Di(2-ethylhexyl) phthalate
DEHP·Affects liver, reproductive
The most widely used plasticizer in flexible PVC. DEHP leaches from plastic pipes and consumer products into drinking water and is a documented endocrine disruptor.
DEHP
EPA limit
0.006 mg/L (MCL)
Most at risk
Infants, pregnant women, people on PVC-piped supplies
Found in
City water · Well water · Industrial areas
AquaOx filters
YesActivated coconut shell carbon
What it does to you
Health effects
DEHP is classified by the EPA as a probable human carcinogen based on liver tumor formation in animal studies. The NTP (National Toxicology Program) lists it as reasonably anticipated to be a human carcinogen. The liver and the reproductive system are the primary target organs for chronic exposure.
DEHP is one of the better-studied endocrine disruptors in drinking water. It interferes with testosterone synthesis and has been associated with reduced sperm quality, altered male reproductive development, and changes in pubertal timing. Prenatal exposure is the highest-concern window. The European Union, FDA, and CPSC have all restricted DEHP in children's products and medical devices used for neonates.
DEHP also affects thyroid function and contributes to insulin resistance in long-term high-exposure populations. The MCL of 0.006 mg/L is roughly 70 times lower than the DEHA limit precisely because the toxicity is more pronounced.
Where it comes from
How it gets into your water
DEHP is the dominant plasticizer in flexible PVC products: water pipes, vinyl tubing, IV bags, blood-storage bags, shower curtains, flooring, and food packaging. It is not chemically bonded to the plastic, so it slowly migrates out into anything the plastic touches: water, food, blood, indoor air.
In drinking water specifically, DEHP enters through leaching from PVC distribution pipes and home plumbing, particularly when water sits stagnant or is heated. Industrial discharge from plastic-manufacturing facilities and landfill leachate from plastic waste are secondary sources.
Flexible PVC water pipes
Primary leaching source in homes
Plastics manufacturing
Discharge to surface + groundwater
Hot water lines
Heat accelerates plasticizer migration
Landfill leachate
Plastic-waste breakdown
Find out for yourself
Is it in your water?
Utilities are required to test for DEHP and report it in the Consumer Confidence Report. Most large systems run below the 0.006 mg/L limit, but DEHP levels can be detectable in homes with extensive PVC plumbing or with hot-water lines that run through PEX or vinyl tubing.
Well-water households with plastic well casings, polymer-lined pressure tanks, or vinyl tubing in the pump system should request a DEHP test from an EPA-certified lab if there's any concern. Standard well-water panels typically include phthalates as a group test.
The fix
How AquaOx filters it
DEHP is a large, non-polar organic molecule, and activated carbon adsorbs it well. Both the coconut shell carbon and Centaur catalytic carbon stages in The AquaOx capture DEHP as water passes through the filter bed.
Whole-house treatment is the right model for DEHP because it leaches throughout the home plumbing, not just at the kitchen sink. Filtering DEHP at the point of entry also reduces dermal and inhalation exposure during showers, both of which contribute to total daily intake for flexible-PVC-plumbed homes.