"Contrary to statements being made by third parties, the European Food Safety Authority (EFSA) has not carried out a risk assessment on ITX to date," the Parma-based regulator said in a statement.
The regulator added: "EFSA has not been able to determine the safety of ITX but rather has made a preliminary statement based on very limited data."
The correction adds to the high profile both companies received after Italy's food safety regulators detected ITX in some batches of the Nestlé's products in September. The statement may fuel consumer concerns that the companies have been trying to hide the effects of the chemical, even as they say scientific advice indicates that there is no risk to human health.
Tetra Pak says it stopped using ITX in the packing for the affected Nestlé products in October after being informed of the problem. The company is phasing out the use of ITX in other fatty liquid products and for some juices. ITX is used in the curing of ink during the ultraviolet printing process.
The ink curing agent was found to have migrated through the packaging and into the milk. The packaging was produced by Sweden-based Tetra Pak
In its original statement on ITX on 24 November, the food regulaor said: "On the basis of the very limited data available today, the presence of ITX in food could be considered undesirable but it is not likely to present a health risk at the levels reported."
EFSA is carrying out a risk assessment of ITX at the request of the Italian government. EFSA said it would provide preliminary advice on the chemical sometime this week and expects to deliver its final opinion no later than March 2006.
In the new dispute with claims made by Nestle and Tetra Pak, EFSA also published the letters it sent to both companies.
In the letter to Tetra Pak's chief executive office, Nick Shrieber, EFSA said that a full-page advertisement Tetra Pak took out in Italian newspapers last week was incorrect in claiming he agency had advised that ITX was non-toxic.
In the letter to Peter Brabeck-Letmathe, Nestle's chairman and chief executive, the regulator disputed the Swiss company's claim that the agency had deemed milk contaminated with ITX to be "no immediate health risk".
"The ESFA maintains that this statement, which implies the endorsement of the safety of Nestle's products currently on the market, does not reflect the nature of the scientific advice given to date by the authority and is potentially misleading," the regulator wrote.
In other developments, a meeting of the EU's food and feed safety panel met on 30 November to discuss ITX and stated that: "On the basis of the knowledge available today, the Standing Committee agreed that there is no need to take any measures at EU level such as withdrawal of the concerned products from the market."
ITX hit the headlines two weeks ago after Italian authorities confiscated millions of litres of Nestlé baby milk and got a court order to force the company into recalling about two million litres of its Nidina and Latte Mio brands in Italy. Nestlé extended the recall to France, Spain and Portugal. Dutch group Numico was also involved in recalling some of its products.
ITX is not prohibited for use in food packaging by the EU, she said. It is also not listed on the World Health Organisation's prohibited list. Scientific research indicates that the migration of ITX has "no known health effects", according to Tetra Pak.
Tetra Pak's testing indicates that the migration of the chemical through the packaging occurs when the product inside is a fatty substance, like milk. Additional testing by Tetra Pak revealed that no migration was occurring for most juices. Some some citrus and milk juices are affected and the company is phasing out use of the chemical for those products. Clear juices such as as apple, grape and cranberry do not seem to be affected.
Italy had originally informed the European Commission rapid alert system about the ITX problem in September. However, regulators were unhappy that there was still some product left on the shelves and under a court application got a Italian judge to demand the Nestlé recall.
Nestlé denies there was a safety risk to human health and said the recall was due to consumer concern about the products. Nestlé cited what it calls a broad scientific consensus that supports its conviction that ITX does not pose a health hazard.
Nestlé also ran into difficulties with Italian regulators earlier in October. Italy's antitrust authority fined seven producers of baby formula, including Nestlé, a total of €9.7 million for price fixing.
The evolving issue over ITX highlights the uncertainty surrounding current legislation in the EU over the food industry's use of packaging chemicals, a problem that is meant to be fixed under a proposed directive on the registration, evaluation, authorisation and restriction of chemicals (Reach), approved by the bloc's parliament earlier this month.
Currently the EU relies on a negative list to regulate the use of chemicals. This means any chemical not on the European Food Safety Authority (EFSA) blacklist can normally be used for packaging food.
In a 24 November 2004 patent application in the US, Sun Chemical noted: "In recent years, thioxanthone derivatives, particularly isopropylthioxanthone (ITX) and diethylthioxanthone, have been extensively used in UV curable printing ink applications. However, these are not entirely satisfactory because, following curing, unreacted thioxanthone derivatives of this type have a tendency to migrate from printing inks into, for example, packaged foodstuffs."