Introducing version 2 of the microplastic exposure calculator

When we launched the first version of the Exposure Calculator, the goal was simple: take a sprawling scientific literature and turn it into something you could actually use in five minutes.

A score. A few honest insights. A starting point.

Version 2 keeps that spirit. It just covers more of the picture.

What's new

More of the exposure routes that actually matter. Version 1 was a first pass. It covered some of the most visible and best supported sources, but it did not yet capture enough of the everyday routes shaping exposure. Version 2 expands that scope. We added factors such as plastic mesh tea bags, cutting boards, nonstick cookware, laundering synthetic fabrics, hot beverage cups, infant formula preparation, dairy, cooking oils, commute type, and more. Version 1 used 19 questions across 5 categories. Version 2 uses 35 questions across 6.

More geographic coverage. Version 1 treated geography more simply. Version 2 builds out a much broader country layer so the calculator can reflect more of the background environmental burden people live inside, not just the habits they report directly. That makes the tool more comprehensive without pretending geography explains everything.

Finer distinctions where they count. Some of the biggest improvements are not new topics, but better distinctions inside existing ones. Bottled water is no longer treated as one category. The calculator now separates single use PET from glass and stainless steel, because the exposure literature does not put them in the same league. Seafood now separates shellfish from finfish for the same reason.

Pathway tagging. Every factor is now tagged as ingestion, inhalation, or both. That gives the calculator a better way to describe not just how much may be contributing to your score, but how that exposure is likely reaching you in the first place. It also creates a foundation for future versions to show which route appears to be doing the most work in a given profile.

Particle estimates. Where the literature gives us a defensible particles per day estimate, the calculator now shows an estimated daily particle intake alongside the score. It is still a rough order of magnitude figure, not a biological measurement. But it makes the result more concrete.

Visible evidence strength. Every factor now carries an evidence tag: strong, moderate, emerging, or modeled. We want users to be able to see which parts of the score rest on better established findings and which parts still rely on earlier or more inferential evidence. That kind of transparency matters more than making the output look cleaner than it really is.

Support for children and infants. Version 2 also adapts the questionnaire for younger age groups. That includes infant formula questions, age specific weighting, and hiding questions that are not relevant for very young children. That change matters because exposure patterns are not the same across life stages.

What stayed the same

The calculator is still a research backed estimate of relative exposure, not a medical test. It is still free. It still runs in about five minutes. And it still starts from a baseline of 35, reflecting the reality that even someone actively trying to reduce plastic contact still lives inside a world where microplastics are already broadly present in food, water, and air.

That part of the story has not changed.

Why we updated it

This update is less about a sudden shift in the science and more about building a fuller tool.

Version 1 was intentionally limited. It was designed as a transparent first pass. But it did not yet account for enough countries, enough routes, or enough of the ordinary exposure sources that appear to shape real life patterns. Version 2 is our attempt to make the model more comprehensive while keeping the same discipline about uncertainty and evidence quality.

The goal is still not false precision. It is a better estimate. More complete where the literature supports it. More transparent where it does not.

Methodology

The full Version 2 methodology, including the question set, factor weights, pathway tags, evidence levels, and scoring logic, is published alongside this update. If you want to see exactly how the score is built, it is all there.