Photo taken on Aug. 4, 2017 shows a shelf used to sell eggs replaced by other products at an Aldi supermarket in Berlin, capital of Germany. (Xinhua/Shan Yuqi)

BERLIN, Aug. 5 (Xinhua) -- German supermarket chain Aldi has stopped selling eggs in all of its stores due to a possible pesticide contamination, the company announced on Friday.

The move was a "purely pre-cautionary" reaction to Thursday's revelations that eggs from Dutch poultry producers had been contaminated with the poisonous pesticide Fipronil.

Aldi insisted there was currently no reason to believe that customers had suffered any harm to their health.

Fipronil is a pesticide effective on a large number of pests. It is considered slightly poisonous by the World Health Organization (WHO) and is hence forbidden on animals destined for the food chain to prevent damage to the human liver, thyroid and kidney.

Aldi emphasized that in the future it would only accept eggs which were confirmed to have been tested negative for Fipronil. As a consequence, supply bottlenecks were possible in the short-term. The firm justified its decision with a desire to ensure "clarity and transparency" for customers.

German Agriculture Minister Christian Schmidt has estimated that 12 states in the country are affected by contaminated eggs. The situation in Lower Saxony and North Rhine-Westphalia on the Dutch border were the worst, according to Schmidt, but is still "under control."

Nonetheless, Christian Meyer, the state agriculture minister in Lower Saxony, demanded on Friday that Fipronil should be included in the list of substances for which food products are monitored systematically by the federal government.

By Thursday night, 138 Dutch poultry producers remained closed after investigations had revealed traces of Fipronil.

In total, 180 farms in the Netherlands were confirmed to had used an anti-lice poison which contained Fipronil. In one case the concentration was so high that Dutch authorities warned against "acute danger" to consumers of the affected eggs.