With sunscreen becoming a daily essential in skincare, there is a rising concern about whether some UV filters can be absorbed into the bloodstream. This doesn’t automatically mean sunscreen is unsafe, but it does raise an important question: which filters stay mostly on the skin, and which ones show measurable systemic exposure? This article explains what the FDA’s absorption threshold really means, what the Matta studies revealed about older UV filters, and why bemotrizinol stands out with data showing minimal absorption.

Let's look at the chart below,

The red line marks the FDA's safety threshold: 0.5 ng/mL. If a sunscreen ingredient appears in your bloodstream above this level, the FDA requires further safety testing before it can be considered safe. This isn't a 'danger' line. It's a 'we need more data' line.

Now look at what the legacy UV filters did.

The Matta Studies Changed the Conversation

In 2019 and 2020, Matta et al. published two landmark studies in JAMA. They applied sunscreen to volunteers under maximal use conditions - the way sunscreen labels tell you to use it and measured plasma concentrations over time.

Every single legacy chemical filter tested exceeded the threshold. Most by double digits. One by triple. These aren't rare ingredients. They are in sunscreens sold worldwide, applied daily by millions of people.

The Problem With 'Grandfathered' Filters

Here's what most people don't realise: these UV filters were never tested for absorption when they were first approved. They were grandfathered into regulations decades ago, based on assumptions that topical ingredients stay topical.

The Matta data proved otherwise. To be clear - exceeding the threshold doesn't automatically mean harm. But it does mean we don't have the safety data to rule harm out. For ingredients applied daily, often for years, that's a gap worth closing.

Bemotrizinol: The Exception

In 2023, D'Ruiz et al. tested bemotrizinol using the same MUsT (Maximum Usage Trial) protocol. Same rigorous methodology. Same real world application conditions.

Bemotrizinol is now the first and currently the only chemical UV filter to meet the FDA's updated absorption requirements. It's under consideration for GRASE (Generally Recognized As Safe and Effective) status, a milestone no chemical filter has achieved since 1999.

This isn't an accident of chemistry. Bemotrizinol's molecular weight is 627 g/mol - significantly larger than oxybenzone at 228 g/mol. Larger molecules have more difficulty crossing the skin barrier. The low absorption was designed in.

What This Means for Daily Sunscreen Users

If you are using sunscreen the way you should - daily, generously, reapplied, then the UV filters in your product matter. The Matta studies proved that older filters like oxybenzone entered the bloodstream even with one single application.

The chart shows the reality: most chemical filters on the market today exceed the FDA's threshold for unstudied systemic exposure. One filter doesn't.

That's why SAFESCREEN Nexgen is built around bemotrizinol. Not because it's new. But because it's been approved in Europe and Asia since 2000 and now the only chemical filter with MUsT data proving it stays where it belongs - on the skin.