Intensified microbiological sampling may only result in modest decreases in foodborne illness while increasing financial costs and food waste, researchers suggested in a new study published in the International Journal of Food Microbiology.

The researchers—affiliated with the Aristotle University of Thessaloniki, Greece and the Statens Serum Institute, Denmark—applied a quantitative microbiological risk assessment (QMRA) framework to evaluate the broader impacts of microbiological sampling plans, highlighting important trade-offs between public health benefits, economic costs, and environmental burdens in food safety systems.

Arguments for Risk-Based, “One Health” Frameworks Over “Zero-Risk”

The findings echo another peer-reviewed article published in Frontiers in Science in March, which argued that achieving “zero risk” in food safety is neither feasible nor desirable, and that controls based on overly sensitive detection methods and focused on single outcomes may introduce unintended environmental and economic consequences.

Both articles advocate for the adoption of risk-based frameworks that consider sustainability trade-offs and view food safety within the broader “One Health” context, which recognizes the interconnected nature of human, animal, and environmental health. The present study provides an example of such a framework.

QMRA Framework Enables Risk-Benefit Evaluation

In the present study, the researchers developed a modular, farm-to-fork QMRA model encompassing the production, processing, and consumption stages, using Salmonella in chicken patties as a case study. The model integrated exposure assessment, dose-response relationships, and a sampling algorithm to estimate illness risk under different testing intensities.

Importantly, the framework also quantified economic outcomes, such as testing costs and product losses, alongside environmental impacts, including food waste from rejected batches. This enabled a unified comparison of sampling strategies across multiple dimensions.

Diminishing Returns from Increased Sampling

Across modeled scenarios, increasing sampling intensity resulted in limited public health gains. Within typical regulatory ranges, additional sampling reduced predicted illness risk only marginally, while higher sampling levels yielded small absolute reductions in cases relative to the associated costs.

Specifically, the results showed that increased sampling stringency within a feasible range (sample sizes up to ten) leads to less than 1 percent reduction in the probability of foodborne illness. Although sample sizes greater than 20 inferred a greater reduction in risk, it was still very low, at less than 5 percent.

As processing environments have improved and baseline contamination levels have declined, the effectiveness of end-product sampling as a primary risk control measure has diminished, the researchers suggested.

Economic and Environmental Trade-Offs

On the other hand, the study showed that intensified sampling increased operational costs and food waste in near-linear proportion to sampling stringency. For example, following the EU-standard sampling plan reduced an estimated 22 cases per 100,000 consumers but incurred approximately €540,000 in combined testing and product loss costs.

Overall, testing expenses, batch rejection, and contaminated product disposal associated with intensified sampling were not proportional to reductions in risk.

These findings underscore the need to evaluate food safety interventions beyond microbiological outcomes alone, especially as sustainability and resource efficiency become higher priorities across the food sector.

Sampling More Valuable in High-Risk Facilities

Importantly, the findings showed that the effectiveness of intensified sampling varied significantly based on production factors. Sampling provided greater benefit in systems with higher contamination prevalence, where the detection of unsafe batches was more likely. In contrast, in facilities with strong pathogen control and low levels of contamination, additional sampling offered minimal incremental value.

Implications for Industry and Wider QMRA Adoption

The authors concluded that microbiological sampling is more appropriately positioned as a verification tool within risk-based food safety management systems, rather than a primary intervention. They suggested that sampling intensity could be optimized based on facility performance, reserving more frequent testing for higher-risk operations.

The model supports integration into broader risk management and decision-making frameworks. Other than the outcome metrics it currently estimates, such as the probability of illness and economic burden of disease, the model's structure allows for extension to include additional metrics, such as Disability-Adjusted Life Years (DALYs), carbon footprint, or stakeholder preferences.

Therefore, the researchers believe their model could meaningfully contribute to multi-criteria evaluations of food safety interventions within a One Health context. It could provide a structured basis for regulators and industry to quantify trade-offs between food safety and resource efficiency, and support evidence-based revision of microbiological criteria.