Consumerlab.com said that while red yeast rice products had clinical backing demonstrating their effectiveness as pharmaceutical statin alternatives, manufacturers needed to be wary of a problem that has the potential to become a health hazard.
Citrinin is a mycotoxin of varying toxicity that can occur in grains and rice but its effect on human populations has not been determined although higher rates of kidney disease have been reported in the Balkans where elevated levels of citrinin exist.
"What we noticed was that the levels of citrinin were highest in the products that had the lowest amounts of monacolin-K and so there may be a connection," Consumerlab.com President Tod Cooperman told NutraIngredients-USA.com.
"We hope the products that have been found to be contaminated will be altered and all companies manufacturing these products will test their products to ensure they are not contaminated."
Monacolin-K is otherwise known as lovastatin (the active agent in red yeast rice).
He said that while the danger to public health was not known until further studies were conducted, consumers would gravitate toward products they knew not to be contaminated.
"It is clear these products can be effective as the science backing them is very strong but it is important consumers have the information so they can choose products that are going to be safe and effective."
A State of Pennsylvania-sponsored study published today in Mayo Clinic Proceedings found a red yeast rice supplement along with fish oil and lifestyle changes reduced LDL cholesterol levels by 42 percent.
This compared to a 40 percent decrease among people treated with the drug simvastatin (40 mg/day) and traditional counseling.
The survey The survey found the levels of lovastatin in the ten products tested could vary by as much 100-fold, with some reaching prescription level and others registering barely any active components at all.
Labels generally do not disclose their lovastatin levels because their manufacturers do not wish them to be considered as drugs by the Food and Drug Administration (FDA).
Lovastatin is also used in the prescription drug Mevacor.
"This makes it difficult for consumers and doctors to assess and compare red yeast rice supplements, although they remain widely used," Consumerlab said.
Red yeast rice contains lovastatin and other nutrients including a hydroxy acid form of lovastatin and plant sterols, which may contribute to the supplement's effectiveness.
The American Heart Association estimates more than 30 percent of Americans have elevated LDL cholesterol (130 mg/dL or higher).