the information presently available to the New Jersey Department of Health and Senior Services, Sodium Phosphate Dibasic has not been tested for its ability to affect reproduction.
[7]

What?!? Not tested? And we're ingesting trace amounts of this stuff with every meal? How about long-term toxicology?

CAS No.: 7558-79-4 (Anhydrous); 7782-85-6 (Heptahydrate)

Chronic Exposure:
May sequester calcium and cause calcium phosphate deposits in the kidneys. Chronic ingestion or inhalation may induce systemic phosphorous poisoning. Liver damage, kidney damage, jaw/tooth abnormalities, blood disorders and cardiovascular effects can result.
[8]

Uh-oh.

I use my dishwasher all the time. I had my dishwasher repair man do a routine maintenance check of my dishwasher (hey, it was free with the warranty. So why not?) He said that I was putting too much soap in the dishwasher. He said not to put any soap the prewash and to just put enough soap in the main bin to cover the bottom. DO NOT fill it to the top. Since then, no more soap residue.

I had intestinal problems several years ago. My GI specialist suspected it was either artificial sweeteners, dairy, or the dishwasher soap not being thoroughly rinsed off the dishes. I've had no problems since I stopped filling the dishwasher soap bin to the top.

Just about anything will kill you if you ingest enormous amounts of it. I don't think I'm going to panic over the dishwasher soap.

reply to post by mistressofspices


Putting vinegar where jet dry goes helps too. It's inexpensive and works well.

[edit on 27-7-2008 by Swingarm]

reply to post by mistressofspices


You are so right about this. My dishwasher has 2 compartments for soap and I only fill up 1/3 of one compartment - no residue, clean dishes. They just make the compartments big so you'll use more soap, duh.

It's the same with laundry detergent. Don't use that huge scoop they give you. I put between 1/4-1/3 cup (measuring cup) of laundry soap in each load and the clothes come out pristine. If you use the scoop that comes in the laundry detergent the soap doesn't rinse out of the clothes and you have to buy more much sooner than you should.