What is a safe level of acrylamide?

Acrylamide, a chemical that forms naturally in starchy foods cooked at high temperatures, is classified as a probable human carcinogen based on animal studies. This classification raises a critical public health question: what is a safe level of acrylamide for human consumption?

Quick Summary

Because acrylamide is a genotoxic carcinogen, no 'safe' level can be established. Regulatory bodies like EFSA and WHO use a Margin of Exposure to assess risk and recommend minimizing intake. This article details expert findings, key dietary sources, and consumer strategies for reduction.

Key Points

• No Safe Level Defined: Due to its genotoxic and carcinogenic nature, regulatory bodies cannot establish a traditional 'safe' or tolerable daily intake (TDI) for acrylamide.

• Risk Assessed by MOE: The Margin of Exposure (MOE) approach is used to evaluate health concern by comparing human dietary exposure to doses affecting animals.

• Precautionary Principle: The guiding principle is to reduce acrylamide levels to be 'as low as reasonably achievable' (ALARA) through both consumer and industry actions.

• Primary Dietary Sources: Starchy foods cooked at high temperatures, including fried potato products, biscuits, cereals, and coffee, are the main sources of dietary acrylamide.

• Reduce Excessive Browning: A key consumer mitigation strategy is to cook foods to a lighter, golden color rather than over-browning or burning them.

• Children at Higher Risk: Young children typically have higher acrylamide exposure on a body weight basis and are considered a more sensitive population group.

• Soaking and Boiling Help: Simple preparation steps like soaking potatoes or choosing boiling over frying can significantly reduce acrylamide formation in home cooking.

The Challenge of Defining a 'Safe' Level

Unlike many other food contaminants, acrylamide's classification as a genotoxic carcinogen presents a unique challenge for risk assessment. A genotoxic substance is one that can damage DNA, which is a key step in the development of cancer. For such substances, regulatory bodies like the European Food Safety Authority (EFSA) and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) have concluded that it is not possible to establish a definitive Tolerable Daily Intake (TDI). This is because even very low levels of a genotoxic carcinogen are theoretically capable of causing damage, meaning any level of exposure could pose a risk.

Instead of a 'safe' level, a precautionary principle is applied, focusing on reducing exposure to levels that are "as low as reasonably achievable" (ALARA). This approach prioritizes minimizing the chemical's presence in food rather than setting a specific threshold for safety.

Understanding Risk Assessments: Margin of Exposure

To assess the potential health risk posed by acrylamide, health agencies use a tool called the Margin of Exposure (MOE). The MOE approach compares the estimated dietary intake in humans with benchmark dose levels (BMDL10) observed in animal studies. The BMDL10 represents a dose that causes a small but measurable increase in adverse effects, such as tumor incidence in laboratory animals.

• How MOE is interpreted: A higher MOE indicates a lower health concern. For genotoxic carcinogens, EFSA states that an MOE of 10,000 or higher is of low concern for public health. However, typical MOE values for acrylamide in human diets are significantly lower, indicating a potential public health concern.
• Children at higher risk: Studies have consistently found that young children tend to have a higher dietary intake of acrylamide on a body weight basis than adults. This is due to their smaller body size combined with higher relative food consumption, and a diet often richer in foods known to contain acrylamide, such as potato products. This results in lower MOE values for children, highlighting a greater concern for this population group.

Sources of Acrylamide Exposure

Acrylamide is primarily formed from the reaction between asparagine (an amino acid) and reducing sugars during high-temperature cooking processes like frying, baking, roasting, and toasting. Common food sources contributing to dietary exposure include:

• Potato products: French fries, potato crisps, and roasted potatoes typically contain some of the highest levels of acrylamide. Soaking potato slices before cooking can help remove some of the sugars that contribute to its formation.
• Cereal-based products: This includes biscuits, cookies, crackers, breakfast cereals, and toasted bread.
• Coffee: Roasted coffee beans and instant coffee can also contain acrylamide.
• Other foods: Processed snacks, some baked goods, and even certain traditional foods can be sources, depending on cooking methods.

Mitigation Measures and Reducing Intake

Consumer-level Actions

Since no single 'safe' level can be defined, the most effective strategy is to minimize your overall exposure. Small adjustments to your cooking habits can help reduce acrylamide formation significantly. Key recommendations include:

• Go for 'Golden Yellow': Aim for a lighter, golden color when frying, baking, or toasting starchy foods rather than over-browning or burning them. Colour charts for fries are available from some suppliers to help ensure consistency.
• Follow Packaging Instructions: When cooking pre-packaged foods like chips and roast potatoes, adhere to the manufacturer's cooking instructions, as many have optimized their processes to minimize acrylamide levels.
• Soak Potatoes: Before frying or roasting potatoes, soak the raw slices in water for 15-30 minutes. This helps to remove some of the free sugars and reduces acrylamide formation.
• Choose Lower-Temp Methods: Opt for boiling and steaming whenever possible, as these methods do not produce acrylamide.
• Maintain Cooking Equipment: Regularly cleaning fryers and changing oil helps prevent contamination from burnt food particles.

Industry-level Efforts

The food industry has been actively working to reduce acrylamide levels since its discovery in food in 2002. Mitigation strategies include:

• Raw Material Selection: Choosing potato cultivars and cereal grains with naturally lower levels of asparagine and reducing sugars.
• Process Optimization: Adjusting cooking times and temperatures to reduce acrylamide formation while maintaining desired taste and texture.
• Enzyme Use: Applying the enzyme asparaginase during food processing to break down asparagine before it can react to form acrylamide.

Acrylamide Regulation: EU Benchmark Levels (BMLs)

To drive industry-wide reduction efforts, the European Union established benchmark levels (BMLs) for various food categories through Regulation (EU) 2017/2158. It is important to understand the distinction between BMLs and legal safety limits. A BML is a performance indicator for food businesses to measure the effectiveness of their mitigation efforts. Exceeding a BML is not illegal and does not necessarily mean a product is unsafe, but it does prompt an investigation to ensure mitigation measures are being properly implemented. This contrasts with legal maximum limits, which carry enforcement consequences if breached.

Comparing Regulatory Approaches

Feature	Benchmark Levels (BMLs, EU Regulation)	Tolerable Daily Intake (TDI)
Purpose	Performance indicators for industry to reduce levels.	Maximum daily exposure a person can ingest without adverse health effects.
Scientific Basis	Risk assessment via Margin of Exposure (MOE) for a genotoxic carcinogen.	Traditionally used for substances with a defined dose-response threshold.
Enforcement	Not a legal maximum limit; triggers investigation into mitigation practices.	A legal maximum limit that, if exceeded, implies an unacceptable health risk.
Underlying Principle	ALARA ('As Low As Reasonably Achievable') for genotoxic substances.	Based on the assumption of a no-effect threshold for non-genotoxic substances.

Conclusion: A Precautionary Approach to Acrylamide

While science confirms that no specific "safe" level of dietary acrylamide can be set, expert health bodies worldwide agree on the need for reducing exposure as a precautionary measure. For consumers, this means adopting simple cooking and food preparation techniques that minimize the formation of the chemical, such as reducing browning and opting for boiling or steaming where possible. For the food industry, this involves ongoing innovation and adherence to best practices to lower acrylamide levels in processed products. By understanding the risks and taking practical steps, both consumers and manufacturers can work towards minimizing dietary acrylamide intake and promoting public health. For more detailed information on mitigation strategies, consult the Codex Alimentarius Code of Practice for the Reduction of Acrylamide in Foods.

Frequently Asked Questions

Why can't scientists set a safe daily intake for acrylamide?

Acrylamide is a genotoxic carcinogen, meaning it can damage DNA. For substances with this property, scientists and regulatory bodies cannot establish a truly 'safe' level because even minimal exposure is theoretically capable of causing harm.

What is the Margin of Exposure (MOE) and what does it mean for acrylamide?

The MOE is a risk assessment tool that compares human dietary exposure to levels that cause adverse effects in animals. For acrylamide, current MOE values suggest a public health concern, prompting authorities to recommend reduced intake.

Which foods are the biggest dietary sources of acrylamide?

The highest levels of acrylamide are typically found in starchy foods cooked at high temperatures, such as potato crisps, French fries, roasted coffee, toasted bread, and certain biscuits and crackers.

Is it better to boil or fry foods to avoid acrylamide?

Boiling and steaming do not produce acrylamide, making them preferable cooking methods from a food safety perspective when compared to high-temperature methods like frying or roasting.

What are the EU Benchmark Levels (BMLs) for acrylamide in food?

BMLs are performance indicators set by the EU to guide food businesses in minimizing acrylamide levels in products like coffee, cereals, and potato crisps. They are not legal maximum limits but trigger investigations when exceeded.

How can I reduce my acrylamide intake at home?

To reduce intake at home, avoid over-browning food, follow cooking instructions on packaged products, soak raw potato slices in water before cooking, and choose boiling or steaming over frying.

Are children more at risk from acrylamide exposure?

Yes, on a body weight basis, children are typically more exposed to acrylamide than adults. This is due to their smaller size and dietary preferences, which means they consume a higher amount relative to their body weight.