Toxic heavy metals are found in many chocolate bars including Hershey’s and Ghirardelli’s

Dark chocolate has long been seen as a healthy dessert — but a new report suggests the treat may actually be harmful.

A new investigation by Consumer Reports has found that dark chocolate bars may contain heavy metals linked to a wide range of health problems.

The organization tested 28 dark chocolate bars from the following brands: Hershey’s, Ghirardelli’s, Lindt’s, Dove, Godiva, Trader Joe’s, Hu, Mast, Taza Chocolate, Valrhona, Beyond Good, Equal Exchange, Scharffen Berger, Alter Eco, Pascha, Tony’s, Lily’s Chocolove, Endangered Species, Theo and Green & Black’s.

The researchers found that all 28 chocolate bars contained cadmium, a naturally occurring element found in soil that ends up in cocoa beans. and lead, which naturally contaminates grain through the environment.

Heavy metals have been linked to a variety of health issues such as lung problems, memory problems, cancer, and even early death.

Lead specifically is well known to be dangerous to humans, with long-term exposure causing memory loss, high blood pressure, abdominal pain and low mood in adults, and brain and central nervous system damage leading to learning and behavior problems in children.

Even low levels of cadmium are considered carcinogenic and have been linked to kidney cancer and osteoporosis, according to the Centers for Disease Control and Prevention.

James Rogers, director of food safety and testing at Consumer Reports, said that while the products do not contain extremely high levels of minerals, they still contain levels high enough to be a health concern.

For 23 of the 28 bars, eating just one ounce per day would put an adult over the level for at least one of the minerals for harmful effects. Five of those bars had above those levels for both cadmium and lead. Five of the bars had relatively low levels of both.

Consumer Reports used the California Maximum Allowable Dose (MADL) of 0.5 micrograms of lead and 4.1 micrograms of cadmium to determine health risk levels.

Many chocolate bars with levels of concern have the word “organic” on the label, which is no guarantee that toxicity levels won’t be high.

The bars that were listed as high in cadmium were:

• Beyond good Pure Organic Dark Chocolate 70% Cocoa: Cadmium levels reach 112% of the California MADL
• Beyond good Organic pure dark chocolate 80% cocoa: 138%
• equal exchange Organic Extra Dark Chocolate 80% Cocoa: 120%
• Lindt Premium Dark Chocolate 70% Cocoa: 116%
• Sharpen Burger Extra Dark Chocolate 82% Cocoa: 136%
• Alter Eco Dark Chocolate Classic Blackout Organic 85% Cocoa: 204%
• Easter Holiday Organic Extra Dark Chocolate 85% Cocoa 253%
• pigeon Deep Dark Chocolate Promises 70% Cocoa: 112%

Bars that contain high levels of lead include:

• Tony Chocolonely Dark Chocolate 70% Cocoa: With lead levels up to 134% of California’s MADL
• Layla Extra Dark Chocolate 70% Cocoa: 144%
• Godiva Premium Dark Chocolate 72% Cocoa: 146%
• Chocolov strong dark chocolate 70% cocoa: 152%
• Lindt Premium Dark Chocolate 85% Cocoa: 166%
• endangered species Bold + Silky Dark Chocolate 72% Cocoa: 181%
• Trader Joe’s Dark chocolate 72% Cocoa: 192%
• he is Organic Simple Dark Chocolate 70% Cocoa: 210%
• Chocolov Extra Dark Chocolate 88% Cocoa: 240%
• Hershey Special light and sweet dark chocolate: 265%

The following chocolate bars contain both lead and cadmium levels:

• Theo Pure Dark Organic 70% Cocoa: 120% of MADL for lead, 142% for cadmium
• Trader Joe’s The Dark Chocolate Lovers 85% Cocoa: 127% and 229%
• Theo Very Organic Pure Dark Chocolate 85% Cocoa: 140% and 189%
• Layla very dark chocolate 85% cocoa: 143% and 101%
• Green and Blacks Organic Dark Chocolate 70% Cocoa: 143% and 181%

The five bars with lower levels that are listed as “safer options” are:

• mast Organic Dark Chocolate 80% Cocoa: 14% lead, 40% cadmium
• Plate chocolate Organic Delicious Dark Chocolate 70% Cocoa: 33% and 74%
• Ghirardelli Intense dark chocolate 85% cocoa: 36% and 39%
• Ghirardelli Twilight Delight Intense Dark Chocolate 72% Cocoa: 61% and 96%
• Valrhona Abenau Dark Chocolate 85% Cocoa: 63% and 73%

The National Association of Confectioners, an industry trade group, has argued that chocolate and cocoa are safe to eat and told TODAY in a statement that dark chocolate “can be enjoyed as candy as it has been for centuries.”

“The products mentioned in this study comply with stringent quality and safety requirements,” the statement continued.