Search

A serious environmental problem that threatens soil quality, agricultural productivity, and food safety is heavy metal pollution in water sources. Heavy metal pollution is the main problem in tehsil Pasrur, Sialkot, Pakistan. Present study was arranged to notice the heavy metals in water, soil, forages and buffalo milk. There are seven sites that were used for this experiment. Highest malondialdehyde (MDA) contents (3.00 ± 0.01) were noticed in barseem roots at site 7. Ascorbate Peroxidase (APX) was reached at its peak (1.93 ± 0.01) at site 7 in the fresh barseem. Maximum protein contents (0.36 ± 0.01) were observed in fresh plant samples at site 2. Site 3's buffalo milk samples had the highest Ni content (7.22 ± 0.33 ppm), while Site 3's soil samples had the lowest Cr content (8.89 ± 0.56 ppm), Site 1's plant shoots had the lowest Cr content (27.75 ± 1.98 ppm), and Site 3's water had the highest Cr content (40.07 ± 0.49 ppm). The maximum fat content (5.38 ± 2.32%) was found in the milk of the animals at site 7. The highest density (31.88 ± 6.501%), protein content (3.64 ± 0.33%), lactose content (5.54 ± 0.320%), salt content (0.66 ± 0.1673%), and freezing point (- 0.5814 ± 0.1827 °C) were also observed in the milk from animals at site 7, whereas site 5 displayed the highest water content (0.66 ± 0.1673%) and peak pH value (11.64 ± 0.09). In selected samples, the pollution load index for Ni (which ranged from 0.01 to 1.03 mg/kg) was greater than 1. Site 7 has the highest conductivity value (5.48 ± 0.48). Values for the health risk index varied from 0.000151 to 1.00010 mg/kg, suggesting that eating tainted animal feed may pose health concerns. Significant health concerns arise from metal deposition in the food chain from soil to feed, with nickel having the highest health risk index., (© 2024. The Author(s).)

The risk assessment of trace elements has received substantial attention for the achievement of UN Sustainable Developmental Goals (UN-SDGs). The present study aimed to evaluate health and ecological risks associated with trace element accumulation in Brassica oleracea under wastewater irrigations from three different areas. This study, for the first time, compared the pros and cons of mixed water crop irrigation (wastewater with fresh/groundwater). A pot experiment was conducted to evaluate the buildup of eight trace elements (As, Cu, Cd, Mn, Fe, Pb, Ni and Zn) in soil and B. oleracea plants irrigated with wastewater alone and mixed with fresh/groundwater. Specific ecological [degree of contamination (C d ), potential ecological risk index (PERI), pollution load index (PLI), geo-accumulation index (I geo )], phytoaccumulation [bioconcentration factor (BCF) and transfer factor (TF)] and health risk models [chronic daily intake (CDI), hazard quotient (HQ), cancer risk (CR)] were applied to assess the overall contamination of trace elements in the soil-plant-human system. Moreover, these indices were compared with the literature data. The concentration of Cd, Fe and Mn exceeded the threshold limits of 10, 500 and 200 mg kg -1 , respectively, for agricultural soil. Overall, all the irrigation waters caused significant pollution load in soil indicating high ecological risk (C d  > 24, PERI > 380, Igeo > 5, PLI > 2). Not all the mixing treatments caused a reduction in trace element buildup in soil. The mixing of wastewater-1 with either groundwater or freshwater increased trace element levels in the soil as well as risk indices compared to wastewater alone. The BCF and TF values were > 1, respectively, for 66% and 7% treatments. Trace element concentration in plants and associated health risk were minimized in mixed wastewater treatments. There were 22% and 32% reduction in HQ and CR when wastewater was mixed with freshwater and 29% and 8% when mixed with groundwater. Despite total reduction, a great variation in % change in risk indices was observed with respect to the area of wastewater collection. Therefore, mixed water irrigation may be a good management strategy, but its recommendation depends on soil properties and composition of waters used for mixing. Moreover, it is recommended that the freshwater and wastewater of the particular area may be continuously monitored to avoid potential associated health hazards., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Heavy metal toxicity is becoming an increasing concern for environmental, human and animal health. The current research analyzed the lead (Pb) contamination in the food chain under three different irrigation sources (ground, canal, and wastewater). Soil, plant and animal samples were collected from the Jhang district of Pakistan and processed with an atomic absorption spectrophotometer. Lead concentration varied in the samples as: 5.22-10.73 mg/kg in soil, 2.46-10.34 mg/kg in forages and 0.736-2.45 mg/kg in animal samples. The observed lead concentration in forage and animal blood samples was higher than the standard limits. The pollution load index (0.640-1.32) in soil showed that lead contamination mainly took place at the wastewater irrigating sites. Bio-concentration factor values (0.313-1.15) were lower than one in all samples except Zea mays, showing that lead metal was actively taken up by Zea mays tissues from the soil. Enrichment factor values ranged from 0.849-3.12, showing a moderate level of lead enrichment. Daily intake and health risk index varied between 0.004-0.020 mg/kg/day and 0.906-4.99, respectively. All the samples showed maximum lead concentration at the wastewater irrigating site compared to the ground or canal water application sites. These results recommended that consistent application of wastewater for forage irrigation must be avoided to prevent health hazards associated with lead in the animal and human food chain. Government must implement adequate strategies to protect the animal and human health from the harms of toxic heavy metals.

Irrigation using sewage water can be beneficial, as it can increase the productivity of crops but has negative consequences on crops, soil contamination, and human health. It contains a variety of toxins, such as chemicals and heavy metals, which damage the soil and crops. In this regard, the aim of the research was to assess the potential health hazards of iron (Fe) metal in food crops (leafy and root crops) treated with wastewater (T_1), canal water (T_2), and tube well water (T_3). Water, soil, and edible components of food crops were collected at random from three distinct locations. Fe concentration in samples was estimated using atomic absorption spectrophotometer, following wet digestion method. The Fe concentrations, ranged from 0.408 to 1.03 mg/l in water, 31.55 to 187.47 mgkg-1 in soil and 4.09 to 32.583 mgkg-1 in crop samples; which were within permissible limits of the World Health Organization (WHO). There was a positive correlation between soils and crops. The bioconcentration factor, enrichment factor (EF), daily intake of metals (DIM), health risk index (HRI), and target hazard quotient (THQ) all values were <1, except for a pollution load index >1, which indicated soil contamination, but there was no Fe toxicity in crops, no health risk, and no-carcinogenic risk for these food crops in humans. To prevent the excessive accumulation of Fe metal in the food chain, regular monitoring is needed., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Akhtar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Present study was conducted to check the heavy metal content in wheat treated with municipal solid waste, Although municipal solid waste was enriched with organic nutrient, micronutrients, and macro-nutrients, considerable amount of cobalt was also witnessed in municipal solid waste that s why pot experiment was executed. The concentration of cobalt in different parts of wheat (root, shoot, and grain) was analyzed by atomic absorption spectrophotometer (AA-6300 Shimadzu Japan). Highest concentration of cobalt in root, shoot, and grain of wheat was observed in the range of 0.91-1.02 mg/kg, 0.92-1.04 mg/kg, and 0.93-1.00 mg/kg, respectively, under the influence of different fertilizer's used, while in field experiment, level of Co was greater in roots followed by shoots and grain. The metal concentration in wheat grown in field was ranged from 0.67 to 0.72 mg/kg for roots, 0.64 to 0.71 mg/kg for shoots, and 0.66 to 1.71 mg/kg for grains. Concentrations of cobalt were found below the permissible limits suggested by FAO/WHO. Various indices (PLI, BCF, DIM, HRI) were calculated and results showed that PLI was above 1 indicating that metal was causing pollution in treatments while value of BCF, DIM, and HRI was within the permissible range. Higher Co content in wheat may cause damage to the pancreatic cells of animals, cause respiratory problems, and effects their kidney, liver, and lungs, if exposure is for long period through feed., (© 2022. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

In District Jhang, farmers use municipal wastewater to irrigate fodder crops as an alternative source to the deficient availability of fresh water. Therefore, the present study selected the three irrigation sources in District Jhang (canal water, ground water and municipal wastewater) to study the iron (Fe) concentration in the soil, fodder crops and ultimately their transfer into the animal body. Analysed Fe concentration varied as 16.40-27.53 mg/kg in soil samples, 19.72-30.34 mg/kg in fodder crops and 2.49-5.11 mg/kg in animals. Analysed Fe concentration in soil was higher on the wastewater irrigation site while canal water-irrigated fodder crop Zea mays exhibit the higher Fe concentration. In animal samples, higher Fe concentration was observed in the cow blood (4.09 mg/l), cow hairs (3.39 mg/kg) and cow faeces (5.11 mg/kg). Results of pollution load index (0.288-0.484 mg/kg) and enrichment factor (0.112-0.197 mg/kg) indicated that Fe concentration was minimally dispersed and enriched in these sites. Health risk and daily intake values were observed between the 0.029-0.059 and 0.042-0.084 mg/kg/day. Bio-concentration factor (0.834-1.47 mg/kg) for Fe which was greater than 1 explains that Fe contamination was transferred from the soil to fodder tissues and may raise health issues in the grazing animals if they are continuously exposed to these contaminated forages. Wastewater irrigation in study area has increased the Fe content in soil-plant environment that is a risking factor for animal and human health. Hence, this study recommended that wastewater should be treated prior to their irrigation on agricultural lands., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Many studies have described the physiological, biochemical, and molecular responses to heavy metal toxicity and deficiencies individually in plants. The present study assess nickel (Ni) concentration in amended soil, plant vegetative parts, and wheat grains, grown under diverse types of fertilizers in Sargodha, Punjab, Pakistan. Different varieties of wheat were grown in pot and fields. Different treatments (municipal solid waste, poultry waste, press mud, farm yard manure) of fertilizers were applied in order to study the metal level increased in different parts (root, shoot, grain) of wheat due to fertilization. Results indicated that metal level was found highest in roots followed by shoot and grain. The highest level of nickel in root was present in V1 (2.35 mg/kg) due to T2 (2.60 mg/kg) treatment. Higher nickel levels in wheat shoot and grains were observed in V5 (2.36 mg/kg) and V8 (2.29 mg/kg), respectively, due to applied treatment T2 (2.57 mg/kg). This study concluded that treatment T9 was proven safe in view of the observed Ni concentration, while treatment T2 (municipal solid waste) resulted in higher accumulation of nickel in wheat grains which showed that municipal solid waste should be treated before their application in agriculture fields to secure the public health. This study recommended that although application of fertilizers increased the plant growth and nutritional value, it also enhanced metal accumulation in the wheat grains which could be harmful for consumers especially human being. Government should take actions to prevent metal toxicity in human food chain., (© 2021. Crown.)

Heavy metal pollution in soil, forage, and animals is serious concern nowadays. Current research was conducted in Sargodha to find out the relationship of animals related to the forages and soil pollution. Three sites were selected with three different treatments; site I irrigated with ground water, site II irrigated with the canal water, and site III irrigated with the wastewater. Samples of soil, forage, and animals (blood, hair, feces) were collected from selected sites and were analyzed for metal analysis using atomic absorption spectroscopy. Results indicated that Zn in soil ranged from 24.12 to 37.39 mg/kg; forage, 31.98-44.47 mg/kg; blood of animals, 1.49-2.72 mg/L; hair of animals, 1.37-2.41 mg/kg; and feces of animals, 1.06-2.97 mg/kg. The concentration of zinc in soil and forage was less than permissible limit, but concentration in blood of animals was greater than critical limit suggesting the presence of metal. Bio-concentration factor indicated that metal was accumulated in forages growing at irrigated site. HRI concentration (2.024 mg/kg/day) suggests the accumulation of zinc in animal tissues. Pollution load index and enrichment factor were within the range., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

This study's aim was to investigate iron (Fe) and zinc (Zn) concentration in the soil, forage crops, and sheep blood with respect to the seasonal availability of these metals. Soil, forage, and sheep blood samples were sampled from five different locations in Chakwal (Pidh, Tobar, Ratoccha, Choa Saiden Shah-Kalar Kahar road, and Choa Saiden Shan-Chakwal Road) during two seasons, i.e., winter and summer. All the samples were processed through wet acid digestion for evaluation of metal contents. Because of proximity of site-1 and site-2 to coal mines, higher Fe concentration was observed than Zn. Overall, varied Fe concentrations obtained in soil were 12.95-24.31 mg/kg, 1.29-9.61 mg/kg in forage and 1.17-24 mg/l in blood, whereas Zn values were 1.04-31.9 mg/kg, 1.96-7.02 mg/kg, and 0.16-6.52 mg/l for soil, forages, and blood respectively. The pollution load index value for both Fe (0.01-0.14 mg/kg) and Zn (0.02-0.72 mg/kg) was lesser than 1. Bio-concentration (0.09-2.64mg/kg) and enrichment factor (0.08-7.51 mg/kg) were showing efficient transfer of metals through the food chain. Daily intake and health risk index values of iron were ranged from 0.01 to 1.1 mg/kg/day and 0.02 to 1.05 mg/kg/day. There was a probable chance of upsurge in metal values in coming years due to continued mining activities. Anthropogenic input, mainly mining activities in the study area, have increased the Fe and Zn content in the environment which can ultimately find their way up the food chain, thereby risking the health of grazing livestock., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

Heavy metals pollution has thorough worldwide apprehensions due to the instantaneous growth of industries. Farming regions are irrigated mainly with wastewater which contains both municipal and industrial emancipations. Keeping in view the above scenario, a study was designed in which three sites irrigated with ground, canal, and municipal wastewater in the District Jhang were selected to determine the zinc accumulation and its transfer in the soil, plant, and animal food chain. Zinc concentration was ranged as 18.85-35.59mg/kg in the soil, 26.42-42.67 mg/kg in the forage, and 0.982-2.85mg/kg in the animal samples. Investigated zinc concentration in soil and forages was found to be within the recommended WHO/FAO limits, but blood samples exceed the standards of NRC (2007). The maximum level of pollution load index (0.427-0.805mg/kg) and enrichment factor (0.373-0.894 mg/kg) for zinc was noticed upon wastewater irrigation. Daily intake (0.039 to 0.082 mg/kg/day) and health risk index (0.130 to 0.275 mg/kg/day) of zinc metal was higher in the buffaloes that feed on wastewater-irrigated forages. Bio-concentration factor (0.840 to 2.01mg/kg) for soil-forage was >1 which represents that these plants accumulated the zinc concentration into their tissues and raised health issues in grazing animals on consumption of wastewater-contaminated forages. As animal-derived products are part of human food, then zinc toxicity prevailed in livestock tissues ultimately affects the human food chain. Overall, findings of this study concluded that animal herds should be monitored periodically to devise preventive measures regarding the toxic level of heavy metals availability to livestock., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

Grazing animals act as a bioindicator to study the heavy metal status in the pasture lands because excessive amount of toxic metals in the animal diet either disturb their normal activity or deposit the contaminants into their tissues. The aim of this study was to appraise the chromium status in soil and pasture crops with respect to the nutritional requirement of grazing animals. Three different sites were selected to collect soil, forages, and animal samples from District Jhang. All the samples were processed through atomic absorption spectrophotometer to analyze the chromium concentration in them. Chromium concentration was varied as 0.703-4.20 mg/kg in soil, 0.45-2.85 mg/kg in forages, and 0.588-2.37 mg/kg in all collected animal samples. Both the soil and forage samples displayed the maximum chromium concentration in the Capparis decidua, whereas animal samples revealed maximum concentration in animal blood. Results of pollution load index (0.078 to 0.463 mg/kg) exhibited that all the sample values are less than unity while enrichment factor (1.57-8.25mg/kg) showed that significant level of chromium is enriched in these sites. The maximum value of daily intake (0.0007-0.0055mg/kg/day) and health risk index (0.0004-0.00370055mg/kg/day) was observed in the buffalo that feed on the Capparis decidua. Bio-concentration factor (0.398-2.09mg/kg) value was the maximum in the Medicago sativa. It is concluded that all the animal samples showed chromium concentration beyond their standards. Thus, proper measures should be taken to reduce the metal contamination in these areas that ultimately lessen the availability of toxic metals to grazing animals., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

Present work evaluated the zinc (Zn) concentration in soil, forage, blood plasma, hair, and feces samples of cows, buffaloes, and sheep taken from Mianwali, Punjab, Pakistan. The concentration of Zn was found in the ranged of 21.82-35.09mg/kg, 32.59-42.17mg/kg, 0.927-2.48mg/l, 1.03-2.84mg/kg, and 0.923-1.98mg/kg in soil, forage, blood plasma, hair, and feces samples, respectively. The Zn concentration in soil, forage, blood, hair, and feces was safer compared to standard limits. Statistical analysis described that values for BCF, PLI, EF, DIM, and HRI ranged 1.03-1.57mg/kg, 0.486-0.782mg/kg, 0.457-0.696mg/kg, 0.048-0.08mg/kg, and 0.160-0.272mg/kg, respectively. It can be concluded from the present work that Zn concentration was safe in soil, forages, and animal samples. BCF was noticed as greater than 1 while PLI, EF, DIM, and HRI were found less than 1, so regular heavy metal analysis was required to appraise the contamination level in environment., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

The aim of this study was to access the Mn contamination in soil, forages, and animals. Heavy metal pollution is a matter of prime significance in natural environment. Through food chain, toxicity of heavy metals and their bioaccumulation potential are transferred into humans. Higher concentrations of metallic compounds are toxic to living organisms but these are essential to maintain body metabolism. Intake of food crops polluted with heavy metals is chief food chain channel for human exposure. Animals are exposed to heavy metal stress by the intake of richly contaminated food crops; those are chief part of food chain. Samples of soil, plant, animal blood, hair, and feces were collected to find contamination through wet digestion process in lab and metal analysis. Different forages were collected to study Mn content that was our major concern in this study. The present findings also emphasized on the assessment of bio-concentration factor (BCF). Other significant indices of mobility and pollution of metal were also calculated, i.e. pollution load index (PLI), daily intake of metal (DIM), health risk index (HRI), and enrichment factor (EF). The experimentation result showed different concentrations of metal in different seasons. The Mn concentration in forages was 20.01-28.29 mg/kg and in soil was 5.27-8.90 mg/kg. Soil samples showed higher level of (PLI) Pollution load index. Bio-concentration of MN was 2.59-4.21 mg/kg. It can be concluded that regular monitoring of the metal is essential to evaluate the contamination status. Mn contents were in the safe limits in soil and plants; however, its toxic level was observed in animals., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

The instant endeavor was undertaken for determination of lead (Pb) in water, soil, forage, and cow's blood domesticated in contaminated area of heavy automobiles' exhaust in Sahiwal town of District Sargodha, Pakistan. Water samples showed that the concentration of Pb ranged from 1.14 to 0.44 mg kg -1 at all sites. It was maximum at site 5 and minimum at site 2. Soil samples showed the concentration of Pb at all sites ranged from 1.58 to 0.279 mg kg -1 . It was maximum in soil where Avena sativa was grown at site 5 and was found minimum in soil where Zea mays was grown at site 2. While among samples of forage, the concentration of Pb ranges from 0.048 to 2.002 mg kg -1 . The highest Pb amount was found in Brassica campestris at site 1 and the minimum was recorded in Trifolium alexandrinum at site 2. Finally, the blood samples of cow depicted that concentration of Pb ranged from 4.468 to 0.217 mg kg -1 . It was the maximum at site 1 and the minimum at site 3. It is recommended that such study should be conducted in other districts for public awareness., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The instant endeavor was undertaken to monitor copper (Cu) contents in water, soil, forage, and cow's blood impacted by heavy automobiles in Sahiwal town of district Sargodha, Pakistan. The samples were collected in triplicates with a total of 120 soil and water samples with corresponding forage samples. For the analysis of metal concentration in cows, 60 blood samples were collected from the cows feeding on these forages on selected sites. Metal contents were analyzed by atomic absorption spectrophotometry. The results showed that water samples contained mean values of Cu concentration ranged from 1.01 to 0.444 mg/kg at all sites. It was maximum at site 3 and minimum at site 6. The soil samples of all the forage fields showed Cu mean values concentration ranged from 1.94 to 0.286 mg/kg at all sites. It was maximum in Trifolium alexandrinum grown field at site 2, and minimum in Avena sativa at site 2. All the forage samples showed the mean value of Cu concentration ranged from 0.151 to 1.86 mg/kg at all sites. The concentration of Cu was maximum in Zea mays grown at site 5 and minimum in Trifolium alexandrinum at site 4. The cow blood samples showed the mean concentration of Cu ranged from 1.368 to 0.53 mg/kg at all sites. It was maximum at site 2 and minimum at site 6. Owing to the results of pollution index and transfer factors, metal content was found to be in permissible range in forages as well as animal samples.

The use of wastewater in irrigation weakens the beneficial properties of the soil and leads to a threat to food safety standards. The present research was designed to explore the cobalt toxicity associated with the ingestion of wastewater irrigated wheat. Wheat plants of five different varieties were collected from 7 different sites of Punjab, Pakistan, which were irrigated with three different sources of water. The sampling was done in two cropping years. The cobalt values in water, soil and wheat samples (root, shoot, grain) ranged from 0.46 to 1.24 mg/l, 0.15 to 1.20, 0.29 to 1.30, 0.08 to 0.76 and 0.12 to 0.57 mg/kg, respectively. All the water samples showed high cobalt concentration than the maximum permissible value. However, all the soil and wheat plant samples were found within the maximum allowable range. The high cobalt concentration in irrigating water showed that the continuous usage of such type of water may lead to cobalt toxicity in living organisms with the passage of time and may results in severe health risks.

The study was carried out to evaluate the health risks associated with accumulation of cadmium in the different genotypes of wheat, grown in agricultural regions of Punjab, Pakistan. Five genotypes irrigated with three varied water sources were selected randomly from each region. Among all sources of water, types of soil, and grain samples, the cadmium (Cd) quantities were found (2.24-2.82 mg/L, 1.75-4.16 mg/kg, 0.86-1.90, respectively), exceeding the maximum permissible limits (0.01 mg/L, 1.1 mg/kg, 0.2 mg/kg, respectively) described by FAO/WHO. The pollution load index (PLI) exhibited by all of the samples was higher than 1.00, the permissible limit; however, other factors including bioaccumulation, translocation, bio-concentration, daily intake, and enrichment values of Cd were less than 1.00. Moreover, the health risk index for cadmium in all types of wheat grain samples was less than 1.00. The study concluded that the continuous use of wastewater resources may lead to the accumulation of cadmium in the vital body organs that may cause severe health hazards.

The accumulation of heavy metals by crops irrigated with wastewater has been considered as a serious environmental problem in many developing countries, where the wastewater irrigation has emerged as a common practice. In this research, we were concerned with the highly toxic metal lead (Pb) in water, agricultural soils, and wheat crops, and the possible risk on human health in the peripheral agricultural regions of Punjab, Pakistan. Various types of irrigated water (ground, sewage, industrial), soil, and wheat plant (root, shoot, grain) samples of five different varieties (Seher-2006, Punjab-2011, Faislabad-2008, Watan, and Galaxy-2013) were collected from seven different districts and then pooled up to make one composite sample and analyzed for Cd concentration. The various pollution and mobility indices (pollution load index, enrichment factor, daily intake of metal, health risk index, translocation factor, bioaccumulation factor, and bio-concentration factor) were also calculated. The descending order for Pb concentration was as follows: water>soil>wheat plant. The range of concentration of Pb in all types of water, soil, and wheat plant (root, shoot, grains) samples was (7.05-7.83 mg/l), (6.32-7.74 mg/kg), (3.23-4.82, 1.14-2.75, 0.09-0.51 mg/kg), respectively. The concentration of Pb in all types of water samples exceeded the maximum permissible limit. There were values found to be < 1.00 in all the pollution and mobility indices for all types of samples. These results reveal that high levels of Pb in irrigated water may pollute the soil and wheat plants of these regions in the near future, if various control measures have not been taken. It may pose a great health risk to the local human and animal populations. Preventive measures should be taken to reduce heavy metal pollution of irrigation water and soils to protect both human and animal health in various regions of Punjab, Pakistan.

Mineral fertilizers and organic manure are used as soil amender to enhance the mineral status of the soil. These fertilizers contain trace metals besides providing macro and micronutrients. The present study was performed to observe the effect of mineral fertilizers, poultry manure and cow manure on trace metal content of soil and various parts (root, shoot, and grains) of maize plant (Zea mays L.). The analysis of metals was performed by atomic absorption spectrophotometer (AA-6300 Shimadzu Japan). The highest level of Pb, Fe, Ni and Cu was observed in the root as 0.36-0.55, 70.41-83.03, 4.98-7.44 and 2.94-4.43 mg kg - 1 , respectively. The highest level of Cd, Zn and Mn was determined in grains as 0.44-1.59, 28.05-46.39 and 26.24-46.57 mg kg - 1 , respectively. The values of all metals were found within their permissible limit given by FAO/WHO except for the Cd. The interactive use of mineral and organic fertilizers enhanced the level of trace metals in maize as compared to their sole application. In the present findings, the health risk index for all metals was less than 1 in all treatments. So, it was concluded that the level of metals in poultry manure, cow manure and mineral fertilizer treated maize did not pose any potential threat to the consumers.

Accretion of heavy metals in forage is a potential risk to grazing animals due to their uptake by plants and its entrance into the food chain. This study aimed to examine the Mn and Cd concentration from different samples. Sampling was done twice after the interval of 6 months during 2018; five different sites from Chakwal (Pidh, Tobar, Ratoccha, Kalar Kahar Road, Choa Saiden Shah and Chakwal Road, Choa Saiden Shah) were selected. Thirty samples of soil, forage (Acacia nilotica, Ziziphus nummularia, and Acacia modesta), and blood were collected. Forage and soil samples were dried, ground very fine, digested by wet digestion method, and analyzed by atomic absorption spectrophotometer. Samples collected from site I and site II had a very high concentration of heavy metals because these sites were very close to the coal mines and receive higher contamination. Manganese concentration in the soil fluctuated from 5.46 to 1.20, in the forage 6.84 to 1.00, and in the blood 5.21 to 1.03 mg/l, and cadmium concentration in the soil fluctuate from 1.85 to 0.03, in the forage 0.57 to 0.16, and in the blood 1.67 to 0.25 mg/l. Manganese concentration was higher as compared to the Cd. Higher concentration of Mn shows that this metal is due to human activities. Pollution load index value of Cd was higher than 1 in some samples, and the value fluctuates from 0.01 to 1.24 mg/kg. The values of a bioconcentration factor for Mn were greater than 1. Daily intake of metal value fluctuates from 0.01 to 1.03 mg/kg. Health risk index value ranges from 0.03 to 1.09 mg/kg. Health risk index of metals showed the risk which is due to the intake of contaminated fodder. From the soil, the metals can enter forage and bioaccumulate in the food chain. The health risk index was highest for Cd. The result obtained from the present research work indicated that there is a biomagnification of both metals in the food chain due to mining activities.

The cheapest way of disposal of wastewater is its use in agriculture. The pressure in using fresh water resources may be alleviated by the domestic wastewater in agriculture. Wastewater holds significant quantity of plant nutrients like N, P, Ca, K, Co, Zn, and Mn. Therefore, it increases the crop yield. Triticum aestivum is the staple food crop for Pakistan, where it is an important caloric source. It is grown successfully in rain fed areas of the country as well as in irrigated areas with minimum water without losing its production potential. In this study, cadmium (Cd), nickel (Ni), iron (Fe), manganese (Mn), copper (Cu), chromium (Cr), zinc (Zn), and cobalt (Co) were evaluated; the effect of wastewater was studied on wheat variety (Punjab-2011) by applying different treatments of wastewater. In the comparison between five different treatments, in soil, Fe was the highest. The chromium in the current findings exceeded the permissible limit (0.03 mg/kg) in wheat grains. The reason of high Cr concentration might be due to the increased usage of wastewater for long periods. The level of pollution or the factor of contamination was the lowest for Zn and was highest for Cd in all treatments. Chromium has the lowest value of health risk index while Cd has the highest value in all treatments, indicating that exposed population is unlikely to experience obvious adverse effects on utilization of these contaminated grains of wheat.

As a result of the industrial revolution, anthropogenic activities have enhanced there distribution of many toxic heavy metals from the earth's crust to different environmental compartments. Environmental pollution by toxic heavy metals is increasing worldwide, and poses a rising threat to both the environment and to human health.Plants are exposed to heavy metals from various sources: mining and refining of ores, fertilizer and pesticide applications, battery chemicals, disposal of solid wastes(including sewage sludge), irrigation with wastewater, vehicular exhaust emissions and adjacent industrial activity.Heavy metals induce various morphological, physiological, and biochemical dysfunctions in plants, either directly or indirectly, and cause various damaging effects. The most frequently documented and earliest consequence of heavy metal toxicity in plants cells is the overproduction of ROS. Unlike redox-active metals such as iron and copper, heavy metals (e.g, Pb, Cd, Ni, AI, Mn and Zn) cannot generate ROS directly by participating in biological redox reactions such as Haber Weiss/Fenton reactions. However, these metals induce ROS generation via different indirect mechanisms, such as stimulating the activity of NADPH oxidases, displacing essential cations from specific binding sites of enzymes and inhibiting enzymatic activities from their affinity for -SH groups on the enzyme.Under normal conditions, ROS play several essential roles in regulating the expression of different genes. Reactive oxygen species control numerous processes like the cell cycle, plant growth, abiotic stress responses, systemic signalling, programmed cell death, pathogen defence and development. Enhanced generation of these species from heavy metal toxicity deteriorates the intrinsic antioxidant defense system of cells, and causes oxidative stress. Cells with oxidative stress display various chemical,biological and physiological toxic symptoms as a result of the interaction between ROS and biomolecules. Heavy-metal-induced ROS cause lipid peroxidation, membrane dismantling and damage to DNA, protein and carbohydrates. Plants have very well-organized defense systems, consisting of enzymatic and non-enzymatic antioxidation processes. The primary defense mechanism for heavy metal detoxification is the reduced absorption of these metals into plants or their sequestration in root cells.Secondary heavy metal tolerance mechanisms include activation of antioxidant enzymes and the binding of heavy metals by phytochelatins, glutathione and amino acids. These defense systems work in combination to manage the cascades of oxidative stress and to defend plant cells from the toxic effects of ROS.In this review, we summarized the biochemiCal processes involved in the over production of ROS as an aftermath to heavy metal exposure. We also described the ROS scavenging process that is associated with the antioxidant defense machinery.Despite considerable progress in understanding the biochemistry of ROS overproduction and scavenging, we still lack in-depth studies on the parameters associated with heavy metal exclusion and tolerance capacity of plants. For example, data about the role of glutathione-glutaredoxin-thioredoxin system in ROS detoxification in plant cells are scarce. Moreover, how ROS mediate glutathionylation (redox signalling)is still not completely understood. Similarly, induction of glutathione and phytochelatins under oxidative stress is very well reported, but it is still unexplained that some studied compounds are not involved in the detoxification mechanisms. Moreover,although the role of metal transporters and gene expression is well established for a few metals and plants, much more research is needed. Eventually, when results for more metals and plants are available, the mechanism of the biochemical and genetic basis of heavy metal detoxification in plants will be better understood. Moreover, by using recently developed genetic and biotechnological tools it may be possible to produce plants that have traits desirable for imparting heavy metal tolerance.

Rawal Lake Reservoir is renowned for its ecological significance and is the sole source of drinking water of the third largest city of Pakistan. However, fish kill in recent years and anthropogenic impacts from human-related activities in its catchment area have resulted in deterioration of its surface water quality. This study aims to characterize spatial and temporal variations in surface water quality, identify contaminant sources, and compare their levels with quality guidelines. Surface water samples were collected from 10 sites and analyzed for 27 physicochemical parameters for a period of 2 years on a seasonal basis. Concentration of metals in surface water in pre-monsoon were in the order: Fe > Mg > Ca > Mn > Zn > Ni > Cr > Cu > Co > Pb, whereas in post-monsoon, the order of elemental concentrations was: Ca > Mg > Na > Fe > K > Zn > Cr > Li > Pb > Co > Ni > Cu > Mn > Cd. Metals (Ni, Fe, Zn, and Ca), pH, electrical conductivity (EC), dissolved oxygen (DO), chemical oxygen demand (COD), and nutrients (PO (4) (3-) , NO(3)-N, and SO (4) (2-) ) were measured higher in pre-monsoon, whereas concentration of Cu, Mn, Cr, Co, Pb, Cd, K, Na, Mg, Li, Cl(-), and NH(4)-N were recorded higher in post-monsoon. Results highlighted serious metal pollution of surface water. Mean concentration of Zn, Cd, Ni, Cu, Fe, Cr, and Pb in both seasons and Mn in post-monsoon were well above the permissible level of surface water quality criteria. Results stress the dire need to reduce heavy-metal input into the lake basin and suggest that heavy-metal contamination should be considered as an integral part of future planning and management strategies for restoration of water quality of the lake reservoir.