The company, which forms part of the Lonza Group, was obliged to tell Kemi it had made changes to the product, which is different from the Tanalith products sold by the company in the UK, as required in the organisation’s rules, before releasing the new formulation in Sweden during 2012.
A changed version of Tanalith E-7, different from the formulation sold during 2012, has now been approved by Kemi, although the latter has had to refer the company for not following due process.
The Swedish Wood Preserving Association (SWPA) highlighted what had happened in a letter to producer members in April. It has also commissioned a study on the new Tanalith E-7 formulation registered, which will also cover the product changed last year, plus the older version.
Arch Timber Protection AB will pay for the study to be undertaken by the Nordic Wood Preservation Council (NTR).
Mikael Westin, who is managing director of SWPA and secretary-general of the NTR, said in May the NTR’s technical board had decided to keep Tanalith E-7 on its approved product list after receiving information from Arch Timber Protection AB about the product change.
He said that they were not worried about earlier reports of leaching of Tanalith E-7 because these were "at a very low level".
But he said Arch Timber Protection AB, like all treatment companies, must "take all responsibility for its products on the market".
He added that the formulation issue had been widely discussed in the Swedish preservation market, which was "fiercely competitive".
A spokesperson for Stockholm-based Arch Timber Protection AB told TTJ the changes in product formulation had been very small, did not involve the active ingredients and would not affect product performance.
"We made a technical mistake by not informing the Swedish Chemicals Agency of the changes," said the spokesperson. "Due process was not followed and we have apologised and accepted that."
