Alex Renton's four-year-old daughter Lulu with her pile of banned sweets
My four-year-old daughter and I sit in front of a great heap of sweets. Her eyes are alight, like a pirate's with his treasure: Sweets are her greatest passion. Just back from a friend's party, she thinks she's hit the jackpot.

But I'm going to have to tell her she cannot have any of them. Not a wine gum, not a chewy snake, not one Roses chocolate. I've been sitting painstakingly going through the ingredients list on the back of each jazzy-coloured packet - occasionally with a magnifying glass. Amazingly, almost all of them contain some additives that I've had to decide are actively dangerous to her.

These are additives that are banned in many countries, ones that our government's Food Standards Agency (FSA) decided over a year ago should not be in our children's sweets. But they are still on sale in every supermarket and sweet shop across Britain.

I'm no health-obsessed 'helicopter parent'. We don't hover above our children, banning sweets and sugar. In fact, I roll my eyes at the army of organic-only fusspots: Children can usually be relied upon to eat what their bodies need. A little pleasure won't hurt them.

But what I've discovered about chemical food colourings and preservatives terrifies me, as it should the most happy-go-lucky parent. British sweet manufacturers, I've had to conclude, no longer deserve our trust.

Six commonly used colourings in sweets, soft drinks and even children's medicines have now been proven to cause attention disorder and hyperactivity in children - not just those already prone to such problems, but all children.

What that means is that the notorious 'sugar rush' that we've all seen in children on a sweetie or pop binge may not be caused by sugar at all, but by obscure colourings and preservatives.

And there are added dangers from these completely unnecessary chemicals. My daughter, like nearly one in 20 British children, is prone to allergies: in her case, severe asthma that means a trip to A & E once a month during winter.

During my investigation, I found dangerous colourings and preservatives in famous names such as Cadbury Roses chocolates, Maynards, Wrigley's gum, Jawbreakers, Jelly Babies, Kiddies Mix, Refreshers, Lovehearts, Hubba Bubba bubble gum and Fizz Bombs, as well as a huge range of corner-shop sweets sold as Nisha's or Family Favourites.

Novelty sweets branded on Bratz dolls and cartoon character Scooby-Doo had them too. A build-it-yourself gingerbread house from the John Lewis toy department had more bad dyes than any other item I found.

If it's cheaply made and highly coloured, it seems, it's more likely than not to have an 'azo-dye' (a synthetic nitrogen-based compound dye) in it - and that includes all the children's favourites: the snakes, marshmallows and bootlaces sold loose in corner shops.


Dangerous colourings and preservatives were found in famous names such as Cadbury Roses
The chief villains - the ones everyone agrees are dangerous - are mainly colours derived from coal tar. These are known as the 'Dirty Six' and go under the names sunset yellow (or E number 110), carmoisine (E122), tartrazine (E102), ponceau 4R (E124), quinoline yellow (E104) and allura red (E129).

They're reds and yellows, and commonly found in sweets, jellies, ice lollies, fizzy drinks and many obviously coloured foods, such as icing on cakes. Three of them have been linked with asthma and other allergies. Many of them are banned in medicines, or must carry warnings.

All of them, government scientists now agree, can cause or exacerbate hyperactivity or attention disorder.

For my daughter - who's pretty busy, not hyperactive - the worry is what's known as the cocktail effect: these colourings combined with commonly used benzoate preservatives (which go under E numbers 210 to 219) may exacerbate other allergic conditions as well as hyperactivity.

The benzoates, according to the FSA, are thought to worsen symptoms of asthma and eczema in children who have these conditions - and they're banned in food products for the under-threes.

Yet they appear in all sorts of soft drinks, from flavoured waters to Scottish favourite Irn-Bru and many brands of cola. Amazingly, carmoisine colouring is in the best- selling children's pain reliever, Calpol - which we use during our daughter's asthma attacks.

You would have thought there would be no question over getting these chemicals out of our children's diets. After all, ponceau red, quinoline yellow and carmoisine are already banned in the U.S. and several other countries.

This summer, European Parliament members voted to overrule the EU Commission's own food standards agency, and demanded warning labels for the Dirty Six colours (these won't be introduced until mid-2010 at the earliest).

The FSA decided in 2007 to call for a ban on the Dirty Six, after research it commissioned from Southampton University convinced scientists of the risks. But the Government, under pressure from the food industry, vacillated.

It took until last month for ministers to agree to a much watered-down idea: a 'voluntary phasing-out' of the Dirty Six by the end of this year.

That's not good enough, says additives campaigner Anna Glayzer: 'History shows that voluntary agreements with the food industry don't work.

'As soon as the publicity dies down, the substances creep back into ingredient lists. And many of our sweets are now made in places such as China. How is a voluntary ban going to work there?'

Irish manufacturer Zed Candy makes some gobstoppers, which it exports to Britain and all over the world. Many of the firm's sweets contain three of the Dirty Six, as well as a notorious colouring that's now rarely seen, E133.

It's called 'brilliant blue': it causes hyperactivity, skin rashes and is suspected of being a carcinogen. It's banned in Austria, Belgium, France, Germany, Norway, Switzerland and Sweden. But it isn't even on the British voluntary phase-out list.

I asked a spokesperson at Zed Candy what the company intended to do about the additives. 'We'll change the ingredients in 2010, because we don't want to have to carry the EU warning label,' said spokeswoman Eileen Maher.

Isn't that a little cynical? I asked. 'We don't believe any of our products can cause harm in proper doses,' she told me. 'There is recommended serving advice on each packet.'

That's true - on the box of 15 Mini Jawbreakers in front of me, it does say 'Serving size one piece', in a typeface a third as big as that you are reading here. You suspect such advice may not carry much weight with the average sugar-hungry small boy.

But the most outrageous thing I found on the sweet shelves was in the familiar blue box of family favourite Roses Chocolates. Their ingredients list has been cleaned up: the E numbers have all gone. Now under colour is listed 'sunset yellow'.

This pleasant-sounding phrase is the layman's term for the Dirty Six colour E110 - banned in Norway and Finland, linked to all sorts of allergies, banned for use in food here for the under-threes, and supposed to carry a health warning if used in medicines. It is a version of the notorious carcinogenic Sudan 1.

I rang the customer helpline at Cadbury, which owns the Roses brand. 'We don't use any artificial colourings - all the ingredients are natural now, and chocolates have never contained them,' a helpful lady called Audrey told me. So how come it's there on the label?

Cadbury makes Maynards wine gums, in which I found two of the Dirty Six, but Audrey insisted: 'Wine gums are all natural now.' This is plainly untrue. When pushed, on Roses she conceded that sunset yellow 'sometimes can cause problems'.

Another large manufacturer, Glisten Foods, is responsible for a lot of the cheap brands sold in corner shops and newsagents - often using better-known names such as jelly babies. Glisten, which is based in Yorkshire, refused even to talk to me about its use of the Dirty Six colours.

Some of the big-name manufacturers have made changes since the FSA reported in 2007. Swizzel Matlow, which makes Refreshers and Lovehearts, says the sweets I found must be old stock - the Dirty Six colours have not been used in its factories since last April.

Cadbury, Nestlé, Mars, Haribo, Coca-Cola and Hartley's jams have all begun changing ingredients and boasting 'no artificial colours' on their labels. You may, though, question whether their use of the word 'natural' has much to do with your understanding of it.

Nestlé's large tube of Smarties includes the following 'non-artificial' colourings: titanium dioxide, carminic acid and copper complexes of chlorophyllins. Carminic acid, for one, is made from insects and has been linked with the severe skin condition urticaria.

It would be wrong to think that it's just cheap sweets that contain the colours. To my horror, I found that my father's favourite treat - Meltis New Berry Fruits, 'made to a traditional recipe' - is laden with Dirty Six colours. Posh sweets such as the Ambassador's brand, sold in John Lewis at £4 a packet, also have them.

This is all the more surprising because John Lewis has a policy against additives. So does Co- op supermarkets, which in 2007 issued a statement saying that it was removing 12 chemical colours linked to allergies and hyperactivity from all its own-brand products - from sweets to tinned peas.

Yet the Co-op seems to have refilled its shelves with other manufacturers' brands that do contain them.

This sort of cynicism does not surprise Action On Additives' campaign coordinator Anna Glayzer. Manufacturers exploit the public's ignorance, she says. ' "Free of artificial colours and flavours" is the label of the year - it's fashionable.'

I asked Dr Clair Baynton, head of novel foods, additives and supplements at the Food Standards Agency, why politicians have been so slow to act on these colourings.

The evidence, she said, was 'just not strong enough' to ban the Dirty Six colours outright - and sodium benzoate plays a useful health role as a preservative.

Dr Baynton insisted 'voluntary phasing-out' will work, after talks with British sweet manufacturers. 'We're happy that they have been moving ahead with removing those substances for some time. We'll have the European label rules in 2010. And from early this year we'll be giving consumers more information on the FSA website.'

But that's going to make very little difference in the corner shop, I suggested. 'I appreciate it's difficult where you've got children spending their pocket money without parent control,' she agreed. She hoped that local council trading standards officers would be able to step in.

To me, as a parent and a food journalist, this seems completely unsatisfactory. The manufacturers are, surely, just taking these risks to maximise their profits.

As their changes show, there's no need to use these colours - they are all replaceable with fruit-based or other 'natural' substances. These are not even more expensive. The only reason for using the tar-based dyes and preservatives is to get a longer shelf-life.

It seems the height of greed. And it symptomises the great betrayal of faith that these old and much-loved food brands have practised on the public for decades.

A good recent example is the fuss over trans-fats, widely used in the snack and cake trade because they were cheap, stable and prolonged shelf-life. Companies resisted replacing them until public and scientific pressure became so great that they had to - and now packets boast that they are 'trans-fat free'.

Meanwhile, the very language that describes food has been perverted. Ordinary terms that we can understand have been hijacked by the food business, with the tacit approval of government regulators.

'Words such as "natural" and " farmhouse made" imply that food is traditional and of better quality,' says Emma Hockridge, of the organic lobby group the Soil Association, which allows hardly any additives in products that get its certification.

'But they're routinely abused by the big food companies. Government says trading standards officers can police these things: but how, say, is Slough Council going to take on the might and legal muscle of an international manufacturing giant?'

What distresses me as a parent is that it's now demanded that I be a scientist and an expert internet researcher just to make sure my children are not put at risk by their sweets and snacks.

No one wants a family row over what are supposed to be treats. But I'm just going to have to learn to say No to my children.