Methodology for risk-based monitoring of contaminants in food - A case study in cereals and fish.

In this study, a methodology was developed that can be used as input for risk-based monitoring plans for chemical contaminants in food products. The novel methodology was applied to a case study in which cereals and fish were evaluated simultaneously for the possible presence of mycotoxins and heavy metals. The methodology was based on hazard quotients that were estimated by dividing the daily intake - using concentrations of the contaminants in the different food products and consumption of the respective products combined per product group - by the health based guidance value (HBGV) or reference points used for assessing potential health concerns (RPHC). The most relevant hazard-product combinations were further ranked based on the volume of import of the ingredients, per import country and a defined contaminant prevalence level per country. For fish, the hazard quotients were around ten times lower compared to the highest hazard quotients in cereals. Consumption of molluscs, mackerel-type fish and herring-type fish contaminated with mercury contributed most to the HBGV or RPHC. The top 25 hazard-product combinations for various age groups included: aflatoxin B1 in combination with wheat, rice (products), maize (products), and pasta, zearalenone in combination with wheat (products), T2/HT2-toxin in combination with rice (products), and DON in combination with wheat (products). The methodology presented showed to be useful in identifying the most relevant hazard-food-age group combinations and the most relevant import countries linked to these that should be included in the monitoring. As such, the method can help risk managers in establishing risk-based monitoring programs.

Chemical food safety hazards in circular food systems: a review.

Food production has increasingly become effective but not necessarily sustainable. Transitioning toward circular production systems aiming to minimize waste and reuse materials is one of the means to obtain a more sustainable food production system. However, such a circular food production system can also lead to the accumulation and recirculation of chemical hazards. A literature review was performed to identify potential chemical hazards related to the use of edible and non-edible resources in agriculture and horticulture, and edible plant and animal by-products in feed production. The review revealed that limited information was available on the chemical hazards that could occur when reusing crop residues in circular agriculture. Frequently mentioned hazards present in edible and non-edible resources are heavy metals, process and environmental contaminants, pesticides and pharmaceuticals. For feed, natural toxins and pharmaceutical residues are of potential concern. Studies, furthermore, indicated that plants are capable of taking up chemical hazards when grown on contaminated soil. The presence of chemical hazards in manure, sewage sludge, crop residues, and animal by-products may lead to accumulation in a circular food production system. Therefore, it is relevant to identify these hazards prior to application in food production and, if needed, take precautionary measures to prevent food safety risks.

Alternative proteins for meat and dairy replacers: Food safety and future trends.

Traditionally, meat and dairy products have been important protein sources in the human diet. Consumers are eating more plant-based proteins, which is reflected in current market trends. Assessing how alternative proteins are processed and their impact on food safety helps realize market opportunities while ensuring food safety. In this review, an analysis of the food safety hazards, along with current industry trends and processing methods associated with alternative proteins for meat and dairy products for the European Union market is described. Understanding the effects of processing and safety alternative proteins is paramount to ensuring food safety and understanding the risks to consumers. However, the data here is limited. With the expected further increase in protein alternatives in consumers' diets, the risk of food allergens is apparent. The occurrence of processing contaminants in plant-based alternatives may occur, along with anti-nutritional compounds, which interfere with the absorption of nutrients. Further, typical food safety hazards related to the plant, the product itself, or processing are relevant. Although hazards in insects and seaweed are being addressed, other protein alternatives like cultured meat and SCPs warrant attention. Our findings can aid industry and governmental authorities in understanding current trends and prioritizing hazards for future monitoring.

Review of food safety hazards in circular food systems in Europe.

European food production systems have become very efficient in terms of high yield, quality and safety. However, these production systems are not sustainable since, amongst other reasons, a significant proportion of the production is wasted or lost in the supply chain. One of the strategies of the European Union is to achieve climate neutrality by moving towards a circular economy with better waste management. This includes, reducing food waste and losses, and reusing or recycling by-products of the food and feed production systems. A circular economy would greatly improve the sustainability of the European food systems, but attention must be paid to the emergence of (new) food safety hazards. New or not well-known hazards can occur because by-products are reintroduced into the system or new processing steps are used for recycling, and/or known hazards can accumulate in the food production chain due to the reuse of (by-)products. This review addresses food safety hazards in the circular biobased economy, covering the domains of plant production, animal production, aquaculture, and packaging. Instead of an exhaustive list of all potential hazards, example cases of circular food production systems are given, highlighting the known and potential emerging food safety hazards. Current literature covering emerging food safety hazards in the circular economy shows to be limited. Therefore, more research is needed to identify food safety hazards, to measure the accumulation and the distribution of such hazards in the food and feed production systems, and to develop control and mitigation strategies. We advocate a food safety by design approach.

Methods to perform risk-based inspections of food companies.

Risk-based monitoring programs are increasingly applied for cost-effective monitoring of food safety. Such programs ideally consist of three steps: risk-ranking, risk-based inspections, and cost-effective monitoring. Various methods have been described to perform the first step of risk-based monitoring. However, once the risk-ranking has been completed, identifying the hazard-food combinations to monitor, the frequency of inspection needs to be established based on a prioritization of food business operators (FBOs). The aim of this paper is to provide an overview of methods available for risk-based inspections. Literature shows that FBO's food safety compliance can be assessed based on company size, historical monitoring data, and socio-economic factors influencing compliance behavior. Non-compliance can either be intentional or unintentional. The latter can be assessed by evaluating the food safety culture of a company. Various models-ranging from qualitative (e.g., focus groups) to quantitative (e.g., scoring)-can be used for this purpose. These models usually include an evaluation of the organizational structure (e.g., management control, communication, commitment), the technical food safety environment (e.g., hygienic design, zoning), and employee characteristics (e.g., knowledge, risk awareness). Intentional non-compliance can be assessed using food fraud vulnerability tools. These tools incorporate factors influencing the likelihood of food fraud at the company, that is, opportunity, motivation, and (lack of) control measures. The literature indicates that either self-assessment tools or risk matrices are applied. There is no global consensus on the methods to apply for risk-based inspections. Depending on time and budget available as well as preferred output, one of the presented methods may be applied for prioritizing FBOs.

Critical review of methods for risk ranking of food-related hazards, based on risks for human health.

This study aimed to critically review methods for ranking risks related to food safety and dietary hazards on the basis of their anticipated human health impacts. A literature review was performed to identify and characterize methods for risk ranking from the fields of food, environmental science and socio-economic sciences. The review used a predefined search protocol, and covered the bibliographic databases Scopus, CAB Abstracts, Web of Sciences, and PubMed over the period 1993-2013. All references deemed relevant, on the basis of predefined evaluation criteria, were included in the review, and the risk ranking method characterized. The methods were then clustered-based on their characteristics-into eleven method categories. These categories included: risk assessment, comparative risk assessment, risk ratio method, scoring method, cost of illness, health adjusted life years (HALY), multi-criteria decision analysis, risk matrix, flow charts/decision trees, stated preference techniques and expert synthesis. Method categories were described by their characteristics, weaknesses and strengths, data resources, and fields of applications. It was concluded there is no single best method for risk ranking. The method to be used should be selected on the basis of risk manager/assessor requirements, data availability, and the characteristics of the method. Recommendations for future use and application are provided.

Food Safety Crisis Management-A Comparison between Germany and the Netherlands.

In order to prevent food safety incidents from becoming a crisis, a good crisis management structure is essential. The aim of the current study was to compare and evaluate the national food incident response plans of 2 neighboring EU Member States: Germany and the Netherlands. This revealed that the structure of these plans is comparable, starting with initial alerting, assessment of the problem, upscaling, an execution phase and finally an evaluation of the crisis management. However, the German communication structure is more complex than the Dutch one and cross-border communication between both countries is currently limited. In general, the presence of national response plans does not guarantee a good and swift response to a food safety incident as this is often hampered by difficulties in tracing the source of the problem as well as difficulties in communication between organizations involved in crisis management. A timely detection can be improved through the development of fast screening and detecting systems and through combining various data sources using computer software systems. Mutual cooperation and communication can be improved through joint exercises or projects. This will help to streamline communication toward consumers and trade partners. Such communication should be transparent relaying not only the facts but also the uncertainties in a crisis in order to gain consumer trust and safeguard international trade.

Overview of Food Safety Hazards in the European Dairy Supply Chain.

Monitoring of dairy products should preferably focus on the most relevant food safety hazards in the dairy supply chain. For this purpose, the possible presence of microbiological, chemical, and physical hazards as well as trends in the dairy supply chain that may affect their presence were assessed. A literature review was combined with available data from EFSA, RASFF, and the Dutch monitoring program on chemical hazards as well as expert information. This study revealed that microbiological hazards are encountered more frequently in dairy products than chemical and physical hazards. Listeria monocytogenes, Staphylococcus aureus, Salmonella, and human pathogenic Escherichia coli were identified as the most important microbiological hazards in dairy products. Soft and semisoft cheeses are most frequently associated with L. monocytogenes and S. aureus enterotoxins, whereas raw milk is most frequently associated with human pathogenic E. coli and Campylobacter spp., Cronobacter spp., and Salmonella spp. are the microbiological hazards of most concern in powdered infant formula. Based on literature, monitoring, and RASFF data, the most relevant chemical hazards in dairy products are aflatoxin M1 , dioxins, and dioxin-like compounds and residues of veterinary drugs. Chemical hazards primarily occur at the dairy farm and may accumulate during further processing. The most relevant physical hazards are metal, glass, and plastic particles introduced during processing. Analysis of trends in the near future revealed that increased milk production is seen as most relevant in relation to food safety. Other trends affecting food safety are climate change and changes at the farm level, which aim to improve animal welfare and environmental sustainability.

Assessing the sustainability of egg production systems in The Netherlands.

Housing systems for laying hens have changed over the years due to increased public concern regarding animal welfare. In terms of sustainability, animal welfare is just one aspect that needs to be considered. Social aspects as well as environmental and economic factors need to be included as well. In this study, we assessed the sustainability of enriched cage, barn, free-range, and organic egg production systems following a predefined protocol. Indicators were selected within the social, environmental, and economic dimensions, after which parameter values and sustainability limits were set for the core indicators in order to quantify sustainability. Uncertainty in the parameter values as well as assigned weights and compensabilities of the indicators influenced the outcome of the sustainability assessment. Using equal weights for the indicators showed that, for the Dutch situation, enriched cage egg production was most sustainable, having the highest score on the environmental dimension, whereas free-range egg production gave the highest score in the social dimension (covering food safety, animal welfare, and human welfare). In the economic dimension both enriched cage egg and organic egg production had the highest sustainability score. When weights were attributed according to stakeholder outputs, individual differences were seen, but the overall scores were comparable to the sustainability scores based on equal weights. The provided method enabled a quantification of sustainability using input from stakeholders to include societal preferences in the overall assessment. Allowing for different weights and compensabilities helps policymakers in communicating with stakeholders involved and provides a weighted decision regarding future housing systems for laying hens.

Transfer of perfluorooctane sulfonic acid (PFOS) from contaminated feed to dairy milk.

Dietary intake is the predominant route for human exposure to perfluorooctane sulfonic acid (PFOS). Single pollution events may thus affect human exposure if polluted ground and water is used to produce animal feed or food. In this study, a physiologically based pharmacokinetic (PBPK-) model is derived that describes the uptake of PFOS from contaminated feed by cows and its subsequent elimination through the cows' milk. Parameter values of the model were estimated by fitting to experimental data of a cow feeding trial. Model calculations showed that almost all PFOS ingested is excreted through the cows' milk. The elimination rate, however, was low as the estimated half-life in the cow was 56days and it may, thus, take a long time after an initial pollution event to produce PFOS-free milk. The derived model can be used to estimate the transfer of PFOS through the dairy food chain and can be used for comparison of various contamination routes.

Changes in time of sowing, flowering and maturity of cereals in Europe under climate change.

The phenological development of cereal crops from emergence through flowering to maturity is largely controlled by temperature, but also affected by day length and potential physiological stresses. Responses may vary between species and varieties. Climate change will affect the timing of cereal crop development, but exact changes will also depend on changes in varieties as affected by plant breeding and variety choices. This study aimed to assess changes in timing of major phenological stages of cereal crops in Northern and Central Europe under climate change. Records on dates of sowing, flowering, and maturity of wheat, oats and maize were collected from field experiments conducted during the period 1985-2009. Data for spring wheat and spring oats covered latitudes from 46 to 64°N, winter wheat from 46 to 61°N, and maize from 47 to 58°N. The number of observations (site-year-variety combinations) varied with phenological phase, but exceeded 2190, 227, 2076 and 1506 for winter wheat, spring wheat, spring oats and maize, respectively. The data were used to fit simple crop development models, assuming that the duration of the period until flowering depends on temperature and day length for wheat and oats, and on temperature for maize, and that the duration of the period from flowering to maturity in all species depends on temperature only. Species-specific base temperatures were used. Sowing date of spring cereals was estimated using a threshold temperature for the mean air temperature during 10 days prior to sowing. The mean estimated temperature thresholds for sowing were 6.1, 7.1 and 10.1°C for oats, wheat and maize, respectively. For spring oats and wheat the temperature threshold increased with latitude. The effective temperature sums required for both flowering and maturity increased with increasing mean annual temperature of the location, indicating that varieties are well adapted to given conditions. The responses of wheat and oats were largest for the period from flowering to maturity. Changes in timing of cereal phenology by 2040 were assessed for two climate model projections according to the observed dependencies on temperature and day length. The results showed advancements of sowing date of spring cereals by 1-3 weeks depending on climate model and region within Europe. The changes were largest in Northern Europe. Timing of flowering and maturity were projected to advance by 1-3 weeks. The changes were largest for grain maize and smallest for winter wheat, and they were generally largest in the western and northern part of the domain. There were considerable differences in predicted timing of sowing, flowering and maturity between the two climate model projections applied.

Farm and slaughterhouse characteristics affecting the occurrence of Salmonella and Campylobacter in the broiler supply chain.

Based on a data set on Campylobacter and Salmonella prevalence in the broiler supply chain, collected during the period 2002 through 2005 in the Netherlands, farm- and slaughterhouse-specific characteristics were tested for their effect on Campylobacter and Salmonella prevalence at different stages of the broiler supply chain. Three different sampling points were considered: departure from the farm, arrival at the slaughterhouse, and the end of the slaughterline. Strong associations were found between Salmonella and Campylobacter prevalence at a particular sampling point and their prevalence at the preceding point of the chain. Statistical analyses showed that the country of origin of the broiler farm had a significant effect on the prevalence of Salmonella and Campylobacter at slaughterhouse arrival. The feeding company delivering to the farm also showed a significant effect on the occurrence of both pathogens at departure from the broiler farm. The prevalence of Campylobacter decreased with an increasing number of birds per flock, whereas the prevalence of Salmonella increased with an increasing number of birds per flock. The number of flocks processed within a specific slaughterhouse was not associated with an increased or decreased prevalence of Campylobacter and Salmonella. The results provide more insight into factors related to the occurrence of both pathogens and in understanding their epidemiology. The results can be supportive in decision making on measures to reduce the contamination of broiler products with Salmonella and Campylobacter.

A Dutch field survey on fungal infection and mycotoxin concentrations in maize.

Mycotoxins are secondary metabolites produced by fungi that can cause adverse health effects. Due to climate change, temperatures are expected to rise and changes in rainfall patterns are foreseen. These developments may increase fungal occurrence and mycotoxin concentrations in maize. It is therefore useful to monitor mycotoxin levels in maize and record the accompanying agronomic factors and weather parameters. This paper describes a field survey in the Netherlands in which information on soil, cultivar, green manure, tillage as well as sowing, emergence, flowering and harvest dates of silage maize were collected from 148 growers. A small number of these growers (42 in total) were visited to collect maize samples revealing that 50% of the samples were contaminated with Fusarium species and mycotoxins were detected in 25% of the samples. The Fusarium species that was most commonly found was F. crookwellense followed by F. graminearum, F. culmorum, F. sporotrichiodes and F. equiseti. In total 31 mycotoxins were analysed. The predominant mycotoxins present were (sum of 3 and 15)-acetyl-DON and nivalenol; other mycotoxins found were alternariol, beauvericin, deoxynivalenol, diacetoxyscirpenol, moniliformin and zearalenone. Nivalenol was present in concentrations up to 1670 µg kg⁻¹ and acetylated DON was usually present at higher concentrations than DON. Statistical analysis of the current data showed no correlation between mycotoxins present and agronomic factors recorded. Field studies as described in this paper are useful and need to be continued in the future in order to observe trends in mycotoxin occurrence.

Mycotoxin contamination of cereal grain commodities in relation to climate in North West Europe.

This study aimed to investigate mycotoxin contamination of cereal grain commodities for feed and food production in North Western Europe during the last two decades, including trends over time and co-occurrence between toxins, and to assess possible effects of climate on the presence of mycotoxins. For these aims, analytical results related to mycotoxin contamination of cereal grain commodities, collected in the course of national monitoring programmes in Finland, Sweden, Norway and the Netherlands during a 20-year period, were gathered. Historical observational weather data, including daily relative humidity, rainfall and temperature, were obtained from each of these four countries. In total 6382 records, referring to individual sample results for mycotoxin concentrations (one or more toxins) in cereal grains were available. Most records referred to wheat, barley, maize and oats. The most frequently analysed mycotoxins were deoxynivalenol, 3-acetyl-deoxynivalenol, nivalenol, T-2 toxin, HT-2 toxin and zearalenone. Deoxynivalenol had the highest overall incidence of 46%, and was mainly found in wheat, maize and oats. Mycotoxins that showed co-occurrence were: deoxynivalenol and 3-acetyl-deoxynivalenol in oats; deoxynivalenol and zearalenone in maize and wheat; and T-2 toxin and HT-2 toxin in oats. The presence of both deoxynivalenol and zearalenone in wheat increased with higher temperatures, relative humidity and rainfall during cultivation, but the presence of nivalenol was negatively associated with most of these climatic factors. The same holds for both nivalenol and deoxynivalenol in oats. This implies that climatic conditions that are conducive for one toxin may have a decreasing effect on the other. The presence of HT-2 toxin in oats showed a slight decreasing trends over time, but significant trends for other toxins showed an increasing presence during the last two decades. It is therefore useful to continue monitoring of mycotoxins. Obtained results can be used for development of predictive models for presence of mycotoxins in cereal grains.

Modelling mycotoxin formation by Fusarium graminearum in maize in The Netherlands.

The predominant species in maize in temperate climates is Fusarium graminearum, which produces the mycotoxins deoxynivalenol and zearalenone. Projected climate change is expected to affect Fusarium incidence and thus the occurrence of these mycotoxins. Predictive models may be helpful in determining trends in the levels of these mycotoxins with expected changing climatic conditions. The aim of this study was to develop a model describing fungal infection and subsequent growth as well as the formation of deoxynivalenol and zearalenone in maize in The Netherlands. For this purpose, a published Italian model was used as a starting point. This model is a mixed empiric-mechanistic model that describes fungal infection during silking (based on wind speed and rainfall) and subsequent germination, growth and toxin formation (depending on temperature and water availability). Model input uses weather parameters and crop management factors, such as maize hybrid, sowing date, flowering period and harvest date. Model parameter values were obtained by fitting these parameters to deoxynivalenol and zearalenone measurements in Dutch maize, using national mycotoxin data from the years 2002-2007. The results showed that the adapted model is capable of describing the trend in average deoxynivalenol and zearalenone levels over these years. Validation with external data is needed to verify model outcomes. It is expected that the current model can be used to estimate the effect of projected climate change on trends in deoxynivalenol and zearalenone levels in the coming years.

Farm factors associated with the use of antibiotics in pig production.

The aim of this study was to investigate farm-level economic and technical factors that are associated with the use of antibiotics on pig farms. Identification of such factors, like farm size and net farm result, may help to increase epidemiological knowledge and to specify farm advice and policy making to reduce inappropriate use of antibiotics. The study used over 300 farm-year records collected during 2004 to 2007 from pig farms in the Netherlands. Data included economic and technical factors as well as antibiotic administration. Data were statistically analyzed for factors associated with antibiotic use, both for fattening pig and sow farms (piglets only), separately. The response variable was the average number of daily dosages per average pig year. Statistical analysis was performed on 16 and 19 potential explanatory factors for the fattening pig and sow farms, respectively. The results showed that, both on the fattening pig and sow farms, the average use of antibiotics increased from 2004 to 2006, but decreased during 2007, but the effect of year was not significant (P > 0.05). Use of antibiotics varied between individual farms. Large farm repeatability for the use of antibiotics in the different years was found. Factors associated (P < 0.05) with the use of antibiotics included: farm system, number of pigs, and population density in the region of the farm (for sow farms only). As these factors are easy to collect and to register, they can be used to specify farm advice and investigation, as well as for policy making. The majority of the technical and economic factors were not significantly (P > 0.05) related to the on-farm use of antibiotics. Therefore, it is recommended to focus future research on the potential role of socioeconomic factors associated with antibiotic use on pig farms.

Perfluorooctane sulphonate (PFOS) throughout the food production chain.

Perfluorooctane sulphonate (PFOS) is a persistent organic pollutant with adverse effects on human health. Since dietary intake plays an important role in human exposure, the transfer of PFOS throughout the food chain needs further investigation. The aim of this paper is to give an overview of PFOS concentrations and transfer for the various chain steps from farm-to-fork. This reveals that most research focused on levels of PFOS in surface water and fish but data on soil and crops are largely missing. Furthermore, the uptake of PFOS by farm animals and subsequent transfer into meat and animal products needs further attention, as these products will eventually be consumed by the human population. Once the necessary data gaps are filled, the contribution of the various chain steps on the total PFOS intake can be established. Moreover, the effect of pollution events on the food chain can be established enabling appropriate actions in order to protect consumer health.

Selection of critical factors for identifying emerging food safety risks in dynamic food production chains.

A pro-active emerging risk identification system starts with the selection of critical factors related to the occurrence of emerging hazards. This paper describes a method to derive the most important factors in dynamic production chains starting from a gross list of critical factors. The method comprised the semi-quantitative evaluation of the critical factors for a relatively novel product on the Dutch market and a related traditional product. This method was tested in an expert study with three case studies. The use of group discussion followed by individual ranking in an expert study proved to be a powerful tool in identifying the most important factors for each case. Human behaviour (either producers' behaviour or human knowledge) was the most important factor for all three cases. The expert study showed that further generalization of critical factors based on product characteristics may be possible.

Salmonella serotype distribution in the Dutch broiler supply chain.

Salmonella serotype distribution can give insight in contamination routes and persistence along a production chain. Therefore, it is important to determine not only Salmonella prevalence but also to specify the serotypes involved at the different stages of the supply chain. For this purpose, data from a national monitoring program in the Netherlands were used to estimate the serotype distribution and to determine whether this distribution differs for the available sampling points in the broiler supply chain. Data covered the period from 2002 to 2005, all slaughterhouses (n = 22), and the following 6 sampling points: departure from hatchery, arrival at the farm, departure from the farm, arrival at the slaughterhouse, departure from the slaughterhouse, and end of processing. Furthermore, retail data for 2005 were used for comparison with slaughterhouse data. The following serotypes were followed throughout the chain: Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Paratyphi B var. Java (Salmonella Java), Salmonella Infantis, Salmonella Virchow, and Salmonella Mbandaka. Results showed that serotype distribution varied significantly throughout the supply chain (P < 0.05). Main differences were found at the farm and at the slaughterhouse (within one stage), and least differences were found between departure from one stage and arrival at the next stage. The most prominent result was the increase of Salmonella Java at farm level. This serotype remained the most prominent pathogen throughout the broiler supply chain up to the retail phase.

Prevalence of Salmonella in the broiler supply chain in The Netherlands.

This article presents detailed information on Salmonella prevalence throughout the broiler supply chain in The Netherlands, based on results from a national monitoring program. Data were collected during the period 2002 through 2005 and from six sampling points in the chain, covering hatchery up to and including processing. Trends in Salmonella prevalence over years and seasons were analyzed as well as the effect of slaughterhouse capacity on these trends. In addition, correlations between the occurrence of Salmonella at the various sampling points were calculated. The results showed a decreasing trend of Salmonella prevalence from 2002 through 2005 at all sampling points. A seasonal effect on the occurrence of Salmonella was found at the broiler farm, with a higher prevalence during the third and fourth quarter of the year (July through December). The higher the capacity of the slaughterhouse, the lower Salmonella prevalence on arrival at the slaughterhouse and the higher the prevalence at the end of slaughter and the end of processing. The detailed insights obtained in this study could be used to focus future field and experimental research on the prevention and control of Salmonella in the broiler supply chain. Results presented could also be used in risk assessment studies.