Acute phase response following pulmonary exposure to soluble and insoluble metal oxide nanomaterials in mice.

BACKGROUND: Acute phase response (APR) is characterized by a change in concentration of different proteins, including C-reactive protein and serum amyloid A (SAA) that can be linked to both exposure to metal oxide nanomaterials and risk of cardiovascular diseases. In this study, we intratracheally exposed mice to ZnO, CuO, Al2O3, SnO2 and TiO2 and carbon black (Printex 90) nanomaterials with a wide range in phagolysosomal solubility. We subsequently assessed neutrophil numbers, protein and lactate dehydrogenase activity in bronchoalveolar lavage fluid, Saa3 and Saa1 mRNA levels in lung and liver tissue, respectively, and SAA3 and SAA1/2 in plasma. Endpoints were analyzed 1 and 28 days after exposure, including histopathology of lung and liver tissues. RESULTS: All nanomaterials induced pulmonary inflammation after 1 day, and exposure to ZnO, CuO, SnO2, TiO2 and Printex 90 increased Saa3 mRNA levels in lungs and Saa1 mRNA levels in liver. Additionally, CuO, SnO2, TiO2 and Printex 90 increased plasma levels of SAA3 and SAA1/2. Acute phase response was predicted by deposited surface area for insoluble metal oxides, 1 and 28 days post-exposure. CONCLUSION: Soluble and insoluble metal oxides induced dose-dependent APR with different time dependency. Neutrophil influx, Saa3 mRNA levels in lung tissue and plasma SAA3 levels correlated across all studied nanomaterials, suggesting that these endpoints can be used as biomarkers of acute phase response and cardiovascular disease risk following exposure to soluble and insoluble particles.

Subacute oral toxicity investigation of selenium nanoparticles and selenite in rats.

Selenium (Se) nanoparticles have been proposed as food supplements. However, the particle formulation may exert unexpected toxicity. The aim was therefore to compare toxicity of low doses of Se nanoparticles and the dissolved, ionized Se species selenite. Female rats were dosed orally for 28 d with either: 0.05, 0.5, or 4 mg Se/kg body weight (bw)/day as 20 nm Se nanoparticles or 0.05 or 0.5 mg Se/kg bw/day as sodium selenite. Male rats were dosed 4 mg Se/kg bw/day as Se nanoparticles. Body weight and clinical appearance were recorded throughout the experiment. At necropsy, blood samples were taken for hematological and clinical chemistry analyses; organ weights were recorded. At the high-dose of Se nanoparticles, overt toxicity occurred and the female animals had to be euthanized prematurely, whereas the male animals were reduced in dose. At all doses of Se nanoparticles and at 0.5 mg Se/kg bw/day as selenite, a lower body weight gain as compared to vehicle occurred. Relative liver weight was increased for both Se formulations at 0.5 mg Se/kg bw/day. Creatinine clearance and urinary pH were affected in some Se dosed groups. There were no effects among dosed groups on brain neurotransmitters or on hematological parameters compared with controls. There were no histological changes in the livers of animals exposed to Se nanoparticles or to selenite. Based on effects on body weight and liver weight, selenium nanoparticles and ionic Se exerted similar toxicity. This suggests that a nanoparticle-specific toxicity of Se did not occur.

Primary genotoxicity in the liver following pulmonary exposure to carbon black nanoparticles in mice.

BACKGROUND: Little is known about the mechanism underlying the genotoxicity observed in the liver following pulmonary exposure to carbon black (CB) nanoparticles (NPs). The genotoxicity could be caused by the presence of translocated particles or by circulating inflammatory mediators released during pulmonary inflammation and acute-phase response. To address this, we evaluated induction of pulmonary inflammation, pulmonary and hepatic acute-phase response and genotoxicity following exposure to titanium dioxide (TiO2), cerium oxide (CeO2) or CB NPs. Female C57BL/6 mice were exposed by intratracheal instillation, intravenous injection or oral gavage to a single dose of 162 µg NPs/mouse and terminated 1, 28 or 180 days post-exposure alongside vehicle control. RESULTS: Liver DNA damage assessed by the Comet Assay was observed after intravenous injection and intratracheal instillation of CB NPs but not after exposure to TiO2 or CeO2. Intratracheal exposure to NPs resulted in pulmonary inflammation in terms of increased neutrophils influx for all NPs 1 and 28 days post-exposure. Persistent pulmonary acute phase response was detected for all NPs at all three time points while only a transient induction of hepatic acute phase response was observed. All 3 materials were detected in the liver by enhanced darkfield microscopy up to 180 days post-exposure. In contrast to TiO2 and CeO2 NPs, CB NPs generated ROS in an acellular assay. CONCLUSIONS: Our results suggest that the observed hepatic DNA damage following intravenous and intratracheal dosing with CB NPs was caused by the presence of translocated, ROS-generating, particles detected in the liver rather than by the secondary effects of pulmonary inflammation or hepatic acute phase response.

Effect of a long-term high-protein diet on survival, obesity development, and gut microbiota in mice.

Female C57BL/6J mice were fed a regular low-fat diet or high-fat diets combined with either high or low protein-to-sucrose ratios during their entire lifespan to examine the long-term effects on obesity development, gut microbiota, and survival. Intake of a high-fat diet with a low protein/sucrose ratio precipitated obesity and reduced survival relative to mice fed a low-fat diet. By contrast, intake of a high-fat diet with a high protein/sucrose ratio attenuated lifelong weight gain and adipose tissue expansion, and survival was not significantly altered relative to low-fat-fed mice. Our findings support the notion that reduced survival in response to high-fat/high-sucrose feeding is linked to obesity development. Digital gene expression analyses, further validated by qPCR, demonstrated that the protein/sucrose ratio modulated global gene expression over time in liver and adipose tissue, affecting pathways related to metabolism and inflammation. Analysis of fecal bacterial DNA using the Mouse Intestinal Tract Chip revealed significant changes in the composition of the gut microbiota in relation to host age and dietary fat content, but not the protein/sucrose ratio. Accordingly, dietary fat rather than the protein/sucrose ratio or adiposity is a major driver shaping the gut microbiota, whereas the effect of a high-fat diet on survival is dependent on the protein/sucrose ratio.

Epoxy composite dusts with and without carbon nanotubes cause similar pulmonary responses, but differences in liver histology in mice following pulmonary deposition.

BACKGROUND: The toxicity of dusts from mechanical abrasion of multi-walled carbon nanotube (CNT) epoxy nanocomposites is unknown. We compared the toxic effects of dusts generated by sanding of epoxy composites with and without CNT. The used CNT type was included for comparison. METHODS: Mice received a single intratracheal instillation of 18, 54 and 162 µg of CNT or 54, 162 and 486 µg of the sanding dust from epoxy composite with and without CNT. DNA damage in lung and liver, lung inflammation and liver histology were evaluated 1, 3 and 28 days after intratracheal instillation. Furthermore, the mRNA expression of interleukin 6 and heme oxygenase 1 was measured in the lungs and serum amyloid A1 in the liver. Printex 90 carbon black was included as a reference particle. RESULTS: Pulmonary exposure to CNT and all dusts obtained by sanding epoxy composite boards resulted in recruitment of inflammatory cells into lung lumen: On day 1 after instillation these cells were primarily neutrophils but on day 3, eosinophils contributed significantly to the cell population. There were still increased numbers of neutrophils 28 days after intratracheal instillation of the highest dose of the epoxy dusts. Both CNT and epoxy dusts induced DNA damage in lung tissue up to 3 days after intratracheal instillation but not in liver tissue. There was no additive effect of adding CNT to epoxy resins for any of the pulmonary endpoints. In livers of mice instilled with CNT and epoxy dust with CNTs inflammatory and necrotic histological changes were observed, however, not in mice instilled with epoxy dust without CNT. CONCLUSIONS: Pulmonary deposition of epoxy dusts with and without CNT induced inflammation and DNA damage in lung tissue. There was no additive effect of adding CNT to epoxies for any of the pulmonary endpoints. However, hepatic inflammatory and necrotic histopathological changes were seen in mice instilled with sanding dust from CNT-containing epoxy but not in mice instilled with reference epoxy.

Changes in cholesterol homeostasis and acute phase response link pulmonary exposure to multi-walled carbon nanotubes to risk of cardiovascular disease.

Adverse lung effects following pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) are well documented in rodents. However, systemic effects are less understood. Epidemiological studies have shown increased cardiovascular disease risk after pulmonary exposure to airborne particles, which has led to concerns that inhalation exposure to MWCNTs might pose similar risks. We analyzed parameters related to cardiovascular disease, including plasma acute phase response (APR) proteins and plasma lipids, in female C57BL/6 mice exposed to a single intratracheal instillation of 0, 18, 54 or 162µg/mouse of small, entangled (CNTSmall, 0.8±0.1µm long) or large, thick MWCNTs (CNTLarge, 4±0.4µm long). Liver tissues and plasma were harvested 1, 3 and 28days post-exposure. In addition, global hepatic gene expression, hepatic cholesterol content and liver histology were used to assess hepatic effects. The two MWCNTs induced similar systemic responses despite their different physicochemical properties. APR proteins SAA3 and haptoglobin, plasma total cholesterol and low-density/very low-density lipoprotein were significantly increased following exposure to either MWCNTs. Plasma SAA3 levels correlated strongly with pulmonary Saa3 levels. Analysis of global gene expression revealed perturbation of the same biological processes and pathways in liver, including the HMG-CoA reductase pathway. Both MWCNTs induced similar histological hepatic changes, with a tendency towards greater response following CNTLarge exposure. Overall, we show that pulmonary exposure to two different MWCNTs induces similar systemic and hepatic responses, including changes in plasma APR, lipid composition, hepatic gene expression and liver morphology. The results link pulmonary exposure to MWCNTs with risk of cardiovascular disease.

MWCNTs of different physicochemical properties cause similar inflammatory responses, but differences in transcriptional and histological markers of fibrosis in mouse lungs.

Multi-walled carbon nanotubes (MWCNTs) are an inhomogeneous group of nanomaterials that vary in lengths, shapes and types of metal contamination, which makes hazard evaluation difficult. Here we present a toxicogenomic analysis of female C57BL/6 mouse lungs following a single intratracheal instillation of 0, 18, 54 or 162 µg/mouse of a small, curled (CNT(Small), 0.8 ± 0.1 µm in length) or large, thick MWCNT (CNT(Large), 4 ± 0.4 µm in length). The two MWCNTs were extensively characterized by SEM and TEM imaging, thermogravimetric analysis, and Brunauer-Emmett-Teller surface area analysis. Lung tissues were harvested 24h, 3 days and 28 days post-exposure. DNA microarrays were used to analyze gene expression, in parallel with analysis of bronchoalveolar lavage fluid, lung histology, DNA damage (comet assay) and the presence of reactive oxygen species (dichlorodihydrofluorescein assay), to profile and characterize related pulmonary endpoints. Overall changes in global transcription following exposure to CNT(Small) or CNT(Large) were similar. Both MWCNTs elicited strong acute phase and inflammatory responses that peaked at day 3, persisted up to 28 days, and were characterized by increased cellular influx in bronchoalveolar lavage fluid, interstitial pneumonia and gene expression changes. However, CNT(Large) elicited an earlier onset of inflammation and DNA damage, and induced more fibrosis and a unique fibrotic gene expression signature at day 28, compared to CNT(Small). The results indicate that the extent of change at the molecular level during early response phases following an acute exposure is greater in mice exposed to CNT(Large), which may eventually lead to the different responses observed at day 28.

Levels and risk assessment of chemical contaminants in byproducts for animal feed in Denmark.

With aim to provide information on chemical contaminants in byproducts in animal feed, the data from an official control by the Danish Plant Directorate during 1998-2009, were reviewed and several samples of citrus pulp and dried distillers grains with solubles (DDGS) were additionally collected for analysis and risk assessment. The levels of contaminants in the samples from the official control were below maximum limits from EU regulations with only a few exceptions in the following groups; dioxins and dioxin-like polychlorobiphenyls (PCBs) in fish-containing byproducts and dioxins in vegetable and animal fat, hydrogen cyanide in linseed, and cadmium in sunflowers. The levels of pesticides and mycotoxins in the additionally collected samples were below maximum limits. Enniatin B (ENN B) was present in all DDGS samples. The hypothetical cases of carry-over of contamination from these byproducts were designed assuming total absorption and accumulation of the ingested contaminant in meat and milk and high exposure (a byproduct formed 15-20% of the feed ration depending on the species). The risk assessment was refined based on literature data on metabolism in relevant animal species. Risk assessment of contaminants in byproducts is generally based on a worst-case approach, as data on carry-over of a contaminant are sparse. This may lead to erroneous estimation of health hazards. The presence of ENN B in all samples of DDGS indicates that potential impact of this emerging mycotoxin on feed and food safety deserves attention. A challenge for the future is to fill up gaps in toxicological databases and improve models for carry-over of contaminants.

Safety evaluation of an extension of use of the food enzyme thermolysin from the non-genetically modified Anoxybacillus caldiproteolyticus strain AE-TP.

The food enzyme thermolysin (EC. 3.4.24.27) is produced with the non-genetically modified Anoxybacillus caldiproteolyticus strain AE-TP by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in eight food manufacturing processes. Subsequently, the applicant has requested to extend its use to one additional process, to withdraw two processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme for use in a total of seven food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.989 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (700 mg TOS/kg bw per day, the mid-dose tested), the Panel derived a revised margin of exposure of at least 708. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Safety evaluation of an extension of use of the food enzyme oryzin from the non-genetically modified Aspergillus ochraceus strain AE-P.

The food enzyme oryzin (EC 3.4.21.63) is produced with the non-genetically modified Aspergillus ochraceus strain AE-P by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in nine food manufacturing processes. Subsequently, the applicant has requested to extend its use to one additional process, to withdraw two food processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of eight food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.354 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (1862 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 5260. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Safety evaluation of the food enzyme lysophospholipase from the genetically modified Trichoderma reesei strain DP-Nyc81.

The food enzyme lysophospholipase (2-lysophosphatidylcholine acylhydrolase, EC 3.1.1.5) is produced with the genetically modified Trichoderma reesei strain DP-Nyc81 by Genencor International B.V. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in the processing of cereals and other grains for the production of glucose syrups and other starch hydrolysates. Since residual amounts of food enzyme-total organic solids are removed during these food manufacturing processes, dietary exposure was not calculated and toxicological studies were considered unnecessary. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

Safety evaluation of an extension of use of the food enzyme 4-α-glucanotransferase from the non-genetically modified Aeribacillus pallidus strain AE-SAS.

The food enzyme 4-α-glucanotransferase (1,4-α-d-glucan:1,4-α-d-glucan 4-α-d-glycosyltransferase, EC 2.4.1.25) is produced with the non-genetically modified Aeribacillus pallidus strain AE-SAS by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in two food manufacturing processes. Subsequently, the applicant requested to extend its use to two additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme for use in a total of four food manufacturing processes. As the food enzyme-total organic solids (TOS) is removed from the final foods in one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining three processes. Dietary exposure was up to 0.040 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (900 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 22,500. Based on the data provided for the previous evaluation and the revised margin of exposure, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Safety evaluation of an extension of use of the food enzyme endo-polygalacturonase from the genetically modified Aspergillus oryzae strain AR-183.

The food enzyme endo-polygalacturonase ((1 → 4)-α-d-galacturonan glycanohydrolase EC 3.2.1.15) is produced with the genetically modified Aspergillus oryzae strain AR-183 by AB ENZYMES GmbH. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in five food manufacturing processes. Subsequently, the applicant requested to extend its use to two additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme for use in a total of seven food manufacturing processes. As the food enzyme-total organic solids (TOS) is removed from the final foods in three food manufacturing processes, the dietary exposure to the food enzyme-TOS was estimated only for the remaining four processes. Dietary exposure was up to 0.087 mg TOS/kg body weight (bw) per day in European populations. When combined with the NOAEL reported in the previous opinion (1000 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 11,494. Based on the data provided for the previous evaluation and the revised margin of exposure, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Safety evaluation of an extension of use of the food enzyme pectinesterase from the genetically modified Aspergillus oryzae strain AR-962.

The food enzyme pectinesterase (pectin pectylhydrolase; EC 3.1.1.11) is produced with the genetically modified Aspergillus oryzae strain AR-962 by AB Enzymes GmbH. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in five food manufacturing processes. Subsequently, the applicant requested to extend its use to two additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme for uses in a total of seven food manufacturing processes. As the food enzyme-total organic solids (TOS) is removed from the final foods in three food manufacturing processes, the dietary exposure to the food enzyme-TOS was estimated only for the remaining four processes. Dietary exposure was up to 0.575 mg TOS/kg body weight (bw) per day in European populations. When combined with the NOAEL reported in the previous opinion (1000 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 1739. Based on the data provided for the previous evaluation and the revised margin of exposure, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Safety evaluation of the food enzyme subtilisin from the genetically modified Bacillus licheniformis strain NZYM-CB.

The food enzyme subtilisin (EC 3.4.21.62) is produced with the genetically modified Bacillus licheniformis strain NZYM-CB by Novozymes A/S. The genetic modifications do not give rise to safety concerns. The food enzyme is considered free from viable cells of the production organism and its DNA. It is intended to be used in six food manufacturing processes. The dietary exposure to the food enzyme-TOS was estimated to be up to 0.722 mg TOS/kg body weight (bw) per day in European populations. The production strain of the food enzyme fulfils the requirements for the qualified presumption of safety approach to safety assessment. As no other concerns arising from the manufacturing process were identified, the Panel considered that toxicological tests were not required for the assessment of this food enzyme. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and 20 matches were found, including two food allergens (melon and pomegranate). The Panel considered that the risk of allergic reactions by dietary exposure cannot be excluded, particularly in individuals sensitised to melon and pomegranate, but would not exceed the risk from consumption of melon or pomegranate. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of a food enzyme with phospholipase A1 and lysophospholipase activities from the genetically modified Aspergillus niger strain PLN.

The food enzyme with phospholipase A1 (phosphatidycholine 1-acylhydrolase, EC 3.1.1.32) and lysophospholipase (2-lysophosphatidylcholine acylhydrolase, EC 3.1.1.5) activities is produced with the genetically modified Aspergillus niger strain PLN by DSM. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used for the production of refined edible fats and oils by degumming. Since residual amounts of total organic solids are removed during this process, dietary exposure was not calculated and toxicological studies were considered unnecessary for the assessment of this food enzyme. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no matches were found. The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

Safety evaluation of an extension of use of the food enzyme glucan 1,4-α-glucosidase from the non-genetically modified Rhizopus arrhizus strain AE-G.

The food enzyme glucan 1,4-α-glucosidase (4-α-d-glucan glucohydrolase; EC 3.2.1.3) is produced with the non-genetically modified Rhizopus arrhizus strain AE-G by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in one food manufacturing process. Subsequently, the applicant requested to extend its use to nine additional processes and revised the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme for uses in a total of 10 food manufacturing processes. As the food enzyme-total organic solids (TOS) is removed from the final foods in two food manufacturing processes, the dietary exposure to the food enzyme-TOS was estimated only for the remaining eight processes. Dietary exposure was up to 0.424 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level previously reported (1868 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 4406. Based on the data provided for the previous evaluation and the margin of exposure revised in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Safety evaluation of an extension of use of the food enzyme ß-amylase from the non-genetically modified Bacillus flexus strain AE-BAF.

The food enzyme ß-amylase (4-α-d-glucan maltohydrolase, EC 3.2.1.2) is produced with the non-genetically modified Bacillus flexus strain AE-BAF by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in three food manufacturing processes. Subsequently, the applicant requested to extend its use to four additional processes and revised the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme for use in a total of seven food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from the final foods in one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining six processes. The dietary exposure was estimated to be up to 0.247 mg TOS/kg body weight per day in European populations. Based on the data provided for the previous evaluation and the dietary exposure revised in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Safety evaluation of the food enzyme bacillolysin from the non-genetically modified Bacillus amyloliquefaciens strain AE-NP.

The food enzyme bacillolysin (EC 3.4.24.28) is produced with the non-genetically modified Bacillus amyloliquefaciens strain AE-NP by Amano Enzyme Inc. The production strain meets the requirements for the qualified presumption of safety (QPS) approach to safety assessment. The food enzyme is intended to be used in 14 food manufacturing processes. Since residual amounts of total organic solids (TOS) are removed in three manufacturing processes, dietary exposure was calculated only for the remaining 11 food manufacturing processes in which the food enzyme-TOS is retained. It was estimated to be up to 35.251 mg TOS/kg body weight (bw) per day in European populations. As the production strain qualifies for the QPS approach and no issue of concern arising from the production process of the food enzyme were identified, the Panel considered that no toxicological studies other than the assessment of allergenicity were necessary. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that the risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the food enzyme rennet containing chymosin and pepsin A from the abomasum of suckling calves, goats, lambs and buffaloes.

The food enzyme containing chymosin (EC 3.4.23.4) and pepsin (EC 3.4.23.1) is prepared from the abomasum of suckling calves, goats, lambs and buffaloes by Caglificio Clerici S.p.A. It is intended to be used in the production of cheese. As no concerns arise from the source of the food enzyme, from its manufacture and based on the history of safe use and consumption, the Panel considered that toxicological data were not required and no exposure assessment was necessary. The similarity of the amino acid sequences of the two proteins (chymosin and pepsin A) to those of known allergens was searched and two matches were found with respiratory allergens. The Panel considered that the risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.