New method to detect drugs in milk

A new detection method could provide an effective way of detecting contaminants in milk, according to new research.

The technique was investigated in a recent study, published in the Journal of Agricultural and Food Chemistry.

The method can detect 20 different drugs in cow, goat and human milk, according to researchers from Jaén and Córdoba University in Spain and the Abdelmalek Essaadi University in Morocco who ran the study.

Using the technique, the researchers analysed 20 samples of cows’ milk (fresh, whole, semi-skimmed, skimmed and powdered), goats’ milk (whole and semi-skimmed) and breast milk from human volunteers.

Samples of the three milk types were found to contain anti-inflammatories, they said.

Drugs include different kinds of antibiotics, anti-inflammatories, antiseptics, lipid regulators, beta-blockers and hormones in these milk varieties.

The technique

The technique uses a “system of continuous extraction of substances in solid phase” and classifies them using “gas chromatography-mass spectrometry”.

“The validation results clearly show that this method is the most sensitive and one of the most selective described to date in the scientific literature,” said Ballesteros.

“It is also highly precise and exact, with short analysis times (around 30 minutes)”.

Findings

It was found that the drug content differs according to the type of milk, said study director Evaristo Ballesteros.

The largest number of pharmacological substances were found in whole cows’ milk, they said, particularly three anti-inflammatory drugs; niflumic acid, mefenamic acid and ketoprofen and the hormone 17-beta-estradiol.

Niflumic acid was also found in goats’ milk, along with flunixin.

The human milk analysed also contained anti-inflammatory drugs (such as ibuprofen and naproxen), as well as the antiseptic triclosan and some hormones, such as 17-alfa-ethinyl estradiol, 17-beta-estradiol and estrone.

Although the study confirms the validity of the method, the results cannot be generalised to all kinds of milk due to the small number of samples analysed, said the researchers.

Future use

Food quality control laboratories could use the new tool to detect drugs in milk or other products before they enter the food chain, said the scientists. “This would raise consumers’ awareness and give them the knowledge that food, aside from its good organoleptic properties and good value, it is also harmless, pure, genuine, beneficial to health and free of toxic residues.”

Source: Journal of Agricultural and Food Chemistry