"detrimental" is a better choice.
of course not all are destructive..like honeybees they are beneficial to human
costructive
a volcanic eruption for example is both beneficail and destructive. it does indeed destroy land but but destroy ,for example, soil it truns the soil into a renewable source which in my opinion is beneficial.
Titanium is beneficial to our lives because its used in human implants and bikes etc.
It is similar to odd.(opposite defiant disorder).
Detrimental
interesting, challenging, beneficial, rewarding
Antithetical to environmental would be non-environmental or destructive to the environment.
The opposite of harmful would be helpful. You could also say beneficial or fortunate.
constructible
The opposite of having an opportunity would be a lack of one. The opposite of opportunity (beneficial situation) could be misfortune, mischance, or dilemma.
There many opinions. some say they were destructive and some say they were very helpful. it all depends on the persons opinion