Lead
Old paint dust. Pipes. Some work. It steals calcium’s seat in the nerve. That’s not a metaphor. Signaling gets sloppy. In children the documented cost is attention, learning, and IQ. In adults it’s mood, memory, blood pressure, and a neuropathy if the dose was high. The marrow misses heme. You don’t need a conspiracy to explain a tired, irritable brain. You need a blood lead.
Mercury
Three metals wearing one name. Vapor (the job, not a rumor) goes lung to brain: tremor, a short fuse, the old word was erethism. Inorganic salts hit the kidney. Methylmercury rides in on certain fish, binds sulfur, crosses into the developing brain and the unborn. Minamata was real. A tuna sandwich is not Minamata. Don’t flatten those into one sentence.
Arsenic
Private wells. Some rice, because the plant drinks the water it stands in. The classic wreck is skin, bladder, lung, and the nerves in the hands and feet. Children on contaminated water also show up worse on cognition. The brain is not the headline. It is not spared either.
Aluminum
Not the same club. Dialysis proved a wrecked brain when a large IV load met kidneys that could not clear it. Pans, deodorant, and a normal diet are not that case. The Alzheimer’s claim has been around for decades and it is not settled. Don’t say the frying pan did it.
