Average Contamination Levels Research Articles

Determination of Salmonella spp., E. coli VTEC, Vibrio spp., and Norovirus GI-GII in Bivalve Molluscs Collected from Growing Natural Beds in Sardinia (Italy).

The aim of the present study was to evaluate the presence of Salmonella spp., verotoxigenic E. coli (VTEC), Vibrio spp., and Norovirus GI-GII in bivalve molluscs, cockles, and European grooved carpet shells (Cerastoderma spp. and Ruditapes decussatus) collected from a class B growing natural bed in Sardinia (Italy). All of the samples were analysed for Salmonella spp. detection according to European Commission Regulation (EC) 2285/2015. Detection and enumeration of Vibrio spp. were performed according to previously published methods. Presumptive identification of Vibrio spp. isolates was performed by means of conventional biochemical tests. E. coli VTEC was isolated following a direct multiplex polymerase chain reaction (PCR) screening test. Norovirus GI and GII were determined by reverse transcriptase-polymerase chain reaction (RT-PCR). No Salmonella spp. were detected. The prevalence of Vibrio spp. was 90%, and the average contamination levels were 3.19 ± 1.07 and 2.84 ± 0.31 Log10 cfu/g in cockles and European grooved carpet shells, respectively. The prevalence of E. coli VTEC was 6.6%. All of the isolates showed a complete pathogenicity profile. The presence of Norovirus was highlighted in 25% of European grooved carpet shells samples. Results showed the typical microbiological profile of bivalve molluscs collected from backwaters and confirmed the capability of shellfish to accumulate E. coli VTEC, pathogenic vibrios, and Norovirus. The presence of such pathogens in shellfish is of major concern for the safety of consumers.

Dietary exposure assessment of Chinese population to tetrabromobisphenol-A, hexabromocyclododecane and decabrominated diphenyl ether: Results of the 5th Chinese Total Diet Study

Based on the 5th Chinese Total Diet Study (TDS) carried out in 2011, the dietary exposure of Chinese population to three currently used brominated flame retardants (BFRs), tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) and decabrominated diphenyl ether (BDE-209), was estimated and the related health risks were assessed. Levels of the three BFRs were determined in 80 composite samples from four animal-origin food groups. The average levels of BFRs in various food groups ranged from 0.671 to 5.76 ng/g lipid weight (lw). The levels of TBBPA were lower than those of HBCD but higher than those of BDE-209. Moreover, average contamination levels of TBBPA and HBCD in TDS 2011 were found to be 3 to 30 times higher than those observed in TDS 2007 in the four food groups, indicating an increase in TBBPA and HBCD in the environment during 2007–2011. The average estimated daily intakes (EDIs) of TBBPA, HBCD and BDE-209 via food consumption for a “standard Chinese man” were 1.34, 1.51 and 0.96 ng/kg bw/day, respectively. Meat and meat products were found to be the major contributor to the daily dietary intake because the consumption of meat and meat products were significantly higher than that of other food groups in China. In comparison, the levels and EDIs of BFRs in this study were found to be higher than those in most studies worldwide. However, the large margin of exposure (MOE), with at least 1.1 × 105 calculated following the European Food Safety Authority (EFSA) approach, indicates that the estimated dietary exposure to these three BFRs is unlikely to raise significant health concerns. In addition, a comparison between the contamination levels of TBBPA, HBCD, BDE-209 and some novel BFRs in food samples from TDS 2011 indicated an obvious shift in the industrial production and usage pattern between PBDE and non-PBDE BFRs in China.

Electrokinetic remediation of soils contaminated by potentially toxic metals: Dedicated analytical tools for assessing the contamination baseline in a complex scenario

In order to assess the capabilities of a remediation technology, and to judge of its efficacy, it is necessary to evaluate the initial average contamination level of the soil, an operation that can be difficult because of the inhomogeneity of the contamination itself. The goal is even more challenging when different contaminants are present, greatly differing both in terms of nature and of concentration. By referring to an industrial site contaminated mainly by As, Cd, Cu, Pb, Sb, Tl and Zn, we present a new approach for the necessary processing of sampling data, in order to establish the pre-intervention baseline: an estimate of the average contamination has been obtained through a suitable integration of the volume underlying the distribution curve of each contaminating species. This information, otherwise not accessible by means of sampling of discrete points, is useful in evaluating the effectiveness of the remediation technology under investigation, and can also be considered for other reclamation approaches as well. Since “chemometrically acceptable” results are typically achieved by increasing the number of samples (with related analytical investments), the proposed approach can help keep low these ancillary costs, while providing results that are more reliable.

Fusarium species identification and fumonisin production in maize kernels from Shandong Province, China, from 2012 to 2014

ABSTRACTA total of 225 maize kernel samples were collected from Shandong Province in China from 2012 to 2014 and analysed for contamination with Fusarium spp. and fumonisins (FBs) using molecular methods and high-performance liquid chromatography with fluorescence detection. The results showed that the average incidences of Fusarium spp. in 2012, 2013 and 2014 were 23.3%, 37.1% and 36.5%, respectively, Fusarium verticillioides being the predominant species. In 2012, the average contamination level of FBs was 3071 ng g−1, which was higher than that in 2014 (2913 ng g−1) and 2013 (2072 ng g−1). Of all samples, 13% and 19% had FB contamination levels higher than 2000 and 4000 ng g−1, which are the maximum limits as set by the Food and Drug Administration of the United States and the European Commission, respectively. Therefore, efforts should be taken to minimise the potential risk of FBs to the health of humans and animals.

POSAiDA: presence of Staphylococcus aureus/MRSA and Enterococcus/VRE in Danish ambulances. A cross-sectional study.

BackgroundEvery year approximately one out of ten Danish patients contracts a healthcare associated infection (HAI). Staphylococcus aureus and Enterococcus are prominent in the group of pathogenic bacteria that underlie HAIs, causing unnecessary inconvenience and prolonging hospitalization. Bacterial colonization often occurs due to indirect patient-to-patient transmission, caused by poor hygiene compliance. This study aims to determine the level of contamination with S. aureus/MRSA and Enterococcus/VRE on presumed clean blood pressure cuffs in the Danish ambulances.MethodBlood pressure cuffs were tested for contamination with S. aureus and Enterococcus when being cleaned according to everyday guidelines in this cross-sectional study. Imprints were performed with specific agar plates after cleaning with ethanol wipes. Positive imprints were typed and antibiotic susceptibility was determined.ResultsBoth S. aureus and Enterococcus were found on blood pressure cuffs thought to be clean, however, to a limited extent. The average level of contamination by S. aureus was 0.54 CFU per 25 cm2 (SD 1.98). Minimum and maximum values ranged from 0 to 12 CFU per 25 cm2 and 10 % of the 50 samples were positive. The average level of contamination by Enterococcus was 0.06 CFU per 25 cm2 (SD 0.42). Minimum and maximum values ranged from 0 to 3 CFU per 25 cm2 and 2 % of the 50 samples were positive. All S. aureus isolates were found to be methicillin susceptible S. aureus (MSSA) and the one Enterococcus isolate was identified as Enterococcus faecalis, negative for vancomycin resistance genes.ConclusionStaphylococcus aureus and Enterococcus were detectable on equipment thought to be clean. However, all detected bacteria showed susceptibility towards methicillin or vancomycin. Findings of pathogens after cleaning may be due to cross-contamination, improper cleaning and limited effect of the currently used cleaning procedure and are thought to affect the risk of infection. Therefore, we recommend a thorough evaluation of current cleaning procedures as well as increased focus on and further research into hygiene challenges in a prehospital setting. Future studies should be performed in order to demonstrate the level of bacterial contamination in all areas of the medical service, e.g., the ambulance environment, medical equipment, staff uniform and hand hygiene. Furthermore, in order to establish evidence for different cleaning procedures in situ we recommend testing the effect of different cleaning interventions by interventional designs.

Three years of monitoring of PCDD/F, DL-PCB and NDL-PCB residues in bovine milk from Lombardy and Emilia Romagna regions (Italy): Contamination levels and human exposure assessment

In the three-years period 2012–2014, 160 cow milk samples from farms located in Lombardy and Emilia Romagna regions (Italy) were analyzed during the implementation of the Italian National Residues Monitoring Plan to assess the presence of PCDD/F, DL-PCB and NDL-PCB residues. The obtained contamination data were combined with cow milk consumption data from the Italian national dietary survey to estimate PCDD/F, DL-PCB and NDL-PCB human dietary exposure through the consumption of whole, semi skimmed and skimmed bovine milk. The exposure assessment was carried out separately for children, teenagers, adults and elderly. Average contamination levels of the analyzed samples were found to be 1.26 pg WHO-TEQ/g fat for the sum of PCDD/Fs and DL-PCBs and 9.30 ng/g fat for the sum of the 6 NDL-PCB indicators. PCB 126 was found to be the main contributor to the total WHO-TEQ. Using the upper bound approach, the estimated mean dietary intakes ranged from 0.07 pg WHO-TEQ/kg bw per day to 0.39 pg WHO-TEQ/kg bw per day for the sum of PCDD/Fs and DL-PCBs and considering exposure from whole milk. NDL-PCB mean dietary intakes resulted between 0.52 ng/kg bw per day and 2.86 ng/kg bw per day for consumption of whole milk. Children and teenagers were found to be the most exposed groups. This is the first time that Italian consumers exposure to NDL-PCBs is assessed using contamination data of cow milk produced in Italy.

경기지역 학교 단체급식소 식품 및 환경 중 식중독균 분석

Foodborne illness associated with food service establishments is an important food safety issue in Korea. In this study, foodborne pathogens (Bacillus cereus, Clostridium perfringens, Escherichia coli, pathogenic Escherichia coli, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and Vibrio parahaemolyticus) and hygiene indicator organisms [total viable cell counts (TVC), coliforms] were analyzed for food and environmental samples from foodservice establishments at schools in Gyeonggi province. Virulence factors and antimicrobial resistance of detected foodborne pathogens were also characterized. A total of 179 samples, including food (n=66), utensil (n=68), and environmental samples (n=45), were collected from eight food service establishments at schools in Gyeonggi province. Average contamination levels of TVC for foods (including raw materials) and environmental samples were 4.7 and 4.0 log CFU/g, respectively. Average contamination levels of coliforms were 2.7 and 4.0 log CFU/g for foods and environmental swab samples, respectively. B. cereus contamination was detected in food samples with an average of 2.1 log CFU/g. E. coli was detected only in raw materials, and S. aureus was positive in raw materials as well as environmental swab samples. Other foodborne pathogens were not detected in all samples. The entire B. cereus isolates possessed at least one of the diarrheal toxin genes (hblACD, nheABC, entFM, and cytK enterotoxin gene). However, ces gene encoding emetic toxin was not detected in B. cereus isolates. S. aureus isolates (n=16) contained at least one or more of the tested enterotoxin genes, except for tst gene. For E. coli and S. aureus, 92.7% and 37.5% of the isolates were susceptible against 16 and 19 antimicrobials, respectively. The analyzed microbial hazards could provide useful information for quantitative microbial risk assessment and food safety management system to control foodborne illness outbreaks in food service establishments.

Occurrence and molecular characterisation of Vibrio parahaemolyticus in crustaceans commercialised in Venice area, Italy

Infections due to the pathogenic human vibrios, Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus, are mainly associated with consumption of raw or partially cooked bivalve molluscs. At present, little is known about the presence of Vibrio species in crustaceans and the risk of vibriosis associated with the consumption of these products.The aim of the present study was to evaluate the prevalence and concentration of the main pathogenic Vibrio spp. in samples of crustaceans (n=143) commonly eaten in Italy, taking into account the effects of different variables such as crustacean species, storage conditions and geographic origin. Subsequently, the potential pathogenicity of V. parahaemolyticus strains isolated from crustaceans (n=88) was investigated, considering the classic virulence factors (tdh and trh genes) and four genes coding for relevant proteins of the type III secretion systems 2 (T3SS2α and T3SS2β).In this study, the presence of V. cholerae and V. vulnificus was never detected, whereas 40 samples (28%) were positive for V. parahaemolyticus with an overall prevalence of 41% in refrigerated products and 8% in frozen products. The highest prevalence and average contamination levels were detected in Crangon crangon (prevalence 58% and median value 3400MPN/g) and in products from the northern Adriatic Sea (35%), with the samples from the northern Venetian Lagoon reaching a median value of 1375MPN/g. While genetic analysis confirmed absence of the tdh gene, three of the isolates contained the trh gene and, simultaneously, the T3SS2β genes. Moreover three possibly clonal tdh-negative/trh-negative isolates carried the T3SS2α apparatus.The detection of both T3SS2α and T3SS2β apparatuses in V. parahaemolyticus strains isolated from crustaceans emphasised the importance of considering new genetic markers associated with virulence besides the classical factors. Moreover this study represents the first report dealing with Vibrio spp. in crustaceans in Italy, and it may provide useful information for the development of sanitary surveillance plans to prevent the risk of vibriosis in seafood consumers.

Detection of Pathogenic Yersinia Enterocolitica in Slaughtered Pigs by Cultural Methods and Real-Time Polymerase Chain Reaction.

Healthy pigs carrying pathogenic to human Yersinia enterocolitica strains are the main source of entry into slaughterhouse, where cross-contamination of carcasses can happen. The aim of this work was to determine Y. enterocolitica prevalence in slaughtered pigs, investigating the presence of carriers in relation to carcass contamination. A total of 132 pig samples (tonsils, mesenteric lymph nodes, colon content, carcass surface) were collected from 4 Sardinian slaughterhouses. All the samples were examined by the ISO 10273:2003 method, and the prevalence was also determined by direct plating on CIN Agar. Moreover, to detect the ail positive Y. enterocolitica strains in enrichment broths and isolates a real-time polymerase chain reaction (PCR) was applied. Y. enterocolitica prevalence was 19% with direct plating and 12% with enrichment methods. Carcass surfaces and tonsils prevalence was 5.30% by direct plating, and 5.3% and 2.2%, respectively, by enrichment method. Tonsil samples showed an average contamination level of 3.2×103 CFU/g, while the mean value on carcass was 8.7×102 CFU/g. An overall prevalence of 9.8% of ail positive Y. enterocolitica broths was detected by RT-PCR, that found a higher prevalence in tonsils (7.5%) with respect to cultural methods, confirming the greater sensitivity of this technique when applied for tonsils and faeces samples. The results show a relatively low pathogenic Y. enterocolitica prevalence in pigs slaughtered in Sardinia. Good hygiene measures should be applied at slaughterhouse in order to prevent the entry of carriers and control carcass contamination.

Limited survey of deoxynivalenol in wheat from different crop rotation fields in Yangtze-Huaihe river basin region of China

The food toxin, deoxynivalenol (DON) is frequently present in cereals such as wheat, barley and maize, which are infected by Fusarium asiaticum and Fusarium graminearium. Crop rotation and climatic conditions play a major role in the Fusarium infection in wheat. In this present study, a minor survey was conducted to find out the impact of crop rotation affecting the Fusarium infection leading to DON contamination in wheat samples from selected infected regions of Jiang su and An hui provinces, China, especially during harvest period in 2012. A total of 84 wheat samples from the highly Fusarium infected region were collected, of which 30, 8, 39 and 7 samples were from the fields where cotton, corn, rice, and soya bean was a rotation crop, respectively. DON concentration in wheat sample was analyzed by high performance liquid chromatography (HPLC) combined with ultraviolet detection. DON contamination in the wheat samples was 95% with the mean DON concentration of 3881.2 μg/kg from both the regions. Average DON contamination in wheat samples from cotton, soya beans, corn, and rice rotation fields were 2067.5, 2853.6, 3517.5, and 4899.3 μg/kg, respectively. Nearly 34% of the wheat samples from the cotton rotation fields were below the DON maximum tolerable limits of EU (1750.0 μg/kg) and only 3% samples were above 4000.0 μg/kg DON concentration. However, the average DON contamination level was the highest in wheat samples (4899.3 μg/kg) where rice was a rotation crop, with 64% of the samples were above 4000.0 μg/kg. The present study shows cotton could be a promising rotation crop in the regions where wheat is more prone to the infection of Fusarium sp, which may minimize the economic loss to the farmers in wheat.

Contamination profile of aflatoxin M1 residues in milk supply chain of Sindh, Pakistan.

Aflatoxin M1 (AFM1) is a potent carcinogen, teratogen and mutagen found in the milk when lactating animals consume feed contaminated with aflatoxin B1 (AFB1). In the present study, the contamination of AFM1 was evaluated in the milk supply chain of the province of Sindh, Pakistan. For the broader profiling of targeted toxin, enzyme-linked immunosorbent assay (ELISA) was used for the determination of AFM1 in both branded and non-branded milk samples. The results showed that 96.43% of samples (81 out of 84) were contaminated with AFM1 in the range of 0.01–0.76 μg/L. The average contamination level was 0.38 μg/L. The determined values of AFM1 in the collected milk samples were above the standard limit of the European Commission while 70% of the samples exceeded levels established by United States regulations. According to these results, the estimated daily intake of AFM1 for adults was determined as 3.1 ng/kg of body weight per day.

Ochratoxin A in food and urine: a nationwide Portuguese two-year study

Several toxic effects have been described after exposure to ochratoxin A (OTA), which can enter the human diet directly through food or through animal products via carry-over from contaminated feed. To assess the exposure of the Portuguese population to OTA, a study over a two-year period was conducted. It involved analysis of 472 morning urine samples from inhabitants of four regions, together with a survey of regional bread (738) and pork (254) samples. These foodstuffs are two staple foods in the Portuguese and Mediterranean diet that present a high and widespread consumption by the majority of the population. The bread samples analysed showed a low level of contamination, although the contamination range was broad and some of the samples exceeded the maximum level established in the European Union. Maize bread (broa), especially when made by mixing with rye, was the most contaminated, followed by whole grain-, rye- and wheat-based bread. However, the latter contributed more to OTA exposure, because they were more commonly consumed. Even though the occurrence was rather low, the average OTA amount in pork was relatively high compared to previous national and other surveys. The observed high within-subject variability of OTA in urine limited the use of this biomarker of exposure at the individual level, but not on a population or subgroup of subjects scale. Among the studied population, a widespread exposure was confirmed by the high frequency of OTA contamination in urine, although characterised by a low average contamination level. Independent of region or population, pork appears to be the main contributor to the daily OTA intake in Portugal. These data were clearly in contrast with previous studies showing that cereals and their derived products were the major contributors, while food of animal origin only contributed a small part to the total human dietary OTA exposure.

Silver nanoparticle-doped zirconia capillaries for enhanced bacterial filtration.

Membrane clogging and biofilm formation are the most serious problems during water filtration. Silver nanoparticle (Agnano) coatings on filtration membranes can prevent bacterial adhesion and the initiation of biofilm formation. In this study, Agnano are immobilized via direct reduction on porous zirconia capillary membranes to generate a nanocomposite material combining the advantages of ceramics being chemically, thermally and mechanically stable with nanosilver, an efficient broadband bactericide for water decontamination. The filtration of bacterial suspensions of the fecal contaminant Escherichia coli reveals highly efficient bacterial retention capacities of the capillaries of 8 log reduction values, fulfilling the requirements on safe drinking water according to the U.S. Environmental Protection Agency. Maximum bacterial loading capacities of the capillary membranes are determined to be 3 × 109 bacterial cells/750 mm2 capillary surface until back flushing is recommendable. The immobilized Agnano remain accessible and exhibit strong bactericidal properties by killing retained bacteria up to maximum bacterial loads of 6 × 108 bacterial cells/750 mm2 capillary surface and the regenerated membranes regain filtration efficiencies of 95–100%. Silver release is moderate as only 0.8% of the initial silver loading is leached during a three-day filtration experiment leading to average silver contaminant levels of 100 μg/L.

Summary: Assessing the public health risks of microbial contamination in recreational waters by satellite imagery.

Fecal contamination of recreational waters may lead to gastroenteritis, respiratory infections, dermatitis and ear infections. In addition to directly testing waters for contamination, the World Health Organization (WHO) recommends the assessment of environmental factors known to influence water quality as part of monitoring efforts. Measurement of these factors using satellite imagery may be helpful in Canada where monitoring over large areas or difficult to access locations is needed. To assess the added value of using satellite imagery as part of monitoring and managing microbial risks associated with recreational waters in Canada. Satellite images were used to calculate five environmental indices that may affect the risk of contamination of recreational waters: agricultural land, urban areas (impervious surfaces), forest and wetlands. Statistical models including these indices were then compared with the average contamination level of beaches in southern Quebec, Canada. Various satellite sensors were compared against criteria of accuracy and performance. Satellite imagery classification performed well for the study area. Two of the variables were significantly associated with higher coliform levels: agricultural land and urban areas. In the context of this assessment, the Landsat-5 sensor offered the best cost-benefit ratio. Satellite imagery can be used to identify environmental factors associated with a higher risk of fecal contamination of recreational waters in Canada and may supplement current monitoring and risk assessment efforts.

Detection and quantification of Vibrio parahaemolyticus in shellfish from Italian production areas

Vibrio parahaemolyticus is a marine microorganism, recognized as an important cause of foodborne illness particularly in Asia, South America and United States. Outbreaks are rarely reported in Europe, but they can occur unexpectedly in relation, among other reasons, to the spread of highly virulent strains. It is known that the risk is proportional to exposure levels to pathogenic V. parahaemolyticus (i.e. carrying the tdh and/or the trh genes) but currently there is a lack of occurrence data for pathogenic V. parahaemolyticus in shellfish production areas of the Member States. In this study a total of 147 samples of bivalve molluscs, from harvesting areas of two Italian regions (Sardinia and Veneto) were analyzed for Escherichia coli and salmonella, according to Reg 2073/2005, and for detection and enumeration of total and toxigenic V. parahaemolyticus strains using a new DNA colony hybridization method. Environmental parameters (water temperature and salinity) were also recorded. Results of E. coli were consistently in agreement with the legislation limits for the harvesting class of origin and Salmonella was detected only in one sample. The average contamination levels for total V. parahaemolyticus were 84 and 73CFU/g respectively for Sardinia and Veneto, with the highest value reaching 8.7×103CFU/g. Nineteen samples (12.9%) resulted positive for the presence of potentially pathogenic V. parahaemolyticus strains, with levels ranging between 10 and 120CFU/g and most of the positive samples (n=17) showing values equal or below 20CFU/g. A significant correlation (r=0.41) was found between water temperature and V. parahaemolyticus levels, as well as with isolation frequency.The data provided in this study on contamination levels of total and potentially pathogenic V. parahaemolyticus, seasonal distribution and correlation with water temperature, will help in defining appropriate monitoring programs and post-harvest policies for this hazard, improving the management of the harvesting areas and the safety of bivalve molluscs.

Qualitative and quantitative assessment of viral contamination in bivalve molluscs harvested in Italy

Bivalve molluscs are a well documented source of viral infection. Further data on shellfish viral contamination are needed to implement European Regulations with sanitary measures more effective against viral pathogens. To this aim, 336 samples of bivalve molluscs (185 mussels, 66 clams, 23 oysters and 62 samples from other species) collected in harvesting areas of class A and B of four Italian Regions were analyzed for qualitative and quantitative determination of hepatitis A virus (HAV) and Norovirus (NoV) GI and GII, using real time RT-PCR.The results showed a wide diffusion of viral contamination in the shellfish production areas considered. HAV prevalence was low (0.9%) with contamination levels that varied from 5 to 7×102copies/g. On the contrary, NoV showed a high prevalence (51.5%), with a large variability according to the group considered (e.g. 47.8% for Crassostrea in Veneto, 79.7% for Mytilus in Campania, 84.6% for Tapes in Sardinia). NoV contamination affected class A and class B production areas to a different extent, with a statistically significant difference in both contamination prevalence (22.1% vs. 66.3%; p<0.0001) and quantity (average contamination level of 3.1×102 vs. 1.9×103 copies/g; p<0.05). The different species analyzed from class B harvesting areas (Mytilus, Tapes/Ruditapes and Crassostrea) showed a NoV prevalence respectively of 70.3%, 66.0% and 47.8% but comparable NoV contamination levels (between 8.4×102 and 4.9×103copies/g). Other two bivalve species considered in the study (Donax spp. and Solen spp.) showed a relevant NoV presence (40.0% and 34.4% of samples). Finally, samples analyzed before and after commercial purification treatment showed a decrease of contamination prevalence after the treatment, but inconsistent results were recorded on NoV levels.The data obtained, together with other quantitative information to estimate consumer exposure, in association with studies on dose–response and on the effectiveness of post-harvest treatments, will provide a useful tool for the definition of microbiological criteria related to the different shellfish species.

Evaluation of radioactivity concentrations from the Fukushima nuclear accident in fish products and associated risk to fish consumers

Radioactive contamination of the Pacific Ocean following the Fukushima nuclear accident has raised public concerns about seafood safety(1, 2). Many people are wondering whether fish products from the Pacific Ocean and Japan are safe to eat 2 y after the accident. There is also some concern about seafood caught locally, outside of Japan. Based on monitoring data reported in July 2013, radioactive caesium concentrations in fish products from Fukushima and adjacent prefectures are evaluated. Resulting radiation doses from annual consumption at average contamination levels and occasional fish meals at much higher levels of caesium are calculated. To put radiation doses from caesium intake in perspective, comparisons are made to doses from naturally occurring radioactive polonium commonly found in fish. Discussion and conclusions are given subsequently. The Tokyo Electric Power Company has conducted routine radioactivity measurements (134Cs and 137Cs) of various marine fish and shellfish in the ocean area within a 20-km radius of the Fukushima Daiichi Nuclear Power Station (FDNPS). Based on their posted summary on 16 August 2013(3), a total of 100 fish samples were collected from 7 to 23 July, offshore of the FDNPS and outside of its port area. The nuclide analysis report showed that 134Cs was detected in 64 samples with concentrations varying from 3.5 to 130 Bq kg−1. 137Cs was detected in 79 samples and the concentration varied from 3.6 to 260 Bq kg−1. On average, fish and shellfish caught within 20-km offshore of the FDNPS contain 12 Bq kg−1 of 134Cs and 26 Bq kg−1 of 137Cs. The Japanese Fisheries Agency (JFA), in cooperation with the relevant prefectural governments and organisations, has conducted sampling and inspections of fishery products at the major fishing ports in Fukushima and adjacent prefectures on a weekly basis to examine the possible contamination of fishery products by radioactive materials released from the FDNPS. Based on press releases made by the JFA in July 2013(4), a total of 1952 fishery products were analysed for caesium. Among them, 134Cs was found in 485 samples (25 %) and 137Cs was detected in 776 samples (40 %). The analyses were done by various institutions and the laboratory detection limits varied from <1 Bq kg−1 to ∼10 Bq kg−1. Among those samples with concentrations above detection limits, the reported 134Cs concentrations varied from 0.1 to 338 Bq kg−1 with an average of 11 Bq kg−1. The reported 137Cs concentrations varied from 0.1 to 699 Bq kg−1 and the mean of the reported values is 18 Bq kg−1. The highest concentrations (338 Bq kg−1 for 134Cs and 699 Bq kg−1 for 137Cs) were reported on 11 July from a sample of sea bass, offshore of Hitachi city. When averaged over all 1952 samples (with zero concentration for those below the detection limit), fish products from a broad ocean area in eastern Japan contain on average 3 Bq kg−1 of 134Cs and 7 Bq kg−1 of 137Cs. Naturally occurring radionuclides exist in the environment in the air we breathe and in the water we drink. Not surprisingly, naturally occurring radionuclides can be found in varying concentrations in fishery products. A literature review conducted by Hosseini et al.(5) revealed that the mean activity concentrations of natural occurring radionuclides in generic marine fish are 83 Bq kg−1 of 40K, followed by 30 Bq kg−1 of 210Po, 19 Bq kg−1 of 14C and 1.8 Bq kg−1 of 228Ra. Potassium is ingested in many foods that we eat and is a critically important element for proper functioning of the human body. Because the potassium content of the body is under strict homeostatic control in which the amount retained is actively regulated by the body, the 40K content in the human body is constant and not influenced by variations in environmental levels. Therefore, the effect of 40K intake from fish consumption will not be considered in the following discussion. For similar reasons, the effect of 14C will also be excluded in the subsequent dose assessment.

Efficiency of two commercial on-farm pasteurizers for inactivation of mastitis pathogens in milk intended for feeding of calves.

Two commercially available pasteurizers for on farm pasteurization of milk intended for feeding calves were tested for their efficiency to inactivate mastitis pathogens. Raw bulk tank milk of the experimental farm Schaedtbek of the Max Rubner-Institute was artificially contaminated with twelve different strains of mastitis pathogens (intended level 7-8 log10 colony forming units [cfu]/ml). The average contamination level was 7.6 log10 cfu/ml in trials with pasteurizer 1 (P1) and 7.3 log10 cfu/ml in trials with pasteurizer 2 (P2), with lowest counts for yeasts (5.1 log10 cfu/ml for P1 and P2). Average reduction rates of > 5.8 log10 cfu/ml for P1 (72 degrees C, 12 s) and > 6.2 log10 cfu/ml for P2 (64 degrees C, 35 min) revealed an appropriate efficiency of both pasteurizers for practical purposes. Pathogens surviving pasteurization (enterococci in trials with both pasteurizers and of Staphylococcus aureus and Escherichia coli with P1) demonstrate the limits of pasteurization as a function of raw milk quality and emphasize the necessity for appropriate handling of pasteurized milk to prevent excessive multiplication of microbial pathogens.

Comparative mycological analysis of spices used in meat industry

Spices are often considered as one of the possible sources of meat products contamination with toxigenic moulds. Since spices are possible source of contamination of the final product and potential producers of mycotoxins, it is necessary to estimate the degree of moulds contamination. Therefore it is necessary to conduct an adequate and continuous control of spices on presence of the moulds. The choice of a culture media to carry out mycological analysis of food is extremely important to guarantee the reliability of the analysis. This paper presents an overview of the analysis of different spices (n=15) for the presence of xerophilic moulds, by using Dichloran Rose-Bengal Chloramphenicol Agar' (Oxoid, CM 727) and 'Dichloran-Glycerol (DG18) Agar Base' (Oxoid, CM 729)., Black and white grounded pepper, were the most contaminated (3.62-3.79 log10 cfu/g) of 15 samples tested, while in the remaining samples an average contamination level of 2.7 log10 cfu/g was established.

Update of the monitoring of levels of dioxins and PCBs in food and feed

Dioxins and polychlorinated biphenyls (PCBs) are environmentally persistent substances that have been associated with human health effects. Their presence in food and feed available on the European market is monitored. A total of 13,797 samples were assessed for dioxins and dioxin-like PCBs (DL-PCBs) and 19,181 samples for non dioxin-like PCBs (NDL-PCBs). These samples were submitted between 1995 and 2010 by 26 European countries. At least one quantified congener of dioxins and DL-PCBs was found in almost all samples, whereas at least one NDL-PCB indicator was quantified in 68.4 % of the feed and 82.6 % of the food samples. “Meat from eels” and “Fish liver and derived products” contained the highest average contamination levels of both dioxins and PCBs. Levels of dioxins and DL-PCBs, and of NDL-PCBs were above the permitted maximum levels in respectively 10 % and 3 % of the food samples. Depending on the population group, defined as the combination of age class and the respective survey, average exposure to dioxins and DL-PCBs was estimated to be between 0.57 and 2.54 pg TEQWHO05/kg b.w. per day and the 95th percentile between 1.2 and 9.9 pg TEQWHO05/kg b.w. per day. Average exposure to NDL-PCB indicators was estimated to be between 4.3 and 25.7 ng/kg b.w. per day and the 95th percentile between 7.8 and 53.7 ng/kg b.w. per day. Fish, meat and dairy products appeared to be the highest contributing food groups to dietary exposure. Their relative importance depended on age and country of the consumer. A general decrease in dietary exposure of dioxins and DL-PCBs was observed between 2002–2004 and 2008–2010, estimated to be between 16.6 % and 79.3 % for the different population groups. A smaller decrease was observed for NDL-PCBs. Full compliance with legislative requirements for analysis and reporting would facilitate future Europe-wide risk assessments.