Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


EPDM question

EPDM question

EPDM question

Hello all,

I have been reading your forum in an attempt to learn more about EPDM and what contaminants various formulations might leach to water. Please forgive me for not being an engineer and posting this to your forum. I'm desperate for knowledgeable help and I don't know who to ask.

To begin, I'm 6 months pregnant. To my horror, I recently learned that for the first 5 months of my pregnancy and the year before, the 6-8 glasses of water I drank at work every day reached the faucet by a 200 ft EPDM hose that sat on a sunny hillside. According to the manufacturer, this hose is not intended for potable water. The hose was quietly installed after the main water pipe broke and management decided not to spend any more money on this site. Now I'm very concerned that possible contaminants could have affected my child. I would like to ask for appropriate testing.

After I complained, my employer rashly had an (unrepresentative) sample tested for phthalates and BPA. But from what I've recently learned, BPA and phthalates are very unlikely to be found in EPDM anyway.

Please correct me if what I'm saying is wrong. EPDM formulations typically seem to include:

-- raw polymer
-- filler (?carbon black)
-- softener (?paraffinic oil)
-- vulcanization agents (?sulfur type)
-- other things?

From what I read, EPDM is seen as a pretty safe material but should I be concerned about contaminants considering water sometimes sat over a weekend on a sunny hillside? If so, what contaminants would be appropriate to look for in the water?

I don't have a chemistry background so I can only guess.

Any thoughts or suggestions would be a huge help to me. Thank you.


RE: EPDM question

Rubber parts intended for use with potable water MUST go through some of the most stringent testing known to the rubber industry. If the manufacturer of the hose has told you it is not suitable for potable water then it should not be used to supply drinking water. In my opinion, you should get the water supply switched off to the faucets first, then contact your local environmental or health and safety people. Finally, consider suing your company for knowingly endangering your health.

RE: EPDM question

Thank you so much for writing back. The hose has now been disconnected and the pipe repaired. But I don't know what the potential exposure has been throughout my pregnancy and this is terrifying. I'm trying everything I can think of to have appropriate testing done. I'm looking for an attorney now who will stand up for me and help me demand it. My employers seem satisfied with their BPA and phthalate tests which I believe are probably not relevant for this hose. Any thoughts as to what relevant water testing should be looking for in water from an EPDM hose? I imagine this is a complicated question without an easy answer.

RE: EPDM question

EPDMs suitable for potable water use as little ingredients as possible to avoid failing the tests. Many additives which would make processing easier also interfere with taste (of the water) and bacterial growth. You might want to test the inside of the tube for bacteria/funghi (I have no idea about the cost of such a test).
Calcium oxide is often used in normal hoses, but as little as possible when in formulations for potable water.
Antioxidants as TMQ might be used, antiozonants are normally not necessary in EPDM. Nitrosamines formed during the vulcanisation might be present, depending on the accelerators used.
White fillers can also be used in combination with carbon black. Normally these are harmless.
EPDM types with high amount of diene or blended with oils cannot be used for food/water contact.

It was a mistake to use this hose, but if I were you I would try not to be overly concerned. The stress might have a bad effect too.

Request the MSDS of the rubber used in the hose. Do not expect the full formulation, but look if there is a mention that the formulation can be given to a doctor on request (+ it should mention contact details). The rubber hose producer made no mistake as he was not the one to install the hose.

RE: EPDM question

This is very helpful. I so appreciate it. I'm trying to be more calm and may have someone's ear at work who will agree to more informed testing. I'm going to go work on finding a MSDS sheet tomorrow. Thank you.

RE: EPDM question

IMO it is unlikely that biphenol A and phthalates have been used in this hose so the previous testing would have been a waste of time and money. Products used for potable water can only be tested by one of a handful of certified laboratories in the world.

RE: EPDM question

Tests to determine if a rubber is suited for potable water differ from country to country. I am not 100% certain, but I think the ANSI NSF 61 and AWWA FM/UL standards are used in the US.

RE: EPDM question

Thank you for this suggestion. I have been in touch with NSF to ask about testing to NSF 61. Without knowledge of the specific EPDM formulation, the NSF61 document I was sent lists under required analyses: "GC/MS, VOCs, phenolics (by GC/MS base/acid scan), phthalates, PNAs, Nitrosamines"

And as a footnote to Nitrosamines in this list "Analysis for N-Nitrosodimethylamine, N-Nitrosomethylethylamine, N-Nitrosodiethylamine, N-Nitrosodi-npropylamine, N-Nitrosopyrrolidine, N-Nitrosomorpholine, N-Nitrosopiperidine, N-Nitrosodi-n-butylamine and N-Nitrosodiphenylamine are required when material is sulfur cured. Analysis shall be in accordance with USEPA Method 521 (USEPA-600/R-05/054)." I believe from off the record conversations with an engineer familiar with the particular formulation that the material in this hose was sulfur cured. I am worried about Nitrosamines and want thorough testing for these. Are the sort of Nitrosamines and levels that can leach from rubber along the same order of magnitude as I might get from eating bacon and washing it down with a beer (though I'm vegan and can't drink : )

I've sent the NSF61 information to my employer and asked them to hire someone qualified to see that testing is done to these standaards. I've also finally made contact with the appropriate contact person at California Department of Public Health and hope to hear from him next week.

Thanks to all of of you for your input. Any additional thoughts?

Happy 4th of July

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close