Maize Consumption Research Articles

Socioeconomic and health impacts of fall armyworm in Ethiopia.

Since 2016, fall armyworm (FAW) has threatened sub-Saharan 'Africa's fragile food systems and economic performance. Yet, there is limited evidence on this transboundary pest's economic and food security impacts in the region. Additionally, the health and environmental consequences of the insecticides being used to control FAW have not been studied. This paper presents evidence on the impacts of FAW on maize production, food security, and human and environmental health. We use a combination of an agroecology-based community survey and nationally representative data from an agricultural household survey to achieve our objectives. The results indicate that the pest causes an average annual loss of 36% in maize production, reducing 0.67 million tonnes of maize (0.225 million tonnes per year) between 2017 and 2019. The total economic loss is US$ 200 million, or 0.08% of the gross domestic product. The lost production could have met the per capita maize consumption of 4 million people. We also find that insecticides to control FAW have more significant toxic effects on the environment than on humans. This paper highlights governments and development partners need to invest in sustainable FAW control strategies to reduce maize production loss, improve food security, and protect human and environmental health.

How Maize Seed Systems Can Contribute to the Control of Mycotoxigenic Fungal Infection: A Perspective

Mycotoxins are toxic secondary metabolites produced by fungi on agricultural produce. Mycotoxins can be cytotoxic, genotoxic, mutagenic, and teratogenic, and they are persistent threats to human and animal health. Consumption of mycotoxin-contaminated maize can cause cancer and even sudden death. Health hazards can also occur from consuming products from animals fed with mycotoxin-contaminated feed or forage. The main mode of spread of mycotoxigenic fungi is through air-borne spores originating from soil or plant debris, although some fungi can also spread through infected seed-to-seedling transmission, ultimately followed by contamination of the harvestable product. This perspective assesses opportunities to prevent mycotoxigenic fungal infection in maize seeds produced for sowing as an important starting point of crop contamination. A case study of Nigeria showed infection in all tested farmer-produced, seed company, and foundation seed samples. A schematic overview of the formal and informal seed systems is presented to analyze their contribution to fungal infection and mycotoxin contamination in the maize value chain, as well as to set criteria for successful control. We recommend an integrated approach to control mycotoxigenic fungal infection, including resistant varieties and other control methods during seed production, grain production, and grain storage, with an important role in maintaining seed health.

From the Atlantic coast to the lowland forests: Stable isotope analysis of the diet of forager–horticulturists in southern Brazil

AbstractIn this study, we analyze the diet of forager–horticulturalist societies of southeast South America through different isotopic markers (δ13Ccollagen, δ13Capatite, and δ15N). The economy of these populations was based on hunting, fishing, gathering, and, to a greater or lesser extent, horticulture, showing a different emphasis on each one of these options. The samples analyzed here were recovered from different environments, including the Atlantic coast, the highlands of the Brazilian plateau, and the lowland forests of the upper valleys of the Uruguay and Paraná rivers, within a general east–west sampling transect. Most of the samples correspond to individuals recovered from the Guarani and Itararé‐Taquara archeological units. We have also included a smaller sample of foragers clustered in the so‐called Vieira Tradition, perhaps with some food production, and two individuals buried in shell mounds (“sambaquis”) of the south Brazilian Atlantic coast (“Coastal Tradition”), whose economy was strongly based on marine resources and wild plants. The results indicate that, regardless of the archeological unit in question, the individuals recovered from the seashore settlements show a diet based mostly on marine protein, with a minor contribution of other resources, except in a Guarani sample, where a significant intake of maize is observed. The individuals recovered in the highlands of the Brazilian plateau (“Itararé‐Taquara”) present the highest incidence of plant consumption of the entire sample analyzed, within a C3 monoisotopic pattern, probably strongly influenced by the consumption of the araucaria pine nut, and no isotopic signals related to maize intake. Guarani samples recovered from sites located in tropical forests in the interior of the continent show an unquestionable and systematic impact of maize on the diet, in addition to an important consumption of C3 animal proteins. The individuals assigned to the so‐called Vieira Tradition show a diet based on C3 protein and both C3 and C4 lipids and carbohydrates. The latter could be related to a small consumption of maize. These results demonstrate the multidirectionality of subsistence strategies in southeastern South America during the late Holocene.

Projecting food demand in 2030: Can Uganda attain the zero hunger goal?

A precarious food security situation implies that many countries in the Global South may not achieve the United Nations Sustainable Development Goal 2 (SDG2) of zero hunger by 2030. We focus on the case of Uganda and explore food demand and food security implications for 2030, where 33% (15 million) of the population of 44 million are poor. Matooke (cooking bananas), cassava, and (sweet) potatoes are traditional foods in Uganda; however, the consumption of maize, wheat, and rice has been rising with increases in income and urbanization. Using the Living Standards Measurement Study (LSMS) datasets of Uganda, this study estimated the demand for matooke, cassava and potatoes, maize/coarse grains, wheat and rice, vegetables, and meat and fish in 2030. Our findings confirm that with increases in income and demographic changes, the demand for these food items will increase drastically. To attain SDG2 of zero hunger, as well as food and nutrition security, this study calls for further investments in Uganda's agricultural sector to enhance domestic production capacity to meet the growing demand for food.

The potential to breed a low‐protein maize for protein‐restricted diets

AbstractInborn errors of amino acid metabolism, such as phenylketonuria (PKU), are human genetic conditions that result in an inability to metabolize certain amino acids, requiring lifelong maintenance of a very restrictive low‐protein diet. In the case of PKU, this diet does not permit consumption of most maize (Zea mays L.) products, yet maize is a major part of the human diet and is especially significant in some cultures. Kernel protein content, and to a lesser extent amino acid composition, is variable in maize. Breeding maize for low kernel protein content or low amounts of specific amino acids such as phenylalanine might expand the restrictive diets and improve quality of life for people with amino acid metabolic disorders. To test the potential of breeding low‐protein‐content maize, diverse samples of hybrid or open‐pollinated cultivars and inbreds were evaluated across two locations in two years for grain protein content and amino acid composition. Consistent with previous reports, kernel protein content varied widely across maize varieties and is highly heritable in the broad sense. We found that phenylalanine content (as a proportion of grain weight) and phenylalanine composition (as a proportion of total protein) are also highly heritable in the broad sense. As previously reported, reasonably accurate estimation of protein content is possible with near‐infrared spectrophotometry, whereas measuring phenylalanine content requires a destructive, costly, and time‐consuming laboratory analysis. Because phenylalanine content was strongly correlated with total kernel protein, breeding primarily aimed at reducing grain protein content should permit efficient selection of maize cultivars sufficiently low in phenylalanine to permit broader inclusion in the PKU diet.

Evaluation of Cadmium Transfer from Soil to the Human Body Through Maize Consumption in a Cadmium Anomaly Area of Southwestern China.

Evaluating the bioavailability, bioaccessibility, and transferability of cadmium (Cd) in soil-grain-human systems is essential in areas with a Cd anomaly in the karst region of southwestern China. In the present study, the main controlling factors and prediction models for Cd transfer in a soil-grain-human system were investigated in a typical area where natural processes and anthropogenic activities interact in the karst region of southwestern China. The environmental availability of Cd (diethylenetriaminepentaacetic acid- and CaCl2 -extractable Cd [ ]) in the soil varies significantly because of the diversity of soil properties. However, Cd concentrations in the maize grain were significantly related only to the concentrations in the soil (r = 0.595, p < 0.01), indicating that soil is a good indicator for evaluating Cd uptake by maize grain. Of all the measured soil properties, the soil cation exchange capacity (CEC) and the soil calcium (Casoil ) were the most important factors influencing Cd accumulation in the soil-maize grain system. A transfer model combining , soil CEC, and Casoil was sufficiently reliable for predicting Cd accumulation in the maize grain (R2 = 0.505). Although there is room for improvement regarding the prediction performance of the chain model combining soil with Casoil to predict the bioaccessible Cd concentration in maize grain (R2 = 0.344 for the gastric phase and R2 = 0.356 for the gastrointestinal phase), our findings provide a useful reference to further explore a model that can be used for a relatively rapid and reliable estimation of dietary Cd exposure for specific regions prior to crop harvest. Environ Toxicol Chem 2021;40:2923-2934. © 2021 SETAC.

A new approach to population: Using multiple measures to estimate the population of a protohistoric village in the western Great Lakes region, USA

Prehistoric population sizes are difficult to determine, even with very well documented archaeological contexts. Within the Western Great Lakes, USA region, village population size is poorly understood due to poor preservation of village structures, excavations that did not capture the full extents of villages, and widespread destruction of archaeological sites. We combine data from geophysical surveys, historical aerial and drone-based image analyses, as well as excavation to determine the distribution of archaeological features at the protohistoric Middle Grant Creek site (11WI2739), Illinois, USA. Estimates of village population are calculated and compared using multiple measures, including structure floor area, maize storage volume, cultivation area, and maize consumption. The different estimates vary, yet they converge to indicate a population of 100 and 180 people at this agricultural village. The use of converging multiple estimates of population provides a more convincing estimate than any single source and shows how various assumptions affect different estimates. The measures employed provide a new approach to determining village size beyond traditional methods of using floor area and historic comparison, and can be used in locations where traditional measures are not available, as well as for large, dispersed sites that cannot be fully excavated.

Patterns of Antemortem Tooth Loss in Late Prehistoric West-central Tennessee

The later prehistoric subsistence-settlement pattern in the Kentucky Lake Reservoir (KLR) of northern west-central Tennessee is of interest as human occupation inexplicably terminates by AD 1450 as part of a larger regional depopulation. Antemortem tooth loss (ATL) collectively and by tooth type was identified in four site samples from the KLR. These are a Late Woodland (AD 600-900) sample (Hobbs) and three Middle Mississippian period (AD 1100- 1400) hierarchically organized and presumptively maize agriculturalist samples (Link/Slayden, Gray Farm , Thompson Village). ATL prevalence in the Hobbs sample is consistent with a native crop and seasonal foraging economy. The ATL in the Link sample is more congruent with the pre-maize Late Woodland sample than the essentially contemporaneous Gray Farm site sample. Thompson Village, a later-dated satellite community of the Gray Farm polity, exhibits significantly fewer ATL than the Gray Farm sample. This may flag climate-influenced agricultural shortfall of dietary carbohydrates later in the occupation sequence. Additionally, males in the Gray Farm site sample have significantly more ATL than males in the other two Mississippian samples. The patterns suggest regional, possibly shortfall mitigated, differences in maize intensification with a polity-specific male-focused maize consumption in the Gray Site.

Assessment of the Risk of Exposure to Aflatoxins Found in Maize (Zea mays L.) Produced in Cote d'ivoire in Ivorian Adults

Aims: The objective of this study is to estimate the health risk incurred by the Ivorian adult consumer as a result of exposure to AFB1 and the sum of aflatoxins (AFT) through the consumption of maize.&#x0D; Place and Duration of Study: During this study 375 samples of maize (grains, cobs, spathes) were taken from February 2016 to January 2017 and the analyzes were carried out at the Biotechnology Laboratory, Agriculture and Development of Biological Resources of the Félix HOUPHOUËT-BOIGNY University.&#x0D; Methodology: The detection of aflatoxins (AFB1, AFB2, AFG1, and AFG2) was performed by HPLC using the AOAC method. The risk analysis procedure was conducted according to the Codex Alimentarius risk analysis model. It consisted of a quantitative assessment. The quantitative estimation of the aflatoxin exposure was performed according to the deterministic approach.&#x0D; Results: The results indicate the presence of aflatoxins B1, B2, G1 and G2 in all forms of maize (grains, cobs, spathes) and in the five regions visited. The average concentrations of aflatoxin B1 (AFB1) and the sum of aflatoxins (AFT) ranged from 0.79 ± 0.04 µg/kg to 130.31 ± 22.56 µg/kg and from 2.63 ± 2.35 µg/kg to 169.13 ± 40.39 µg/kg, respectively. Subsequently, the Estimated Daily Intakes (EDI) by consumption of aflatoxin-contaminated maize vary according to the level of contamination. They range from 0.28±0.00 ng/kg body weight/day to 52.85±9.14 ng/kg body weight/day for AFB1 exposure. They ranged from 1.00±0.85 ng/kg body weight/day to 68.57± 16.28 ng/kg body weight/day for AFT exposure. Samples of maize grains and cobs from the Gbèkê, Poro and Hambol regions showed low daily doses below the reference values (2.028 ng/kg body weight/day and 4.056 ng/kg body weight/day). The opposite results are observed with samples (grains, ears and spathes) from Indenié-Djuablin and Gountougo.&#x0D; Conclusion: The results of the daily doses of aflatoxin exposure of these regions show a need for monitoring their production. Thus, the implementation of efficient technical itineraries throughout the maize distribution chain, both during production, post-harvest processing, and conservation will be able to guarantee a better sanitary quality of this agricultural food product.

Economic assessment of maize (Zea mays L.) – Spinach (Basella alba L.) intercropping system for improving the livelihood of smallholders’ in South-Asia

Economic assessment of maize (Zea mays L.) – Spinach (Basella alba L.) intercropping system for improving the livelihood of smallholders’ in South-Asia

A Standard Study to Estimate the Demand and Supply of Maize in Egypt

The agricultural sector is the main pillar of the Egyptian economic structure, as it represents main source of food and clothing. In addition, it contributes to of the national income and Egypt faces a deficit in agricultural production, on the other hand consumption exceeds local production, and food is considered a vital necessity for people that cannot be dispensed. This research includes the statistical assessment of the macroeconomic econometric model of the variables of demand and supply of maize during the period (2005-2019), and the problem has become one of the most important problems threatening development in Egypt It has dangerous dimensions for the agricultural sector in particular and for the Egyptian economy in general, and that Egypt is still suffering from a food gap in most food commodities in a way that threatens Egyptian food security, as the equation of imports of corn shows that the volume of imports decreases by about 0.31%, 0.70% each An increase in the import price in dollars per ton, the average per capita production of the current year by 1%, meaning that the most influential variable in the volume of imports of corn in a particular year was the import price in dollars per ton, the average per capita production. It was also found that about 65% of the changes in imports of corn are due to the change in the independent variables under study, and that the average imports, production, and consumption of maize during the same period is 10.39, 6.67, 17.60 million tons, respectively, 15 % increase in the import price causes decreased in the quantity imported by 0.31%, The average of imports, production, and consumption of maize during the same period was 10.66, 7.70 and 17.80 million tons, respectively.

Using Deer Stable Isotope Data to Test a Niche Construction Hypothesis for an Increase in Prehistoric Human Maize Consumption in the Eastern Woodlands of the United States

ABSTRACT Pollen records and macrobotanical remains indicate maize was grown minimally during the Middle Woodland (200 BCE - CE 500) in eastern North America. However, previous isotopic studies have found limited evidence of its consumption by people in archaeobotanical assemblages. Hypothetically, if deer (Odocoileus virginianus Zimmermann) were feeding on maize (Zea mays L.) in gardens prior to its adoption as a human dietary staple, this may indicate a niche construction process which would later lead to shifts in hunting strategies. This construction of garden spaces or niches has implications for decreased mobility and greater investment in garden crops. To evaluate this hypothesis in the Ohio River Valley, we measured stable nitrogen (δ15N) and carbon (δ13C) isotope compositions of bulk collagen in deer bones (N = 25) from archaeological sites spanning the Middle Woodland (200 BCE - CE 400/500) to Late Precontact (CE 1400-1630). Our hypothesis was not confirmed: little (one deer of 19) evidence for maize consumption occurred in the analyzed deer remains. Five deer of 19 did indicate the possibility of feeding in deeply wooded areas, reflecting canopy effect. Dog (Canis lupus familiaris L.) bone samples (N = 2) were also analyzed for these isotopes and one indicates some consumption of maize.

Contamination of Foods from Cameroon with Residues of 20 Halogenated Pesticides, and Health Risk of Adult Human Dietary Exposure.

(1) Background: Halogenated pesticides are abundantly used in Cameroon, but there is no information on the health risk of consumers from exposure to their residues in foods. (2) Methods: Residues of 20 halogenated pesticides were determined in 11 agricultural products collected in the 3 largest cities of Cameroon using QuEChERS extraction and gas chromatography with electron capture detector (GC-ECD), and health risk from dietary exposure was assessed. (3) Results: Organochlorines pesticides aldrin, p,p’-dichlorodiphenyl-trichloroethane (DDT) and β-hexachlorocyclohexane (β-HCH) found in 85.0%, 81.9% and 72.5% of samples, respectively, were the most frequently detected. The highest average concentrations of residues were 1.12, 0.74 and 0.39 mg/kg for methoxychlor, alachlor and β-HCH, respectively, found in chilli pepper. Chili pepper (58.9%), cowpea (56.8%), black beans (56.5%) and kidney beans (54.0%) exhibited the highest residue occurrences. Levels above the European Union maximum residue limits (MRLs) were found for all the 20 pesticides, in 40.1% of the positive analyses, and the food samples contained 14 pesticides banned in Cameroon. Chronic, acute, cumulative and carcinogenic risk assessments revealed that lifetime consumption of maize, black beans, kidney beans, groundnuts and chili pepper contaminated with aldrin, dieldrin, endrin, HCB, heptachlor, o,p’-DDT, p,p’-DDD, p,p’-DDT, p,p’-DDE and β-HCH, could pose health risks. (4) Conclusion: These results show that there is an urgent need of pesticide usage regulation, effective application of pesticide bans and management of obsolete pesticide stocks in Cameroon.

Biofortified and fortified maize consumption reduces prevalence of low milk retinol, but does not increase vitamin A stores of breastfeeding Zambian infants with adequate reserves: a randomized controlled trial

Replacement of conventional staples with biofortified or industrially fortified staples in household diets may increase maternal breast milk retinol content and vitamin A intakes from complementary foods, improving infant total body stores (TBS) of vitamin A. To determine whether biofortified or industrially fortified maize consumption by Zambian women and their breastfeeding infants could improve milk retinol concentration and infant TBS. We randomly assigned 255 lactating women and their 9-mo-old infants to a 90-d intervention providing 0 µg retinol equivalents (RE)/d as conventional maize or ∼315 µg RE/d to mothers and ∼55 µg RE/d to infants as provitamin A carotenoid-biofortified maize or retinyl palmitate-fortified maize. Outcomes were TBS, measured by retinol isotope dilution in infants (primary), and breast milk retinol, measured by HPLC in women (secondary). The intervention groups were comparable at baseline. Loss to follow-up was 10% (n=230 mother-infant pairs). Women consumed 92% of the intended 287 g/d and infants consumed 82% of the intended 50 g/d maize. The baseline geometric mean (GM) milk retinol concentration was 1.57 μmol/L (95% CI: 1.45, 1.69 μmol/L), and 24% of women had milk retinol<1.05 μmol/L. While mean milk retinol did not change in the biofortified arm (β: 0.11; 95% CI: -0.02, 0.24), the intervention reduced low milk retinol (RR:0.42; 95% CI: 0.21, 0.85). Fortified maize increased mean milk retinol (β: 0.17; 95% CI: 0.04, 0.30) and reduced the prevalence of low milk retinol (RR:0.46; 95% CI: 0.25, 0.82). The baseline GM TBS was 178 μmol (95% CI: 166, 191 μmol). This increased by 24 µmol (± 136) over the 90-d intervention period, irrespective of treatment group. Both biofortified and fortified maize consumption improved milk retinol concentration. This did not translate into greater infant TBS, most likely due to adequate TBS at baseline. This trial was registered at clinicaltrials.gov as NCT02804490.

Aflasafe SN01 is the First Biocontrol Product Approved for Aflatoxin Mitigation in Two Nations, Senegal and The Gambia.

Aflatoxin contamination is caused by Aspergillus flavus and closely related fungi. In The Gambia, aflatoxin contamination of groundnut and maize, two staple and economically important crops, is common. Groundnut and maize consumers are chronically exposed to aflatoxins, sometimes at alarming levels, and this has severe consequences on their health and productivity. Aflatoxin contamination also impedes commercialization in local and international premium markets. In neighboring Senegal, an aflatoxin biocontrol product containing four atoxigenic isolates of A. flavus, Aflasafe SN01, has been registered and is approved for commercial use in groundnut and maize. We detected that the four genotypes composing Aflasafe SN01 are also native to The Gambia. The biocontrol product was tested during two years in 129 maize and groundnut fields and compared with corresponding untreated fields cropped by smallholder farmers in The Gambia. Treated crops contained up to 100% less aflatoxins than untreated crops. A large portion of the crops could have been commercialized in premium markets due to the low aflatoxin content (in many cases no detectable aflatoxins), both at harvest and after storage. Substantial aflatoxin reductions were also achieved when commercially produced groundnut received treatment. Here we report for the first time the use and effectiveness of an aflatoxin biocontrol product registered for use in two nations. With the current scale-out and -up efforts of Aflasafe SN01, a large number of farmers, consumers, and traders in The Gambia and Senegal will obtain health, income, and trade benefits.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

A preliminary multi-isotope assessment of human mobility and diet in pre-Columbian Panama

This study uses carbon (δ13C), nitrogen (δ15N), oxygen (δ18O), and strontium (87Sr/86Sr) isotopes to infer the diets and mobility patterns of pre-Columbian humans from seven archaeological sites in Panama: Cerro Mangote, Sitio Sierra, and Cerro Juan Díaz in central Pacific Panama; Cerro Brujo and Sitio Drago along Panama’s northwest Caribbean coast; Jicarita Island in the Gulf of Chiriquí; and Pedro González Island in the Gulf of Panama. Our initial hypotheses were 1) individuals from island and coastal settlements relied more heavily on marine food than those from inland settlements, 2) dietary dependency on maize increased over time, and 3) little or no evidence exists for mobility. Generally, the results did not support these hypotheses: 1) the ecotonal community of Cerro Juan Díaz consumed large quantities of marine food, 2) maize consumption varied over time at different sites, and 3) non-local individuals appeared at multiple sites, including one possible case of an individual who had been moved after death. While this study is intended to be a preliminary analysis of human diet and mobility patterns among pre-Columbian Panamanians, it highlights the complex nature of human activities and the value of incorporating multiple lines of archaeological, osteological, geochemical, and ecological evidence for interpreting bioarchaeological data.

The occurrence of aflatoxins and human health risk estimations in randomly obtained maize from some markets in Ghana

Maize and its products are most often prone to fungal contamination especially during cultivation and storage by toxigenic fungi. Aflatoxicosis still persist in Ghana despite the numerous education on several ways of its prevention at the farm as well as its adverse health implications which are food safety concerns. A random assessment and human risk analysis was conducted on 90 maize (72 white and 18 colored) samples from markets across all the regions of Ghana. Total aflatoxins (AFtotal) and the constitutive aflatoxins (AFB1, AFB2, AFG1, and AFG2) were analyzed by High-Performance Liquid Chromatography (HPLC). Out of a total of ninety (90) samples investigated, 72 (80%) tested positive for AFB1 and the contamination levels ranged from 0.78 ± 0.04 to 339.3 ± 8.6 µg kg−1. Similarly, AFG2 was detected in only 14 (15.5%) samples, and their values ranged between 1.09 ± 0.03 and 5.51 ± 0.26 µg kg−1 while AF total ranged between 0.78 ± 0.04 and 445.01 ± 8.9 µg kg−1 constituting approximately 72 (80%). Limits of AFB1 and total aflatoxins (AFtotal) for the Ghana Standards Authority (GSA) (5 and 10 µg kg−1) and the European Food Safety Authority (EFSA) (2 and 4 µg kg−1), were used as checks. A total of 33 (41.25%) samples were above the limits for both. Risk assessments recorded for Estimated Daily Intake (EDI), Hazard Quotient (H.Q), Hazard Index (H.I), Margin of Exposure (MOE), av. Potency, and population risks ranged 0.087–0.38 μg kg−1 bw day−1, 1.5–6.9, 0.0087–0.38, 3.64–12.09, 0–0.0396 ng Aflatoxins kg−1 bw day−1 and, 3.5 × 10–1–0.015 respectively for total aflatoxins. While ranges for aflatoxins B1 (AFB1) recorded were 0.068–0.3 μg Kg bw−1 day−1, 2.43–10.64, 0.0068–0.030, 4.73–20.51, 0–0.0396 ng Aflatoxins kg−1 bw day−1 and, 2.69 × 10–3–0.012 for Estimated Daily Intake (EDI), Hazard Quotient (H.Q), Hazard Index (H.I), Margin of Exposure (MOE), Av. potency, and population risks respectively. It was deduced that although there was some observed contamination of maize across the different ecological zones, the consumption of maize (white and colored) posed no adverse health effects on the population of Ghana since computed H.I was less than 1 (< 1).

Exposure to aflatoxins and fumonisins and linear growth of children in rural Ethiopia: a longitudinal study.

We hypothesise that exposure to aflatoxins and fumonisins, measured in serum, alters protein synthesis, reducing serum protein and insulin-like growth factor 1 (IGF-1), increasing inflammation and infection, leading to child's linear growth failure. Children 6-35 months, stratified by baseline stunting, were subsampled from an intervention trial on quality protein maize consumption and evaluated at two time-points. Blood samples and anthropometric data were collected in the pre-harvest (August-September 2015) and post-harvest (February 2016) seasons in rural Ethiopia. 102 children (50 stunted and 52 non-stunted). Proportions of children exposed to aflatoxin G1, aflatoxin G2 and aflatoxin M1 were higher in the pre-harvest (8, 33 and 7, respectively) compared to post-harvest season (4, 28 and 4, respectively). The proportion of children exposed to any aflatoxin was higher in the pre-harvest than post-harvest season (51 % v. 41 %). Fumonisin exposure ranged from 0 % to 11 %. In joint statistical tests, aflatoxin exposure was associated with serum biomarkers of inflammation (C-reactive protein, α-1-glycoprotein) and protein status (transthyretin, lysine, tryptophan), IGF-1 and linear growth (all P < 0·01). However, exposure to specific aflatoxins was not significantly associated with any biomarkers or outcomes (all P > 0·05). Aflatoxin exposure among rural Ethiopian children was high, with large variation between seasons and individual aflatoxins. Fumonisin exposure was low. There was no clear association between aflatoxin exposure and protein status, inflammation or linear growth. A larger study may be needed to examine the potential biological interactions, and the assessment of aflatoxins in food is needed to determine sources of high exposure.

Prevalence of Aflatoxin- and Fumonisin-Producing Fungi Associated with Cereal Crops Grown in Zimbabwe and Their Associated Risks in a Climate Change Scenario.

In most sub-Saharan African countries, staple cereal grains harbor many fungi and some produce mycotoxins that negatively impact health and trade. Maize and three small grain cereals (sorghum, pearl millet, and finger millet) produced by smallholder farmers in Zimbabwe during 2016 and 2017 were examined for fungal community structure, and total aflatoxin (AF) and fumonisin (FM) content. A total of 800 maize and 180 small grain samples were collected at harvest and during storage from four agroecological zones. Fusarium spp. dominated the fungi associated with maize. Across crops, Aspergillus flavus constituted the main Aspergillus spp. Small grain cereals were less susceptible to both AF and FM. AF (52%) and FM (89%) prevalence was higher in maize than in small grains (13–25% for AF and 0–32% for FM). Less than 2% of small grain samples exceeded the EU regulatory limit for AF (4 µg/kg), while <10% exceeded the EU regulatory limit for FM (1000 µg/kg). For maize, 28% and 54% of samples exceeded AF and FM Codex guidance limits, respectively. Higher AF contamination occurred in the drier and hotter areas while more FM occurred in the wetter year. AF exposure risk assessment revealed that small grain consumption posed low health risks (≤0.02 liver cancer cases/100,000 persons/year) while maize consumption potentially caused higher liver cancer rates of up to 9.2 cases/100,000 persons/year depending on the locality. Additionally, FM hazard quotients from maize consumption among children and adults were high in both years, but more so in a wet year than a dry year. Adoption of AF and FM management practices throughout the maize value chain coupled with policies supporting dietary diversification are needed to protect maize consumers in Zimbabwe from AF- and FM-associated health effects. The higher risk of health burden from diseases associated with elevated concentration of mycotoxins in preferred maize during climate change events can be relieved by increased consumption of small grains.

‘White gold’ guano fertilizer drove agricultural intensification in the Atacama Desert from ad 1000

The archaeological record shows that large pre-Inca agricultural systems supported settlements for centuries around the ravines and oases of northern Chile's hyperarid Atacama Desert. This raises questions about how such productivity was achieved and sustained, and its social implications. Using isotopic data of well-preserved ancient plant remains from Atacama sites, we show a dramatic increase in crop nitrogen isotope values (δ15N) from around AD 1000. Maize was most affected, with δ15N values as high as +30‰, and human bone collagen following a similar trend; moreover, their carbon isotope values (δ13C) indicate a considerable increase in the consumption of maize at the same time. We attribute the shift to extremely high δ15N values-the highest in the world for archaeological plants-to the use of seabird guano to fertilize crops. Guano-'white gold' as it came to be called-thus sustained agricultural intensification, supporting a substantial population in an otherwise extreme environment.