For the Love of Food! Analysis Solutions For PFAS, Organic Contaminants, and Heavy Metals
Learn about per- and polyfluoroalkyl substances (PFAS), organic contaminants and heavy metals, and understand the importance of monitoring and analyzing them for ensuring food and environmental safety.
Per- & Polyfluoroalkyl Substances (PFAS)
Per-and polyfluoroalkyl substances (PFAS) are a group of persistent and harmful chemicals that can be commonly found in the environment globally. These anthropogenic chemicals can come from various sources such as manufacturing, industrial applications, food contact materials and consumer products, and eventually end up and accumulate in the water, soil and living organisms. With concerns rising quickly about the health risks associated with PFAS exposure, it is important to ensure proper monitoring of these chemicals.
Organic Contaminants
Demands regarding the analysis of contaminants that are mixed in or adhered to products are increasing for food and chemical manufacturers and inspection agencies which are consigned inspections. This increase in demands has drawn attention to energy dispersive X-ray fluorescence spectrometers (EDX) which are suited to analyzing inorganic elements such as metals and to Fourier transform infrared spectrophotometers (FTIR) which are optimal for the analysis of organic substances such as polymeric compounds. Cases where one sample is analyzed using both instruments are increasing as well.
Heavy Metals
Heavy metals are naturally occurring elements or metalloids that can be toxic to both humans and the environment when present in high concentrations. While essential as nutrients in trace amounts, these substances are classified as pollutants when found in excessive quantities, particularly if introduced unintentionally. Sources of heavy metals include but are not limited to agricultural, pharmaceutical and mining effluents. Common examples encompass iron, copper, zinc and others.
Heavy metals such as cadmium, chromium and lead are natural components of the earth’s crust and are typically present in our environment at various concentration levels. They enter the human body via food, drink and air. Some of these heavy metals, the so-called trace elements such as chromium, iron, cobalt, copper, manganese, zinc and tin are in low concentrations essential to the human body, as they are important for the metabolism.
At higher concentrations however, they are toxic and harmful to humans. Heavy metal poisoning may occur from contamination of drinking water from lead transfer pipes, air contamination from industrial emissions or ingestion via the food chain in the form of contaminated vegetables, meat and fish.
Determination of heavy metals can be done using Atomic Absorption Spectroscopy (AAS), Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). ISO 17294-2:2016 specifies a method for the determination of 62 elements in drinking water, surface water, ground water, wastewater and eluates using ICP-MS spectrometry.
A Deep Dive Into PFAS Analysis in Food Samples
Per- and Polyfluoroalkyl Substances (PFAS) is the collective name for a chemical group of organic fluorinated compounds, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are representative compounds of PFAS. They have been used water repellents, surface treatment agents, fire extinguishers, and coatings.
PFAS are persistent and bioaccumulative in the environment because of their stable structure and known that they are present in a wide range of environmental water and wildlife. Due to concerns about human exposure through diet, studies on the status of food contamination by PFAS are being conducted in various countries.
Herein, Shimadzu presents a workflow solution on the quantitative analysis method for 40 PFAS compounds in foods with 2 SPE cartridges. An LC-MS method was developed to analyze 40 PFAS compounds within 15 mins.
General Challenges in PFAS Analysis
Sampling for PFAS without contaminating the samples can be challenging due to the prevalence of these chemicals in many consumer products and standard sampling equipment. To avoid the possibility of cross-contamination, lab analyst should select their personal protective equipment (PPE) carefully preparing samples for PFAS analysis.
PFAS can also be present in the water and/or cleaning agents used in decontamination processes. When cleaning sampling equipment, lab personnel should avoid using decontamination soaps containing fluorosurfactants such as Decon 90. Water from an on-site well is also a potential source of contamination.
Alconox® and/or Liquinox® are recommended for decontamination processes as well as potable water from a municipal drinking water supply. Sampling equipment should be scrubbed using a polyethylene or PVC brush and flushed with water before the next use. Water should be always verified as “PFAS-free” before it is used for field and decontamination blanks and decontamination processes.
Some Best Practices in PFAS Analysis
Stock solutions should be prepared and stored in PFAS-free high-density polyethylene (HDPE) or polypropylene (PP) containers with lined or unlined HDPE or polypropylene caps. Do not store samples in containers made of glass or low-density polyethylene (LDPE) materials. PFAS can adsorb to glass, especially when the chemicals are stored in a glass container for long periods of time.
Stability of the standards solutions for a predetermined interval of time when stored under recommended conditions is a relevant parameter for ensuring the quality of the analysis.
When it comes to sample preparation and injection, PFAS-free tubing should be used for loading samples into the cartridges. If automatic sample extractors are employed for this step of the analysis, checking with the manufacturer is strongly recommended to identify all components made of PFTE and replace them when feasible.
Once samples are ready for analysis, they may sit in the autosampler tray for extended periods of time. In these situations, some PFAS compounds may settle, precipitate or adsorb on the surface. It is important to remember to mix the extract/sample before (re)injection. Vortexing the solution before injection ensures a homogenous solution and optimum results.
Shimadzu Digital Classrooms: Register To Learn All About Contaminant Analysis in Food
Join us for an immersive session delving into food safety analysis, covering three vital areas: organic contaminants identification, elemental analysis, and the pressing issue of PFAS.
In this comprehensive session, our dedicated expert, Qi An, will kick off the session by introducing Shimadzu’s innovative FTIR analysis workflow that identifies organic contaminants in just seconds to boost your productivity at work. Besides, explore the flexibility offered by various FTIR configurations tailored to analyze different contaminant sizes and uncover the capabilities of Shimadzu’s LabSolutions IR software and the Contaminant Library for robust data analysis.
Following that, our seasoned expert Mangesh will delve into elemental analysis, demonstrating how Shimadzu’s ICP-MS is ushering in a new era without compromise. Whether it's the nourishing minerals in milk or the potentially harmful elements in fruit juice, Shimadzu's ICPMS accurately quantifies both micro and macro elements present in our daily diet.
Lastly, our specialist, Elton, will address the emerging food safety concern of PFAS in food. Gain valuable insights into the evolving regulatory landscape, explore the current EFSA and FDA guidelines, and discover measures to manage this complex issue. Specifically, Elton will introduce how Shimadzu's LC-MS/MS solutions can effectively address PFAS concerns in food.
Learning Objectives
- Learn how Shimadzu’s FTIR analysis can enable quick characterization of organic contaminants.
- Understand how LabSolutions IR software can effectively translate spectral data into actionable insights.
- Discover the capabilities of Shimadzu’s ICP-MS to detect harmful elements in food.
- Explore how Shimadzu’s LC-MS/MS solutions can effectively address PFAS concerns in food.
For more, explore our Resource Library and Digital Classrooms. In addition, stay connected with us here.