Predicting the distribution of arsenic in groundwater by machine learning technique in two worst hit districts of Assam, India: a risk to public health

Arsenic (As) is a well-known human carcinogen and a significant chemical contaminant in groundwater. The spatial heterogeneity in the distribution of As in groundwater makes it difficult to predict the location of safe areas for tube well installations for consumption and agricultural use. Geospatial machine learning techniques have been used to predict the location of safe and unsafe areas of groundwater As contaminations. Here we used a similar machine learning approach to determine the risk and extent of As >10 ug/L in groundwater at a finer spatial resolution (250m x 250m) in two worst-hit districts of Assam, India, to advise policymakers for targeted campaigning for mitigation. Random Forest Model was employed in Python environments to predict probabilities of the occurrences of As at concentrations >10 ug/L using several intrinsic and extrinsic predictor variables. The selection of predictor variables was based on their inherent relationship with the occurrence of As in groundwater. The relationships between predictor variables and proportions of As occurrences >10 ug/L follow the well-documented processes leading to As release in groundwater. We identified extensive areas of potential As hotspots based on the probability of 0.7 for As >10 ug/L. These identified areas include areas that were not previously surveyed and extended beyond previously known As hotspots. Twenty-five percent of the land area (1,500 km2) was identified as a high-risk zone with an estimated population of 155,000 potentially consuming As through drinking water or food cooked with water containing As >10 ug/L. The ternary hazard map (i.e., high, moderate, and low risk for As >10 ug/L) could inform the policymakers to target the regions by establishing newer drinking water treatment plants and supplying safe drinking water.

INFLUENCE OF POTATO VARIETY AND TYPE OF OIL USED IN FRYING POTATOES ON ACRYLAMIDE LEVEL

French fries are very consumed food products in fast-foods, restaurants, as well in consumer households. During frying process, the chemical contaminant acrylamide is formed, which is the result of the reaction between the amino group of asparagine and the carbonyl group of reducing carbohydrates (mainly glucose, fructose and maltose). The aim of this study was to investigate the influence of potato variety (Asinaria, Marvis) and type of oil (sunflower, palm) used on the level of acrylamide formed in potatoes fried in fast-food conditions. The acrylamide content was determined by GC-MS/MS using the SPE technique. For both potato varieties, the use of sunflower oil when frying potatoes led to a higher acrylamide level (288.11 ÷ 295.86 µg/% d.m.) compared to French fries fried in palm oil (227.44 ÷ 242.82 µg/% d.m.). The acrylamide level was correlated with the content of reducing sugars in the composition of the potato variety. The Asinaria variety which had the highest content of reducing carbohydrates (3.92% d.m.) determined the highest level of acrylamide. Correlations between the level of acrylamide and color parameters L* and a* were found: as the level of acrylamide increased, the color parameter L* decreased and the parameter a* increased. The potato variety and type of oil used for frying influenced the acrylamide level formed in French fries.

Citizen Science and Food: A Review

Citizen science and food is part of a new programme of work to explore how we can involve the communities we serve when building the evidence-base on which policy decisions are made. Citizen science is an approach that can provide high volumes of data with a wide geographic spread. It is relatively quick to deploy and allows access to evidence we would ordinarily have difficulty collating. This methodology has been endorsed by the European Commission for Research, Science and Innovation. There is no one size fits all definition, but citizen science projects involves engaging with communities and asking them to be part of the project, either through engaging them in data collection or through other ways of co-creation. For participants, citizen science offers learning opportunities, the satisfaction of contributing to scientific evidence and the potential to influence policy. It can also give us data which is high in volume, has wide geographical spread, is relatively quick to deploy and that we couldn’t access any other way. Projects using these methods often involve engaging with communities and asking them to be part of the project. This can be either through working with them in data collection, or through co-creation. This report demonstrates that the research community are already undertaking numerous pieces of research that align with FSA’s evidence needs. This includes examples from the UK and other global communities. Participants in such research have collected data on topics ranging from food preparation in the home to levels of chemical contaminant in foods. The findings of this report outline that citizen science could allow the FSA to target and facilitate more systematic engagement with UK and global research communities, to help address key research priorities of the FSA.

Fish Diseases Analysis Used as Bioindicators for Water Quality and its Importance for Environmental Monitoring

Species of fish are important vehicles for the transfer of contaminants to human populations, and may show the potential exposure to pollutants. They have been used as representative taxocenosis of aquatic ecosystem biotic community and as a environmental quality assessment tool. Its use in environmental monitoring has several advantages because they are directly associated with agent stressors. The objective of this study was to relate the histopathological changes observed and to verify the significance of histological analysis as a method of histopathological evaluation in studies carried out in the area. The study also includes the importance of such type of analysis in environmental change and to efficiently measure the degree of exposure in aquatic organisms to chemical contaminant. For histological analysis the animals were fixed in 10% formaldehyde and then decalcified, dehydrated with ethyl alcohol for impregnation and paraffin embedding and cut at 5-7 µm. The sections were stained with Hematoxylin and Eosin. Several types of alterations were observed in the specimens, some of them macroscopically visible. The occurrence of this type of alteration is evidence of the presence of pollutants and/or degraded habitats of the environments and the analysis of the spatial and temporal variation of their frequency of occurrence in these environments represents an important source of evaluation and monitoring of water quality in these environments.

Combined SPRi Sensor for Simultaneous Detection of Nitrate and Ammonium in Wastewater

Water pollution is a serious problem in modern society. Agriculture, being responsible for the discharge of agrochemicals, organic matter, or drug residues, produces a huge amount of wastewater. Aquaponics has the potential to reduce both water consumption and the impact of water pollution on fish farming and plant production. In the aquatic environment, inorganic nitrogen is mostly present in the form of nitrate and ammonium ions. Nitrate, as a final product of ammonia mineralization, is the most common chemical contaminant in aquifers around the world. For continuous monitoring of nitrogen compounds in wastewater, we propose a sensor for the simultaneous detection of nitrate and ammonium. A surface plasmon resonance imaging method with enzyme-mediated detection was used. Active layers of nitrate reductase and glutamine synthetase were created on the gold surface of a biochip and tested for the sensing of nitrate and ammonium in water from an aquaponic system. The proposed sensor was applied in water samples with a concentration of NO3− and NH4+ in a range between 24–780 mg·L−1 and 0.26–120 mg·L−1, respectively, with minimal pretreatment of a sample by its dilution with a buffer prior to contact on a biochip surface.

Enzyme and lateral flow monoclonal antibody-based immunoassays to simultaneously determine spirotetramat and spirotetramat-enol in foodstuffs

Spirotetramat is employed worldwide to fight insect pests due to its high efficiency. This chemical is quickly metabolized by plants into spirotetramat-enol, so current regulations establish that both compounds must be determined in foodstuffs for monitoring purposes. Nowadays, immunochemical methods constitute rapid and cost-effective strategies for chemical contaminant analysis at trace levels. However, high-affinity binders and suitable bioconjugates are required. In this study, haptens with opposite functionalisation sites were synthesized in order to generate high-affinity monoclonal antibodies. A direct competitive enzyme-linked immunosorbent assay with an IC50 value for the sum of spirotetramat and spirotetramat-enol of 0.1 μg/L was developed using selected antibodies and a novel heterologous bioconjugate carrying a rationally-designed hapten. Studies with fortified grape, grape juice, and wine samples showed good precision and accuracy values, with limits of quantification well below the maximum residue limits. Excellent correlation of results was observed with a standard reference chromatographic method. As a step forward, a lateral flow immunoassay was developed for onsite screening analysis of spirotetramat in wine. This assay was successfully validated according to Regulation 519/2014/EU for semi-quantitative methods at concentrations in line with the legal levels of spirotetramat and spirotetramat-enol in grapes, with a satisfactory false suspect rate below 2%.

Nanocellulose: a bioadsorbent for chemical contaminant remediation

The adsorption and desorption of contaminants by nanocellulose.

Introduction to the Special Issue: New Frontiers in Acrylamide Study in Foods—Formation, Analysis and Exposure Assessment

Acrylamide is a chemical contaminant that naturally originates during the thermal processing of many foods. Since 2002, worldwide institutions with competencies in food safety have promoted activities aimed at updating knowledge for a revaluation of the risk assessment of this process contaminant. The European Food Safety Authority (EFSA) ruled in 2015 that the presence of acrylamide in foods increases the risk of developing cancer in any age group of the population. Commission Regulation (EU) 2017/2158 establishes recommended mitigation measures for the food industry and reference levels to reduce the presence of acrylamide in foods and, consequently, its harmful effects on the population. This Special Issue explores recent advances on acrylamide in foods, including a novel insight on its chemistry of formation and elimination, effective mitigation strategies, conventional and innovative monitoring techniques, risk/benefit approaches and exposure assessment, in order to enhance our understanding for this process contaminant and its dietary exposure.

Special Issue on Bioconversion, Bioaccumulation and Toxicity of Mercury in a Changing World

Mercury (Hg) is recognized as a persistent global chemical contaminant that accumulates in biota, thus being an ecological hazard, as well as a health risk to fish consumers [...]