The most likely basis is that the hotel uses standard cleaning products. Or there might be tobacco smoke near the lounge, aspirin in the medical kits, alcohol a

The most likely basis is that the hotel uses standard cleaning products. Or there might be tobacco smoke near the lounge, aspirin in the medical kits, alcohol at the bar or car exhaust in the parking garage. The warning signs provide no actionable information to consumers, but businesses can be sued for not having them so virtually all businesses in California just post the sign in self-defense against opportunistic lawyers. You can look up what chemicals are covered here: https://oehha.ca.gov/proposition-65/proposition-65-list/ https://oehha.ca.gov/proposition-65/proposition-65-list/