Ninth-floor apartments sell for 5 percent less because of a fake internet rumor about dust.
April 20, 2026
Original Paper
Environmental Misinformation and Housing Prices
SSRN · 6602165
The Takeaway
Homebuyers in some regions believe that a specific middle band of floors in skyscrapers is more exposed to pollution. This dust floor rumor is a total myth with no basis in physical science. Even though the information is false, it has a massive impact on real estate prices. The penalty for owning a unit on these floors grows even larger during sandstorm seasons. We assume that housing prices are driven by objective factors like square footage and location. This case proves that a single piece of viral misinformation can destroy thousands of dollars in property value.
From the abstract
This paper studies how environmental misinformation distorts housing prices and how real environmental events affect the distortion. Using transaction-level data on China’s pre-sale housing market, we examine a persistent “dust-floor” rumor, which claims that apartments on floors 9 to 11 of a building have higher exposure to particulate matter pollution. Our identification leverages exogenous variation in air quality, combined with a shock on buyers’ attention to the rumor led by a developer liq