No easy answers here. I am not inclined to worry about introducing new organisms into a specific environment. Each has evolved in its own specific environment with its own complement of companion organisms, soil type, Ph level, temperature, rainfall, etc, and is unlikely to be able to establish itself in a totally new environment. The possibility of introducing new chemicals, e.g. birth control pills, OTC drugs, RX drugs, micro plastics, etc, is however, a matter of concern I had not previously considered. Tough choices ahead as increasing number of humans venture farther and farther into the backcountry.