can kill the people from their consequences

No, it is a mixture of 3 chemicals with a probable additive of a fourth.

" Unintended consequences? " Scientific theories are explanations of natural phenomenon. Only humans can make " consequences ", theories explain things.

Assuming your question is typoed and should read; "What does 'weigh the consequences' mean?"

It is a phrase that means consider the probable outcomes of your actions before doing them.

natural consequences of the law of universal gravitation