Elemental distribution in summer fruits of Pakistan

Different sources of irrigation water affect heavy metal accumulation in soils and some properties of guava fruits

Guava is a highly nutritious fruit and widely grown in tropical and sub-tropical regions of the world. Guava orchards are frequently irrigated with contaminated water in different regions of the world. In the present study, fruits of two guava cultivars, i.e., Gola and Surahi were collected from orchards grown in peri-urban areas of Multan, Pakistan, which were irrigated with different sources of irrigation i.e., canal water, tubewell water, and sewage water. The soil (at four different layers), water, and fruit (at harvesting) samples were collected from the orchards for their physical, chemical, and heavy metal analysis. The results revealed that sewage water contained more concentrations of copper (Cu), zinc (Zn), and nickel (Ni) compared to tubewell and canal water. The soil irrigated with sewage water also contained the highest copper, nickel, and zinc contents, while tubewell water-irrigated soils contained the lowest copper, nickel, and zinc contents. As regards different soil layers, the top soil layer (0-15 cm) contained the maximum copper, nickel, and zinc contents. In contrast, the minimum copper, nickel, and zinc contents were estimated in the soil layer of 46-60 cm depth. The different physiological parameters of guava leaves i.e., photosynthesis (A_net), stomatal conductance (gs), transpiration (E), leaf chlorophyll fluorescence in light (Fv'/Fm') and in dark-acclimated (Fv/Fm), and non-photochemical quenching in dark-acclimated (NPQ) were decreased with sewage water irrigation. Furthermore, the sources of irrigation water significantly altered the different physical and chemical properties of the fruits. It is concluded that sewage water improved the physico-chemical properties of fruits but these also had high concentration of Cu, Ni, and Zn. The cadmium (Cd) was not detected in the fruits of guava cultivars, soils and in different sources of irrigation water. Furthermore, the soil irrigated with sewage water also had high contents of Cu, Ni, and Zn.

Irrigation water of different sources affects fruit quality attributes and heavy metals contents of un-grafted and commercial mango cultivars

In peri-urban areas, waste water is used to irrigate orchards due to scarcity of fresh water which increases heavy metals contents in soils, leaves and fruits. Due to excessive waste water irrigations, heavy metals enter into the food chain, which eventually causes metabolic disorders in humans. The present study was envisaged to investigate the effects of canal, tubewell and sewage water on the quality of mango fruits and heavy metals accumulation in soils, leaves and fruits. Leaf and fruit samples from an un-grafted (Desi mango) and six commercial cultivars of mango (Anwar Rataul, Aman Dusehri, Sufaid Chaunsa, Samar Bahisht Chaunsa, Kala Chaunsa and Anwar Rataul Late) grafted on Desi mango were collected from different mango orchards located in peri-urban areas of Multan (Pakistan) and analyzed for some physico-chemical attributes and heavy metals contents. Soil samples were also taken from these orchards irrigated with different water sources to assess the soils' heavy metals status. A significant variation was observed among the mango cultivars for their physico-chemical attributes. Sewage water irrigation improved total soluble solids (TSS), titratable acidity, ascorbic acid content, total phenolics, total carotenoids, total flavonoids and antioxidant activity of mango fruits. However, it did not affect fruit weight and shelf life. Among the heavy metals, copper and nickel contents were found in greater amounts in soils, leaves and fruits of sewage water irrigated orchards than canal and tubewell water irrigated ones. However, zinc and cadmium were not detected in any soil, water, leaf or fruit sample. The interaction among the sources of irrigation and the mango cultivars was significant for copper accumulation in different soil layers, copper and nickel accumulation in leaves of different mango cultivars, and fruit weight, titratable acidity, ascorbic acid content, total flavonoids and shelf life of mango fruits.

Assessment of Essential and Potentially Toxic Elements and Possible Health Risks in Hylocereus undatus and Punica granatum

This study evaluates essential and toxic element contents in dragon (Hylocereus undatus (Haworth) Britton and Rose) and pomegranate (Punica granatum L.) and possible health risks through the consumption of these fruits. Total concentrations of 15 chemical elements (Al, Br, Ca, Cd, Cl, Cr, Cu, Fe, Hg, K, Mn, Na, Ni, Pb, and Zn) were determined by instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS) techniques. This study indicates that these fruits are a vital source of essential elements for human health. It is observed that Pb concentrations were higher in both fruits whereas Cd concentrations were slightly higher than WHO/FAO tolerable levels only in pomegranate. The estimated daily intake (EDI) of the chemical elements was within the maximum tolerable daily intake (MTDI) values. Furthermore, target hazard quotient (THQ) values were also within the safe level (THQ < 1). However, the calculated target carcinogenic risk (TCR) values of Cd for pomegranate and Cr for dragon fruit were higher than the maximum limit (1.0 × 10^-4) for children. Finally, this study will create public awareness about micronutrient contents as well as metal contaminations of the studied fruits.

Heavy metals in jujubes and their potential health risks to the adult consumers in Xinjiang province, China

The concentrations of seven heavy metals (HMs) in jujube samples collected from Hetian region (HTR), Hami region (HMR), Erkesu region (ESR), Bayikuleng region (BLR), and Turpan region (TUR) were determined by inductively coupled mass spectrometry (ICP-MS). The accuracy and precision of the analytical method were confirmed by the certified reference material (GBW 07605). In general, the concentration of iron was higher than those of the other six metals in the investigated jujube samples. The Hazard Quotient (HQ) and Hazard Index (HI) were calculated to evaluate the noncarcinogenic health risk from individual metal and combined metals due to the dietary intakes via consumption of jujube. Both HQ and HI levels were far below 1, suggesting no noncarcinogenic risks for Xinjiang adults under the current consumption rates of the jujubes. Among the jujubes from five different regions, BLR jujube had the highest HQ and HI. Fe and As were the most concerning HMs in the investigated jujube samples due to their higher relative contributions to HIs.

Trace element levels in some dried fruit samples from Turkey

Trace element levels in nine different dried fruit samples from Kayseri, Turkey were determined by flame atomic absorption spectrometry after dry and wet digestion methods. Good accuracy was assured by the analysis of standard reference material (NIST-SRM 1515-Apple Leaves). The contents of trace elements in the samples were determined in the ranges of 1.68-4.52, 0.6-9.4, 5.5-12.4, 6.76-64.1, 4.74-25.5, 0.2-1.78, 0.8-6.17 and 0.1-0.81 microg/g for copper, nickel, lead, iron, manganese, cobalt, chromium and cadmium, respectively. The highest copper content was 4.52 microg/g in black grape, highest nickel content was 9.4 microg/g in black plum, highest lead content was 12.4 microg/g in apricot, highest iron content was 64.1 microg/g in apricot, highest manganese content was 25.5 microg/g in rose hip, highest cobalt content was 1.81 microg/g in white mulberry, highest chromium content was 6.17 microg/g in yellow plum and highest cadmium content was 0.8 microg/g in apricot and rose hip. The results were compared with the literature values.

Trace metal contents in chewing gums and candies marketed in Turkey

Cu, Ni, Pb, Fe, Mn, Cr and Cd contents were determined in 17 different brands of chewing gum and candy samples available in local markets of Kayseri, Turkey. Concentration of selected trace metals were estimated using flame atomic absorption spectrometer after dry and wet digestion methods. Out of 17 brands of chewing gums and candies analysed, four were cocoa based, two were sugar based and other were of fruit based. Copper level ranged from 0.219 to 2.455 microg/g with an average of 1.390 microg/g. Nickel ranged from 0.120 to 2.588 microg/g with an average of 0.846 microg/g. Lead level ranged from 0.031 to 2.46 microg/g with an average of 0.746 microg/g. Iron level ranged from 3.963 to 9.863 microg/g with an average of 6.618 microg/g. Manganese level ranged from 1.872 to 5.067 microg/g with an average of 3.196 microg/g. Chromium ranged from 0.740 to 6.265 microg/g with an average of 2.473 microg/g and cadmium level ranged from 0.027 to 0.825 microg/g with an average of 0.296 microg/g. Cocoa based samples were found to have higher contents of the analysed metals than sugar and fruit based samples.