@Girlparts Can somebody get the the original paper and report on what concentration they were using. Whenever I've compared lab results with environmental measurements, the labs are using >1,000,000-fold higher concentrations of particles to get a response. It's never immediately obvious because the two kinds of studies typically use different units.

The other question I have is the particle size. Their largest particles in the study are 1µm. That's generally the smallest that I've been able to find reported in environmental measures. Either it's just not possible to detect unlabelled particles smaller than that (which as an analytical chemist, I doubt), or particles at that size range break down quite quickly do the exponentially increasing surface area/volume ratio. If anyone has links to papers that look that far down the size scale, I'd appreciate them.