Trace Contaminants & Residues – Packaging

July 27, 2020 - Trace Contaminants & Residues - Elisabeth Anderson, Joe Zagorski

Updated: June 1, 2026

As we’ve discussed in prior posts, trace contaminants and residues can make their way into our food system. In this post, we’ll explore the important role packaging plays in protecting our food, how food-contact materials are evaluated for safety, and how our understanding of packaging materials continues to evolve.

Top Takeaways:

Packaging plays an essential role in keeping food safe by protecting products during processing, transportation, storage, and use.
Food-contact materials are regulated to ensure they meet safety standards before use.
Small amounts of substances from packaging may migrate into food, but the presence of a substance does not automatically mean it poses a health risk.

What is a trace contaminant or residue?

Trace contaminants and residues are very small amounts of substances that may be found in food, beverages, or the materials that come into contact with them.

These can include many different substances, such as:

naturally occurring minerals
microorganisms
agricultural residues
substances from processing or packaging materials

Importantly, detecting a substance does not automatically mean it is harmful. Scientists evaluate whether the amount present could contribute to meaningful exposure and potential health effects.

What does packaging do?

Packaging plays a critical role in our food system.

Before food reaches our tables, it often goes through many steps, including harvesting, processing, storage, transportation, and distribution. Packaging helps protect food throughout this process.

Food packaging can help:

prevent contamination
reduce food waste
preserve freshness and quality
extend shelf life
allow food to be safely transported

Without appropriate packaging, many foods would spoil faster, become more easily contaminated, or be unable to reach consumers safely.

Who regulates packaging and food-grade storage containers?

In the United States, the Food and Drug Administration (FDA) regulates materials intended to come into contact with food.

Food-contact materials must meet safety requirements and follow Current Good Manufacturing Practices (CGMP), which help ensure products remain safe throughout manufacturing, packaging, and distribution.

Manufacturers must evaluate food-contact materials to ensure they are appropriate for their intended use.

In recent years, regulatory approaches have continued to evolve as researchers develop improved methods for detecting substances and evaluating exposure.

What types of packaging materials are commonly used?

There are many types of food-contact materials used throughout the food system, including:

plastics
cardboard and paper products
glass
metals
wood
recycled materials approved for food-contact use

The best packaging choice depends on the specific food, how it will be stored, how long it needs to last, and how it will be transported.

How can packaging prevent contamination?

Packaging creates a protective barrier between food and the outside environment.

It helps prevent exposure to substances and microorganisms that could reduce food quality or potentially cause illness.

Manufacturers use different packaging technologies depending on the product. Some packaging is designed to control moisture, limit oxygen exposure, prevent microbial growth, or maintain freshness.

The goal is to keep food safe from the time it is produced until it reaches your plate.

Can packaging leave trace residues in food?

Some substances from packaging materials can migrate into food at very small levels. The process is known as migration.

Because migration can occur, manufacturers must consider:

the packaging material
the type of food it comes in contact with
storage conditions
temperature
duration of contact

Food-contact safety evaluations consider realistic exposure scenarios to ensure materials can be used safely.

The important question is not simply whether something can be detected, but whether the amount present is high enough to pose a risk.

What are PFAS compounds in packaging?

Pre- and polyfluoroalkyl substances (PFAS) in packaging refer to a large group of thousands of compounds known for their ability to resist oil, water, heat, and stains.

Because of these properties, certain PFAS were historically used in some food packaging materials, including grease-resistant wrappers, microwave popcorn bags, and some take-out containers.

However, scientific understanding of PFAS and their environmental persistence has continued to evolve, leading researchers, regulators, and manufacturers to reassess their use.

In February 2024, the U.S. Food and Drug Administration (FDA) announced that grease-proofing substances containing PFAS were no longer being sold by manufacturers for food-contact use in the U.S. market. These materials were removed following a voluntary phase-out process that began in 2020.

In January 2025, the FDA determined that 35 food contact notifications related to PFAS-containing substances were “no longer effective” because manufacturers had stopped producing, supplying, or using those materials.

Regulatory approaches continue to evolve globally, with several U.S. states and the European Union introducing additional restrictions on intentionally added PFAS in food packaging.

What about microplastics and nanoplastics from packaging?

Research shows that microplastics and nanoplastics can migrate from some food and beverage packaging into products we consume.

Current research has not established that these small particles cause harm to human health at the levels people are typically exposed to; however, this remains an active and evolving area of scientific study.

As researchers improve detection methods and better understand exposure, regulators will be able to continue evaluating potential risks and determine whether additional guidance is needed.

How is the safety of packaging residues evaluated?

Scientists evaluate packaging residues by looking at both the substance itself and the amount to which people may actually be exposed.

This includes:

toxicological data
how much of the substance may migrate
expected dietary exposure
how often exposure may occur

Many residues are measured in parts per million (ppm), parts per billion (ppb), or even smaller amounts.

A part per million is a tiny measurement representing one part in a whole entity of one million parts. For example, there are more than 10 million bricks in the Empire State building, that means 10 bricks is 1 part per million (ppm).

Ted Ed put together a fantastic video helping to explain parts per million.

When we talk about parts per billion (ppb) or parts per trillion (ppt), it’s an even smaller number. While billion or trillion sounds like it would be a larger quantity, it’s a much small quantity by a much larger magnitude.

For example:
1 ppm = 0.000001 of 1
1 ppb = 0.000000001 of 1
1 ppt = 0.000000000001 of 1

Modern technology allows scientists to detect incredibly small amounts of substances, but detection alone does not determine risk. Safety depends on exposure.

The good news.

Packaging plays an essential role in maintaining a safe and reliable food supply.

As science advances, researchers continue improving our ability to detect substances, understand exposure, and evaluate potential risks. Manufacturers and regulators use this evolving knowledge to update materials, improve practices, and ensure food packaging continues to safely protect the products we rely on every day.

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