Microplastics
MP·Affects liver, reproductive, brain
Plastic fragments smaller than 5 mm that are now detected in nearly every drinking water supply tested worldwide. Federally unregulated; California became the first US state to set a standard.
MP
EPA limit
No federal MCL (California has the first US state standard)
Most at risk
Infants, young children, regular bottled-water drinkers
Found in
City water · Well water · Industrial areas
AquaOx filters
YesMulti-stage sediment + carbon filtration
What it does to you
Health effects
Microplastics are plastic particles between 1 micrometer and 5 millimeters across; nanoplastics are the even smaller fraction below 1 micrometer. They have been measured in human blood, lung tissue, placenta, breast milk, and stool. The research on long-term health effects is still emerging.
Documented and suspected concerns include inflammation in tissue where particles deposit, disruption of gut microbiota, oxidative stress, and endocrine effects from plasticizer additives (bisphenols, phthalates) that leach from the particles. Animal studies show particle migration from the gut into the bloodstream and accumulation in the liver and brain.
The World Health Organization's 2019 review concluded that data was insufficient to fully assess risk but flagged the particles, the plastic additives, and the biofilms that grow on particle surfaces as three distinct exposure concerns that warrant continued study.
Where it comes from
How it gets into your water
Microplastics enter water from two main routes. First, fragmentation: larger plastic waste (bottles, packaging, fishing gear, tire wear) breaks down in the environment under UV light and physical abrasion. Second, direct release: synthetic textile fibers shed in laundry wastewater, microbeads from older personal-care products, and pellet spills from plastics manufacturing.
Once in waterways, particles travel everywhere. They have been measured in remote mountain rainwater, in Arctic ice, and in deep-ocean sediment. Drinking-water exposure happens both before and after treatment: source water carries particles in, and plastic pipes, fittings, and storage tanks add more downstream of the treatment plant.
Bottled water is consistently measured at higher microplastic concentrations than tap water, largely from the bottle itself and the cap.
Plastic distribution pipes
PVC, PEX, polyethylene mains and home plumbing
Synthetic textile laundry
Polyester and nylon fibers in wastewater
Tire and road wear
Stormwater runoff into surface water
Bottled water packaging
PET bottles shed more particles than tap
Find out for yourself
Is it in your water?
Almost certainly yes. Independent studies have detected microplastics in the overwhelming majority of US tap-water samples tested. There is no federal monitoring requirement, so utilities do not test or report microplastics in their Consumer Confidence Report (CCR).
California's State Water Resources Control Board adopted the first US drinking water standard for microplastics, with monitoring rolled out in phases starting in 2024. The EPA continues to fund microplastics research but has not proposed a federal MCL.
If you want a baseline for your own water, a few specialized commercial labs offer microplastic count and size-distribution testing on submitted samples, typically using vibrational spectroscopy or fluorescence microscopy.
The fix
How AquaOx filters it
The AquaOx filters microplastics primarily at the sediment-filtration stages. Filter-AG and garnet physically strain particles down to the filtration micron rating of the bed, and the activated carbon layer captures additional particles in the size range that fits between its pores.
Independent testing on multi-stage carbon and sediment systems shows high reduction for microplastics 1 micrometer and larger, the bulk of what is typically measured in tap water. Nanoplastics below 1 micrometer can pass through carbon; for those, reverse osmosis with its sub-nanometer pore size is the more thorough barrier.
Because plastic pipes themselves continue to shed particles, the most reliable point of filtration is at or near the point of use. The AquaOx whole-house system handles particles upstream of your plumbing, and pairing it with the under-sink RO at the kitchen tap captures nanoplastics in the water you drink and cook with.