Sushi lovers in Paris, and they are many, are questioning the origin of the salmon at the end of their chopsticks since the Fukushima nuclear disaster unfolded.
And Asian restauranteurs in the French capital are striving to reassure them that, even if the cuisine is Japanese, the ingredients are most probably not.
In the narrow sidestreets between Opera and the Palais Royal, ground zero for all things Japanese in Paris, sushi bars have been hardest hit in the aftermath of the March 11 earthquake and tsunami.
"We have lost a third of our clientele," said chef Eric Lin at Chez Kyotori, even though his restaurant uses salmon from Norway, sea bream from Greece, tuna from the Indian Ocean and mackerel from the North Atlantic Ocean.
"The other products, like sauces and beers, come from plants in Europe - Germany, England, the Netherlands, Czech Republic..."
To reassure the customers it still has, Chez Kyotori has taken to adding an unusual footnote to its checks: "The products billed above do not originate from Japan."
Jitters over Japanese food are "purely psychological," added Zuxii Lin, manager of Saveurs Zen (Zen Flavours), where business fell "20 to 25 percent in the week after the March 11 earthquake" before recovering.
"Only the seaweed comes from Japan, but we have a lot in stock and we can always find more elsewhere, in China or in South Korea," she said.
Over at Hello Sushi, which until recently made good use of sauces imported from Japan, manager Charlie Yang has put out the order for all ingredients to come from elsewhere.
"I called my suppliers and I told them that I do not want Japanese products," he said.
Japanese grocers in Paris have meanwhile found themselves at the receiving end of pointed questions from worried customers.
"Anxiety is growing," said Eunsun Park at Ace Mart, which stocks a wide range of Oriental foods. "They want to know if products were made before the incident, what's going to happen next and if there is sufficient inspections."
Park is awaiting a delivery at the end of this month, but due to extra cargo inspections, the ship carrying it has been delayed, and the additional expense will mean higher prices when the goods finally get onto the shelves.
"It is going to be harder than before and I am worried about what is coming next," Park added. "In case of problems, we will have to turn to Japanese products made in the United States or to Korean food."
The mood is less anxious at ramen noodle shops.
"Some of my friends who run sushi and sashimi restaurants have fewer customers, due to the fish, but here it is special," said Peng Chen, who oversees the Sapporo noodle bar.
In the immediate aftermath of the earthquake, the proprietor stocked up on ingredients and changed suppliers, but "all our fresh products come from France, especially vegetables and flour, because it is cheaper," he said.
Noodle shop customers seem less worried as well.
"I come here as often as before, three noon-hours in five," said Anne-Marie Fery, 51, a regular at the Higuma ramen outlet.
A few steps away, Annie Le Moigne, 55, was equally confident. "I am not worried," she said. "I assume that the produce comes from there and that the state is doing what is necessary."
The potential outcome of the Fukushima accident raised no alarm bells for Damien Ormancey, 34, who put matters into perspective.
"We can do nothing," he said. "It is enough to watch a television show about Chinese dumplings to no longer want to eat."