Metal Contamination Of Food Crops Research Articles

Levels of Heavy Metal in Vegetable, Fruits and Cereals Crops in Ethiopia: A Review

Heavy metal pollution of the environment through anthropogenic and natural processes are expanded in a serious problem. Heavy metals are elements in the predict table they have high atomic weight, atomic number and atomic densities higher than 4 g/cm3, among those metals lead, cadmium, zinc, mercury, arsenic, silver, chromium, copper, iron, platinum and others. Toxic heavy metal contamination of food crops is a big concern global world mainly in developing country like Ethiopia. Ultimately, heavy metal toxicity and disease in human and animals are because of conception of heavy metal contaminated soil, food and air. The huge amount environmental contamination by toxic heavy metals are dangerous because of their uptake by plants and subsequent accumulation in food crops consumed by animals and humans is deleterious to heath. There are many known source of toxic heavy metals including the nature, which releases in to the food, air and water, and human activities like fertilizer application in agricultural farm, the use of herbicides and pesticide and wastewater irrigation. Other sources of heavy metals in environment are smoking, automobile emission, industries, swage and waste disposal. Most studies showed that vegetables and other food crops consumed in Ethiopia are contaminated by heavy metals this is associated with adverse health issues such as cancer, which is currently serious in Ethiopia. It is therefore a big concern based on those issues the communities to avoid the conception of heavy metal contaminated food items. There is also need monitoring of the levels of heavy metals in food crops and precaution of heavy metal controlling methods.

Heavy metal contamination and accumulation in groundwater and food crops in Sri Lanka: a review

Heavy metal contamination in food crops and ground water lead toxic effects on living organisms through the interference of the metabolic pathways. In this paper, the prevailing scientific data, with regard to the accumulation of heavy metals in groundwater and food crops in Sri Lanka, were reviewed. Evidence revealed that the groundwater bodies in Sri Lanka are in safer level to be used for day-to-day activities with a few exceptions and however, the heavy metal accumulation in some food crops are beyond the permissible level. Chronic Kidney Disease of unknown aetiology is one of the emerging issues at present in dry zones, particularly in the North Central Province in Sri Lanka and its suspected due to the extensive use of agrochemicals which is believed to be contaminated with the heavy metals.

A Review of Heavy Metal Contamination of Food Crops in Nigeria.

Heavy metal contamination of food crops is an issue of global concern that ultimately results in toxicity and diseases in humans and animals through consumption of contaminated soils and food crops. With a population of 182 million people, Nigeria is regarded as the most populous country in Africa. The people suffer environmental pollution from high levels of heavy metal accumulation in the environment and in food crops. Heavy metals have atomic densities higher than 4 g/cm3, and these include lead (Pb), cadmium (Cd), zinc (Zn), mercury (Hg), arsenic (As), silver (Ag), chromium (Cr), copper (Cu), iron (Fe), and platinum (Pt). The high level of environmental contamination by these metals is dangerous because their uptake by plants and subsequent accumulation in food crops consumed by humans and animals is deleterious to health. There are many known sources of harmful metals, including the earth, which releases them into food, air, and water, and anthropogenic activities, such as the application of fertilizer in agriculture, the use of pesticides and herbicides, and irrigation. Other sources are automobile emissions, paints, cigarette smoking, industries, and sewage and waste disposal. Evidence shows that vegetables and other food crops consumed in Nigeria are contaminated by heavy metals, and this is associated with adverse health issues, such as cancer, which is currently on the rise in Nigeria. It is therefore vital that communities with high levels of heavy metal pollution avoid eating large quantities of these food items. There is also the need for the monitoring of levels of these injurious elements in food crops.

Interactive Effects of Lead and Nickel Contamination on Nickel Mobility Dynamics in Spinach

Nickel (Ni) uptake pattern may be influenced in the presence of lead (Pb) metal ions in the soil and may mediate the Ni dynamics in root and shoot part of spinach. A pot culture experiment was carried out with four levels of each Pb (0, 100, 150, and 300 mg kg−1soil) and Ni (0, 100, 150, and 300 mg kg−1 soil) in spinach to assess the Pb and Ni contamination interactive effect on Ni dynamics in soil. Study revealed that increasing the concentration of Pb and Ni enhanced the concentration of the respective metals in the spinach root and shoot parts. Increasing the levels of Pb (0–300 mg kg−1) had significantly (p = 0.05) reduced the Ni uptake in shoot and root from 0.195 to 0.033 mg pot−1 and from 0.026 to 0.008 mg pot−1, respectively. The metal dynamics ratios, i.e., bioconcentration factor (BCF), translocation factor (TF), transfer efficiency (TE), and crop removal of Ni were also negatively affected by application of Pb. Increasing the Pb levels in soil from 100 to 300 mg kg−1 significantly (p = 0.05) decreases BCF value from 0.113 to 0.108. Under multi-metal toxicity conditions, high level of Pb in the effluent reduced the Ni uptake by spinach and affects the soil health. The findings are very much useful for planning effective effluent management strategies and guidelines to reduce the metal contamination in food crops under peri-urban areas.

Determination of Toxic Metals in Fruits of Abelmoschus esculentus Grown in Contaminated Soils with Different Irrigation Sources by Spectroscopic Method

Heavy metal contamination of food crops irrigated with municipal wastewater is a growing problem worldwide. In this direction, heavy metal accumulations in Abelmoschus esculentus crops were irrigated with three different water regimes (municipal wastewater, groundwater, and canal water) as well as in soil and the water sources were determined. Also, transfer factors, enrichment coefficients, pollution load indices, and health risk indices were assessed to understand the metal transportation and accumulation through the food chain. The concentrations of heavy metals in soil, water and plant samples were analysed by atomic absorption spectrophotometer equipped with a graphite furnace and D2 corrector (Perkin–Elmer Model 503). Heavy metal concentrations in the irrigation water samples ranged between 0.513–0.951 for Mo, 0.256–0.615 for As, 0.266–0.606 for Se, 41.604–54.642 for Fe, 0.285–0.753 for Cu, 0.255–0.619 for Zn, 4.684–5.212 for Ni, 3.792–5.526 for Pb, 0.035–0.065 for Cd and 2.635–4.608 for Co mg/L. The contents of Mo, As, Se, Fe, Cu, Zn, Ni, Pb, Cd and Co in soil samples ranged from 5.03 to 7.80, 34.27 to 38.96, 2.41 to 2.54, 4.77 to 5.94, 2.89 to 3.36, 1.76 to 3.63, 35.02 to 37.32, 25.10 to 28.12, 2.42 to 3.20, and 5.76 to 5.99 mg/kg, respectively, and the contents of Mo, As, Se, Fe, Cu, Zn, Ni, Pb, Cd and Co in A. esculentus samples ranged from 7.003 to 9.291, 2.800 to 3.585, 0.378 to 0.485, 39.718 to 44.048, 11.791 to 19.840, 28.203 to 37.051, 6.085 to 9.330, 4.885 to 7.061, 3.375 to 4.198, and 0.128 to 0.328 mg/kg, respectively. The range values of metal accumulation in A. esculentus samples were lower than the maximum permissible limits in plant samples except for Mo and Cd. Statistically, Se, Fe, Zn, Ni, Cd and Co concentrations did not vary significantly at all sites, while As, Mo, Cu, and Pb concentrations varied significantly in the vegetable samples.

English

China is an important global peanut producer and exporter. Nevertheless, excessive Cd in peanut kernels has become an important constraint of peanut exportation. Concerns over the heavy metal contamination in food crops have prompted scientists to find ways to solve these problems, including applications of microbiology. In the present research, a greenhouse pot culture experiment was conducted to investigate the effect of arbuscular mycorrhizal fungi (AMF) inoculation on cadmium (Cd) uptake and translocation in peanut plants at different Cd levels. The peanut seeds were sown in pots, where culture substrate was previously mixed with a given amount of Glomus intraradices and 0, 2 and 10 mg kg(-1) Cd. In the control plot, G. intraradices was inactivated before mixed into culture substrate. Symbiotic relationships were successfully established between AMF and peanut root at all Cd levels with an average colonization rate of 65.0%. Compared with control plants, AMF inoculation significantly improved phosphorus nutrition supply to peanut plants, increased chlorophyll by 7.5%, photosynthesis by 11.8%, transpiration by 13.9% and root dry weight by 27.0%. In AMF inoculated peanut plants, the concentration and accumulation of Cd were 45.9 and 87.4% higher, respectively, in root system but 31.1 and 31.8% lower, respectively in the aboveground part than in the control plants. At the Cd level of 10 mg kg(-1), the translocation rate of Cd in AMF inoculated peanut plants was 51.8% lower than in AMF non-inoculated plants. In summary, AMF inoculation could improve peanut plant growth, result in Cd immobilisation in the peanut root system and inhibit Cd translocation in peanut plants. In conclusion, AMF inoculation may be an effective way to reduce Cd accumulation in peanut kernels. (C) 2017 Friends Science Publishers

Health risk from heavy metals via consumption of food crops in the vicinity of Dabaoshan mine, South China

Heavy metal contamination of soils resulting from mining and smelting is causing major concern due to the potential risk involved. This study was designed to investigate the heavy metal (Cu, Zn, Pb and Cd) concentrations in soils and food crops and estimate the potential health risks of metals to humans via consumption of polluted food crops grown at four villages around the Dabaoshan mine, South China. The heavy metal concentrations in paddy and garden soils exceeded the maximum allowable concentrations for Chinese agricultural soil. The paddy soil at Fandong village was heavily contaminated with Cu (703 mg kg − 1 ), Zn (1100 mg kg − 1 ), Pb (386 mg kg − 1 ) and Cd (5.5 mg kg − 1 ). Rice tended to accumulated higher Cd and Pb concentration in grain parts. The concentrations of Cd, Pb and Zn in vegetables exceeded the maximum permissible concentration in China. Taro grown at the four sampled villages accumulated high concentrations of Zn, Pb and Cd. Bio-accumulation factors for heavy metals in different vegetables showed a trend in the order: Cd > Zn > Cu > Pb. Bio-accumulation factors of heavy metals were significantly higher for leafy than for non-leafy vegetable. The target hazard quotient (THQ) of rice at four sites varied from 0.66–0.89 for Cu, 0.48–0.60 for Zn, 1.43–1.99 for Pb, and 2.61–6.25 for Cd. Estimated daily intake (EDI) and THQs for Cd and Pb of rice and vegetables exceeded the FAO/WHO permissible limit. Heavy metal contamination of food crops grown around the mine posed a great health risk to the local population through consumption of rice and vegetables.