Forever Chemicals in My Blood: What I Learned Testing for PFAS and Microplastics

I recently took the plunge and tested my blood for microplastics using Bryan Johnson’s Blueprint test. The results came back: 17 particles detected, all under 10 microns in size. My initial reaction? Skepticism about what this actually means.

After digging deep into the science, I’ve concluded that PFAS testing is genuinely actionable while microplastics testing is mostly an expensive data point—at least for now. Here’s what I learned, and how you can get tested yourself for less.

My Blueprint Microplastics Results: The Hard Truth

My Test Results (January 8, 2025)

| Total Particles | 17 | | Size Distribution | 100% under 10µm (smallest, most concerning size) | | Concentration | 170 particles/ml | | Population Percentile | Better than 44%, worse than 26% |

What This Actually Tells Me

Virtually nothing actionable. Here’s why:

1. No clinical thresholds exist. Unlike PFAS, where ≥20 ng/mL triggers follow-up care, there’s no established “safe” or “dangerous” level of microplastics.
2. No polymer identification. The test doesn’t tell me what kind of plastic. Without knowing the type, I can’t identify my exposure source.
3. Self-selected comparison population. I’m being compared to people who paid $199 for a Bryan Johnson longevity test—biohackers, not a representative sample.
4. High day-to-day variability. Blood microplastics fluctuate based on recent meals, environment, and hydration.

The Honest Assessment

I paid $199 for a number without clinical meaning, compared to an irrelevant population, with no actionable source identification. It’s a curiosity purchase, not a health optimization tool.

The Science: What’s Actually Proven to Harm Humans

PFAS (“Forever Chemicals”) — Strong Evidence Base

The National Academies of Sciences established strength-of-evidence classifications in 2022:

Key stat: 98% of Americans have measurable PFAS in their blood.