Investigation of ochratoxin A in air-dry-cured hams

The European Union legislation regarding ochratoxin A (OTA) in various foodstuffs has changed relatively recently. Nevertheless, the legislation does not regulate OTA in any meat and meat-derived products. In this legislation update, the European Commission requested new studies, including, besides others, the presence of OTA in hams, which raises the concern that its consumption may pose a potential risk of exposure to OTA. This study aims to investigate OTA in a total of 195 samples of air-dry-cured hams acquired at the Czech market from January to June 2023. The analytical technique of high-performance liquid chromatography in combination with a fluorescence detector with pre-treatment employing immunoaffinity columns was used to determine OTA. OTA was found in 93 (48%) samples of air-dry-cured ham, with the OTA concentration reaching up to 14.58 ng/g. Due to the current absence of regulation limits, the results of this study were compared with the Italian maximum limit of 1 ng/g regulating OTA in porcine meat and byproducts. The Italian OTA maximum limit was exceeded in 22 (11%) samples. This study shows that the population of the Czech Republic is exposed to OTA from this pork byproduct. It is essential to set an OTA regulatory limit for meat and food produced from it to protect human health.

Efficacy of a multicomponent binding agent against combined exposure to zearalenone and ochratoxin A in weaned pigs

Introduction

The study aimed to evaluate the efficacy of a novel multicomponent substance against combined exposure to the mycotoxins zearalenone (ZEN) and ochratoxin A (OTA) in weaned piglets.

Methods

In total, 60 piglets at the age of 28 days were equally allocated to four experimental groups (A-D), consisting of eight female and seven male piglets each (15 animals per group, for a total trial duration of 42 days). Animals from group A received typical weaner feed without mycotoxins or the test product [multicomponent mycotoxin detoxifying agent (MMDA)]. Group B animals received the same weaner feed contaminated with 0.992 mg ZEN/kg feed and 0.531 mg OTA/kg feed without the addition of the MMDA. Animals in group C received the same contaminated feed as group B with the addition of 1.5 g MMDA/kg feed, whereas group D received the same feed as group B with the inclusion of 3 g MMDA/kg feed. Clinical signs and performance parameters [body weight (BW), average daily weight gain (ADWG), and feed conversion ratio (FCR)] were evaluated, while mycotoxin residues were also assessed in the liver and kidney tissues.

Results

Findings showed improved FCR in the group that received the greatest dose of the test product (3 g MMDA/kg feed) compared to the group that received the lower dose (1.5 g MMDA/kg feed). A few hematological and biochemical parameters were slightly altered, predominantly within normal limits. The residue analysis demonstrated a reduction of OTA in liver samples, a-ZEL in the liver and total tested samples, and a total of ZEN and metabolite contents in all samples of the group that received the greatest MMDA dose in comparison to the group that received the toxins without the addition of the test product.

Discussion

Therefore, a positive effect of the MMDA at the greatest dosage regime on reducing bioavailability and tissue deposition of ZEN and OTA, with a particularly positive effect on FCR in weaned pigs, is suggested under concurrent ZEN and OTA exposure in vivo.

Risks for animal health related to the presence of ochratoxin A (OTA) in feed

In 2004, the EFSA Panel on Contaminants in the Food Chain (CONTAM) adopted a Scientific Opinion on the risks to animal health and transfer from feed to food of animal origin related to the presence of ochratoxin A (OTA) in feed. The European Commission requested EFSA to assess newly available scientific information and to update the 2004 Scientific Opinion. OTA is produced by several fungi of the genera Aspergillus and Penicillium. In most animal species it is rapidly and extensively absorbed in the gastro-intestinal tract, binds strongly to plasma albumins and is mainly detoxified to ochratoxin alpha (OTalpha) by ruminal microbiota. In pigs, OTA has been found mainly in liver and kidney. Transfer of OTA from feed to milk in ruminants and donkeys as well as to eggs from poultry is confirmed but low. Overall, OTA impairs function and structure of kidneys and liver, causes immunosuppression and affects the zootechnical performance (e.g. body weight gain, feed/gain ratio, etc.), with monogastric species being more susceptible than ruminants because of limited detoxification to OTalpha. The CONTAM Panel considered as reference point (RP) for adverse animal health effects: for pigs and rabbits 0.01 mg OTA/kg feed, for chickens for fattening and hens 0.03 mg OTA/kg feed. A total of 9,184 analytical results on OTA in feed, expressed in dry matter, were available. Dietary exposure was assessed using different scenarios based on either model diets or compound feed (complete feed or complementary feed plus forage). Risk characterisation was made for the animals for which an RP could be identified. The CONTAM Panel considers that the risk related to OTA in feed for adverse health effects for pigs, chickens for fattening, hens and rabbits is low.

Enzymatic degradation of ochratoxin A in the gastrointestinal tract of piglets

Animal feeds are often contaminated with ochratoxin A (OTA), a potent natural mycotoxin hazardous to animal and human health that accumulates in blood and tissues. To the best of our knowledge, this study is the first to investigate the in vivo application of an enzyme (OTA amidohydrolase; OAH) that degrades OTA into the nontoxic molecules phenylalanine and ochratoxin α (OTα) in the gastrointestinal tract (GIT) of pigs. Piglets were fed six experimental diets over 14 days, varying in OTA contamination level (50 or 500 μg/kg; OTA50 and OTA500) and presence of OAH; a negative control diet (no OTA added) and a diet containing OTα at 318 µg/kg (OTα318). The absorption of OTA and OTα into the systemic circulation (plasma and dried blood spots, DBS), their accumulation in kidney, liver, and muscle tissues, and excretion through feces and urine were assessed. The efficiency of OTA degradation in the digesta content of the GIT was also estimated. At the end of the trial, accumulation of OTA in blood was significantly higher in OTA groups (OTA50 and OTA500) in comparison to enzyme groups (OAH50 and OAH500, respectively). The supplementation of OAH explicitly reduced the absorption of OTA (P < 0.005) into plasma by 54% and 59% (from 40.53 ± 3.53 to 18.66 ± 2.28 ng/mL in piglets fed the 50 μg OTA/kg diets and from 413.50 ± 71.88 to 168.35 ± 41.02 ng/mL in piglets fed the 500 μg OTA/kg diets, respectively) and in DBS by 50% and 53% (from 22.79 ± 2.63 to 10.67 ± 1.93 ng/mL in piglets fed the 50 μg OTA/kg diets and from 232.85 ± 35.16 to 105.71 ± 24.18 ng/mL in piglets fed the 500 μg OTA/kg diets, respectively). The OTA concentrations in plasma were positively associated with the OTA levels detected in all tissues analyzed; adding OAH reduced OTA levels in the kidney, liver, and muscle (P < 0.005) by 52%, 67%, and 59%, respectively. The analysis of GIT digesta content showed that OAH supplementation led to OTA degradation in the proximal GIT where natural hydrolysis is inefficient. Overall, the data of present in vivo study demonstrated that supplementation of swine feeds with OAH successfully reduced OTA levels in blood (plasma and DBS) as well as in kidney, liver, and muscle tissues. Therefore, an approach to use enzymes as feed additives might be most promising to mitigate the harmful effects of OTA on the productivity and welfare of pigs and at the same time improving the safety of pig-derived food products.

Investigation of ochratoxin a in blood sausages in the Czech Republic: Comparison with data over Europe

Blood sausages consisting of groats, pork, porcine offal, fat, blood, and spices are very popular in the Czech Republic. All these ingredients are potential sources of dietary exposure to ochratoxin A (OTA). OTA has a strong affinity to serum proteins in porcine blood. Thus, the contamination of blood sausages with OTA can be expected. This study aims to evaluate OTA in 200 samples of porcine blood sausages purchased at the Czech market during 2020-2021. The analytical method high-performance liquid chromatography coupled with fluorescence detection with pre-treatment using immunoaffinity columns was employed to determine OTA. The limit of detection was 0.03 ng/g and the limit of quantification 0.10 ng/g. Recovery was 71.6 %. All samples were positive at contents ranging from 0.15 to 5.68 ng/g with a mean of 1.47 ng/g, and a median of 1.26 ng/g. A total of 66% of these samples contained OTA content exceeding the maximum limit of 1 ng/g set in Italy. This study demonstrates that the Czech population is exposed to OTA from blood sausages. The proposed preliminary action limit for OTA in blood sausages should be set at 1 ng/g. No regulatory limits for OTA in blood sausages have been established yet in the European Union legislation. To protect human health, further monitoring of OTA in these products is necessary.

Ochratoxin A in Slaughtered Pigs and Pork Products

Ochratoxin A (OTA) is a mycotoxin that is produced after the growth of several Aspergillus and Penicillium spp. in feeds or foods. OTA has been proved to possess nephrotoxic, hepatotoxic, teratogenic, neurotoxic, genotoxic, carcinogenic and immunotoxic effects in animals and humans. OTA has been classified as possibly carcinogenic to humans (Group 2B) by the IARC in 2016. OTA can be mainly found in animals as a result of indirect transmission from naturally contaminated feed. OTA found in feed can also contaminate pigs and produced pork products. Additionally, the presence of OTA in pork meat products could be derived from the direct growth of OTA-producing fungi or the addition of contaminated materials such as contaminated spices. Studies accomplished in various countries have revealed that pork meat and pork meat products are important sources of chronic dietary exposure to OTA in humans. Various levels of OTA have been found in pork meat from slaughtered pigs in many countries, while OTA levels were particularly high in the blood serum and kidneys of pigs. Pork products made from pig blood or organs such as the kidney or liver have been often found to becontaminated with OTA. The European Union (EU) has established maximum levels (ML) for OTA in a variety of foods since 2006, but not for meat or pork products. However, the establishement of an ML for OTA in pork meat and meat by-products is necessary to protect human health.

A survey on occurrence of ochratoxin A in the kidneys of slaughtered pigs in the Czech Republic during the years 2012–2021

Ochratoxin A (OTA) is a mycotoxin produced by several moulds of Aspergillus and Penicillium genera on many agricultural commodities used for feed production. It is primarily a nephrotoxic substance, but it can also cause immunosuppression in pigs and increase their susceptibility to infections. Porcine mycotoxic nephropathy (PMN) is a chronic poisoning associated with OTA exposure. The aim of this paper was to evaluate the content of OTA in pig kidneys which were examined during the regular monitoring of the safety and quality of food of animal origin in the Czech Republic during the years 2012–2021. Results revealed no differences between the monitored years or age categories and no differences between the year seasons, which could have an influence on the storage conditions and thus feed contamination by moulds. The values found in this study are low and similar to those assessed in several studies performed in other European countries and do not exceed the limits set in their legislation, which means these organs do not pose a risk for consumers and do not indicate PMN in monitored pigs. Czech Republic as well as EU legislation do not regulate OTA levels in the food of animal origin yet.

The Occurrence and Contamination Level of Ochratoxin A in Plant and Animal-Derived Food Commodities

Ochratoxin A (OTA) is a highly toxic mycotoxin and poses great threat to human health. Due to its serious toxicity and widespread contamination, great efforts have been made to evaluate its human exposure. This review focuses on the OTA occurrence and contamination level in nine plant and animal derived food commodities: cereal, wine, coffee, beer, cocoa, dried fruit, spice, meat, and milk. The occurrence and contamination level varied greatly in food commodities and were affected by many factors, including spices, geography, climate, and storage conditions. Therefore, risk monitoring must be routinely implemented to ensure minimal OTA intake and food safety.

Mycotoxin Biomarkers in Pigs-Current State of Knowledge and Analytics

Farm animals are frequently exposed to mycotoxins, which have many adverse effects on their health and become a significant food safety issue. Pigs are highly exposed and particularly susceptible to mycotoxins, which can cause many adverse effects. For the above reasons, an appropriate diagnostic tool is needed to monitor pig' exposure to mycotoxins. The most popular tool is feed analysis, which has some disadvantages, e.g., it does not include individual exposure. In recent years, the determination of biomarkers as a method to assess the exposure to mycotoxins by using concentrations of the parent compounds and/or metabolites in biological matrices is becoming more and more popular. This review provides a comprehensive overview of reported in vivo mycotoxin absorption, distribution, metabolism and excretion (ADME) and toxicokinetic studies on pigs. Biomarkers of exposure for aflatoxins, deoxynivalenol, ochratoxin A, fumonisins, T-2 toxin and zearalenone are described to select the most promising compound for analysis of porcine plasma, urine and faeces. Biomarkers occur in biological matrices at trace levels, so a very sensitive technique-tandem mass spectrometry-is commonly used for multiple biomarkers quantification. However, the sample preparation for multi-mycotoxin methods remains a challenge. Therefore, a summary of different biological samples preparation strategies is included in that paper.

Occurrence of Ochratoxin A in Different Types of Cheese Offered for Sale in Italy

The detection of Ochratoxin A (OTA) in the milk of ruminants occurs infrequently and at low levels, but its occurrence may be higher in dairy products such as cheese. The aim of this study was to investigate the presence of OTA in cheeses purchased in the metropolitan city of Bologna (Italy) and the surrounding area. For the analysis, a LC-MS/MS method with a limit of quantification (LOQ) of 1 µg/kg was used. OTA was detected in seven out of 51 samples of grated hard cheese (concentration range 1.3-22.4 µg/kg), while it was not found in the 33 cheeses of other types which were also analysed. These data show a low risk of OTA contamination for almost all types of cheese analysed. To improve the safety of cheese marketed in grated form, more regulations on cheese rind, which is the part most susceptible to OTA-producing moulds, should be implemented or, alternatively, producers should consider not using the rind as row material for grated cheese. It would be interesting to continue these investigations particularly on grated hard cheeses to have more data to update the risk assessment of OTA in cheese, as also suggested by EFSA in its 2020 scientific opinion on OTA.

Ochratoxin A contamination of the casing and the edible portion of artisan salamis produced in two Italian regions

The purpose of this study was to provide data on the presence of ochratoxin A (OTA) in artisan salamis produced in the Campania and Marche regions (Italy). For this aim, 96 different salamis were purchased from farms and small salami factories. Analysis were carried out firstly on the casings of all samples, and in a second step, in the outer and inner edible parts of those samples whose casings were found positive for OTA at concentration levels above the Italian guideline value established for OTA in pork meat (1 μg/kg). The analytical method, based on a sample preparation procedure with immunoaffinity columns, together with analysis by LC-MS/MS, has guaranteed average recoveries between 79.4 and 89.0%, limits of detection (LOD) and quantification (LOQ) of 0.10 and 0.25 μg/kg, respectively. OTA was detected in 25.0% of the analysed casings (24 samples) at concentration ranging from 0.25 to 98.52 μg/kg. Ten of these samples were from the same production plant in which an additional sampling was carried out, and where a problem of environmental contamination by ochratoxigenic moulds probably exists. The edible parts were mostly uncontaminated, except in 3 samples, 2 of which showed OTA contamination levels above 1 μg/kg. The presence of OTA on the casing does not seem to be cause for alarm about the safety of this type of product but it should in any case be monitored. Before slicing the meat for consumption, it is always good practice to peel the casing even if reported as edible on salami label.

Risk assessment of ochratoxin A in food

The European Commission asked EFSA to update their 2006 opinion on ochratoxin A (OTA) in food. OTA is produced by fungi of the genus Aspergillus and Penicillium and found as a contaminant in various foods. OTA causes kidney toxicity in different animal species and kidney tumours in rodents. OTA is genotoxic both in vitro and in vivo; however, the mechanisms of genotoxicity are unclear. Direct and indirect genotoxic and non-genotoxic modes of action might each contribute to tumour formation. Since recent studies have raised uncertainty regarding the mode of action for kidney carcinogenicity, it is inappropriate to establish a health-based guidance value (HBGV) and a margin of exposure (MOE) approach was applied. For the characterisation of non-neoplastic effects, a BMDL 10 of 4.73 μg/kg body weight (bw) per day was calculated from kidney lesions observed in pigs. For characterisation of neoplastic effects, a BMDL 10 of 14.5 μg/kg bw per day was calculated from kidney tumours seen in rats. The estimation of chronic dietary exposure resulted in mean and 95th percentile levels ranging from 0.6 to 17.8 and from 2.4 to 51.7 ng/kg bw per day, respectively. Median OTA exposures in breastfed infants ranged from 1.7 to 2.6 ng/kg bw per day, 95th percentile exposures from 5.6 to 8.5 ng/kg bw per day in average/high breast milk consuming infants, respectively. Comparison of exposures with the BMDL 10 based on the non-neoplastic endpoint resulted in MOEs of more than 200 in most consumer groups, indicating a low health concern with the exception of MOEs for high consumers in the younger age groups, indicating a possible health concern. When compared with the BMDL 10 based on the neoplastic endpoint, MOEs were lower than 10,000 for almost all exposure scenarios, including breastfed infants. This would indicate a possible health concern if genotoxicity is direct. Uncertainty in this assessment is high and risk may be overestimated.

Assessment of Ochratoxin A Exposure in Ornamental and Self-Consumption Backyard Chickens

Ochratoxin A (OTA) is a mycotoxin that may be present in various food and feed of plant and animal origin, including chicken meat. In Italy, backyard poultry farming is rather widespread. Animals are raised for meat, eggs and for ornamental purpose, and they are often fed with home-made diets not subject to official controls. The purpose of this study was to evaluate exposure of ornamental and backyard chickens to OTA using biliary ochratoxin A as a biomarker. Therefore, bile samples, in addition to kidney, liver and muscle, were collected from 102 chickens reared in 16 farms located in 6 Italian regions. High-performance liquid chromatography method and fluorimetric detection (HPLC-FLD) analysis were carried out firstly on bile from all animals, and OTA was detected in 12 chickens (concentration range 3.83-170.42 µg/L). Subsequently, the kidneys of these chickens were also analysed, and the mycotoxin was not detected. The analytical detection limits (LODs) of OTA in bile and kidney were 2.1 µg/L and 0.1 µg/kg, respectively. In conclusion, these animals were exposed to OTA but their meat can be considered safe, given that this mycotoxin, if present, concentrates highest in kidneys. Biliary ochratoxin A confirms its use as a valid biomarker to assess exposure of poultry to OTA.

Protective effect of curcumin on ochratoxin A-induced liver oxidative injury in duck is mediated by modulating lipid metabolism and the intestinal microbiota

Curcumin has antioxidant functions, regulates the intestinal microbial composition, and alleviates mycotoxin toxicity. The present study aimed to explore whether curcumin could alleviate ochratoxin A (OTA)-induced liver injury via the intestinal microbiota. A total of 720 mixed-sex 1-day-old White Pekin ducklings were randomly assigned into 4 groups: CON (control group, without OTA), OTA (fed a diet with 2 mg/kg OTA), CUR (ducks fed a diet with 400 mg/kg curcumin), and OTA + CUR (2 mg/kg OTA plus 400 mg/kg curcumin). Each treatment consisted of 6 replicates and 30 ducklings per replicate. Treatment lasted for 21 D. Results were analyzed by a two-tailed Student t test between 2 groups. Our results demonstrated that OTA treatment had the highest serum low-density lipoprotein (LDL) level among 4 groups. Compared with OTA group, OTA + CUR decreased serum LDL level (P < 0.05). OTA decreased liver catalase (CAT) activity in ducks (P < 0.05), while addition of curcumin in OTA group increased liver CAT activity (P < 0.05). 16S ribosomal RNA sequencing suggested that curcumin increased the richness indices (ACE index) and diversity indices (Simpson index) compared with OTA group (P < 0.05) and recovered the OTA-induced alterations in composition of the intestinal microbiota. Curcumin supplementation relieved the decreased abundance of butyric acid producing bacteria, including blautia, butyricicoccus, and butyricimonas, induced by OTA (P < 0.05). OTA also significantly influenced the metabolism of the intestinal microbiota, such as tryptophan metabolism and glyceropholipid metabolism. Curcumin could alleviate the upregulation of oxidative stress pathways induced by OTA. OTA treatment also increased SREBP-1c expression (P < 0.05). The curcumin group had the lowest expression of FAS and PPARG mRNA (P < 0.05) and the highest expression of NRF2 and HMOX1 mRNA. These results indicated that curcumin could alleviate OTA-induced oxidative injury and lipid metabolism disruption by modulating the cecum microbiota.

Occurrence of ochratoxin A in typical salami produced in different regions of Italy

A total of 172 different salamis were purchased from farms and small salami factories located in four Italian regions (Piedmont, Veneto, Calabria, and Sicily) and analyzed for the presence of ochratoxin A (OTA). Analysis was performed by high-performance liquid chromatography coupled to a fluorimetric detector (HPLC-FLD). The detection limit (LOD) for the method used was 0.05 μg/kg, while the quantitation limit (LOQ) was 0.20 μg/kg; the average recovery rate was 89.1%. OTA was detected in 22 salamis, and 3 samples exceeded the Italian guidance value for OTA in pork meat (1 μg/kg). In particular, what emerges from this research is the high percentage of spicy salamis among positive samples (68.2%, 15 out of 22), although spicy salamis are only 27.3% of the total number of samples collected and analyzed. Red chili pepper contaminated by OTA could be responsible for the presence of the mycotoxin in these spicy salamis. It follow that, also the control of some ingredients used in the manufacture of these meat products, like spices, should not be neglected.

Ochratoxin A determination in swine muscle and liver from French conventional or organic farming production systems

Consumers generally considered organic products to be healthier and safer but data regarding the contamination of organic products are scarce. This study evaluated the impact of the farming system on the levels of ochratoxin A (OTA) in the tissues of French pigs (muscle and liver) reared following three different types of production (organic, Label Rouge and conventional). Because OTA is present at trace levels in animal products, a sensitive ultra-high performance liquid chromatography-tandem mass spectrometry method using stable isotope dilution assay was developed and validated. OTA was detected or quantified (LOQ of 0.10 μg kg^-1) in 67% (n = 47) of the 70 pig liver samples analysed, with concentrations ranging from <0.10 to 3.65 μg kg^-1. The maximum concentration was found in a sample from organic production but there were no significant differences in the content of OTA between farming systems. OTA was above the LOQ in four out of 25 samples of the pork muscles. A good agreement was found between OTA levels in muscle and liver (liver concentration = 2.9 × OTA muscle concentration, r = 0.981).