Spatial variation in iodine content with relation to soil physicochemical properties in lower Himalayan region.

Topography of a place has a significant impact on soil characteristics that ultimately influence soil iodine levels. Lower Himalayan region (LHR) in Pakistan has a wide range of climatic and geological variations. Hence, an investigation was conducted to analyze the iodine concentration and other physicochemical properties of soils in two LHR districts, Haripur and Mansehra. Spatial analysis indicated a decrease in iodine levels in the mountainous regions in comparison to the flat portions of LHR. Soil samples obtained from different locations across Haripur had a stronger affinity for iodine due to variations in solubility and adsorption of iodine to soil clay components, which can be attributed to lower pH, higher organic matter, and a higher cation exchange capacity (CEC). In contrast to the plains of Haripur, elevated locations in the Mansehra district had decreased levels of iodine, along with a higher soil pH and reduced soil organic matter. The soil erosion and depletion of soil micronutrients in the hilly region of Mansehra may be attributed to the unfavorable soil conditions and excessive precipitation. Presence of clay, iron (Fe), and aluminum (Al) in the soil led to a rise in iodine levels. Iodine concentrations exhibited an inverse relationship with soil acidity. Study revealed a direct correlation between soil iodine levels and their cation exchange capacity (CEC) and clay content. This study aims to gather fundamental data for the chosen regions of LHR to address illnesses caused by iodine deficiency.

Farmers' and millers' experiences and attitudes towards the production and processing of zinc biofortified wheat in Pakistan: a mixed methods study.

Background: Zinc biofortified wheat may be a sustainable strategy to increase zinc intake in areas where fortification and dietary diversification are not feasible or are limited by household purchasing power. This convergent mixed methods study aimed to explore the farmers' and millers' experiences and attitudes towards the production and processing of zinc biofortified wheat in Pakistan. Methods: A telephone survey was conducted with farmers (n = 418) who were provided with Zincol-2016 biofortified wheat seed for the 2019-2020 growing season, as part of a wheat grain micronutrient mapping study across Punjab Province. The survey explored the farmers' experiences of growing Zincol-2016 and whether they opted to grow it again in the subsequent season. Semi-structured focus group discussions were undertaken in a separate group of farmers in Khyber Pakhtunkhwa (KP) province (n = 12) who grew Zincol-2016 for the BiZiFED2 RCT. Millers were also interviewed in KP, both those who had processed Zincol-2016 for the trial (n = 12) and those who had no experience of processing biofortified wheat (n = 12). Survey data were analyzed using descriptive statistics and transcripts of focus groups were analyzed using thematic analysis. Results: Nearly half of farmers who responded to the survey (47%) re-cultivated Zincol-2016 in the following season. The drivers for Zincol-2016 re-cultivation were seed availability (100%), grain yield and growth resistance (98%), quality of the flour from the previous harvest (97%) and nutritional benefit (94.5%). Discussions with farmers suggested that the main motivators for potential scale-up of biofortified wheat were the perceived quality of the grain, wheat, and flour. Millers saw it as an opportunity to expand their business. Farmers and millers valued the health benefits of the wheat. Challenges for scale-up include the need of additional support to produce it, unfamiliarity with the biofortification process, production costs, and external threats to the supply chain. Conclusion: Farmers and millers showed a strong implicit preference for Zincol-2016 over alternative varieties. Crop performance and product yield were the most cited motivators for growing Zincol-2016. Farmers and millers are willing to produce and process biofortified wheat if financial and educational support is provided.

Growth improvement of wheat (Triticum aestivum) and zinc biofortification using potent zinc-solubilizing bacteria.

Zinc (Zn) is an indispensable element for proper plant growth. A sizeable proportion of the inorganic Zn that is added to soil undergoes a transformation into an insoluble form. Zinc-solubilizing bacteria (ZSB) have the potential to transform the insoluble Zn into plant-accessible forms and are thus promising alternatives for Zn supplementation. The current research was aimed at investigating the Zn solubilization potential of indigenous bacterial strains and to evaluate their impact on wheat growth and Zn biofortification. A number of experiments were conducted at the National Agriculture Research Center (NARC), Islamabad, during 2020-21. A total of 69 strains were assessed for their Zn-solubilizing ability against two insoluble Zn sources (ZnO and ZnCO3) using plate assay techniques. During the qualitative assay, the solubilization index and solubilization efficiency were measured. The qualitatively selected Zn-solubilizing bacterial strains were further tested quantitatively using broth culture for Zn and phosphorus (P) solubility. Tricalcium phosphate was used as insoluble source of P. The results showed that broth culture pH was negatively correlated with Zn solubilization, i.e., ZnO (r2 = 0.88) and ZnCO3 (r2 = 0.96). Ten novel promising strains, i.e., Pantoea sp. NCCP-525, Klebsiella sp. NCCP-607, Brevibacterium sp. NCCP-622, Klebsiella sp. NCCP-623, Acinetobacter sp. NCCP-644, Alcaligenes sp. NCCP-650, Citrobacter sp. NCCP-668, Exiguobacterium sp. NCCP-673, Raoultella sp. NCCP-675, and Acinetobacter sp. NCCP-680, were selected from the ecology of Pakistan for further experimentation on wheat crop based on plant growth-promoting rhizobacteria (PGPR) traits, i.e., solubilization of Zn and P in addition to being positive for nifH and acdS genes. Before evaluating the bacterial strains for plant growth potential, a control experiment was also conducted to determine the highest critical Zn level from ZnO to wheat growth using different Zn levels (0.1, 0.05, 0.01, 0.005, and 0.001% Zn) against two wheat varieties (Wadaan-17 and Zincol-16) in sand culture under glasshouse conditions. Zinc-free Hoagland nutrients solution was used to irrigate the wheat plants. As a result, 50 mg kg-1 of Zn from ZnO was identified as the highest critical level for wheat growth. Using the critical level (50 mg kg-1 of Zn), the selected ZSB strains were inoculated alone and in consortium to the seed of wheat, with and without the use of ZnO, in sterilized sand culture. The ZSB inoculation in consortium without ZnO resulted in improved shoot length (14%), shoot fresh weight (34%), and shoot dry weight (37%); with ZnO root length (116%), it saw root fresh weight (435%), root dry weight (435%), and Zn content in the shoot (1177%) as compared to the control. Wadaan-17 performed better on growth attributes, while Zincol-16 had 5% more shoot Zn concentration. The present study concluded that the selected bacterial strains show the potential to act as ZSB and are highly efficient bio-inoculants to combat Zn deficiency, and the inoculation of these strains in consortium performed better in terms of growth and Zn solubility for wheat as compared to individual inoculation. The study further concluded that 50 mg kg-1 Zn from ZnO had no negative impact on wheat growth; however, higher concentrations hampered wheat growth.

Facile coating of micronutrient zinc for slow release urea and its agronomic effects on field grown wheat (Triticum aestivum L.).

Slow release urea has been widely tested in recent past as an effective method to enhance the crop productivity with fewer environmental concerns. However, very few research studies have been performed using micronutrients as a source of slow release of urea nitrogen. A laboratory and field study were carried out to check the agronomic effects of zinc oxide nanoparticles and its bulk salt coatings on urea prills on wheat (Triticum aestivum L.). Different concentrations of zinc oxide nanoparticles (0.25, 0.5 and 4% elemental zinc) were coated on urea prills to slow down the release rate. Bulk zinc oxide salt (ZnO) with similar concentrations was also used in parallel to make a comparison between nano and bulk salt. The SEM of zinc oxide nanoparticles clearly depicted zinc oxide nanoparticles size within a range of 50-90 nm. The XRD and FTIR spectrums also showed its characteristics peak at designated positions. Field study revealed than 0.5% zinc oxide nanoparticles coated urea boosted the crop growth and yield in comparison to the bulk zinc oxide coated urea having similar zinc concentrations, i.e., 0.25%, 0.5% and 4% elemental zinc. The plant parameters like plant height, root length, root volume, grain yield and dry matter weight were significantly increased due to application of zinc oxide nanoparticles.

The Impact of Consuming Zinc-Biofortified Wheat Flour on Haematological Indices of Zinc and Iron Status in Adolescent Girls in Rural Pakistan: A Cluster-Randomised, Double-Blind, Controlled Effectiveness Trial.

Biofortification of wheat is potentially a sustainable strategy to improve zinc intake; however, evidence of its effectiveness is needed. A household-based, double-blind, cluster-randomized controlled trial (RCT) was conducted in rural Pakistan. The primary objective was to examine the effects of consuming zinc-biofortified wheat flour on the zinc status of adolescent girls aged 10−16 years (n = 517). Households received either zinc-biofortified flour or control flour for 25 weeks; blood samples and 24-h dietary recalls were collected for mineral status and zinc intake assessment. Plasma concentrations of zinc (PZC), selenium and copper were measured via inductively coupled plasma mass spectrometry and serum ferritin (SF), transferrin receptor, alpha 1-acid glycoprotein and C-reactive protein by immunoassay. Consumption of the zinc-biofortified flour resulted in a moderate increase in intakes of zinc (1.5 mg/day) and iron (1.2 mg/day). This had no significant effect on PZC (control 641.6 ± 95.3 µg/L vs. intervention 643.8 ± 106.2 µg/L; p = 0.455), however there was an overall reduction in the rate of storage iron deficiency (SF < 15 µg/L; control 11.8% vs. 1.0% intervention). Consumption of zinc-biofortified flour increased zinc intake (21%) but was not associated with an increase in PZC. Establishing a sensitive biomarker of zinc status is an ongoing priority.

Development and testing of zinc sulfate and zinc oxide nanoparticle-coated urea fertilizer to improve N and Zn use efficiency.

Nitrogen (N) losses from conventional fertilizers in agricultural systems are very high, which can lead to serious environmental pollution with economic loss. In this study, innovative slow-release fertilizers were prepared using zinc (Zn) [nanoparticles (NPs) or in bulk], using molasses as an environmentally friendly coating. Several treatments were prepared using Zn in different concentrations (i.e., 0.25%, 0.5%, and 4% elemental Zn). The zinc oxide nanoparticles (ZnO-NPs) were prepared from zinc sulfate heptahydrate (ZnSO4·7H2O), and were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Furthermore, the Zn-loaded urea samples were tested for urea N release rate, leaching of water from soil, and crushing strength to assess the impact of coating on the final finished product. Pot experiments were conducted simultaneously to check the agronomic effects of Zn-coated slow-release urea on the growth and development of wheat (Triticum aestivum L.). The laboratory and pot results confirmed that the ZnO-NP treatments boost wheat growth and yield as a result of reduced N and Zn release. UZnNPs2 (urea coated with 0.5% ZnO-NPs and 5% molasses) demonstrated the best results among all the treatments in terms of slow nutrient release, N and Zn uptake, and grain yield. The UZnNPs2 treatment increased plant yield by 34% (i.e., 4,515 vs. 3,345 kg ha-1) relative to the uncoated prill-treated crop because of the slower release of Zn and N.

Bioassimilation of lead and zinc in rabbits fed on spinach grown on contaminated soil.

Accumulation of heavy metals in the environment can pose a potential risk to living organisms. Ingestion of leafy vegetables, containing heavy metals, is one of the main routes through which these elements enter the human body. The present study was conducted to assess the accumulation of lead (Pb) and zinc (Zn) in spinach grown on metal contaminated soil, and to examine the bioassimilation of these metals in spinach-fed rabbits. Spinach grown in the fields spiked with Pb (1000 mg kg-1 soil) and Zn (150 mg kg-1 soil), was fed to the rabbits for 14 days. Concentrations of Pb and Zn in the leaves of spinach were 39.1 and 113 mg kg-1, respectively. For the assessment of Pb and Zn concentration, blood samples were collected after 24 h, 7 days and 14 days of feeding, while the essential organs, i.e. liver and kidneys of rabbits were collected at the end of feeding trials. Concentrations (mg L-1) of Pb (3.28) and Zn (7.10) increased in blood after 24 h compared to control treatment and then decreased (Pb 1.12; Zn 3.32) to a steady state with the passage of time after 7 days. A significant increase in the concentrations of Pb (1.20%, 3.95% and 5.58%) and Zn (10.7%, 6.89% and 18.4%) as compared to control treatment was also found in liver, kidney and bones of the rabbits, respectively, which was further confirmed by multivariate analysis. The highest significant values of correlation coefficient (r) were observed for blood and bones, i.e. 0.992 followed by blood and liver, i.e. 0.989. The bioassimilation of Pb in the body of rabbits was in the order of bone > kidney > liver > blood, while for Zn the order was bone > liver > kidney > blood. The bioassimilation of Pb and Zn in the blood, essential organs and bones depicted the serious health risks associated by consuming the metal contaminated vegetable.

Determinants of women's empowerment in Pakistan: evidence from Demographic and Health Surveys, 2012-13 and 2017-18.

BACKGROUND: Women's empowerment has always remained a contested issue in the complex socio-demographic and cultural milieu of Pakistani society. Women are ranked lower than men on all vital human development indicators. Therefore, studying various determinants of women's empowerment is urgently needed in the Pakistani context. METHODS: The study empirically operationalized the concept of women's empowerment and investigated its determinants through representative secondary data taken from the Pakistan Demographic and Health Surveys among women at reproductive age (15-49 years) in 2012-13 (n = 13,558) and 2017-18 (n = 15,068). The study used simple binary logistic and multivariable regression analyses. RESULTS: The results of the binary logistic regression highlighted that almost all of the selected demographic, economic, social, and access to information variables were significantly associated with women's empowerment (p < 0.05) in both PDHS datasets. In the multivariable regression analysis, the adjusted odds ratios highlighted that reproductive-age women in higher age groups having children, with a higher level of education and wealth index, involved in skilled work, who were the head of household, and had access to information were reported to be more empowered. Results of the multivariable regression analysis conducted separately for two empowerment indicators (decision-making and ownership) corroborated the findings of the one indicator of women empowerment, except where ownership did not appear to be significantly associated with number of children and sex of household head in both data sets (2012-13 and 2017-18). CONCLUSIONS: A number of social, economic, demographic, familial, and information-exposure factors determine women's empowerment. The study proposes some evidence-based policy options to improve the status of women in Pakistan.

Biofortified Wheat Increases Dietary Zinc Intake: A Randomised Controlled Efficacy Study of Zincol-2016 in Rural Pakistan.

A new variety of zinc biofortified wheat (Zincol-2016) was released in Pakistan in 2016. The primary aim of this study was to examine the effects of consuming Zincol-2016 wheat flour on biochemical and functional markers of zinc status in a population with widespread zinc deficiency. An individually-randomised, double-blind, placebo-controlled cross over design was used. Fifty households were recruited to participate in the study, with each household included at least one woman of reproductive age (16-49 years) who was neither pregnant nor breast feeding or currently taking nutritional supplements. All households were provided with control flour for an initial 2-week baseline period, followed by the intervention period where households were randomly allocated in a 1:1 ratio to receive biofortified flour (group A; n = 25) and control flour (group B; n = 25) for 8-weeks, then switched to the alternate flour for 8-weeks. The trial has been registered with the ISRCTN (https://www.isrctn.com), ID ISRCTN83678069. The primary outcome measure was plasma zinc concentration, and the secondary outcome measures were plasma selenium and copper concentrations, plasma copper:zinc ratio and fatty acid desaturase and elongase activity indices. Nutrient intake was assessed using 24-h dietary recall interviews. Mineral concentrations in plasma were measured using inductively coupled plasma mass spectrometry and free fatty acids and sphingolipids by mass spectrometry. Linear Mixed Model regression and General Linear Model with repeated measures were used to analyse the outcomes. Based on an average flour consumption of 224 g/day, Zincol-2016 flour provided an additional daily zinc intake of between 3.0 and 6.0 mg for white and whole grain flour, respectively. No serious adverse events were reported. This resulted in significant, increase in plasma zinc concentration after 4 weeks [mean difference 41.5 µg/L, 95% CI (6.9-76.1), p = 0.02]. This was not present after 8 weeks (p = 0.6). There were no consistent significant effects of the intervention on fatty acid desaturase and elongase activity indices. Regular consumption of Zincol-2016 flour increased the daily zinc intake of women of reproductive age by 30-60%, however this was not associated with a sustained improvement in indices of zinc status.

Biodegradable Polymer Coated Granular Urea Slows Down N Release Kinetics and Improves Spinach Productivity.

Low nitrogen (N) utilization efficiency due to environmental N losses from fertilizers results in high-cost on-farm production. Urea coating with biodegradable polymers can prevent these losses by controlling the N release of fertilizers. We calculated N release kinetics of coated granular with various biodegradable polymeric materials and its impact on spinach yield and N uptake. Different formulations were used, (i) G-1: 10% starch + 5% polyvinyl alcohol (PVA) + 5% molasses; (ii) G-2: 10% starch + 5% PVA + 5% paraffin wax (PW); (iii) G-3: 5% gelatin + 10% gum arabic + 5% PW; (iv) G-4: 5% molasses + 5% gelatin + 10% gum arabic, to coat urea using a fluidized bed coater. The morphological and X-ray diffraction (XRD) analyses indicated that a uniform coating layer with no new phase formation occurred. In the G-2 treatment, maximum crushing strength (72.9 N) was achieved with a slowed-down N release rate and increased efficiency of 31%. This resulted in increased spinach dry foliage yield (47%), N uptake (60%) and apparent N recovery (ANR: 130%) from G-2 compared to uncoated urea (G-0). Therefore, coating granular urea with biodegradable polymers is a good choice to slower down the N release rate and enhances the crop yield and N utilization efficiency from urea.

Biofortification of wheat with zinc for eliminating deficiency in Pakistan: study protocol for a cluster-randomised, double-blind, controlled effectiveness study (BIZIFED2).

INTRODUCTION: Micronutrient deficiencies, commonly referred to as 'hidden hunger', affect more than two billion people worldwide, with zinc and iron-deficiency frequently reported. The aim of this study is to examine the impact of consuming zinc biofortified flour (Zincol-2016) on biochemical and functional measures of status in adolescent girls and children living in a low-resource setting in Pakistan. METHODS AND ANALYSIS: We are conducting a pragmatic, cluster-randomised, double-blind, controlled trial. A total of 482 households have been recruited from two catchment areas approximately 30-40 km distance from Peshawar. Household inclusion criteria are the presence of both an adolescent girl, aged 10-16 years, and a child aged 1-5 years. The study duration is 12 months, divided into two 6-month phases. During phase 1, all households will be provided with locally procured flour from standard varieties of wheat. During phase 2, clusters will be paired, and randomised to either the control or intervention arm of the study. The intervention arm will be provided with zinc biofortified wheat flour, with a target zinc concentration of 40 mg/kg. The control arm will be provided with locally procured wheat flour from standard varieties with an expected zinc concentration of 20 mg/kg. The primary outcome measure is plasma zinc concentration. Secondary outcomes include anthropometric measurements, biomarkers of iron and zinc status, and the presence and duration of respiratory tract infections and diarrhoea. ETHICS AND DISSEMINATION: Ethical approval was granted from the University of Central Lancashire STEMH Ethics Committee (reference number: STEMH 1014) and Khyber Medical University Ethics Committee (DIR/KMU-EB/BZ/000683). The final study methods will be published in peer-reviewed journals, alongside the study outcomes. In addition, findings will be disseminated to the scientific community via conference presentations and abstracts and communicated to the study participants through the village elders at an appropriate community forum. TRIAL REGISTRATION NUMBER: ISRCTN17107812; Pre-results.

Silicon nutrition lowers cadmium content of wheat cultivars by regulating transpiration rate and activity of antioxidant enzymes.

Given that cadmium (Cd) uptake by plants is linked to transpiration rate and activity of antioxidant enzymes and further that silicon (Si) can regulate them, it was hypothesized that improved Si nutrition could reduce Cd concentration in plants. Thus, present study was carried out to elucidate the positive effect of Si nutrition on the growth, activities of antioxidant enzymes and tissue cadmium (Cd) concentration in Cd-tolerant (Iqbal-2000) and Cd-sensitive wheat (Triticum aestivum L.) cultivars. Fifteen days after seedling transplantation, 15 µM Cd stress alone and in combination with 0.6 mM Si was applied. Silicon application improved root and shoot dry matter of Cd-sensitive cultivar Sehar-2006 while the effect was non-significant in Cd-tolerant cultivar Iqbal-2000. Silicon-treated Cd-sensitive cultivar showed marked improvements in chlorophyll content and photosynthesis, while stomatal conductance and transpiration rate decreased by Si application. Silicon treatment enhanced the activities of enzymatic antioxidants including catalase, ascorbate peroxidase, guaiacol peroxidase and superoxide dismutase and the increase was higher for Cd-tolerant cultivar Iqbal-2000. Although Si nutrition depressed malondialdehyde (MDA) content in both Cd-stressed cultivars, the response was more evident in Cd-sensitive Sehar-2006. Lower lipid peroxidation was related to Si-induced increase in antioxidant activities only in Cd-sensitive cultivar. Silicon application decreased Cd accumulation in the roots and shoots of both the cultivars. The decrease in shoot Cd was associated with a decrease in Cd uptake by roots and Cd translocation from roots to shoots. Overall, it is concluded that Si suppressed Cd contents by decreasing transpiration rate in Cd-sensitive cultivar and by increasing antioxidant activity in Cd-tolerant cultivar.

Examining the effectiveness of consuming flour made from agronomically biofortified wheat (Zincol-2016/NR-421) for improving Zn status in women in a low-resource setting in Pakistan: study protocol for a randomised, double-blind, controlled cross-over trial (BiZiFED).

INTRODUCTION: Dietary zinc (Zn) deficiency is a global problem, particularly in low-income and middle-income countries where access to rich, animal-source foods of Zn is limited due to poverty. In Pakistan, Zn deficiency affects over 40% of the adult female population, resulting in suboptimal immune status and increased likelihood of complications during pregnancy. METHODS AND ANALYSIS: We are conducting a double-blind, randomised controlled feeding study with cross-over design in a low-resource setting in Pakistan. Households were provided with flour milled from genetically and agronomically biofortified grain (Zincol-2016/NR-421) or control grain (Galaxy-2013). Fifty households were recruited. Each household included a woman aged 16-49 years who is neither pregnant nor breastfeeding, and not currently consuming nutritional supplements. These women were the primary study participants. All households were provided with control flour for an initial 2-week baseline period, followed by an 8-week intervention period where 25 households receive biofortified flour (group A) and 25 households receive control flour (group B). After this 8-week period, groups A and B crossed over, receiving control and biofortified flour respectively for 8 weeks. Tissue (blood, hair and nails) have been collected from the women at five time points: baseline, middle and end of period 1, and middle and end of period 2. ETHICS AND DISSEMINATION: Ethical approval was granted from the lead university (reference no. STEMH 697 FR) and the collaborating institution in Pakistan. The final study methods (including any modifications) will be published in peer-reviewed journals, alongside the study outcomes on completion of the data analysis. In addition, findings will be disseminated to the scientific community via conference presentations and abstracts and communicated to the study participants through the village elders at an appropriate community forum. REGISTRATION DETAILS: The trial has been registered with the ISRCTN registry, study ID ISRCTN83678069.

Health risk assessment of potentially harmful elements and dietary minerals from vegetables irrigated with untreated wastewater, Pakistan.

In the developing world, vegetables are commonly grown in suburban areas irrigated with untreated wastewater containing potentially harmful elements (PHEs). In Pakistan, there is no published work on the bioaccessibility aspect of PHEs and dietary minerals (DMs) in sewage-irrigated soil or the vegetables grown on such soils in Pakistan. Several industrial districts of Pakistan were selected for assessment of the risk associated with the ingestion of vegetables grown over sewage-irrigated soils. Both the total and bioaccessible fraction of PHEs (Cd, Co, Cr, Ni, and Pb) and DMs (Fe, Cu, Mn, Zn, Ca, Mg, and I) in soils and vegetable samples were measured. The concentrations of these PHEs and DMs in sewage-irrigated and control soils were below published upper threshold limits. However, compared to control soils, sewage irrigation over the years decreased soil pH (7.7 vs 8.1) and enhanced dissolved organic carbon (1.8 vs 0.8 %), which could enhance the phyto-availability of PHEs and DMs to crops. Of the PHEs and DMs, the highest transfer factor (soil to plant) was noted for Cd and Ca, respectively. Concentrations of PHEs in most of the sewage-irrigated vegetables were below the published upper threshold limits, except for Cd in the fruiting portion of eggplant and bell pepper (0.06-0.08 mg/kg Cd, dry weight) at three locations in Gujarat and Kasur districts. The bioaccessible fraction of PHEs can reduce the context of dietary intake measurements compared to total concentrations, but differences between both measurements were not significant for Cd. Since the soils of the sampled districts are not overly contaminated compared to control sites, vegetables grown over sewage-irrigated soils would provide an opportunity to harvest mineral-rich vegetables potentially providing consumers 62, 60, 12, 104, and 63 % higher dietary intake of Cu, Mn, Zn, Ca, and Mg, respectively. Based on Fe and vanadium correlations in vegetables, it is inferred that a significant proportion of total dietary Fe intake could be contributed by soil particles adhered to the consumable portion of vegetables. Faecal sterol ratios were used to identify and distinguish the source of faecal contamination in soils from Gujranwala, Gujarat, and Lahore districts, confirming the presence of human-derived sewage biomarkers at different stages of environmental alteration. A strong correlation of some metals with soil organic matter concentration was observed, but none with sewage biomarkers.

Valuing increased zinc (Zn) fertiliser-use in Pakistan.

BACKGROUND AND AIMS: Use of zinc (Zn) fertilisers may be cost-effective in increasing crop yields and in alleviating dietary Zn deficiency. However, Zn fertilisers are underutilised in many countries despite the widespread occurrence of Zn-deficient soils. Here, increased Zn fertiliser-use scenarios were simulated for wheat production in Punjab and Sindh Provinces, Pakistan. Inputs and outputs were valued in terms of both potential yield gains as well as health gains in the population. METHODS: The current dietary Zn deficiency risk of 23.9 % in Pakistan was based on food supply and wheat grain surveys. "Disability-adjusted life years (DALYs) lost" are a common metric of disease burden; an estimated 245,000 DALYs y-1 are lost in Punjab and Sindh due to Zn deficiency. Baseline Zn fertiliser-use of 7.3 kt y-1 ZnSO4.H2O was obtained from published and industry sources. The wheat area currently receiving Zn fertilisers, and grain yield responses of 8 and 14 % in Punjab and Sindh, respectively, were based on a recent survey of >2500 farmers. Increased grain Zn concentrations under Zn fertilisation were estimated from literature data and converted to improved Zn intake in humans and ultimately a reduction in DALYs lost. RESULTS: Application of Zn fertilisers to the area currently under wheat production in Punjab and Sindh, at current soil: foliar usage ratios, could increase dietary Zn supply from ~12.6 to 14.6 mg capita -1 d-1, and almost halve the prevalence of Zn deficiency, assuming no other changes to food consumption. Gross wheat yield could increase by 2.0 and 0.6 Mt. grain y-1 in Punjab and Sindh, respectively, representing an additional return of US$ >800 M and an annual increased grain supply of 19 kg capita -1. CONCLUSIONS: There are potential market- and subsidy-based incentives to increase Zn fertiliser-use in Pakistan. Benefit-Cost Ratios (BCRs) for yield alone are 13.3 and 17.5 for Punjab and Sindh, respectively. If each DALY is monetised at one to three fold Gross National Income per capita on purchasing power parity (GNIPPP), full adoption of Zn fertiliser for wheat provides an additional annual return of 405-1216 M International Dollars (I$) in Punjab alone, at a cost per DALY saved of I$ 461-619.

Genotypic variation in phytoremediation potential of Indian mustard exposed to nickel stress: a hydroponic study.

Ten Indian mustard (Brassica juncea L.) genotypes were screened for their nickel (Ni) phytoremediation potential under controlled environmental conditions. All ten genotypes were grown hydroponically in aqueous solution containing Ni concentrations (as nickel chloride) ranging from 0 to 50 µM and changes in plant growth, biomass and total Ni uptake were evaluated. Of the ten genotypes (viz. Agrini, BTO, Kranti, Pusa Basant, Pusa Jai Kisan, Pusa Bahar, Pusa Bold, Vardhan, Varuna, and Vaibhav), Pusa Jai Kisan was the most Ni tolerant genotype accumulating up to 1.7 µg Ni g(-1) dry weight (DW) in its aerial parts. Thus Pusa Jai Kisan had the greatest potential to become a viable candidate in the development of practical phytoremediation technologies for Ni contaminated sites.

In vitro and in vivo approaches for the measurement of oral bioavailability of lead (Pb) in contaminated soils: a review.

We reviewed the published evidence of lead (Pb) contamination of urban soils, soil Pb risk to children through hand-to-mouth activity, reduction of soil Pb bioavailability due to soil amendments, and methods to assess bioaccessibility which correlate with bioavailability of soil Pb. Feeding tests have shown that urban soils may have much lower Pb bioavailability than previously assumed. Hence bioavailability of soil Pb is the important measure for protection of public health, not total soil Pb. Chemical extraction tests (Pb bioaccessibility) have been developed which are well correlated with the results of bioavailability tests; application of these tests can save money and time compared with feeding tests. Recent findings have revealed that fractional bioaccessibility (bioaccessible compared to total) of Pb in urban soils is only 5-10% of total soil Pb, far lower than the 60% as bioavailable as food-Pb presumed by U.S.-EPA (30% absolute bioavailability used in IEUBK model).

Role of mineral nutrition in minimizing cadmium accumulation by plants.

Cadmium (Cd) is a highly toxic heavy metal for both plants and animals. The presence of Cd in agricultural soils is of great concern regarding its entry into the food chain. Cadmium enters into the soil-plant environment mainly through anthropogenic activities. Compounds of Cd are more soluble than other heavy metals, so it is more available and readily taken up by plants and accumulates in different edible plant parts through which it enters the food chain. A number of approaches are being used to minimize the entry of Cd into the food chain. Proper plant nutrition is one of the good strategies to alleviate the damaging effects of Cd on plants and to avoid its entry into the food chain. Plant nutrients play a very important role in developing plant tolerance to Cd toxicity and thus, low Cd accumulation in different plant parts. In this report, the role of some macronutrients (nitrogen, phosphorus, sulfur and calcium), micronutrients (zinc, iron and manganese), and silicon (a beneficial nutrient) has been discussed in detail as to how these nutrients play their role in decreasing Cd uptake and accumulation in crop plants.

Chemically enhanced phytoextraction of Pb by wheat in texturally different soils.

A pot study was used to examine the effects of amendments such as EDTA and elemental sulfur on the growth potential, gas exchange features, uptake and mobilization of Pb by wheat (Triticum aestivum L.) in two texturally different contaminated soils at three levels of EDTA (2, 4, 8 mmol kg(-1) dry soil) and two levels of elemental sulfur (100, 200 mmol kg(-1) dry soil). EDTA resulted in more solubilization of Pb than elemental sulfur in both soils. Application of EDTA and elemental sulfur increased shoot dry matter in the loamy sand soil, whereas in the sandy clay loam soil EDTA treated plants produced lower shoot dry matter compared to that observed with elemental sulfur. Application of EDTA 10d prior to harvest increased the amount of Pb accumulated into wheat shoots with more Pb accumulated by plants from the loamy sand than from the sandy clay loam soil. However, evaluation of the relative extraction efficiency expressed as the percentage of solubilized Pb that is subsequently also effectively accumulated by the plant shoots reveals that the relatively low efficiency does not warrant the massive mobilization induced by the environmentally persistent EDTA chelator. More modest mobilization of Pb induced by elemental sulfur and the higher relative extraction of mobilized Pb therefore deserves further attention in future research. In particular, attention needs to be paid to determining soil types in which elemental sulfur can induce significant impact on soil pH and metal mobility after application of a practically realistic dosage.