Validation and Use of an Accurate, Sensitive Method for Sample Preparation and Gas Chromatography–Mass Spectrometry Determination of Different Endocrine-Disrupting Chemicals in Dairy Products

Abstract

Endocrine disrupting chemicals (EDCs) are exogenous substances capable of altering the human hormone system and causing various diseases such as infertility and cancer as a result. In this work, a method for determining twenty-three different EDCs including parabens, alkylphenols, phenylphenols, organophosphorus pesticides, bisphenol A and triclosan in dairy products was developed. Samples are conditioned by addition of acetonitrile containing 1% formic acid, centrifugation and clean-up of the extract by continuous solid-phase extraction. EDCs in the extract are derivatised by heating in a microwave oven and quantified by gas chromatography–mass spectrometry. The proposed method features good limits of detection (6–40 ng/kg) and precision (relative standard deviation < 7.6%); also, it is scarcely subject to matrix effects (1–20%). EDC recoveries from spiked samples ranged from 80 to 108%. The method was used to analyse a total of 33 samples of dairy products including cow, sheep and goat milk, yoghourt, milkshakes, cheese, cream, butter and custard. Bisphenol A was the individual contaminant detected in the greatest number of samples, at concentrations from 180 to 4800 ng/kg. 2-Phenylphenol and ethylparaben were found in more than one-half, at concentrations over the range 130–3500 and 89–4300 ng/kg, respectively. In contrast, alkylphenols, organophosphorus pesticides and triclosan were detected in none.

Bisphenol A in dairy products, amount, potential risks, and the various analytical methods, a systematic review

“…In the Colón/2021 study, the amount of bisphenol in cow, sheep and goat milk was measured. The amount of bisphenol in cow's milk was higher than the other two species ( Colón, Rascón, Hejji, Azzouz, & Ballesteros, 2021 ). On the contrary, goat's milk yogurts were more than cow's milk yogurts.…”

“…On the contrary, goat's milk yogurts were more than cow's milk yogurts. Of course, it is worth mentioning that factors such as production process equipment, type of packaging and environmental pollution can play a role ( Colón et al, 2021 ).…”

“…Only in the Casajuana/2004, Colon/2021, and Chakraborty/2022studies, BPA was measured with GC–MS ( Casajuana and Lacorte, 2004 , Chakraborty et al, 2022 , Colón et al, 2021 ). Using the GC–MS method to measure bisphenol A in food matrices requires derivatization.…”

“…Phenolic compounds need derivatization by measuring with GC–MS. Derivatization increases the sensitivity of the measurement method and avoids reporting false positives ( Colón et al, 2021 ). In the Colón/2021 study, derivatization was done with N,O-bis(trimethylsilyl)trifluoroacetamide and trimethylchlorosilane ( Colón et al, 2021 ).…”

“…Derivatization increases the sensitivity of the measurement method and avoids reporting false positives ( Colón et al, 2021 ). In the Colón/2021 study, derivatization was done with N,O-bis(trimethylsilyl)trifluoroacetamide and trimethylchlorosilane ( Colón et al, 2021 ). Bromoacetonitrile (BAN) is also used for derivatization ( Szyrwińska, Kołodziejczak, Rykowska, Wasiak, & Lulek, 2007 ).…”