What We Have Learned So Far

For the past several months, I have been trying to answer a difficult question: How can we test water for extremely small plastic particles in a meaningful and reliable way?

My goal was to find a process that could identify particles ranging from about 5 nanometers to 10 microns. That is a very wide range for a single testing method. After speaking with laboratories around the world and exploring different options for nearly five months, we finally found a possible approach close to home at UC San Diego.

Finding a Possible Testing Process

When we first began this work, I hoped we could find one test that would cover the full particle range. We quickly learned how difficult that would be.

Different instruments are designed to measure different characteristics and particle sizes. A method that works well for one part of the range may not work for another. Finding tiny particles is only part of the challenge. We also need to determine what those particles are made of.

The opportunity to test at UCSD felt like real progress. After months of research and conversations, we could finally bring water samples into a laboratory and begin learning through hands-on testing.

Our First Testing Session at UCSD

During our first session, we used four sophisticated pieces of equipment. The instruments helped us examine particle size and distribution, along with the chemical and elemental composition of the samples.

It was fascinating to see what each instrument could do and how the different methods might fit together. We also built relationships within the laboratory and gained a much better understanding of how future testing should be structured.

The results, however, were inconclusive.

That was not the outcome we hoped for, but the day was still valuable. It showed us where the testing process becomes complicated and what we need to change before the next round.

Why the Testing Was So Difficult

One of our biggest lessons involved the difference between particles and dissolved solids.

There was very little particulate matter in the samples compared with the amount of dissolved material. Dissolved solids move through the water as ions, and their signal can be much stronger than the signal from the small number of particles we are trying to study.

This makes it difficult to get a clean reading of the particles alone. Before we can confidently identify tiny plastic particles, we need a better way to separate them from the dissolved material or account for that material during testing.

This is now one of the main questions guiding our work.

Narrowing the Focus

The first testing session also convinced me to reduce the number of water types we examine at one time.

For the next stage, I plan to focus mainly on reverse osmosis water. Based on what we have learned so far, that is the water I am most interested in drinking and understanding more clearly.

I would also like to test selected waters sold in glass bottles. I have felt more comfortable with some of those options, but a feeling is not evidence. I want to see what careful testing tells us.

Bottled water may be more complicated to evaluate, so it may need a separate testing process or additional preparation.

Where We Stand Today

We do not have a definitive result yet. We have not confirmed that one method can identify plastic particles across the full range from 5 nanometers to 10 microns.

What we do have is a much clearer picture of the problem.

We now understand more about the equipment, the sample preparation challenges, the effect of dissolved solids, and the questions we need to answer before testing again. We have also started building relationships with people who can help us continue this work.

An inconclusive result can feel frustrating, but it is still part of honest scientific testing. The first session helped us move from a broad idea to a more focused plan.

What Comes Next

Our next step is to refine the testing process and concentrate on a smaller group of water samples. We will continue exploring how to isolate the particles we want to study and how to distinguish them from everything else in the water.

As the work continues, we will share what we learn, including the challenges and the results that do not provide an immediate answer.

We are still early in this process, but every testing session brings us closer to understanding what can be measured, what the current limitations are, and how we can make better decisions about the water we drink.

Check out the full length vlog here: