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Our study aimed to evaluate the effects of nano and chelated Fe fertilization on nutrient and heavy metals uptake and their translocation from soil to root, stem, leaf, and fruits of fresh market tomatoes (Solanum Lycopersicon, cv. Sunbrite). A completely randomized design in a factorial experiment, with two Fe sources (nano vs. chelated) applied at 0 (control), 10, 20, and 40 mg/L via drip-irrigated plasticulture, was conducted. Nutrient and heavy metals concentrations in soil, water, tomato roots, stems, leaves, and fruits were determined. Soil had higher K, Fe, Ca, Mg, P, and Mn but lower Ni, Cd, and Cr concentrations. The P, K, Fe, Cu, Mn, and Na concentrations in the roots were significantly affected by both nano and chelated Fe fertilization; however, without following a consistent pattern. Averaged across the Fe treatments, K, Ca, Mg, Fe, and P that translocated from the soil were dominated in the roots, stems, and leaves. The nutrient translocation order, from roots to fruits in response to Fe fertilization, was nano Fe (40%) > chelated Fe (37%) > control (23%). Based on the treatment index values calculated across treatments, it is evident that Fe fertilization plays a pivotal role in nutrient uptake and translocation. The use of chelated Fe at a concentration of 20 mg/L had a pronounced effect on improving the nutritional quality of the tomatoes and, by extension, their associated public health benefits. In conclusion, the chelated Fe (20 mg/L) stands out as the most preferable and effective Fe fertilization for tomatoes. [ABSTRACT FROM AUTHOR]

Objectives: to estimate the contribution of locally-grown food consumption to perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) human exposure., Design: residents of a PFAS-contaminated community of the Veneto Region (North-Eastern Italy) were categorized into two exposure groups, which refer to the period after the determination of serum levels of PFOA and PFOS conducted at baseline: 1. people drinking water filtered with double granular activated carbon (GAC) and not consuming locally-grown foods at all (reference group); 2. people drinking the same filtered water and which continue to consume only locally-grown foods. For each group, PFOA and PFOS daily intake rates (IR, ng/kg-day) were derived from measured PFOA and PFOS concentrations in treated water and local vegetable and animal food matrices. Then a one-compartment pharmacokinetic model was applied to predict PFOA and PFOS serum concentrations over time and the time needed to fall below a clinically significant threshold level of PFOA and PFOS (e.g., 20 ng/mL)., Setting and Participants: the study area included 21 municipalities and 3 provinces (Vicenza, Verona, and Padua) located in the Veneto plain. Approximately 127,000 people lived in the most PFAS-contaminated areas on 31.12.2016; those aged 9 to 65 years were invited to participate in the Health Surveillance Plan (HPS), including laboratory tests and medical examination., Main Outcomes Measures: predicted PFOA and PFOS serum levels (ng/mL) among residents in the contaminated area., Results: compared to the reference group, residents who continued to consume locally-grown foods had an approximately 24% higher IR of PFOA and PFOS and this resulted in 3 more years for their PFOA and PFOS concentrations to fall below the threshold level of 20 ng/mL., Conclusions: this study showed that the contribution of locally-grown food consumption cannot be ignored for people living in PFAS-contaminated areas.

Distance is a key constraint for animals in moving between suitable habitats, but is this also the case in staging long-distance migrating shorebirds that habitually cover thousands of kilometers during migrations? We conducted multi-year field observations, benthic prey sampling and satellite tracking, to compare how endangered great knots Calidris tenuirostris respond to the food shortage at two similarly functioning staging sites (Gaizhou and Beijingzi) in the northern Yellow Sea, China. Food availability declined by >95 % at both sites across the study period, with the intake rates of great knots declining by 87 %. However, whereas the number of great knots declined by 91 % at Gaizhou, only a 29 % decrease was seen at Beiijngzi. Satellite tracking showed that during the time when food was poor in Gaizhou, tagged great knots crossed 20 km to suitable alternative high-quality sites where food was not scarce. From Beijingzi, tagged great knots flew at least 124 km to find a good alternative. We show that longer distances to alternative sites decreased the probability of a bird leaving. Thus, habitat degradation in staging sites induced great knots to move to alternative sites, but only if such alternatives were relatively close. As staging habitats become more isolated, the negative effects of habitat degradation will be more serious due to a distance constraint on exploratory movements. This emphasizes the importance of maintaining networks of nearby high-quality refueling sites for migratory birds to provide buffers in seasons when local food conditions are lean. [ABSTRACT FROM AUTHOR]