This is the 14005th most frequent German word.
gefährden
"Gefährden" means "to endanger" or "to put at risk."
In this sentence, 'gefährden' is used to describe the act of endangering health, as a general effect of smoking.
Das Rauchen kann die Gesundheit gefährden.
Smoking can endanger health.
Here, 'gefährden' is used to describe the potential to harm or risk others on the road due to reckless driving.
Wenn du zu schnell fährst, könntest du andere Verkehrsteilnehmer gefährden.
If you drive too fast, you could endanger other road users.
In this context, 'gefährden' signifies the negative impact to biodiversity caused by pollution.