If anyone believes that any juice is absolutely safe, then they're labouring under a misapprehension.
Whilst there are degrees of potential risk, there is no absolute guarantee of safety... we're all guinea pigs to an extent and if 20 years down the line a plausible link between juice ingredients that we now consider to be relatively safe turns up, then it's just bad luck for us I suppose.
If anyone is overly concerned about flavouring ingredients in any particular brand of eliquid then it's their choice to not use it.
If the concern is deeper, people can choose to use unflavoured juice.
If concern is even deeper (possibly some folk might be concerned about using nic content), people are free to choose zero nic, unflavoured juice.
If concern is overwhelming, people can choose not to vape at all... although that won't protect them from other contaminants/particulates in the air they breathe in.
Whilst we can choose to listen to advice from many different sources (be that from Dr F, online bloggers or whoever) to help us make up our own minds, nobody forces us to use any particular brand of juice (or mod, or atty, or wicking material etc.).
Do your OWN risk assessment, weigh up the pros and cons from your OWN perspective, make your OWN choices based upon this and take responsibility for your OWN choices.