Prevalence and concentration of mycotoxins in bovine feed and feed components: A global systematic review and meta-analysis.

Mycotoxins are secondary metabolites produced by fungi and identified as contaminants in animal feed. They have potentially harmful effects, including carcinogenicity, mutagenicity, and repro-toxicity in animals and humans. As a result of climate change, there is the potential for a change in the prevalence and concentration of mycotoxins in animal feed components. This necessitates an assessment of the present and emerging threats to the food supply chain from mycotoxins. This systematic review and meta-analysis study synthesised studies on mycotoxin contamination and prevalence in cattle feed components. The studies were collected from scientific databases Web of Knowledge, Scopus, and Embase between 2011 and 2022. The meta-analysis synthesised 97 studies on the prevalence and the concentration of aflatoxins, ochratoxin A, deoxynivalenol, zearalenone, fumonisin and T-2/HT-2 toxins in feed components. Aflatoxin was highly prevalent (59 %), with a concentration of 2.58-3.92 µg kg-1 in feed components. Ochratoxin A had a global prevalence of 31 % with a concentration of 5.56-12.41 µg kg-1. Deoxynivalenol had a global concentration of 233.17-327.73 µg kg-1 and a prevalence of 74 %. Zearalenone had a prevalence of 70 % and a concentration of 42.47-66.19 µg kg-1. The concentration and prevalence of fumonisins was 232.19-393.07 µg kg-1 and 65 %, respectively. The prevalence and concentration of T-2/HT-2 toxins were 45 % and 23.54-35.12 µg kg-1, respectively. The synthesised concentration of the mycotoxins in the overall feed components was lower than the regulated and guidance values set by the European Union. However, in a few cases, the 95th percentile exceeded these concentration values due to high levels of uncertainty attributed to lower sample size, and thus, need to be considered while conducting risk assessments. The study highlights climates and regions likely to be conducive to the emergence of mycotoxin risk, especially considering the potential influences of climate change.

Human health concerns regarding microplastics in the aquatic environment - From marine to food systems.

Marine plastic waste pollution is one of the most urgent global marine environmental problems worldwide. It has attracted worldwide attention from governments, the public, the scientific community, media and non-governmental organizations and has become a hot issue in current marine ecology and environmental research. This research aimed to conduct a traditional review of the current state of the art regarding microplastics (MPs) definition and characterisation, including an assessment of MPs detected in marine and food systems. The review revealed that plastic waste is not biodegraded and can only be broken down, predominantly by physical processes, into small particles of micron to nanometre size. Particles (<150 µm) can be ingested by living organisms, migrate through the intestinal wall and reach lymph nodes and other body organs. The primary pathway of human exposure to MPs has been identified as gastrointestinal ingestion (mainly seafood for the general population), pulmonary inhalation, and dermal infiltration. MPs may pollute drinking water, accumulate in the food chain, and release toxic chemicals that may cause disease, including certain cancers. Micro/nano-plastics may pose acute toxicity, (sub) chronic toxicity, carcinogenicity, genotoxicity, and developmental toxicity. In addition, nanoplastics (NPs) may pose chronic toxicity (cardiovascular toxicity, hepatotoxicity, and neurotoxicity). The toxicity of MPs/NPs primarily depends on the particle size distribution and monomeric composition/characteristics of polymers. Polyurethane (PUR), Polyacrylonitrile (PAN), Polyvinyl chloride (PVC), Epoxy resin, and Acrylonitrile-butadiene-styrene (ABS) are categorised as the most toxic polymers based on monomer toxicity. MP detection methods include combinations of spectroscopic analysis (RS and FTIR) and chromatography (TED-GC/MS). MP/NP toxicological properties and general quantitative and qualitative analysis methods used in MPs Risk Assessment (RA) are summarised. A robust dose-response model for MPs/NPs requires further investigation. This study lays the foundation for the evaluation of MP/NP risk assessment in the marine ecosystem and potential implications for human health.

Human health risk assessment of lead (Pb) through the environmental-food pathway.

Drinking water and farm-to-fork pathways have been identified as the predominant environmental pathways associated with human exposure (HE) to Pb. This study integrates a GIS-based survey of metal concentrations in soil and a probabilistic quantitative risk assessment of Pb through the food chain. The case study area was selected in the east of Ireland. A step-wise exposure assessment collated the data for Pb concentration in soil and water media, bioaccumulation of Pb in unprocessed food products, such as potatoes, carrots, green vegetables, and salad vegetables. The daily mean HE to Pb through selected food products was found to be 0.073 mg day-1, where a mean weekly exposure was estimated as 0.0065 mg kg body weight-1 week-1. Multiple risk estimates were used. Hazard Quotient (HQ), Daily Dietary Index (DDI), Daily Intake of Metal (DIM), Health Risk Index (HRI), Target Hazard Quotient (THQ) and Cancer Risk (CR) were found as 0.234 to 0.669, 0.002, 0.0002, 0.020 to 0.057, 0.234 to 0.669, and 0.00001, respectively which signify a low to moderate risk. A sensitivity analysis revealed that intake of potato is the most sensitive parameter of the model, which is positively correlated (coeff. + 0.66) followed by concentration of Pb in the arable soil (+0.49), bioaccumulation in tubers (+0.37), consumption of salad vegetables (+0.20), and consumption of green vegetables (+0.13) (top 5). A back-calculated limit of Pb in the soil (51 mg kg-1) justifies the lower threshold limit of Pb (50-300 mg kg-1) in agricultural soil set by the European Union to mitigate potential bio-transfer into food products. The study concludes there is a low to moderate risk posed by Pb, within the system boundary of the probabilistic model, and highlights the significance of limiting Pb concentrations in the vegetable producing agricultural soil.

Quantification and feed to food transfer of total and inorganic arsenic from a commercial seaweed feed.

Seaweed has a long-associated history of use as a supplemented livestock feed, providing nutrients and vitamins essential to maintaining animal health. Some species of seaweed, particularly the fucoids, are well-known accumulators of the metalloid arsenic (As). Arsenic toxicity to humans is well established even at low exposure levels and is considered a class 1 human carcinogen. As mankind's appetite for livestock produce continues to grow unabated, there is a concern that consumption of livestock produce reared on a diet supplemented with seaweed animal feed (SAF) may pose a threat to the human population due to potentially high levels of As present in seaweed. To address this concern and provide end users, including industry, consumers, policymakers and regulators with information on the exposure associated with As in commercial seaweed animal feed, the estimated daily intake (EDI) of As was calculated to evaluate potential human exposure levels. Using As data from a commercially available seaweed meal over a five-year period (2012-2017) a population exposure assessment was carried out. A Monte Carlo simulation model was developed to characterise the feed to food transfer of As from animal feed to animal produce such as beef, milk, chicken, and eggs. The model examined initial levels in seaweed, inclusion rate in animal feed, animal feeding rates and potential transfer to food produced from a supplemented diet of SAF. The analysis of seaweed animal feed showed that inorganic As was a small fraction of the total As found in seaweed meal (80:1). Statistical analysis found significant differences in the concentration of As in seaweed animal feed depending on the grain size (p < 0.001), with higher As concentrations in smaller sized grain fractions. Due to several detoxification steps and subsequent rapid excretion from the bodies of livestock, a very low carryover rate of As compounds from seaweed animal feed into livestock produce was observed. The EDI calculated in this study for the livestock produce evaluated at the 95th confidence interval was <0.01% of suggested safe levels of inorganic As intake. The threat to the general population as a result of consumption of livestock products reared on a diet consisting of SAF is found to be negligible.

Development of a semi-quantitative risk assessment model for evaluating environmental threat posed by the three first EU watch-list pharmaceuticals to urban wastewater treatment plants: An Irish case study.

Contamination of receiving waters with pharmaceutical compounds is of pressing concern. This constitutes the first study to report on the development of a semi-quantitative risk assessment (RA) model for evaluating the environmental threat posed by three EU watch list pharmaceutical compounds namely, diclofenac, 17-beta-estradiol and 17-alpha-ethinylestradiol, to aquatic ecosystems using Irish data as a case study. This RA model adopts the Irish Environmental Protection Agency Source-Pathway-Receptor concept to define relevant parameters for calculating low, medium or high risk score for each agglomeration of wastewater treatment plant (WWTP), which include catchment, treatments, operational and management factors. This RA model may potentially be used on a national scale to (i) identify WWTPs that pose a particular risk as regards releasing disproportionally high levels of these pharmaceutical compounds, and (ii) help identify priority locations for introducing or upgrading control measures (e.g. tertiary treatment, source reduction). To assess risks for these substances of emerging concern, the model was applied to 16 urban WWTPs located in different regions in Ireland that were scored for the three different compounds and ranked as low, medium or high risk. As a validation proxy, this case study used limited monitoring data recorded at some these plants receiving waters. It is envisaged that this semi-quantitative RA approach may aid other EU countries investigate and screen for potential risks where limited measured or predicted environmental pollutant concentrations and/or hydrological data are available. This model is semi-quantitative, as other factors such as influence of climate change and drug usage or prescription data will need to be considered in a future point for estimating and predicting risks.

Development of a screening tool to assess the temporal risk of pesticides leaching to groundwater using the source, target, vector approach. An Irish case study for shallow groundwater.

During this study, a groundwater screening tool was developed to assess the temporal risk of groundwater contamination from the use of pesticides. It is based on a source, vector, target approach. The method utilised in this study uses a semi-quantitative probabilistic risk assessment where the input parameters were classified and assigned a relative score from 1 to 5 (i.e. 1 = no risk and 5 = high risk). The model was parameterised by using national data and calibrated with 2 years of national pesticide groundwater monitoring data. After calibration, two specific sites were selected for model validation. Based on the presence of the source, vector and target, the evaluation indicated that the temporal risk is site specific (i.e. May to December for the country model, June to September for the Oak Park site and September for the Castledockrell site). A sensitivity analysis performed on the national scale revealed that the groundwater vulnerability category (gv), the clay content (cc%), the persistence of pesticides in soil (DT50) and the rainfall represented by wet day (wd) were the most important parameters that affected model predictions (correlation coefficients of 0.54, -0.39, 0.35 and 0.31, respectively), highlighting the importance of soil hydrogeological conditions, soil type and rainfall in influencing water model predictions. The model developed can help to identify the temporal risk from pesticides to groundwater and guide regulators in highlighting at-risk periods, therefore allowing more focused monitoring programmes.

A Monte Carlo risk assessment model for acrylamide formation in French fries.

The objective of this study is to estimate the likely human exposure to the group 2a carcinogen, acrylamide, from French fries by Irish consumers by developing a quantitative risk assessment model using Monte Carlo simulation techniques. Various stages in the French-fry-making process were modeled from initial potato harvest, storage, and processing procedures. The model was developed in Microsoft Excel with the @Risk add-on package. The model was run for 10,000 iterations using Latin hypercube sampling. The simulated mean acrylamide level in French fries was calculated to be 317 microg/kg. It was found that females are exposed to smaller levels of acrylamide than males (mean exposure of 0.20 microg/kg bw/day and 0.27 microg/kg bw/day, respectively). Although the carcinogenic potency of acrylamide is not well known, the simulated probability of exceeding the average chronic human dietary intake of 1 microg/kg bw/day (as suggested by WHO) was 0.054 and 0.029 for males and females, respectively. A sensitivity analysis highlighted the importance of the selection of appropriate cultivars with known low reducing sugar levels for French fry production. Strict control of cooking conditions (correlation coefficient of 0.42 and 0.35 for frying time and temperature, respectively) and blanching procedures (correlation coefficient -0.25) were also found to be important in ensuring minimal acrylamide formation.