OK, I can see health effects starting soon, lf not already. I know I have increasing boughts of kidney stones. And my Urology group started a separate phone channel just to deal with Kidney Stones.
If the body might have to start permamently compensating, what ever that means, at levels as low as 430. And we are at 407, rising 3+ points a year. We could be touching the 430 mark around 2025, 8 years from now.
Although it would be a couple more years before CO2 was always over 430. And then it would depend on where on the planet you were.
But the below quote sounds like extrapolation to the nth degree. I would like to see the evidence to back this claim up.
In the extreme case lifespans could become shorter than the time required to reach reproductive age. This could threaten the viability of human and animal species without interventions such as the creation of artificial living environments.