A Review on Recent Sensing Methods for Determining Formaldehyde in Agri-Food Chain: A Comparison with the Conventional Analytical Approaches

Abstract

Formaldehyde, the simplest molecule of the aldehyde group, is a gaseous compound at room temperature and pressure, is colorless, and has a strong, pungent odor. It is soluble in water, ethanol, and diethyl ether and is used in solution or polymerized form. Its maximum daily dosage established by the EPA is 0.2 μg g−1 of body weight whereas that established by the WHO is between 1.5 and 14 mg g−1: it is in category 1A of carcinogens by IARC. From an analytical point of view, formaldehyde is traditionally analyzed by HPLC with UV-Vis detection. Nowadays, the need to analyze this compound quickly and in situ is increasing. This work proposes a critical review of methods for analyzing formaldehyde in food using sensing methods. A search carried out on the Scopus database documented more than 50 papers published in the last 5 years. The increase in interest in the recognition of the presence of formaldehyde in food has occurred in recent years, above all due to an awareness of the damage it can cause to human health. This paper focuses on some new sensors by analyzing their performance and comparing them with various no-sensing methods but focusing on the determination of formaldehyde in food products. The sensors reported are of various types, but they all share a good LOD, good accuracy, and a reduced analysis time. Some of them are also biodegradable and others have a very low cost, many are portable and easy to use, therefore usable for the recognition of food adulterations on site.

NiCo‐LDH coupled with 2D ZIF‐derived Co nitrogen doped carbon nanosheet arrays as a self‐supporting electrocatalyst for detection of formaldehyde

“…However, formaldehyde is a recognised carcinogen and long-term exposure to formaldehyde in the environment can lead to vomiting, coma and even leukaemia and cancer. [1] Due to its antimicrobial, preservative and bleaching properties, formaldehyde is susceptible to illegal use as a food additive. [2,3] For this reason, the United States Environmental Protection Agency (USEPA) has set an Acceptable Daily Intake (ADI) for formaldehyde at 0.2 mg/kg body weight.…”

“…Formaldehyde is a common organic compound with a pungent odour and strong volatility. However, formaldehyde is a recognised carcinogen and long‐term exposure to formaldehyde in the environment can lead to vomiting, coma and even leukaemia and cancer [1] . Due to its antimicrobial, preservative and bleaching properties, formaldehyde is susceptible to illegal use as a food additive [2,3] .…”

Bimetallic Au and Pd Nanoparticles Modified WO3 Nanosheets for Enhancing the Sensitivity and Selectivity of Formaldehyde Assessment in Aquatic Products

“…At present, there are many methods to detect formaldehyde in food, such as fluorescence method, 9 gas chromatography mass spectrometry (GC−MS), 10 spectrophotometry, 11 high-per-formance liquid chromatography (HPLC) spectrometry, 12 and biosensor method. 13 These conventional detection methods either rely on specialized personnel or large instruments, which are time-consuming, labor-intensive, and costly. 14 However, metal oxide semiconductor (MOS)-based gas sensors have the advantages of low price, simplicity of operation, high stability, and fast response and recovery, which have led to their widespread use for the rapid and efficient detection of toxic and volatile gas compounds.…”

“…At present, there are many methods to detect formaldehyde in food, such as fluorescence method, gas chromatography mass spectrometry (GC–MS), spectrophotometry, high-performance liquid chromatography (HPLC) spectrometry, and biosensor method . These conventional detection methods either rely on specialized personnel or large instruments, which are time-consuming, labor-intensive, and costly .…”

Formaldehyde Sensing Using Tapered U-Shape Plastic Optical Fiber Coated With Zinc Oxide Nanorods

“…The majority of us use formaldehydecontaining products on a daily basis. It is found in a broad number of items, including fabrics, foods, disinfectants, photo processing chemicals, preservatives, and even beauty products [2][3][4]. Formaldehyde is a highly toxic volatile organic compound (VOC) that becomes dangerous to humans when concentrations are above a certain level.…”