Evaluation of performance of predictive models for deoxynivalenol in wheat

Deoxynivalenol (Vomitoxin)-Induced Anorexia Is Induced by the Release of Intestinal Hormones in Mice

Deoxynivalenol (DON), also known as vomitoxin, is a mycotoxin that can cause antifeeding and vomiting in animals. However, the mechanism of DON inducing anorexia is complicated. Studies have shown that intestinal hormones play a significant part in the anorexia caused by DON. We adopted the “modeling of acute antifeeding in mice” as the basic experimental model, and used two methods of gavage and intraperitoneal injection to explore the effect of intestinal hormones on the antifeedant response induced by DON in mice. We found that 1 and 2.5 mg/kg·bw of DON can acutely induce anorexia and increase the plasma intestinal hormones CCK, PYY, GIP, and GLP-1 in mice within 3 h. Direct injection of exogenous intestinal hormones CCK, PYY, GIP, and GLP-1 can trigger anorexia behavior in mice. Furthermore, the PYY receptor antagonist JNJ-31020028, GLP-1 receptor antagonist Exendin(9-39), CCK receptor antagonist Proglumide, GIP receptor antagonist GIP(3-30)NH₂ attenuated both intestinal hormone and DON-induced anorectic responses. These results indicate that intestinal hormones play a critical role in the anorexia response induced by DON.

Factors underlying Dutch farmers' intentions to adapt their agronomic management to reduce Fusarium species infection in wheat

Infection of wheat by Fusarium species can lead to Fusarium Head Blight (FHB) and mycotoxin contamination, thereby reducing food quality and food safety, and leading to economic losses. Agronomic management through the implementation of various pre-harvest measures can reduce the probability of Fusarium spp. infection in the wheat field. To design interventions that could stimulate wheat farmers to (further) improve their agronomic management to reduce FHB, it is key to understand farmers’ behaviour towards adapting their management. The aim of this paper was to understand the intention, underlying behavioural constructs, and beliefs of Dutch wheat farmers to adapt their agronomic management to reduce FHB and mycotoxin contamination in wheat, applying the Theory of Planned Behaviour (TPB). Data were collected from 100 Dutch wheat farmers via a questionnaire. The standard TPB analysis was extended with an assessment of the robustness of the belief results to account for the statistical validity of the analysis on TPB beliefs (i.e. to address the so-called expectancy-value muddle). Forty-six percent of the farmers had a positive intention to change their management in the next 5 years. The two behavioural constructs significantly related to this intention were attitude and social norm, whereas association with the perceived behavioural control construct was insignificant indicating that farmers did not perceive any barriers to change their behaviour. Relevant attitudinal beliefs indicated specific attributes of wheat, namely yield, quality and safety (lower mycotoxin contamination). This indicates that strengthening these beliefs—by demonstrating that a change in management will result in a higher yield and quality and lower mycotoxin levels—will result in a stronger attitude and, subsequently, a higher intention to change management. Interventions to strengthen these beliefs should preferably go by the most important referents for social norms, which were the buyers and the farmer cooperatives in this study.

Strategies for estimating human exposure to mycotoxins via food

In this review, five strategies to estimate mycotoxin exposure of a (sub-)population via food, including data collection, are discussed with the aim to identify the added values and limitations of each strategy for risk assessment of these chemicals. The well-established point estimate, observed individual mean, probabilistic and duplicate diet strategies are addressed, as well as the emerging human biomonitoring strategy. All five exposure assessment strategies allow the estimation of chronic (long-term) exposure to mycotoxins, and, with the exception of the observed individual mean strategy, also acute (short-term) exposure. Methods for data collection, i.e. food consumption surveys, food monitoring studies and total diet studies are discussed. In food monitoring studies, the driving force is often enforcement of legal limits, and, consequently, data are often generated with relatively high limits of quantification and targeted at products suspected to contain mycotoxin levels above these legal limits. Total diet studies provide a solid base for chronic exposure assessments since they provide mycotoxin levels in food based on well-defined samples and including the effect of food preparation. Duplicate diet studies and human biomonitoring studies reveal the actual exposure but often involve a restricted group of human volunteers and a limited time period. Human biomonitoring studies may also include exposure to mycotoxins from other sources than food, and exposure to modified mycotoxins that may not be detected with current analytical methods. Low limits of quantification are required for analytical methods applied for data collection to avoid large uncertainties in the exposure due to high numbers of left censored data, i.e. with levels below the limit of quantification.