EFSA has been asked by the European Commission to review the safety data on all additives - work that is being undertaken by its additives and food contact (AFC) panel.
First priority is being given to colours.
Some of the original safety evaluations on the 46 colours (natural, synthetic or mineral) previously approved for use in Europe date back as far as the 1960s.
New scientific data on their safety is likely to have emerged in the intervening period.
Speaking at EFSA's Scientific Forum to mark its fifth anniversary in Brussels this week, John Larsen of the National Food Institute, Technical University of Denmark, said that draft opinions have been prepared on five colours: Red 2G, Allura Red, Ponceau 4R, Quinoline Yellow, and Lycopene.
He did not give an indication of the content or sway of these draft opinions.
However, due to the potential ramifications of the Southampton study which is presently under review, progress on these is now on hold.
The AFC panels' working group on additives has introduced a preliminary step to the reassessment, to determine whether a full or a partial re-evaluation is required.
This information-gathering step has been out-sourced to RIVM in Holland.
The second stage of the process is a reversion to the working group for a decision on full or partial re-evaluation; and the third stage is for those needing re-evaluation to be made a priority.
At present, 14 pre-evaluations have been completed, including the five with draft opinions.
To date, only one final opinion has been adopted, on Red 2G. Deemed a potential carcinogen, the accepted daily intake (ADI) of 20mg/kg, established in 1981, was swiftly withdrawn and the colour subsequently banned.
The Southampton study Evaluation of the study by EFSA is an on-going exercise.
Larsen explained the methodology and conclusions in detail, and called it a "well done" study, which was double-blind, placebo-controlled.
In stage one, which lasted six weeks, 153 three-year-olds and 144 eight- and nine-year-olds were given one of two drink mixes containing artificial food colours and additives, or a placebo.
The children were drawn from the general population and across a range of hyperactivity and ADHD (attention deficit hyperactivity disorder) severities.
Mix A contained sunset yellow (E110), tartrazine (E102), carmoisine (E122), ponceau 4R (E124) and sodium benzoate (E110).
This same mix was used in an earlier study on a cohort of three-year-olds which was deemed inconclusive because the effects were not confirmed by clinicians.
Mix B contained sunset yellow (E110), quinoline yellow (E104), carmoisine (E122), allura red (E129) and sodium benzoate (E110).
Phase one lasted six weeks, with every child consuming the mixes and the placebo for one week each, and a one week wash-out period between each.
Parents were asked to keep other sources of artificial colours out of the diet, and to keep a diary of violations.
Phase two involved some of the children from the older group - responders and non-responders - during two half-day session a week apart, at which they were given either a placebo or an active drink similar to mix A or B, but the whole day's dose was given at once.
The effects on the children's behaviour were assessed using a global hyperactivity aggregate (GHA) based on aggregated scores of observed behaviours and ratings by teachers and parents, plus, for those aged eight and nine, a computerised test of attention.
The conclusions drawn by the researchers were that artificial food colours and additives were seen to exacerbate hyperactive behaviour in children at least up to middle childhood.
Assessment When the Commission asked EFSA to provide an opinion on this study, a dedicated working group formed.
Several experts on children's behaviour and ADHD have also agreed to take part in the evaluation.
Larsen said that, regardless of the study's quality, the published paper highlights a number of points that need to be addressed.
For instance, since mixtures and not individual additives were tested, the effects on children's behaviour cannot be ascribed to any one additive.
The time of day at which the drinks were consumed is not clear.
Moreover, in the GHA scores, subjective and objective scores were combined.
There is a need to consider whether this was appropriate, said Larsen.
Additional material
In addition to the paper that was published in The Lancet , Larsen said that EFSA has received other study reports from the authors, which were forwarded by the UK's FSA.
This means that the working group has more than just The Lancet paper to work on.
Although he stressed that the review is still underway, this additional material has thrown up some interesting points.
In post hoc analysis, parental reports were the main contributor to the GHA score for the three-year-olds, but this factor was not included in the publication.
This begs the question who is in the best position to see the changes in children's behaviour - their parents or other professionals?
"Maybe parents are more sensitive to behavioural changes," said Larsen, but he added that parents' observations could have been down to the timing of drink consumption.
If drinks were being drunk after school, only parents would have been present to witness the results.
In eight- and nine-year-olds, the largest contribution to GHA was computer-based.
EFSA's opinion on the study is expected in February 2008.
A spokesperson for EFSA told FoodNavigator.com in July that the additives review is expected to be completed by the end of 2008.
The impact of the Southampton study review on this target is not known.