What Household Chemicals Should I Avoid?
The household chemicals most worth avoiding are PFAS, phthalates, formaldehyde, flame retardants, lead, cadmium, combustion particles from gas stoves and chlorination byproducts in water. These substances appear in our home products, indoor air, and water, and have well-documented hazard evidence at residentially relevant levels. The full database below covers substances organized by where they show up in at home. A reminder that this is a hazard list, not a risk list, and the two aren’t the same. You can read more about why in Part 2 of the course.
By Dr. Meg Christensen | Physician-founder of Interior Medicine, a non-toxic home resource built on her background in medicine, biochemistry, epidemiology, and clinical research.
Published May 26, 2026 | Updated Nov 10, 2026
Welcome to What "Non-Toxic" Actually Means, a free course on how to read product claims and navigate healthier materials more clearly. Stay here, or if you'd like the full arc, the Intro is the best place to start.
Part 6 takes ~10 min to read
Is It Non-Toxic? A Clear Process You Can Use
Sections 6-9 of the course are all about the tools you can use to decide whether a product is non-toxic. I can't make that decision for you, because doing so would collapse the six-step framework into one step, and I'd be projecting my susceptibility assumptions, my precautionary stance, and my risk tolerance onto a decision that should be yours. Instead, we sort the six steps by who can answer them. Hazard, exposure, and dose are knowable from outside data, so I'll show you how those fill in the framework. Susceptibility is partly knowable from outside data and partly knowable only to you. Risk tolerance and precautionary stance are knowable only to you, so you'll bring those.
If it feels like a lot, there's a tool at the end of the course that walks through the framework for you on any specific product. If you'd rather see the tool first and decide whether you want the background, that works too.
Otherwise, let's get started with: Hazard!
Here is the huge list of hazards in the home. Every institution, brand, and blog has a different set of chemicals to prioritize avoiding, and I didn't want to come up with another arbitrary set. So this is everything, compiled together.
Hold it lightly and don’t worry too much. As you know well by now, hazard is just the first step.
The course is being update right now (November 2026). After you’re done with this shortened part 6, move to Course Part 7 ➜