Microplastics in Arizona Tap Water: What's There, How to Remove Them

What Microplastics Are

Microplastics are plastic particles smaller than 5 millimeters. They reach drinking water through three primary routes: (1) plastic infrastructure shedding fibers as water flows through it, (2) airborne plastic dust settling into open reservoirs and treatment basins, and (3) breakdown of larger plastic debris in rivers and lakes. The smallest fraction, called nanoplastics, measures under 1 micrometer (µm). For context, a human hair is about 70 µm wide. Most municipal water filtration was designed before microplastics were a known concern, so it captures sediment and particles down to roughly 5 to 10 µm but lets nanoplastics pass through.

The Arizona Picture

Arizona's drinking water comes from three main sources: Colorado River water delivered through the Central Arizona Project (CAP), Salt and Verde River water managed by the Salt River Project (SRP), and groundwater pumped from local aquifers. Each carries some level of microplastic burden. The Colorado River, in particular, picks up plastic pollution from upstream Las Vegas and downstream urban areas. CAP water travels 336 miles from Lake Havasu through open canals exposed to airborne plastic dust before reaching Phoenix-area treatment plants.

Arizona utilities are not required to test for or report microplastics. There are no Phoenix, Mesa, or Tucson Consumer Confidence Reports listing microplastic concentrations because no MCL exists to enforce. What we know comes from independent academic studies and the Orb Media journalism investigation, which found microplastic fibers in 94 percent of US tap water samples on average. Phoenix-area homeowners should assume some microplastic presence is consistent with the national pattern. Your annual CCR will not list microplastics for this reason.

Where Microplastics Come From in Arizona Water

Health Concerns

The research on chronic health effects from drinking microplastics is still developing, but recent peer-reviewed studies have detected microplastic particles in human blood (Leslie et al., 2022), lungs (Jenner et al., 2022), placenta (Ragusa et al., 2021), and stool. The World Health Organization noted in its 2019 review that long-term health data is insufficient but recommended that consumers reduce exposure where possible.

The two specific concerns scientists raise most often are bioaccumulation (small particles can lodge in tissue and persist for years) and adsorption (microplastics attract and carry other contaminants like heavy metals and PFAS chemicals into the body). Children and pregnant women are typically advised to be more cautious because their developing systems are more sensitive to inflammatory and endocrine-disrupting compounds.

Which Filtration Methods Actually Work

Reverse Osmosis (RO)

Reverse osmosis pushes water through a semi-permeable membrane with pores around 0.0001 µm, which captures essentially all microplastic and nanoplastic particles. RO is the gold standard for drinking water purification but is typically installed at a single tap (usually the kitchen sink) rather than the whole home because it works slowly and produces some wastewater. Most Arizona homes that prioritize microplastic removal pair a whole-home softener and catalytic carbon stage with an under-sink RO unit.

Sub-Micron Catalytic Carbon Block

Carbon block filters rated at 0.5 to 1 micron capture larger microplastic fibers and particles. They are not as thorough as RO for nanoplastics, but they treat the entire home and they also remove chloramine, disinfection byproducts, and chlorine taste. The Aquafeel dual-tank system uses catalytic carbon in one of its stages, providing measurable microplastic reduction across every faucet. Pair with under-sink RO at the kitchen for maximum drinking water purity.

Sediment Filters Alone Are Not Enough

Standard sediment cartridges typically rate at 5 to 50 microns. They capture rust flakes, sand, and visible particles but pass through almost all microplastics. If your only treatment is a sediment cartridge at your main line, microplastic protection is minimal. Sediment filters are still useful as the first stage of a multi-stage system because they extend the life of finer downstream filters.

Boiling Does Not Remove Microplastics

Boiling water concentrates microplastics rather than removing them. The plastic does not break down at boiling temperatures, and as water evaporates, particle concentration in what remains actually rises. Boil-only protocols are appropriate for microbial contamination, not microplastic contamination.

Bottled Water Is Worse, Not Better

The 2024 Columbia University study published in PNAS analyzed three popular bottled water brands and found an average of 240,000 plastic particles per liter, with 90 percent of those classified as nanoplastics. Most of the contamination came from the bottle itself, especially after exposure to heat during shipping or storage. A properly sized home filtration system produces drinking water with significantly fewer microplastic particles than bottled water at a fraction of the lifetime cost.

What an Aquafeel Solutions Arizona Free Test Will Show You

Our free 15-minute in-home water test does not directly count microplastic particles (no consumer-grade equipment can do that without lab analysis). But the test does reveal three indirect indicators: total dissolved solids (TDS), particle clarity through visual comparison, and the presence of upstream contaminants like chloramine and disinfection byproducts that often correlate with microplastic exposure pathways. We then walk you through filtration options sized for your specific water profile - including under-sink RO if microplastic concern is your primary motivator. Schedule your free test to see exactly where your home stands.