Rapid Detection of Aflatoxins in Ground Maize Using Near Infrared Spectroscopy.

Aflatoxins are carcinogenic mycotoxins that may contaminate many crops and more especially maize. To protect consumers from these contaminants, many countries set up low regulatory thresholds of few µg/kg. The control of food requires time-consuming analysis for which sampling is a key step. It would therefore of key sanitary and economic relevance to develop rapid, sensitive and accurate methods that could even be applied on line at harvest, to identify batches to be excluded as soon as possible. In this study, we analyzed more than 500 maize samples taken at harvest during 3 years for their aflatoxin contamination using HPLC-MS. Among them, only 7% were contaminated but sometimes at levels largely exceeding European regulations. We demonstrate that Near InfraRed Spectroscopy (NIRS) could be of great help to classify cereal samples according to their level of aflatoxin contamination (below or higher than E.U. regulation). To build the model, all AF contaminated samples as well as an equivalent number of AF free samples were used. NIRS performance was not sufficient to quantify the toxins with adequate precision. However, its ability to discriminate naturally contaminated maize samples according to their level of contamination with aflatoxins in relation to European regulations using a quadratic PCA-DA model was excellent. Accuracy of the model was 97.4% for aflatoxin B1 and 100% for total aflatoxins.

An Agro-Climatic Approach to Developing a National Prevention Tool for Deoxynivalenol in French Maize-Growing Areas.

The levels of deoxynivalenol (DON)-a mycotoxin produced by Fusarium graminearum-in maize for food and feed are subject to European Union regulations. Obtaining a compliant harvest requires the identification of agronomic and climatic risk factors related to higher fungal contamination and DON production. A national, multiyear database for maize was created, based on field survey data collected from 2004 to 2020. This database contains information about agricultural practices, climatic sequences and DON content at harvest for a total of 2032 maize fields localized in the French maize-growing regions. A linear mixed-model approach highlighted the presence of borers, late harvest and inadequate crop residue management, normal-to-cold temperatures in March, humidity in August and the absence of a hot end of the maize development cycle with a dry August as creating conditions favoring maize contamination with DON. The various possible associations between these risky climatic conditions and agricultural practices were compared, grouped and ranked as related to very low to high DON concentrations. Some combinations may even exceed the regulatory threshold. The national prevention tool, created for producers and agricultural cooperatives, is informative and easy-to-use to control the sanitary quality of their harvest.

Dataset of analyzes performed to determine the level and timing of selected organic pollutants' inputs in sediments of the Lake of Cavazzo (Italy).

This data article presents the dataset collected for selected organic pollutants in the framework of a larger research project aimed at assessing the effects of different environmental stressors (natural and anthropogenic) in sediments of the Lake of Cavazzo, a basin of glacial origin located in a seismically active region of the Italian Eastern Alps. Information relative to sampling strategy and operations, location of sampling sites, sedimentary chronological benchmarks, and profiles of RGB (Red-Green-Blue) color code determined from high resolution photos taken at cores CAV-04 and CAV-06 are reported, together with analytical data for 15 polycyclic aromatic hydrocarbons, 21 polychlorinated biphenyls' congeners (including the non-Aroclor CB-11), 14 polybrominated diphenyl ethers' congeners, and 22 organochlorine pesticides, whose concentrations were determined by Gas Chromatography coupled both to Low-Resolution and High-Resolution Mass Spectrometry. Interpretation of this dataset is fully discussed in the companion article by Pizzini et al. (2022) and relys on the multi-proxy analysis of sediment samples presented in Polonia et al. (2021) that highlighted lake stratigraphy and major changes occurring at a decadal scale since the 1950s.

A Fumonisin Prevention Tool for Targeting and Ranking Agroclimatic Conditions Favoring Exposure in French Maize-Growing Areas.

The levels of fumonisins (FUMO)-mycotoxins produced by Fusarium verticillioides-in maize for food and feed are subject to European Union regulations. Compliance with the regulations requires the targeting of, among others, the agroclimatic factors influencing fungal contamination and FUMO production. Arvalis-Institut du végétal has created a national, multiyear database for maize, based on field survey data collected since 2003. This database contains information about agricultural practices, climatic conditions and FUMO concentrations at harvest for 738 maize fields distributed throughout French maize-growing regions. A linear mixed model approach highlights the presence of borers and the use of a late variety, high temperatures in July and October, and a water deficit during the maize cycle as creating conditions favoring maize contamination with Fusarium verticillioides. It is thus possible to target a combination of risk factors, consisting of this climatic sequence associated with agricultural practices of interest. The effects of the various possible agroclimatic combinations can be compared, grouped and classified as promoting very low to high FUMO concentrations, possibly exceeding the regulatory threshold. These findings should facilitate the creation of a national, informative and easy-to-use prevention tool for producers and agricultural cooperatives to manage the sanitary quality of their harvest.

Fusarium species and enniatin mycotoxins in wheat, durum wheat, triticale and barley harvested in France.

Contamination with enniatins A, A1, B and B1 was investigated in 1240 samples of small grain cereals (470 wheat, 260 durum wheat, 282 spring barley, 172 triticale and 56 winter barley) from the French harvests of 2012 to 2014. Associations with Fusarium avenaceum, F. tricinctum and F. poae were assessed, with the identification of Fusarium species by real-time PCR and mycotoxin quantification by LC-MS/MS. Enniatins were common in the fields sampled. Enniatin concentrations varied between years but were consistently highest on spring barley (mean values of 199 to 1316 µg/kg) and triticale (mean values from 131 to 1218 µg/kg), and lower on wheat (mean values from 47 to 142 µg/kg) and durum wheat (mean values from 55 to 596 µg/kg). The concentrations of the various enniatins were strongly correlated with each other (Pearson's correlation coefficient of 0.61 to 0.98). Enniatin B was the most frequent (68% of the total enniatin content), followed by enniatin B1 (22%), enniatin A1 (7%) and enniatin A (3%). Fusarium species were quantified by calculating arithmetic mean total DNA levels. F. tricinctum was the most abundant (0.177 pg/ng total DNA), followed by F. avenaceum (0.141 pg/ng total DNA) and F. poae (0.091 pg/ng total DNA). Total DNA levels for each species, and the predominant species varied between years and crops. Small grain cereal species (p value < 0.001), harvest year (p value = < 0.001) and the presence of F. avenaceum (p value < 0.001), F. tricinctum (p value < 0.001) or F. poae (p value = 0.017) affected enniatin content. F. tricinctum was the leading enniatin producer on durum wheat (29% to 45%) and spring barley (23 to 37%). F. avenaceum produced large amounts of enniatins on durum wheat (13% to 17%) and wheat (1% to 18%) and was the leading producer on triticale (30% to 55%). F. poae made a minor contribution on all crops, never accounting for more than 2% of total enniatin content. Enniatins are, thus, highly prevalent in French small grain cereals and are mostly produced by F. avenaceum and F. tricinctum.

Occurrence and Identification of Aspergillus Section Flavi in the Context of the Emergence of Aflatoxins in French Maize.

Aflatoxins (AFs) are secondary metabolites produced by Aspergillus section Flavi during their development, particularly in maize. It is widely accepted that AFB1 is a major contaminant in regions where hot climate conditions favor the development of aflatoxigenic species. Global warming could lead to the appearance of AFs in maize produced in Europe. This was the case in 2015, in France, when the exceptionally hot and dry climatic conditions were favorable for AF production. Our survey revealed AF contamination of 6% (n = 114) of maize field samples and of 15% (n = 81) of maize silo samples analyzed. To understand the origin of the contamination, we characterized the mycoflora in contaminated samples and in samples produced in the same geographic and climatic conditions but with no AFs. A special focus was placed on Aspergillus section Flavi. A total of 67 strains of Aspergillus section Flavi were isolated from the samples. As expected, the strains were observed in all AF+ samples and, remarkably, also in almost 40% of AF- samples, demonstrating the presence of these potent toxin producers in fields in France. A. flavus was the most frequent species of the section Flavi (69% of the strains). But surprisingly, A. parasiticus was also a frequent contaminant (28% of the strains), mostly isolated from AF+ samples. This finding is in agreement with the presence of AFG in most of those samples.