The industry group Wine Institute dismissed the lawsuit as "irresponsible," adding it has not called for any vintner to pull any of the wines named in the complaint from store shelves.
The complaint, which seeks class-action status, was filed Thursday in Los Angeles Superior Court. It lists as defendants 28 California wineries. It also asks for unspecified damages and a halt to production of arsenic-tainted wine.
"We believe this allegation is false and misleading and that all wines being sold in the U.S. marketplace are safe," the institute, which represents more than 1,000 California vintners and related businesses, said in a statement.
Institute spokeswoman Gladys Horiuchi said Friday that although the United States doesn't have specific arsenic levels for wine, many other countries do. She added that California vintages have never come close to exceeding those levels.
According to the lawsuit, tests by three independent laboratories found that in some cases arsenic levels were 500 per cent higher than what's considered safe. Horiuchi said those comparisons were based on levels considered safe for drinking water, not wine.
The lawsuit's lead attorney, Brian Kabateck, said the levels were originally found in tests done by the head of the Denver-based lab BeverageGrades.
"He decided to test 1,306 bottles of wine representing more than 75 per cent of the wine consumed in the U.S." Kabateck said Friday. "Out of those he found 83 that had excessive arsenic levels."
The attorney added that subsequent cross-testing at two other labs confirmed the findings.
Arsenic occurs naturally in the air, soil and water in small amounts, as well as in wine and other beverages. In larger amounts, it can be deadly.
Kabateck said tests showed the arsenic found was "inorganic" or not naturally occurring. He said it might have been introduced in the vinting process. He noted nearly all of the affected wines sell for between $5 and $10 a bottle.
"Out of 1,306 tests only 83 came back," he said. "We know that the vast majority of the wine business is safe. If you're spending $20 on a bottle of wine you're not going to have concerns most likely."