That first cup of coffee is pure bliss for those people needing their morning caffeine fix, whether it is prepared with milk, sugar or simply black. But how about a splash of mycotoxins? A new study confirms the presence of these toxic metabolites produced by fungi in commercial coffee samples, leading to concerns about potential public health risks.

The study - led by Dr. Emilia Ferrer of the University of Valencia in Spain - is published in the journal Food Control.

She and her colleagues explain that mycotoxins are compounds produced by filamentous fungi - such as Aspergillus or Fusarium - that cause disease and health issues. These compounds can be carcinogenic and may affect the hormonal and immune systems.

Mycotoxicoses is the toxic effect of mycotoxins on animal and human health. Exposure to these compounds is typically by ingestion, but it can also occur through the skin or by inhalation.

According to the World Health Organization (WHO), general interest in mycotoxins came about in 1960, when turkey X disease - a form of mycotoxicosis that was related to animal feed - arose in farm animals in England.

From this, it came to light that these toxins are hepatocarcinogens - agents that cause cancer of the liver - and thus began more widespread research into mycotoxins.

The presence of these toxins on grains, nuts and other products that are susceptible to mold is determined by environmental factors, including temperature, humidity and amount of rainfall during harvesting cycles.

Because the occurrence of mycotoxins in foods and feeds is not entirely avoidable, regulations allow small amounts of these toxins to be present in these products.

In this latest study, the researchers carried out their analysis by using a methodology called liquid chromatography-tandem mass spectrometry (LC-MS/MS), which involves coupling a molecular separation technique with another technique to accurately identify molecules according to their weights.

Dr. Ferrer and colleagues analyzed 100 coffee samples sold in supermarkets in Spain to confirm the presence of mycotoxins.

In detail, they found the presence of fumonisins, aflatoxins, trichothecenes and emerging mycotoxins in concentrations ranging from 0.10-3.570 μg/kg. They also found that five of the samples contained ochratoxin A in amounts that exceed the current maximum permitted levels.

"The only legislated mycotoxin is ochratoxin A," says Dr. Ferrer. "We have detected low concentrations of this mycotoxin in the coffee samples, although five of the samples exceeded permitted levels."

Ochratoxin A has previously been associated with kidney disease and urothelia tumors in humans, and as such, European legislation has set a maximum permitted level of 5 μg/kg for roasted coffee beans or ground coffee, and 10 μg/kg for soluble or instant coffee.

The researchers explain that the five samples that exceeded this limit consisted of two samples of decaffeinated coffee (6.20 and 9.30 μg/kg), two samples of coffee capsules containing caffeine (6.91 and 11.43 μg/kg), and one decaffeinated coffee capsule (32.40 μg/kg).