Any product being sold in the UK has to be authorised as fit for human consumption. If the names above are featuring in products that you can buy via regular retail outlets - as opposed to some on-line retailer overseas - they will be safe. Having said that, the cumulative effect on the human body of repeated intake of artificial flavours, colours, sweeteners, preservatives etc is not properly understood as they've only been around for the last 50 - 60 years. Therefore err on the side of caution & try to reduce your intake of all heavily processed, sugary, salty, fatty 'food-like substances' in favour of more natural, unprocessed wholefoods.
Haven't heard of any of them but if they are artificial I'd avoid them like the plague as they play havoc with your body.
Paris Hilton (that well known philosopher!) got it right when she said "Diet Coke is for fat people" - artificial sweeteners make you crave more sugar because they create massive spikes and huge dips in your blood sugar levels so you want even more.
I'm a bit at this whole 'sugar is the devil' attitude that seems to be very prevalent just now (I don't mean this thread, I mean in RL and the wider web). As cogito says, everything on sale in the UK is 'safe' but I try to limit the amount of 'engineered' food I eat. That doesn't mean I never drink a diet coke, but that it's a very rare occurrence.
If you want to cut down on sugar, cut down on processed foods. If you want to cut down on artificial sweeteners, cut down on 'low fat' processed foods.
Does a little bit of sugar harm anyone? I think some people are 'addicted' and agree with greta above, but most people? Nah, not buying it. A slice of cake really doesn't hurt as long as it's not the whole cake. iyswim.
Stevia is a herb from north America. I have a plant of it on my conservatory windowsill. It is totally natural and is naturally sweet. If you pull off a leaf and chew it it tastes like a mouthful of sugar. There was a story that when it was first discovered in the eighteenth century the sugar plantation owners led by Tate and Lyle supressed knowledge of it reaching Europe. Anyway whatever the truth of that you can buy plants now from the specialist herb nurseries.