Lead in plumbing.

The water leaving your treatment plant is almost certainly fine. The pipes, solder, and fittings between the street and your tap are where the lead actually enters your glass — and most of it is invisible until you test for it.

Where lead reaches your tap.

An estimated 9.2 million U.S. homes still have a lead service line — the pipe that runs from the water main in the street into the house. It is the single largest source of lead in residential drinking water, and most owners have no idea it is there.

Lead solder was banned for drinking-water plumbing in the United States in 1986. Houses built or repiped before then very likely have lead solder at every joint of their copper pipe. Each joint is a small lead deposit sitting directly in the water.

Even “lead-free” brass faucets manufactured before 2014 could legally contain up to 8% lead by weight. Lead leaches into water any time the water sits still in the pipes — which is why first-draw water in the morning is consistently the most contaminated sample in any given home.

Where to look in your house.

If your home is pre-1986, assume lead is somewhere in the system until you prove otherwise. The high-risk targets:

• Solder joints on copper pipes — the silvery beads where two copper pipes meet. Pre-1986 solder is roughly half lead by weight.
• Brass faucets and valves — especially anything installed before 2014. Up to 8% lead was legal under the old “lead-free” standard.
• Galvanized fittings — old galvanized steel can absorb lead from upstream pipes and release it for decades, even after the lead source is removed.
• Lead service lines — look near your water meter for a dull-gray pipe with a curved gooseneck where it enters the house. Scratch it lightly: lead is soft and shines silver. Copper is harder and shines orange.
• Hose bibs and outdoor spigots — commonly cast brass with measurable lead content.

How to test pipes and fittings.

Plumbing testing has two parts: testing the metal itself, and testing the water that comes out of it. Both matter, and they answer different questions.

1. Expose the joint. Find a solder joint on an accessible run of copper pipe (under a sink, in a basement, near the water heater). Wipe it clean of dust and oxidation.
2. Drip FluoroSpec directly on the solder. One drop on the silvery bead between the pipes. The reagent reacts with lead on contact — you are testing the metal of the joint itself, not the water.
3. Read the result against the color chart. A positive reaction means that joint is leaching lead into every gallon of water that passes through it.
4. Repeat on brass faucets, valves, and fittings. Each fixture is a separate lead source. One clean joint does not mean the next one is clean.
5. For water testing, use the first-draw protocol. Collect water that has sat motionless in the pipes for at least 6 hours — first thing in the morning is ideal. The EPA action level is 15 ppb (parts per billion) at the tap. For ongoing filtration, use an NSF 53 or NSF 58 certified filter — the only standards specifically tested to remove lead.

Testing the pipe tells you the source. Testing the water tells you the dose. Do both.

Test your plumbing.

The Full Kit gives you enough FluoroSpec to test every accessible solder joint, brass fitting, and service-line entry point in your house in one afternoon — no lab, no waiting.