Authorities in Ecuador have named a suspect in their investigation of now-recalled lead-tainted applesauce, which has been linked to poisonings of more than 400 Americans across 43 states, the Food and Drug Administration announced Tuesday — but U.S authorities have “limited authority” to take steps against him.

Ecuador’s authorities allege that Carlos Aguilera, a cinnamon grinder in Ecuador, is “the likely source” of the poisonings, the FDA said in an update, noting that the investigation by the Agencia Nacional de Regulación, Control y Vigilancia Sanitaria and legal proceedings to determine responsibility for the contamination are still ongoing.

U.S. authorities have said for months that they suspected that the lead poisonings could be intentional, saying one of the theories they were pursuing was that it was the result of “economically motivated adulteration” of the cinnamon used in the applesauce.

“FDA’s investigation is ongoing to determine the point of contamination and whether additional products are linked to illnesses,” the agency said in its statement.

Other spices, such as turmeric, have been intentionally tainted using lead and other substances in the past, by sellers looking to hide defects in their products or otherwise inflate the amount of money they can make.

Testing of cinnamon sticks that Aguilera had sourced from Sri Lanka but not yet processed were tested by Ecuador and were not contaminated with lead, the FDA said. 

The FDA previously said that ground cinnamon supplied from Ecuadorian distributor Negasmart, which ended up in WanaBana’s applesauce, tested for levels of lead and chromium contamination at “extremely high” concentrations far above what experts think is safe. 

In December, the FDA cited WanaBana for failing to test its cinnamon applesauce pouches for heavy metals. The agency said the applesauce maker should have taken steps to mitigate the risk that cinnamon it was buying for its pouches could be tainted with lead and other toxins.

But the agency has also stopped short of definitively describing the lead poisonings as intentional, as opposed to the result of an accident or environmental contamination.

Last year, FDA officials said its probe of the then-unnamed grinder suspected to be behind the poisonings had been hampered by limits to their jurisdiction in Ecuador. 

“The FDA has limited authority over foreign ingredient suppliers who do not directly ship product to the U.S. This is because their food undergoes further manufacturing/processing prior to export. Thus, the FDA cannot take direct action with Negasmart or Carlos Aguilera,” the FDA said in its Tuesday update.

It is unclear what direct action the FDA would otherwise take, if Aguilera had been a supplier within its jurisdiction. It is also not clear what other theories the FDA is pursuing for why Aguilera’s ground cinnamon was tainted with lead.

An FDA spokesperson was unable to immediately provide a response to a request for comment.

“My child’s favorite snack”

At least 413 cases of lead poisoning have been linked by health departments to the recalled applesauce pouches, according to the Centers for Disease Control and Prevention. 

The agency previously said most reported cases had been in young children, with the median age of cases at around two years old.

Complaints filed by parents with the FDA, obtained by CBS News through a Freedom of Information Act request, say that some children had been consuming multiple pouches daily of the cinnamon applesauce before the recall.

“I can’t believe something so toxic that’s geared towards babies, toddlers, and young children fell through the cracks and now has affected my child and others,” one person wrote, after they said their daughter had consumed the pouches.

The 2-year-old’s lead levels tested as high as 25.4 deciliters per microgram, the complaint said, far beyond the thresholds when the CDC urges parents and doctors to take steps to address lead poisoning.

The CDC warns young children are especially vulnerable to the array of serious long-term harms caused by lead poisoning, including damage to the brain and nervous system. 

“So sad to lose complete faith in a company that was once my child’s favorite snack,” they wrote.