1.2What asbestos actually is

Asbestos is a family of natural minerals. They sit in rock seams and split into fibres so fine you can’t see them. Those fibres are strong, fireproof, cheap, and they don’t rot. For most of the 20th century, that combination made asbestos the most useful building material on earth.

The same properties make it carcinogenic. When asbestos is disturbed, those microscopic fibres become airborne. Breathe them in, and the body can’t break them down. Most are coughed back out. Some lodge in the lining of the lung or work their way to the lining of the abdomen, and stay there for decades. Around them, slowly, the body’s response goes wrong. That’s the start of the diseases asbestos causes: asbestosis, pleural plaques, pleural thickening, lung cancer, and mesothelioma.

Most people exposed to asbestos in Britain did it at work, often unknowingly, often while being told it was safe. Many were children when first exposed: school caretakers’ families, the children of laggers and shipyard workers brought it home on overalls. The fault lies with the people who knew and kept selling it.

The latency — the time between breathing the fibres and the disease showing up — is long. For mesothelioma it’s typically 20 to 60 years. That’s why someone diagnosed in 2026 may have been exposed in the 1960s, 70s or 80s. It’s also why we’re not yet at the end of the wave.

You don’t need a heavy industrial history to have been exposed. Some routes you’ll meet in chapter 1.4.