Comparison · Updated April 2026

Same chemistry. Different bottle. Very different price.

FluoroSpec and Lumetallix both detect lead the same way: methylammonium bromide reagent forms perovskite quantum dots that fluoresce green under 365 nm UV. The chemistry is published, peer-reviewed, and not proprietary to either of us. What differs is bottle size, price per ml, US EPA registration, the test count per kit, and a couple of things that should be on the record about where this chemistry actually came from.

By Eric Ritter, founder of Fluoro-Spec Inc. Reviewed against publicly listed Lumetallix product configurations and the published peer-reviewed literature.

The bottle size, in your hand

Photographed on the same surface, same lighting, same camera. Lumetallix on the left in each frame. FluoroSpec on the right.

What the numbers actually look like

Both kits use the same MABr-in-isopropanol reagent and both kits include a 365 nm UV flashlight. The math is volume × cost × tests-per-bottle. A FluoroSpec Full Kit gets you about 3.2× the total reagent and roughly 8× more total tests than the Lumetallix two-product lineup, for less money.

The Spray Extender Ring · why your spray test count is 3× higher

Every FluoroSpec kit ships with a free Spray Extender Ring. Slide it onto the spray-bottle nozzle and it modulates the spray volume per pump from a wide ~50 µL dose down to a focused ~17 µL dose. Same surface coverage, less reagent per shot. That moves the spray bottle from 170 tests baseline to roughly 500 tests.

The drip bottle's 3,600-test count comes from the same idea applied to the drip-tip applicator: a calibrated drop is much smaller than a classical eye-dropper drop, so the bottle goes a lot further. Neither of these numbers comes from a thicker reagent or a more concentrated formulation. They come from controlling how much fluid leaves the bottle per actuation.

The Lumetallix dropper-cap issue

One ergonomic gotcha worth flagging if you have or are considering the Lumetallix kit. The dropper insert can get lodged inside the cap when you remove it. It is not a defect of the chemistry or the reagent, but it is a real workflow snag. You can usually retrieve the insert with tweezers, push it back into the bottle neck, and continue testing.

Face-off · same surface, both products

The honest part of the comparison: both products use the same MABr-in-isopropanol chemistry, so on most surfaces both will detect lead. But the spread between "barely visible" and "obvious glow" matters a lot at the threshold of detection. We ran two head-to-head tests, paint and glass, with the bottles in the frame so you can see exactly what each one shows.

Test 01 · 800 ppm lead paint

This is a deliberately lead-doped paint sample, measured at 800 ppm Pb on XRF. Both reagents were applied to the same patch under identical 365 nm UV. Lumetallix struggled to register the paint clearly. FluoroSpec lit it up. Lumetallix's own customer-comment thread (visible in the bottom of the clip) acknowledges their reagent caps out at roughly 200 ppm sensitivity, not 500 ppm as their original spec sheet suggested.

Test 02 · painted glass

Vintage gold-leaf decorated glassware, the kind you find at every estate sale in New England. Lumetallix gives a faint signal. FluoroSpec gives the unambiguous green that you do not need to squint at.

Where this chemistry actually came from

Both products are consumer applications of published, peer-reviewed academic chemistry that was not invented by either of us. The relevant prior art:

Yan et al. demonstrated that methylammonium lead bromide is a sensitive fluorescent signal for lead contamination both in solution and on paper substrates. They showed the green emission characteristic at the wavelengths every consumer kit on the market today depends on.

Wang et al. published quantitative limits-of-detection for MAPbBr₃ formed in situ from lead contact, demonstrating that even roughly 1 ng/mm² of lead is comfortably visible once converted to perovskite under standard 365 nm UV. That is the sub-ppm sensitivity that makes any consumer-grade fluorescence test viable.

Holtus et al. (the same research group that founded Lumetallix) earlier published the sand-dollar paper, which described the conversion-to-perovskite method on biological calcium-carbonate substrates. The conversion technique they later commercialized as a consumer lead test grew directly out of that earlier work, not from a separate invention. The transition from "sand-dollar surfaces" to "lead-contaminated surfaces" was a substrate change, not a chemistry change.

Timeline · public chemistry → consumer products

Source · Yan et al., MAPbBr₃ fluorescence as a lead-contamination signal in solution and on paper · Wang et al., quantitative MAPbBr₃ sensitivity at ~1 ng/mm² limits of detection · Holtus et al. (the Lumetallix research group), sand-dollar perovskite-conversion paper, the methodological precursor to the consumer-product version. Helmbrecht 2023 perovskite-fluorescence open-access paper. None of these are proprietary to either FluoroSpec or Lumetallix.

About the Lumetallix patent application

The Lumetallix patent application claims the use of MABr-in-isopropanol for detecting lead on "painted surfaces, metal, glass, and plastic." The chemistry of MAPbBr₃ formation is not actually substrate-specific in the way that framing implies, and the application has some practical issues.

MAPbBr₃ fluoresces wherever it forms in even trace quantities. The reaction depends on accessible lead ions, an alcohol environment for the methylammonium bromide, and a 365 nm photon to excite the resulting perovskite quantum dots. The substrate underneath the lead is not the variable controlling whether the chemistry works.

The substrate-specific framing in the application breaks down on inspection:

• On metal and glass, the demonstrated reaction worked notably less well than on paint, because both substrates expose far less surface lead than a painted ceramic or metal-bearing pigment surface. That is a property of where the lead actually is, not of the chemistry.
• The paint sample used in the application contained over 60% lead compound, which is an extreme test case far above what any modern consumer encounters. Real-world leaded paint runs 0.1% to roughly 5%. A working demonstration on a 60%-lead paint chip is not representative.
• Plastic was claimed but never demonstrated as testable in the public application materials.

The result is a patent application whose claims read as overbroad relative to the underlying chemistry, and whose demonstrated examples do not span the substrate range the application asserts. The chemistry works the way the chemistry works. The patent claims do not change that.

What FluoroSpec actually improves

The honest summary of where this product is better, and where it is the same:

Better: more reagent per bottle (3× drip, 3.3× spray), lower price per ml (~5× cheaper drip), more total tests per kit (~8× more), free Spray Extender Ring that triples the spray test count, brighter included 365 nm UV flashlight, a US EPA TSCA Low Volume Exemption (L-25-0206) on file, a 98-page Lead Framework Book on what to do after a positive result, and a 2026-published 4-year database of 47,802 California AB 899 baby food test results plus four other lead-test data sources.

The same: the chemistry. Both products use methylammonium bromide in isopropanol. Both detect lead via MAPbBr₃ perovskite formation. Both fluoresce green at ~530 nm under 365 nm UV. Neither of us invented the underlying reaction.

Different in framing: the entire information package surrounding the test. FluoroSpec ships with a curriculum, a database, a calculator, a community feed, and a direct line to the chemist who built it. Lumetallix ships with a bottle.

Why I built this

I started everythinglead.org as a vehicle to learn every last thing about lead, and it worked. Along the way I learned more than I expected to.

I learned that lead has contaminated the nervous systems of billions of adults still alive today. The cardiovascular wave is documented, the dementia wave is starting, and the cognitive wave is the quietest one of all. I learned that a population dosed with neurotoxin during development behaves measurably differently than a population that was not. The peer-reviewed literature on this is too consistent to ignore. Reyes 2007. Aizer & Currie 2014. Lanphear 2018. Wehby 2021. Wang et al. 2026.

I built FluoroSpec because the existing consumer market for lead detection was missing a kit with the right form factor, the right volume, the right price, the right regulatory clearance, and most of all the right context around the test. Tests without context produce panic or denial. Context without tests produces inaction. The kit and the curriculum together are the actual product.

I improved on this test on every axis I can measure. More tests per bottle. Lower price per ml. Better sensitivity per actuation. Brighter included light. A real US EPA chemical-substance registration. A book. A database. A calculator. A community. A direct contact line to the chemist. The package is, virtually, the entire package.

There is not much else to say on the subject of which kit is the better consumer product.