Don’t take our word for it. Here’s every fact on this site, with its evidence grade, its caveats, and a link to the source, so you can check us.
We start you on the strong ones: findings that have been replicated or come from one large, well-controlled study. Moderate and weak facts are here too, labeled for what they are. Use “Link to this fact” to share a single card.
Fragrance is everywhere / Hypothesis
Immigrant women in the US most often work as house cleaners and make up 71% of manicurists; an expert job-exposure tool rates both jobs as probably exposed to fragrance chemicals, and house cleaning also to cleaning-product ingredients such as alkylphenols and antimicrobials.
Weak evidence: Exposure ratings from job descriptions (WORC), not measurements.
Source: Knox 2026, Journal of Exposure Science & Environmental Epidemiology Link to this fact
Fragrance is everywhere / Other evidence
About 65 percent of 500 randomly called Hong Kong households (323) said they had a dry-cleaning habit, and 93 percent of them keep the clothes in a wardrobe; 44 percent leave the cleaner's plastic bag on until they wear the item.
Weak evidence: Self-report, 1996 Hong Kong, random phone-book sample; not a measure of exposure.
Source: Chao 1998, Building and Environment Link to this fact
Information, not medical advice. See also: myths we won’t tell you.