Environmental factor or ecological factor or ecofactor is any factor, abiotic or biotic, that influences living organisms.

The environmental factor is excessive sun exposure.

If you can feel it, see it, hear it, taste it or smell it, it is an environmental factor.

We tend to use the words "environmental factor" only for negative attributes, like loud noises or nasty smells. But anything that you can sense in the environment (which is everything around you) is an "environmental factor".

no

Yes.