Does PEX Piping Affect Drinking Water Quality?

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Subject: Anecdotal Evidence

It might be helpful if everybody put down the brand of pex used. If known the type of pex that brand is such as, pex a, b, or c. Then if known you could add if the water is treated with chlorine? What the acidity level of the water is? How the taste and smell of the water is?

This would be helpful for now until the science catches up with the building industry.


Subject: Copper?

Though copper was found to be a great replacement for lead pipe since it was semi soft and lasted fairly well against low corrosive elements this doesn't mean copper is perfectly safe over other materials. Lead pipe was only really unsafe when exposed directly to water. If minerals built up in lead pipe then it was not so bad. Copper is not healthy in large amounts either. Just because copper lasts for years does not make it healthy. PEX is similar in health concerns where the amount of material leaving into water is considered safe so long as it does not have time to sit and concentrate. Being sure you have potable water safe PEX you are just as safe as the supply of water fed into the PEX. Ideal situation would be SS, or Stainless Steal in 304 grade or 316 designed with smooth walls and correctly connected for water supply. Given all the information I would rather have SS over anything but no industry is built around supply of SS for residential and so I would fall back to next safest and versatile material. Either copper or PEX is going to have health issues, but I suspect if you use the correct rated PEX-A on non-corrosive water you will have no more health issues over copper and perhaps even less. Be sure to install good quality PEX that is complaint with use in the environment it's meant for.

A Katz

Subject: Re Photo of alleged pex pipe

I think you will find that the pipe in the photo is actually PVC and not PEX and additionally, although it is hard to see clearly, I'm pretty sure it is sewer pipe and not water supply pipe at all. A quick check of the Heritage Plastics web site indicates they don't appear to manufacture water supply pipe, and certainly not PEX. To paraphrase the cutline under that photo, maybe "It's smart to actually know what pipe you're photographing" before you start offering a viewpoint.

Donald Wayne Kellar

Subject: Euro-water is different-no chlorine

Some have wondered why PEX is popular in Europe. As I understand it, Western Europe uses ozone (O3) as a disinfectant, while the USA uses chlorine (Cl2). Ozone quickly decomposes into harmless molecular oxygen (O2), while chlorine remains in the water, altering the pH of the stream, and leaches out the antioxidants and catalyst residues unique to PEX. My PEX water only smells bad in the summer, when water treatment facilities routinely increase the chlorine levels to cope with algae and bacteria that thrive in the warmer temperatures.

tim boehm

Subject: water in pipes

We bought a house that had been sitting for two years, it had the old galvanized steel pipes and a 500 ft run of them from our meter to the house. I would rather have drank my own urine even someone else's than drink that water. Well it took a few days before it was drinkable. As a plumber I have always installed copper, most recently went to cpvc and now to pex (doing my retirement house now). Well all I can say is only time will tell!


Subject: My PEX is great

I replaced older galvanized piping with PEX and it is great. No more smell, no rust.

We drink bottled water that has been sitting in plastic containers for months at a bottling company, the store, our house. Most of these bottles are also Polyethylene. What's so special about PEX Polyethylene?

Roger Zeise

Subject: PEX

Everything around us is being contaminated to one degree or another. Certainly as I sit here the PEX tubing in my apartment complex is leachng out bad crap into the water that I drink and wash with. How much of this crap our bodies can tolarate differs from body to body. How much that is being leached out differs from manufacturer to manufacturer. The cheaper the cost the more we can expect to lose in water quality. What happened in the flooring industry is happining in the plumming industry. Cheaper water delivery systems adds up an unhealther society


Subject: Filter won't work

Some above comments say they have whole-house filters and can't understand why the PEX could still affect their water. Well the filter is only helping the water coming in to the main line of the house, then it goes through the PEX tubing to get to your faucets. So the filter does nothing about what the PEX might leach into the water. The only way to help that is to have the filter under each sink leading to the faucets.


Subject: PEX tubing

PEX is cross-linked polyethylene and is not the source of smell or taste in water. That would be a water quality issue. Contact your local water conditioning professional to test your water and make a recommendation.


Subject: No taste or smell from pex

We had our 65-year-old galvanized pipes replaced with pex several months ago and from the start have had no issues with taste or smell. No change from before. We can have earthquakes here, so the flexibility of pex is an advantage in that respect as well as in needing fewer holes in walls and basement ceilings to install. I still think it's a good idea, whatever your pipes are made of, to let the water run for a bit to flush the pipes if you're going to ingest it. Fill and draw from glass or stainless steel storage containers to avoid the waste, if that's a concern where you live. As for pex, probably the best advice is to compare brands, if there is a way to do that. Ours continues to be fine.

teddy wetherby

Subject: Pex tubing and filters

I have Pex in my home have not noticed and smells or foul taste. I have a whole house filter attached to it. I have been told and read an article that Pex can leach into your drinking water. I am being told it leaches phthalates (plasticizers i.e., plastic softeners), which are estrogen mimicers. Will my filters remove these contaminants I can not find anywhere on the internet anything about this issue of Pex with whole house filters.


Subject: your filter does nothing

Your whole house filter does nothing for filtering the lines inside of your home. They are installed on the inlet line to the house the the water is distributed via the PEX tubing after the filter. You would need a point of use filter to take out anything coming out of the tubing. Its all false gloom and doom they have used this in Europe for over 30 years. Just some one didn't pay enough to get the proper blessing so they put out this BS.

Darrell Thomas

Subject: PEX plumbing, water supply piping

Isn't milk jugs, various food containers, Ice-maker tubing, water filter tubing, medical tubing, etc., etc. made out of the same and/or similar material.

Ray Cole

Subject: PEX Pipe and Water

We had our home plumbing (copper pipes) replaced with PEX about four years ago, and the water still smells terrible. I would rather have paid the extra money for the copper pipe than have to drink contaminated water. If you run the faucet in the kitchen, you can actually smell the water from where you stand.


Subject: Bad taste and smell and health concerns from PEX pipes

I truly regret installing PEX pipes in our house. Unfortunately, in our area the water causes pinhole leaks in copper pipes, so to prevent leaks and potential mold we had the house repiped with PEX. After two months, the water still smells and tastes bad from some faucets. I worry about the health effect of PEX, especially for my children. I'd like to know the concentrations of volatile organic compounds, but it's not the sort of thing in home test kits. Does our water have higher concentrations of MTBE or toluene etc. than is safe. I have daily headaches since we moved in with the new pipes and wonder if something in the water is causing it. I don't even want to shower in it.


Subject: Water quality testing

The house I bought has a well, and I had to replace plumbing and PEX seemed like the best alternative for me. I researched PEX and found that it was considered safe. I was more concerned with the quality of water in the aquifer my well accesses than the water safety coming through the PEX. Labs will test water, but there is a separate charge for each thing they test for and that quickly adds up. My local county health dept. tests water and it was much more economical. I paid about $120 for tests of lead, nitrates, nitrites and bacteria and the results came out fine. I still installed a whole house filter that cost about $350 and removes particles and reduces some contaminants (not all). Each region has its water quality issues -- I was concerned about environmental pollutants and fertilizer run-off. I recommend you contact your health dept. To see if they test water. I don't know why your water tastes or smells bad . . my water that runs through PEX is fine.


Subject: pex pipe

we just bought a new house plumbed with pex pipe, the taste and smell of the water is awful!!


Subject: That's normal for any new

That's normal for any new home. It will take a few days to a week and the water will clear out. It's because the water was sitting in the lines for so long. We noticed the same thing in our new home. It will happen with copper as well.


Subject: Quality of Water

Very interesting article. I'd really like to see more info about chemicals leaching into water. This is a big concern for me as I am building a house. I want to use what is best for my health, not my wallet.

Kelly Craig

Subject: Question "Facts"

Merely that an entity is a non-profit is no indicator of its reliability.

An associate wished to promote a hygiene product, so formed just such a corporation. He was, then, able to state his product was endorsed by the official sounding, dental related non-profit testing facility.

Of course, the test amounted to little more than, "[y]ep, other products like it say they work and I swished some around my mouth, so mine works too."

Add to the foregoing the fact a non-profit can make as much as any other business. It may have to pay most of it out for expenses, like hiring CEO's and paying them millions a year, so the words non-profit don't really mean much.


Subject: Photo of pex pipe

Funny, well, not so funny but one of the first things I read about PEX pipe is that it can be destroyed, (ie lifetime cut in half) by exposing it to the sun and here you have a photo of the hot water tubing sitting out in open daylight. Hope Matthew doesn't have some breakdown any time soon

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First - NOT full septic tank - if that was the case you would be getting backup of sewage into the lowest drains in the house, and possible very slow flushing or refusal to drain out of the bowl - the opposite of your case.

Second - I assume you are the owner. If a renter or on a lease, this type of problem may be the responsibility of your landlord, depending on the terms of your lease or rental agreement.

OK - two possible situations here - low water in BOWL, or low water in TANK. I am assuming your toilet flushes OK, with adequate water to clean out the bowl, and that it is a typical type toilet with a tank sitting on the back of the bowl. If this is not the case and it is a designer toilet or looks like those at public restrooms (no tank), then the BOWL answers still apply if it is initially refilling OK, but if not enough refill water coming in at all then call a plumber.

First, low water in the toilet BOWL case. If the water in the toilet BOWL is low after flushing, I see four likely causes, in order of most likelihood -

1) the fill valve is not putting enough water into the toilet bowl. If you take the top off the tank, you will see a small hose (typically black plastic) coming from the fill valve (a vertical mechanism, usually at left side of tank, that the incoming water tube or flex hose connects to the bottom of on the bottom side of the tank). While the tank is refilling after a flush, a steady but not large flow of water flows through this fill tube and down into a vertical pipe or tube (usually brass or plastic and about 3/4 inch diameter, which stands almost full height of tank). The small tube puts water into this pipe, from where it flows into and refills the toilet bowl. This is also the overflow tube, which keeps the tank from overflowing if the fill valve fails to shut off. If the fill valve has a problem or the fill tube has a blockage, it may not be letting enough water into the bowl. Also, check the tube is actually pointed down into the overflow tube - if the clip came loose, rusted away or broke, then it may just be filling the toilet tank rather than the bowl. Check that a steady flow (will not be a real foreceful jet) of water is flowing out of this tube into the overflow pipe while the toilet tank is refilling. You should also see the bowl filling up at this time. If it come in but does not fill high enough because it does not run long enough, some fill valves have an adjustment - check fill valve manufacturer website for instructions. Others just have to be replaced - doable if you are handy at home repairs (see web videos on how to do it), or call a plumber for probably about $150-200 to replace fill valve (have him replace the flapper valve at same time if you get this done).

2) there is something like a rag or string caught in the trap (the waste passage within the toilet body itself) which is slowly wicking the bowl water down the drain - would be solved by a good snaking. If this is the case, the bowl will fill fully after flushing, but then slowly (typically many minutes to hours) drain down to just filling the start of the oval or round drain passageway where the waste passage starts to curve up into the toilet body.

3) blocked sewer vent pipe (which vents sewer gas and lets air into the sewer system so when you flush the traps in drains and toilets and such do not get sucked dry by the vacumn caused by the exiting flow. If this is the problem, then several drains in your house may have the same problem, or drain slowly. When you flush, the water will drain totally down the pipe and almost all the water in the bowl and trap will go down the drain too, typically with a gurgling sound for a few seconds at the end as the air seal is broken in the trap, then a small amount of water will flow back from the trap into the bowl, leaving you with water in the entrance curve to the trap but nowhere near normal height in the bowl - maybe not even enough to fill the entrance of the drain passage.

4) a crack in the toilet, letting water gradually leak out of the bowl onto the floor or into the subfloor. If this has been going on for long at all you should see water on the floor, or water coming out in the ceiling downstairs, or in the basement or crawl space under the toilet.

Case 2 - the problem is low water in the toilet TANK - since this is a sudden problem, two likely causes:

1)  the float arm has corroded or the float setting has moved. Look in tank for any broken part. You may have a black ball on the end of a metal or plastic arm connected to the fill valve (which is the part, normally at the left side of the tank, that the flexible or copper tubing comes into at the bottom of the tank), or it may be a sliding cylindrical float that slides up and down on the fill valve (typically all plastic) - see if it is broken or loose or alll corroded up (for the arm type). When you flush, this float hangs down (if lever type) or slides down the fill valve (cylinder type), opening the fill valve so fresh water comes in to fill the tank and bowl. As the tank fills it lifts this float, till at the proper elevation the bouyancy of the float shuts off the fill valve. If the setting on this float has changed then it will either cause the toilet to "run" continually because it is trying to overfill the tank (float shuts off at too high a level, so water is continuously flowing down into the overflow tube and into the bowl); or it will shut off too soon, causing only a partial tank fill. There are adjustments to adjust the float shutoff setting - typically an adjustment xxxx on the arm-type, and a slider stop clip on a small rod for the sliding type. See web videos on how to adjust this, or call a plumber.

2) your flapper valve (in bottom of tank, the part a chain or cord or rod connects to the flush handle, which opens it when you flush the toilet, leaks. If it leaks AND the fill valve is working, the tank level drops till the fill valve opens, then the tank refills. This repeats at intervals, with the tank refilling periodically even though it has not been flushed. May need new flapper valve or just a good wiping of the sealing surface to remove grit that is causin it to leak. If this is the problem you will have a slight flow of water into the bowl continually, and will probably see a slight ripple in the toilet bowl.

3) water is leaking out of the fittings or bolt holes on the bottom of the tank. If this is happening enough to make you notice low takn water level, the tank will refill periodically the same as if the flapper valve is leaking, plus you will have water on the floor and dripping off the bottom of the tank.


Fill valve and flapper valves each cost around $15 if you do it yourself (you can buy just replacement flapper for less if that is the problem and the matching seal is good, but that is rarely the case). A plumber call to replace both probably $150-200, ASSUMING your water shutoff valve (at the wall, under the tank, with a flex or copper tube coming fromit up to the toilet tank) will work.. If it will not shut off the flow of water, then add another $50-150 to replace that, depending on how it is plumbed and whether he has to cut into the wall to replace it (rarely required). If you do go and have a plumber do it, have both the fill valve and flapper valve (and flush handle, if aluminum or brass and corroded) replaced at the same time, as all tend to go out with age - every 10 years or so. You don't want to have to call the plumber to replace another part in just a year or two.


From the sounds of it, you have a clog between the floor drain and the connection to the city sewer (unless you have a septic tank).  The lower flow rates of sinks / showers / dishwashers probable don't cause a backup like the washing machine does.  A couple of suggestions.

1.  Snake the drain line with a spade tip snake, twisting the snake as you advance it.  This should clear the partial blockage.

 2.  If feasable, have your washing machine discharge into a utility sink and put a strainer on the drain to catch the clothing fibre (fibres and grease from the sink probably made the clog in the first place not to mention a garbage disposal).

3.  Replace your floor drain with one that has a backflow preventer (looks like there is a ping pong ball in it).

 Good Luck


Sounds reasonable considering the concrete. 

However replacing the flange yourself is an easy job. 

I recently used the Culwell Flange to replace the flanges in all of my bathrooms. 

It seals to the floor. 

Has anyone used this flange?

I found it on Amazon, but they have a website

It is not uncommon for a plumber to have to go get the parts necessary to repair and complete the job.  It is very hard to determine what the problem is over the phone and it is not until the repair process begins that the parts needed to resolve the problem is discovered.  It may also depend on if the plumber is using hourly rates or per job rates.  I would hope the time to get the parts would be minimal and the charge would be as well!