That's an excellent and practical question for city living. For a high-use urban trash bin, the most hygienic lid is one that minimizes direct hand contact while reliably containing odors and debris. Based on that, the top contenders are hands-free pedal-operated lids and self-closing, swing-top lids.
The pedal-operated design is arguably the gold standard for public or shared spaces. Users can open the lid by stepping on a pedal, keeping their hands completely away from the potentially contaminated surface. This drastically reduces the spread of germs. The lid should be robust and close smoothly to prevent slamming and ensure it's usually covered.
A close second is a sturdy, weighted, or spring-loaded self-closing swing lid. These lids open easily with a gentle push and then automatically swing shut, preventing the bin from being left open. While a hand might touch it, the automatic closure ensures containment. Look for models with a touch-point that is as smooth and non-porous as possible, like stainless steel, which is easier to clean and disinfect than plastic.
Avoid simple flip tops or lids that must be manually lifted and held open. These become hotspots for bacteria and viruses. Also, ensure the lid material is durable and easy to wipe down regularly.
In summary, for ultimate hygiene in a high-traffic urban setting, prioritize a hands-free pedal bin. If that's not feasible, a high-quality, self-closing swing lid with a smooth surface is the next best option. The key is creating a barrier between users and waste without relying on manual contact.