A possum carcass can take up to 6 months to decompose depending on the weather, so that means other non target animals can eat it and get poisoned too.
If other animals eat an animal that has been poisoned by 1080, there is a high chance of secondary poisoning.
To kill a 68kg man it only takes 1/500 of an ounce.
There is no cure for the poison.
Because of the food chain 1080 poison can travel through a lot of non target animals.
There are a lot of side effects if being infected by 1080 such as, anxiety, nausea, vomiting and depression. These can effect animals, but it can also effect people.
I do no think 1080 should be used, because of all the risks there are. If someone gets poisoned by it the there is no cure for it so there is a high chance you will die. 1080 is also highly toxic to dogs and other non target species.