Dr. Schulte, there is a limit of three milligrams of chromium VI per kilogram of leather. Why is this level regularly being exceeded, even in children's shoes?

The processes which lead to the formation of chromium VI in leather and also its disappearance are not yet fully known. We are aware of some of the ways in which it is produced but others are still being looked into.

Leather is tanned using chromium salts. Is the cause of contamination confined to the tanning process?

The roots of chromium VI formation can be traced to the tanneries, the tanning agent manufacturers and the leather additive manufacturers. Although chromium VI salts are rarely encountered any more in modern-day tanning processes, it is still possible for the dangerous chromium VI to be formed even from the relatively harmless chromium III salts if the tanning process is performed improperly and if combined with certain additives. The possible processes are indeed so complex that nowadays the major European tanning agent suppliers all offer chromium tanning agents which are guaranteed safe from chromium VI. They contain substances which prevent the formation of chromium VI. These tanning agents are, however, expensive and often have to be imported by those countries producing leather.

They say that the suppliers' certification cannot always be trusted. Even if several pairs of shoes in a batch have passed the test, there is allegedly no guarantee that the other shoes in the batch are free of contamination.

The leather buyers examine samples according to statistical models and this offers a certain degree of reliability that the complete batch is safe with respect to chromium VI. We cannot say in general that the test reports from foreign parts are not to be trusted but, for their part, buyers should, at the very least, have random samples tested in the country in which the goods are marketed.

So is it simply a question of luck as to whether children's shoes are affected by chromium VI or not?

It is more likely to be a matter of luck if an increasing number of different suppliers are used. We find time and again in Asia, but also in Europe, that some producers are exceptionally well informed on the subject of chromium VI and take specific measures to avoid it, while other producers have never even heard of chromium VI and have no prevention strategy in place. More often than not, however, it is these uninformed producers who are offering the lowest prices.

RICOSTA works closely together with the PFI, the Institute for Research and Testing in Pirmasens, and is thus numbered among those manufacturers who regularly undergo voluntary inspection. Which quality seals or certificates are used in the marketplace to demonstrate that a given shoe is free from harmful substances?

There are numerous producers and retailers who, like RICOSTA, invest a great deal in having their goods tested. Seals of approval, such as EcoTex 100, vouch for the safety of these goods and show that the producer or retailer is prepared to comply with market controls. Sadly these seals and labels are still few and far between in the shoe industry.

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