Heavy metals (As, Cr, Pb, Cd and Ni) concentrations in rice (Oryza sativa) from Iran and associated risk assessment: a systematic review

Elucidating the Environmental and Health Risks of Trace Element Pollution in Red Sea Fish from Nuweiba City, Aqaba Gulf, Egypt

Trace element bioaccumulation in marine organisms is a rising international issue due to possible health concerns for humans. Thirteen trace elements were analyzed in the sediment, water, and muscular tissue of Red Sea fish. Additionally, the average daily intake (EDI), the cancer risk (CR), the hazard index (HI), and the target hazard quotient (THQ) of those elements have been taken into consideration when evaluating any possible health concerns related to their consumption. All species presented quantifiable values in muscle for all the analyzed elements (arsenic (As), lead (Pb), copper (Cu), aluminum (Al), boron (B), iron (Fe), barium (Ba), manganese (Mn), nickel (Ni), cadmium (Cd), chromium (Cr), zinc (Zn), and mercury (Hg), except for Cd and Hg, being Fe and Zn the most accumulated elements in all species. Conversely, in water samples, most elements were undeleted except for aluminum, boron, iron, and zinc. All Red Sea fish, however, had concentrations of Zn, Ni, Fe, Cu, and Mn below the upper limit allowed, although most species had higher levels of As, Cr, and Pb (0.48 ± 0.83-5.10 ± 0.79, 1.97 ± 0.46-5.25 ± 0.67 and 2.12 ± 1.01-6.83 ± 0.93 µg/g, respectively).The studied Red Sea fish showed contamination degrees (CD) of Mn, Cu, Fe, Ni, Zn, and Pb were ≤ 1, indicating minimal contamination, with As and Cr showing higher contamination degrees. However, the pollution index values (MPI-elements) can be represented according to ascending order: Lethrinus ramak < Cephalopholis hemistiktos < Pagellus affinis < Trachurus japonicus < Cheilinus lunulatus < Siganus luridus < Parupeneus forsskali < Caesio suevica. The study found that edible tissues are safe for human consumption, with HI values for children and adults less than ten, indicating negligible non-cancer hazards. However, fish consumption presents health risks due to chromium, lead, and arsenic, with THQ values several times greater than 1, and CR-Ni, CR-Cr, and CR-As values exceeding the acceptable 10-4 value in all studied species. This study provides critical insights into trace element contamination in marine fish species, highlighting the need for ongoing monitoring and proactive measures to ensure safe marine fish consumption in the Aqaba Gulf.

Evaluation of carcinogenic risk of heavy metals due to consumption of rice in Southwestern Iran

Pollution by heavy metals is a serious global problem due to its toxicity, abiotic characteristics, abundant sources, and cumulative behavior. On the other hand, considering the importance of rice consumption as an important part of nutrition in Lordegan and Ahvaz cities, this study was conducted to evaluate the carcinogenic risk of heavy metals lead, cadmium, zinc, nickel and in local Champa rice cultivated in these two cities. 16 Champa rice samples were collected from the fields of Lordegan and Ahvaz cities. The elements were read in three replicates by Varian 710-ES atomic emission device. The results showed that the concentration of cadmium and nickel in the cultivated rice in the two studied cities was within the range of the national standard of Iran and the Codex standard. Carcinogenic risk values for lead, cadmium and nickel in Champa Lordegan and Ahvaz rice were within the safe range. Also, the non-carcinogenic risk for these heavy metals in the two studied areas was less than 1 and was in the safe range. Rice pollution in Champa in Ahvaz can be due to the industrial nature of this city, and in Lordegan, it is due to pollution through pesticides, chemical fertilizers, and transportation. Long-term consumption of contaminated rice may endanger the health of residents of these areas. It is recommended to carry out regular and up-to-date monitoring strategies in these two cities to prevent the entry of these toxic heavy metals into the human food chain. Also, more studies are needed to evaluate the complete scenario and make definitive decisions.

Anthropogenic-induced environmental and ecological changes in the Nile Delta over the past half-century

Anthropogenic activities over the past half-century have had a negative impact on the wetland ecosystem in the Nile Delta, which provides essential provisioning and regulating services. Therefore, it is crucial to systematically investigate pollution levels and their ecological consequences at both spatial and temporal scales in order to promote sustainable development. In this study, data on metal pollution in the Manzala Lake were compiled through a systematic review of all published literature from 1968 to 2020. Additionally, agricultural data (including land use, pesticide and fertilizer usage, and discharge) and economic data for the same time period were collected to identify the main drivers of pollution. The results indicated an overall increasing trend in heavy metal concentrations during the study period. The average concentrations of metals, arranged in descending order, were as follows: Fe (15,115.5 μg/g) > Mn (722 μg/g) > Zn (115.4 μg/g) > Cu (65.9 μg/g) > Ni (62.5 μg/g) > Cr (58.1 μg/g) > Pb (54.1 μg/g) > Cd (4.7 μg/g) > Hg (0.1 μg/g). A linear regression model revealed that wastewater discharge, water reuse, and the use of pesticides and fertilizers are the main sources of heavy metal pollution in the Manzala Lake. Consequently, there has been a dramatic decrease in the biodiversity of fish and molluscan communities. The study also found a correlation between heavy metal pollution and socio-economic development, highlighting the urgent need for attention to the conservation, management, and sustainable development of the lake.

The association between toxic metals (As, Pb and Cd) exposure and rice cooking methods: A systematic review and meta-analysis

Heavy metal exposure through rice consumption (Oryza sativa L.) is a human health concern. This systematic review and meta-analysis investigated the association between toxic metals exposure and rice cooking methods. Based on the inclusion and exclusion criteria, fifteen studies were selected as eligible for the meta-analysis. Our results showed a significant decrease in the content of arsenic, lead, and cadmium following the cooking rice (WMD= -0.04 mg/kg, 95% CI: -0.05, -0.03, P = 0.000), (WMD = -0.01 mg/kg, 95% CI: -0.01, -0.01, P = 0.000), and (WMD = -0.01 mg/kg, 95% CI: -0.01, -0.00, P = 0.000), respectively. Furthermore, based on the subgroup analysis the overall rank order of cooking methods in the rice was rinsed > parboiling > Kateh > high-pressure, microwave, and steaming. The findings of this meta-analysis indicate the beneficial effects of cooking on reducing arsenic, lead, and cadmium exposure via rice consumption.

The concentration of radioisotopes (Potassium-40, Polonium-210, Radium-226, and Thorium-230) in fillet tissue carp fishes: A systematic review and probabilistic exposure assessment

Chemical contamination of seafood has become a global health concern. Carp fish is one of the most widely consumed globally, and several studies have been conducted on the contamination of carp fish with radioisotopes. In the current study, a meta-analysis and probabilistic exposure assessment regarding the Potassium-40 (40K), Polonium-210 (210Po), Radium-226 (226Ra), and Thorium-230 (230Th) in the fillet tissue of carp fish were performed. In this regard, Scopus and PubMed were screened to retrieve the associated citations with on the concentration of radioisotopes in the fillet tissue of carp fish until October 2021. The rank order of radioisotopes in fillet tissue carp fish was 40K (103.49 Bq kg-1) > 210Po (9.39 Bq kg-1) > 226Ra (0.62 Bq kg-1) > 230Th (0.39 Bq kg-1). The highest effective dose due to 210Po ingestion was observed in Spain (male; 4.44E-05 Sv y-1, female; 2.67E-06 Sv y-1); 40K (female, 5.07E-07 Sv y-1); 226Ra (male, 9.93E-09 Sv y-1). The mean of effective dose (ED) in the male and females in India due to ingestion of 230Th as result of carp fish consumption was (1.70E-06 Sv y-1) and (7.01E-08 Sv y-1), respectively. The probabilistic exposure assessment by the Monte Carlo simulation method revealed that consumers of fillet tissue carp fish content of radioisotopes are at a safe range (0.001 Sv y-1).

Bioaccumulation and sources of metal(loid)s in fish species from a subtropical river in Bangladesh: a public health concern

Toxic metals and freshwater fish's metalloid contamination are significant environmental concerns for overall public health. However, the bioaccumulation and sources of metal(loids) in freshwater fishes from Bangladesh still remain unknown. Thus, the As, Pb, Cd, and Cr concentrations in various freshwater fish species from the Rupsha River basin were measured, including Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Mystus vittatus, Glossogobius giuris, and Pseudeutropius atherinoides. An atomic absorption spectrophotometer was used to determine metal concentrations. The mean concentrations of metal(loids) in the fish muscle (mg/kg) were found to be As (1.53) > Pb (1.25) > Cr (0.51) > Cd (0.39) in summer and As (1.72) > Pb (1.51) > Cr (0.65) > Cd (0.49) in winter. The analyzed fish species had considerably different metal(loid) concentrations with seasonal variation, and the distribution of the metals (loids) was consistent with the normal distribution. The demersal species, M. vittatus, displayed the highest bio-accumulative value over the summer. However, in both seasons, none of the species were bio-accumulative. According to multivariate statistical findings, the research area's potential sources of metal(loid) were anthropogenic activities linked to geogenic processes. Estimated daily intake, target hazard quotient (THQ), and carcinogenic risk (CR) were used to assess the influence of the risk on human health. The consumers' THQs values were < 1, indicating that there were no non-carcinogenic concerns for local consumers. Both categories of customers had CRs that fell below the permissible range of 1E - 6 to 1E - 4, meaning they were not at any increased risk of developing cancer. The children's group was more vulnerable to both carcinogenic and non-carcinogenic hazards. Therefore, the entry of metal(loids) must be regulated, and appropriate laws must be used by policymakers.

Heavy Metals Assessment and Health Risk to Consumers of Two Commercial Fish Species from Polyculture Fishponds in El-Sharkia and Kafr El-Sheikh, Egypt: Physiological and Biochemical Study

Metal pollution is a major environmental concern worldwide, especially in Egypt. The aquaculture industry uses widespread artificial feeds to stimulate fish production, leading to metal accumulation in the aquatic environment. Heavy metal concentrations (HMCs) in sediments, water, and tissues were studied to study the effect of pollution levels on heamatological, and biochemical, immunological aspects of farmed fish as well as on human health. Results declared that the HMC levels in the water and sediment were significantly different between El-Sharkia and Kafr El-Sheikh fishponds (T-test, p < 0.05). This was supported by the metal pollution index in the water and sediment, indicating that El-Sharkia fishponds (ES fishponds) were more contaminated than Kafr El-Sheikh fishponds (KES fishponds). Also, HMCs in fish tissues were significantly increased in fish cultivated in ES fishponds than in KES fishponds. Haematological, immunological, and biochemical alterations of Bolti (Oreochromis niloticus) and Topara (Chelon ramada) fish were significantly different within the different fish species as well as the different fishponds. From the human health perspective, the THQ-HMC and HI-HMC associated with the consumption of muscle suggest a safe non-carcinogenic risk to human health. In contrast, cadmium poses a cancer risk to children who consume the muscular tissue of Bolti fish from ES fishponds, which should be regarded as a warning sign based on data indices and a human health perspective. In order to minimise HMC pollution in the aquaculture sector, it is advisable to take possible assessments and carry out continuous monitoring considering international WHO/FAO assessments.

Heavy metal (As, Cr, and Pb) contamination and associated human health risks in two commercial fish species in Bangladesh

Contamination of fish with metals is a worldwide consumer safety concern. In this study, three metals such as arsenic (As), chromium (Cr), and lead (Pb) were measured in two commonly consumed fish species Oreochromis niloticus (Tilapia) and Pangasianodon hypophthalmus (Pangasius) that are commercially farmed. The concentration of the metals studied was found within the permissible limits. The concentrations of As, Cr, and Pb in tilapia fluctuated, ranging from not detected (ND) to 0.114 mg/kg, ND to 0.009 mg/kg, and ND to 0.085 mg/kg, respectively. For Pangasius, the concentrations were in the range of 0.014 to 0.118 mg/kg for As, ND to 0.02 mg/kg for Cr, and ND to 0.047 mg/kg for Pb. Hierarchical clustering revealed that As was possibly taken up by leachate and groundwater, while Cr and Pb were from contaminated feed. The results of the calculations for estimated daily intake, target hazard quotient, hazard index, and carcinogenic risk made it clear that consumption of the fish studied does not have a significant adverse effect on consumer health. In conclusion, the contamination levels of farmed tilapia and Pangasius sold in the study area are within acceptable limits, but regular monitoring is required to ensure safe production.

Metal bioavailability, bioaccumulation, and toxicity assessment through sediment and edible biota from intertidal regions of the Aghanashini Estuary, India

The sediment cores and edible biota from the intertidal regions of the Aghanashini Estuary were studied for the assessment of metal toxicity. The estuarine sediments received natural input of metals through the weathering of Dharwar and peninsular gneisses, and laterites. The sediments were enriched in Fe, Mn, Zn, Cu, Co and Ni than the upper crustal value. Also, the concentration of Fe, Zn, Cu, Co and Ni was more in the Aghanashini Estuary than other estuaries around the world. The Enrichment Factor (EF) revealed enrichment of Zn, Cu, Co and Ni in sediments, while the Geo-accumulation Index (Igeo) exhibited unpolluted-moderately-strongly polluted class of Fe, Zn, Cu, Co and Ni. The enrichment and pollution of metals in sediments was due to anthropogenic sources (domestic sewage, aquaculture and agricultural discharge) in the estuary. The presence of metals at a high concentration in the residual fraction and at a significant proportion in the bioavailable fractions construed both natural and anthropogenic sources of metal, and their bioavailability in the estuary. The physico-chemical factors (ionic composition, H+ ions, redox potential, and microbial activity) regulated the adsorption and desorption of metals in sediments. The Screening Quick Reference Table (SQUIRT) revealed level of bioavailable Mn and Co higher than the Apparent Effects Threshold (AET) and thus, indicated adverse toxic effects on biota. The Risk Assessment Code (RAC) indicated medium-high-very high risk of Mn, Zn, Co, Cu and Ni to biota. Also, the concentration of Fe, Mn, Zn, Cu and Ni in biota was in excess of permissible limit which pointed to their toxicity to biota and their consumers. The Target Hazard Quotient (THQ) value > 1, and Hazard Index (HI) value > 10 revealed risk of metal toxicity to humans.

The concentration of potentially toxic elements (PTEs) in Iranian rice: a dietary health risk assessment study

In the present study, six potentially toxic elements (PTEs), including chromium (Cr), arsenic (As), cadmium (Cd), lead (Pb), copper (Cu), and nickel (Ni), were determined in 41 domestic rice samples collected from Tehran using ICP-OES (inductively coupled plasma-optical emission spectrometry). The mean concentration of Cd, As, Cu, Pb, Cr, and Ni was found as 0.014 ± 0.01, 0.018 ± 0.005, 2.15 ± 1.84, 0.42 ± 0.31, 0.1 ± 0.16, and 0.48 ± 0.36 mg kg-1, respectively. Possible risks due to ingestion of PTEs via rice consumption for children and adults were assessed by Monte Carlo simulation. The 50th percentile of estimated Cr intake for children through domestic rice consumption exceeded the maximum tolerable daily intake. There was only a potential non-carcinogenic risk for single Cr exposure for children. The 95th percentile of the estimated hazard index (HI) for children and adults was 4.34 and 1.05, indicating a potential non-carcinogenic risk related to multiple PTE exposure. The lifetime cancer risk (ILCR) values derived from Cr, Ni, As, and Cd exposure exceeded the threshold value, indicating a carcinogenic risk due to PTEs' exposure. The deterministic assessment demonstrates that the Tehran population may be at risk through domestic rice consumption. This study indicates that risk related to the exposure to multiple PTEs through the consumption of rice in adults and children in Tehran is recognized as an important issue, thus supporting the importance of cumulative analysis of the risk of exposure to PTEs through food. Finally, national strategic environmental assessment and technological solutions for monitoring and protecting freshwater, soil, waste management, and chemicals as a global concern policy are needed for public health.

Human health risks associated with metals in paddy plant (Oryza sativa) based on target hazard quotient and target cancer risk

Paddy plants (Oryza sativa) contaminated with metals could be detrimental to human health if the concentrations of metals exceed the permissible limit. Thus, this study aims to assess the risk of the concentrations of As, Se, Cu, Cr, Co, and Ni and their distributions in various parts (roots, stems, leaves, and grains) of paddy plants collected from Sekinchan, Malaysia. Both soil and plant samples were digested according to the United States Environmental Protection Agency (USEPA) Method 3050B and the metal concentrations were determined by the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The highest mean translocation factor (TF) was from soil to roots (TF roots/soil ranged from 0.12 to 6.15) and the lowest was from leaves to grain (TF grain/leaves ranged from 0.06 to 0.87). Meanwhile, the bioaccumulation factor (BAF) for all metals was less than 1.0 indicating that paddy plants only absorb metals from the soil but do not accumulate in the grains. The average daily intake for As (1.15 ± 0.25 µg/kg/day) has exceeded the limit proposed by ATSDR and IRIS USEPA (0.30 µg/kg/day). Target cancer risk (TR) of 1.10 × 10^-3 for As through rice consumption indicates that the potential cancer risk exists in one out of 1000 exposed individuals. The results from this study could serve as a reference for researchers and policymakers to monitor and formulate strategies in managing As and other metals in paddy plants, especially in Southeast Asian countries.

Polyploidy and zinc oxide nanoparticles alleviated Cd toxicity in rice by modulating oxidative stress and expression levels of sucrose and metal-transporter genes

The Cd toxicity causes severe perturbations to the plant's growth and development. Here, polyploid and diploid rice lines were treated with zinc-oxide nanoparticles (ZnO-NPs) and Cd, and physiological, cytological and molecular changes were observed. The Cd toxicity significantly reduced plant's growth attributes (such as shoot length, biological yield, dry matter, and chlorophyll contents, which decreased by 19%, 18%, 16%, 19% in polyploid and 35%, 43%, 45% and 43% in diploid rice, respectively), and disturbed the sugar level through the production of electrolytes, hydrogen peroxide, and malondialdehyde. The application of ZnO-NPs significantly alleviated the Cd toxicity in both lines by improving the antioxidant enzymes activities and physiochemical attributes. Semi-thin sections and transmission electron microscope revealed more and different types of abnormalities in diploid rice compared to polyploid rice under Cd stress. Moreover, RNA-seq analysis identified several differentially expressed genes between polyploid and diploid rice, especially metal and sucrose transporter genes. The GO, COG, and KEGG analyses revealed ploidy-specific pathways associated with plant growth and development. In conclusion, ZnO-NPs application to both rice lines significantly improved plant growth and decreased Cd accumulation in plants. We inferred that polyploid rice is more resistant to Cd stress than diploid rice.

Heavy metal(loid)s in agriculture soils, rice, and wheat across China: Status assessment and spatiotemporal analysis

Heavy metal(loid)s (HMs) accumulation in agricultural soils, rice, and wheat is of particular concern in China, while the status and spatio-temporal distribution of HMs in the soil-crops system have been rarely reported at the national scale. This study aimed to summarize the overall pollution status, spatiotemporal patterns, and drivers of HMs in agricultural soil, rice, and wheat nationwide. The metal-polluted data from 1030 agricultural soils, rice, and wheat in China were collected from the literature published from 2000 to 2022. The results showed that Cd was the most prevailing contaminant in soils based on its spatiotemporal distribution and accumulation. The pollution cases and severe pollution percentage of Cd (103 %) and Hg (128 %) show an increasing trend pattern. Mining activities are the main anthropogenic sources of agricultural soil HMs in China. Cd and Pb had the highest exceedance rate in rice (33.5 and 32.2 %) and wheat (25.8 and 30.3 %). The rice from Hunan, Fujian, and Guangxi showed the highest average concentration of Cd and Pb, respectively, while wheat samples from Hubei had the greatest exceedance rate of Pb. Besides, HMs in crops was not usually corresponding to soil HMs but increased gradually from north to south areas. Several mitigation strategies and accurate health risk assessments model of HMs based on bioavailability were also proposed and recommended. Collectively, this review provides valuable information to improve the management of farmland nationwide, optimize the accurate risk assessment, and reduce HMs pollution.

Assessment of Stock Status, Metal Contents with Human Health Risk of Gudusia chapra from Oxbow lake, Bangladesh

The current study is focused on a comprehensive stock assessment of Gudusia chapra to assess the stock status along with feeding habits, essential minerals content and risk to human health from exposure to heavy metals. A total of 723 specimens from the Bukvora Baor, Bangladesh were used to estimate the total body length (TL) and body weight (W) which ranged from 5.5 to 14.5 cm and 1.62-26.45 g, respectively. The estimated asymptotic length (L _∞) of this species (15.38) was in comparison with average length at 10 cm from 723 specimens along with the rate of 0.70 yr^-1 for approaching to asymptotic length. The obtained growth performance index (φ) 2.2 indicates that this species is not economically feasible to bring under aquaculture. At an average annual water surface temperature of 28 °C, natural mortality, 1.71yr^-1 indicating good ecological suitability of Bukvora oxbow lake (Baor). The estimated current exploitation ratio (0.24) reflected under-exploitation status with total instantaneous mortality (2.25 years^-1) and fishing mortality (0.55 years^-1). The recruitment pattern of this species was observed across the year, with main peak occurring during the period of April to May. The estimated total steady state biomass (3.91 metric ton) and MSY (4.40 metric ton) based on length-structured virtual population analysis (VPA) length-structured virtual population analysis (VPA) through FiSAT II schedule indicating the sustainable production of this species. The obtained values of proximate compositions (% of protein, fat, Moisture, ash) showed no significant variations during different seasons throughout the year. The monthly measurements of GaSI showed significant alterations (p < 0.05). The value of essential minerals (Na and Ca) was recorded 9.18 mg and 245.19 mg per 100 g of fish flesh, respectively. Target hazard quotient and Cancer risk for all detected heavy metals were far below the recommended levels by United States Environmental Protection Agency. Therefore, the target fish species from oxbow lake is safe and have no human health risk. Therefore, the outcomes of this research would be very worthwhile in carrying out specific management for G. chapra in Baor ecosystems.

Human Dietary Exposure to Heavy Metals via Rice in Nepal

The effects of exposure to heavy metals (HMs) in rice on human health have become a global public health concern, particularly in countries where rice is consumed as a staple food. The concentrations of HMs, including cadmium (Cd), arsenic (As), lead (Pb), and copper (Cu), in commercial rice samples (n = 170) were analyzed to estimate the HM exposure of consumers in Nepal. The geometric mean concentrations of Cd, As, Pb, and Cu in commercial rice were 15.5 ± 16.0, 43.4 ± 19.6, 16.0 ± 14.0, and 1066 ± 1210 μg/kg, respectively, all below the maximum allowable concentrations (MACs) recommended by FAO/WHO. Generally, the average estimated daily intakes (EDIs) of Cd, As, Pb, and Cu were all below the oral reference doses (RfDs). However, young age groups were exposed to high levels of HMs, and the average EDI of As and the P99.9 EDIs of Cu and Cd were above the corresponding RfDs. The mean hazard index and total carcinogenic risk were 1.13 and 1.04 × 10^-3 respectively, suggesting a potential non-carcinogenic risk (NCR) and a carcinogenic risk (CR) via rice consumption. Arsenic contributed the most strongly to NCR and Cd to CR. Overall, although the HM levels in rice were generally safe, the Nepalese population may be exposed to an elevated health risk from rice consumption.

Contamination, ecological, and health risk assessment of heavy metals and organophosphorus pesticides in single, double, and ratoon cropping of rice: a case study in Mazandaran, North of Iran

This study investigated the contamination and health risk assessment of heavy metals and organophosphorus pesticides in single, double, and ratoon cropping of rice in Mazandaran province, north of Iran. A total of 17 sampling locations in rice farms were selected and soil and rice samples were collected from farms in 5 counties of Mazandaran. Soil and rice samples were then transferred to the lab for further analysis. The concentration of pesticides and heavy metals was then analyzed using gas chromatography-mass spectrometry (GC-MS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Mercury was analyzed using a Leco mercury analyzer. Target hazard quotient (THQ), total target hazard quotient (TTHQ), carcinogenic risk (CR), and total carcinogenic risk (TCR) in children and adults were used. Potential ecological risk also was used to test the possible hazards of heavy metals to the environment. Heavy metals concentration in rice and soil samples in different farming steps revealed different levels. THQ showed no considerable risk in consuming contaminated rice to adults and children considered, while TTHQ revealed potential non-carcinogenic risks. Ni had the most carcinogenic risks to target human groups, and TCR showed carcinogenicity for carcinogenic heavy metals in all stations. Findings showed no ecological risks of metals to the environment. In conclusion, rice farmers in Mazandaran use the lands multiple times during the year to increase the performance, function, quality, and quantity of rice, but the possible toxic effects of heavy metals and pesticides on consumers and the environment should not be overlooked.

Micronutrients and heavy metals in rice farms: the case of Ahvaz and Bawie Counties, Khuzestan Province, Iran

This study addressed micronutrients (Fe, Zn, Cu, Mn, Co) and heavy metals (As, Pb) in the soil and rice crop in Khuzestan Province, Iran. Twenty-eight composite soil and grain samples from the intended rice farms were garnered during harvest time. Concentrations of the elements in the samples and in the grains were, respectively, determined by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry device. The average concentration of As, Fe, Co, Cu, Mn, Pb, and Zn in soil of crop were 2.71, 20,065.8, 10.43, 22.28, 422.28, 5.85, and 47.07 mg/kg, respectively. The physicochemical properties of soil, bioconcentration factor, daily intakes, and health risk assessment of the elements were calculated. The results revealed that the area covered by alkaline saline soils is poor in micronutrients. Bioconcentration factor values of all elements were less than 1. Low levels of bioconcentration factor may be for low levels of nutrients in the soil and physicochemical conditions of the soil. Furthermore, the daily intake of Co (adults' group) and Fe and Zn (children group) was very low. Health risk assessment showed only adults are threatened by non-cancerous diseases due to excessive value of all the elements (HI = 2.53) and cancerous diseases caused by excessive As and Pb (2.86E-04 and 2.01E-05, respectively). Considering that Khuzestan Province is the fourth largest producer of rice in Iran, the lack of micronutrients and the presence of heavy metals in rice produced in the study area can adversely affect consumers. Further investigation is therefore a must in the region.

Investigation of Trace Elements in Vegan Foods by ICP-MS After Microwave Digestion

Veganism is gaining popularity around the world day by day. Vegan nutrition is a diet in which not all animal foods are used. A vegan diet does not contain meat, fish, milk and dairy products, and eggs and consists of vegetables, fruits, grains, legumes, and nuts. Vegan diets maintain energy balances in a wide variety of plant foods. So, health problems can be seen due to nutrient and mineral deficiencies in the long-term continuation of the vegan diet. Due to insufficient intake of vitamins and minerals such as vitamin D, vitamin B12, calcium, iron, and zinc, energy and protein balance in the body may not be achieved by vegan individuals. The contents of aluminum, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, mercury, cadmium, and lead have been analyzed by inductively coupled plasma mass spectrometer (ICP-MS) in 10 different vegan foods purchased from Turkey. Certified reference material (1547 peach leaves) was used for validating the digestion procedure. Dry, wet, and microwave processes were compared, and it was found that the microwave digestion method was the best. Element levels in the analyzed samples were found below the legal limits. The purpose of this work is to investigate the trace element content of various foods used in vegan nutrition.

Meta-analysis of public health risks of lead accumulation in wastewater, irrigated soil, and crops nexus

Lead (Pb) from different sources accumulate in the irrigation water, irrigated soil and in different parts of plants. Reports show contradictory findings and high variability of lead accumulation and associated public health risks. We hypothesized that lead accumulation in irrigation water, soil and edible plants is high enough to be a public health risk. By using the standard procedures for meta-analysis, 24 studies were qualified. The studies included in the meta-analysis are concentrated in few countries with strong authors' key words co-occurrence relationship. The mean concentration of Pb in the irrigation wastewater ranged from 0.0196 ± 0.01 mg/l to 52.4 ± 0.02 mg/l in wastewater and about 50% of the values are beyond the limits for irrigation water standard. The study also showed that the concentration of Pb in the irrigated soil vary significantly from a minimum of 0.04 ± 2.3 mg/l in Ethiopia to a maximum of 441 ± 19.8 mg/l in Iran (P < 0.01). Based on effect size analysis, the weight of the studies ranged from 0.1 to 5.4% indicating that the studies' contribution to the overall effect is barely different. The heterogeneity test statistics also indicates considerable variability between the studies (I² = 98%, P-value < 0.001). The subgroup analysis showed large between-studies heterogeneity in both groups (Tau² = 28.64; T² = 98%). A total of 44 crops were studied, of which 38 were leafy and non-leafy vegetables. Most popular crops including spinach, cabbage and lettuce are most frequently studied crops. In all crops, the Pb level in crops produced by using untreated wastewater are beyond the WHO limit for edibility. In all of the studies, the pollution load index (PLI) and soil accumulation factor (SAF) is much higher indicating that there is a buildup of Pb concentration in wastewater irrigated soil. The plant concentration factor (PCF) calculated shows the high Pb accumulation potential of the edible parts of the crops. The health risk index (HRI) calculated shows that in all of the studied crops from India, Iraq, Morocco and Egypt are much higher than one indicating the high health risk of consumption.

Seasonal behavior and accumulation of some toxic metals in commercial fishes from Kirtankhola tidal river of Bangladesh - A health risk taxation

Contamination of fish with heavy metals (Heavy metals) is one of the most severe environmental and human health issues. However, the contamination levels in tropical fishes from Bangladesh are still unknown. To this end, the evaluated concentrations of arsenic (As), chromium (Cr), cadmium (Cd), and lead (Pb) in 12 different commercially important fish species (Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Glossogobius giuris, Pseudeutropius atherinoides, Polynemus paradiseus, Sillaginopsis panijus, Corica soborna, Amblypharyngodon mola, Trichogaster fasciata, and Wallago attu) were collected from the Kirtankhola River assess human health risk for the consumers, both in the summer and winter seasons. Toxic metals surpassed the acceptable international limits in P. atherinoides, P. paradiseus, S. panijus, C. soborna, and W. attu. The target hazard quotient (THQ) revealed that non-carcinogenic health effects (HI < 1) for children and adults, and the carcinogenic risk (CR) indicated safety. Results show that children are more susceptible to carcinogenic and non-carcinogenic hazards from higher As. The multivariate analysis justified that heavy metals were from anthropogenic actions. The lessening of toxic metals might need strict rules and regulations as metal enrichment would continue to increase in this tidal river from both the anthropogenic and natural sources.

Concentration of potentially harmful elements (PHEs) in eggplant vegetable (Solanum melongena) irrigated with wastewater: a systematic review and meta-analysis and probabilistic health risk assessment

The main objectives of this study were PHEs concentration meta-analysis (Fe, Zn, Cr, Ni, Cu, Pb, and Cd) in eggplant irrigated by wastewater and the following estimation of non-carcinogenic (n-CR) risk for the consumers based on countries. According to the results, the rank order of PHEs concentration in eggplant was Fe (88.3 mg/kg -dry weight) > Zn (10.1 mg/kg -dry weight) > Pb (3.0 mg/kg -dry weight) > Ni (2.7 mg/kg -dry weight) > Cu (1.1 mg/kg -dry weight) > Cd (0.9 mg/kg -dry weight) > Cr (0.05 mg/kg -dry weight). Moreover, n-CR risk showed that all investigated countries (China, India, Pakistan, Turkey, and Jordan) except for United Arab Emirates (UAE) had a considerable n-CR in both age groups (adults and children).

Contamination of breast milk with lead, mercury, arsenic, and cadmium in Iran: a systematic review and meta-analysis

Breast milk is a complete food for the development of the newborn, but it can also be an important route for environmental pollutants transmission to the infants. This study was aimed to evaluate the status of heavy metals including lead (Pb), mercury (Hg), cadmium (Cd) and arsenic (As) in the breast milk of Iranian mothers. The international databases including Scopus, PubMed, Web of Science and the Persian electronic databases including Scientific Information Database, IranMedex and Magiran were examined to find relevant articles published until July 2021. A total of 23 studies examined the levels of toxic metals in Iranian breast milk samples. According to the findings, the pooled average concentrations (µg/L) of Pb, Cd, Hg and As were 25.61, 2.40, 1.29 and 1.16, respectively. The concentration of Hg and Pb in colostrum milk was more than twice of mature milk. The Hg mean concentration in the breast milk of mothers with at least one amalgam-filled tooth was approximately three times that of mothers without amalgam-filled teeth. Risk assessment analysis indicated that the intake of Pb and Hg by infants through breastfeeding can be considered a health concern in Iran. It seems necessary to reduce the Pb exposure of pregnant and lactating women in Iran. However, more extensive studies are needed to clarify the toxic metals' exposure status of infants through breast milk in other parts of the country.

Concentrations of essential and toxic elements and health risk assessment in brown rice from Qatari market

Twenty-two brown rice varieties available in the Qatari market were analyzed for essential and toxic elements by ICP-MS. Found concentrations (µg/kg) were: As: 171 ± 78 (62-343), Cd: 42 ± 60 (4-253), Cr: 515 ± 69 (401-639), Pb: 6 ± 7 (<MDL-26), and U: 0.1 ± 0.5 (<MDL-2). One third of the samples contained high levels of arsenic. Significant differences (p < 0.008) in concentrations were observed for many elements based on both the grains' country of origin and size. Calculated carcinogenic risk according to published speciation data of inorganic arsenic and chromium(VI) available in the literature for rice is > 1 in million, may possibly be > 1 in 10,000 based on conservatively high brown rice consumption rates of 200 g/d or 400 g/d in Qatar. These elevated risks may be applicable to specific population subgroups with diabetic conditions who consume only brown rice. Non-cancer risks are mainly derived from Mn, V, Se, and Cd with a hazard index > 1 from some brown rice samples.

Bioaccumulation and health risk assessment of exposure to potentially toxic elements by consuming agricultural products irrigated with wastewater effluents

Potentially toxic elements (PTEs) have many adverse health effects due to bioaccumulation capability and their long persistence in the environment. As a renewable water source, the effluents of municipal wastewater treatment systems have been used to irrigate agricultural products widely. However, the evidence on the bioaccumulation of PTEs in crops irrigated with these effluents is still scarce, with no available study in low and middle-income countries. Therefore, this study aimed to assess the PTEs concentration in the soil and crops irrigated with effluents of Sabzevar wastewater treatment plant and the related health risk by that. The clustered method was used to determine the soil and craps samples. Seventy cumulative samples were randomly prepared in summer and autumn 2016 and 2017 from crops, soil and effluent. Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure PTEs. The health risk of exposure to PTEs was assessed using Monte Carlo simulation technique. Kruskal Wallis test and Posthoc Tukey HSD test were used to assess the mean difference of PTEs between soil, effluent and crops as well as between crops together. The bioaccumulation factor (BAF) magnitude order in different crop samples was Cd > Sr > Cu > Pb > Zn > Co > As > Cr > Ni, respectively. The Cd accumulation in Sugar beet plant was significantly higher than in other samples. The highest hazard quotient (HQ) based on single PTEs was observed for As (mineral) (mean: 5.62 × 10^-1 and percentile 95th: 2.13) in Okra. Regarding total HQ (THQ), the highest and lowest mean (percentile 95th) values were 1.50 (3.22) and 2.40 × 10^-1 (4.01 × 10^-1) for Okra and Watermelon, respectively. The mean concentrations of Co, Cr, Ni and Zn were significantly higher in crops compared to soil and influent samples. Posthoc tests indicated that the concentration of PTEs between investigated crop samples were not statistically significant different (p > 0.05). Overall, our study suggested that irrigation with the effluent of stabilization pond wastewater treatment system exerts a potential health risk due to bioaccumulation of PTEs in crops.

Bioaccumulation and potential human health risks of metals in commercially important fishes and shellfishes from Hangzhou Bay, China

Hangzhou Bay is facing severe anthropogenic perturbation because of its geographic position. We studied species-specific bioaccumulation of metals in commercially important fishes and shellfishes, and calculated the potential human health hazards through their consumption, which has not been reported earlier from this area. The hierarchy of metal concentration in organisms was in the decreasing order of Zn (10.32 ± 7.13) > Cu (2.40 ± 2.66) > As (0.42 ± 0.26) > Cr (0.11 ± 0.08) > Cd (0.07 ± 0.07) > Pb (0.05 ± 0.02) > Hg (0.012 ± 0.009). Except for Cd and As concentrations in fishes, metal concentrations have not exceeded the national and international guideline values. P. laevis and P. trituberculatus were the most bioaccumulative of the species studied. According to the non-carcinogenic risk assessment, children were more susceptible to metal contamination than adults. The carcinogenic risk (CR) values indicated that children were likely to experience carcinogenic threats for taking cancer-causing agents As and Cd through fish consumption. In terms of organisms, intake of two crab species, P. trituberculatus and E. sinensis, as well as the oyster species P. laevis, could be detrimental to consumers.

Physicochemical, digestive and rheological properties of protein from tuna by subcritical dimethyl ether: Focus on process-related indexes

The process-related physicochemical, digestive and rheological properties of protein prepared by subcritical dimethyl ether extraction (SDEE) were comprehensively investigated and compared with those obtained by pH-shift, to study the industrial potential of SDEE. Two different materials from tuna (meat and liver) were studied in parallel, and SDEE had similar effects on the proteins in them. The protein component was almost unchanged before and after SDEE, while the content of water-soluble protein and alkali-soluble protein was substantially reduced and increased after pH-shift, respectively. We also found that SDEE had superior ability to pH-shift to conserve light metals, remove lipids and heavy metals, and maintain protein structure. Furthermore, SDEE-produced protein powders were easier for humans to digest, and their gelation and emulsification were also superior to those prepared by pH-shift. The aforementioned results suggest that SDEE can remove more impurities, and the obtained protein has outstanding potential in industrial applications.

Metals Bioaccumulation in 15 Commonly Consumed Fishes from the Lower Meghna River and Adjacent Areas of Bangladesh and Associated Human Health Hazards

The lower Meghna River, the easternmost part of the Ganges Delta, faces severe anthropogenic perturbations as it receives a huge discharge and industrial effluents. To measure the metal concentrations and human health hazards, edible tissues of 15 commercially important fish species were collected from the local fish markets and the lower Meghna River, Bangladesh. Trace and heavy metals such as Pb, Cr, Cu, Zn, Mn, Fe, Hg, Ni, Ca, Co, Se, Rb, Sr, and As were detected using the Energy Dispersive X-ray Fluorescence (EDXRF) method. The hierarchy of mean metal concentrations obtained was: Fe (162.198 mg/kg) > Zn (113.326 mg/kg) > Ca (87.828 mg/kg) > Sr (75.139 mg/kg) > Cu (36.438 mg/kg) > Se (9.087 mg/kg) > Cr (7.336 mg/kg) > Mn (6.637 mg/kg) > Co (3.474 mg/kg) > Rb (1.912 mg/kg) > Hg (1.657 mg/kg) > Ni (1.467 mg/kg) > Pb (0.521 mg/kg) > As (BDL). Based on the metal concentration obtained, the carnivorous species contained more metals than omnivores and herbivores. Similarly, the euryhaline and benthic feeder fishes had more metals than the stenohalines and demersal fishes. The metal pollution index (MPI) suggested that the highly consumed fish species Tilapia (Oreochromis mossambicus) and Rui (Labeo rohita) accumulated higher metals than other fishes. Both the Targeted Hazard Quotient (THQ) and Hazard Index (HI) values for adult and child consumers were <1, indicating that consumers would not experience the non-carcinogenic health effects. Although children were more susceptible than adults, carcinogenic risk (CR) exposure of Cr for all the consumers was found in the acceptable range (10−6 to 10−4), but the CR exposure of Pb was negligible for all the consumers. The correlation, principal component analysis (PCA), and cluster analysis were conducted to identify the sources of metals identified from the fish tissue. The results indicated that the probable sources of the pollutants were anthropogenic, arising from agricultural activities, electroplating materials, and lubricants used near the study area. However, the present study showed a different metal concentration in the samples at different levels but within the threshold levels non-carcinogenic and carcinogenic health risks; hence, the fishes of the area, in general, are safe for human consumption.

Microplastics and trace metals in fish species of the Gulf of Mannar (Indian Ocean) and evaluation of human health

The importance of microplastic (MPs) contamination in marine environments is reflected by increasing number of studies in fish species. Some even dedicated to the toxicological effects from the ingestion. Microplastics (MPs) and their trace metal composition were examined in the muscle and intestine of five commercially important fish species (i.e., Sufflamen fraenatus, Heniochus acuminatus, Atropus atropos, Pseudotriacanthus and Leiognathus brevirostris) from Thoothukudi at the Gulf of Mannar coast in south India. The abundance and morphology of MPs (size, shape, and texture) in muscle and intestinal were investigated by micro-Fourier Transform Infrared Spectroscopy (μ-FT-IR) and atomic force microscope (AFM). ICP-OES was used to investigate the adsorption/leaching of trace metals in microplastics in order to assess health risk for adults and children. Particles of 100-250 μm and white color dominated, and the mean abundances (items/100 g) of total MPs were more in Pseudotriacanthus (muscle: 51.2; intestine: 50.1) compared to Heniochus acuminatus (muscle: 9.6; intestine: 15), Leiognathus brevirostris (muscle: 12; intestine: 13.2) and Atropus atropus (muscle: 15.2; intestine: 44.1). Polyethylene (35.3%), polypropylene (27.2%), polyamide (nylon) (22.2%) and fiber (15.3%) represented the MPs present in muscles, and polyamide (nylon) (30.2%), polyethylene (28.1%), polypropylene (25.9%), and fiber (15.8%) composed the intestine MPs. We estimated possible consumption of 121-456 items of MPs/week by adults and about 19-68 items of MPs/week by children by considering the sizes of safe meals. Zn, Cu, Mn and Cr in these fish species reflected influence of the sewage waste. However, the non-carcinogenic risk evaluated through EDI, THQ, HI, and CR did not suggest any immediate health problem for the consumers.

Heavy Metals in the Fish Tenualosa ilisha Hamilton, 1822 in the Padma-Meghna River Confluence: Potential Risks to Public Health

Hilsa shad (Tenulosa ilisha) is Bangladesh's most important single-species fishery that contributes to 11% of total catch and employment for millions of people. However, heavy metals (HMs) toxicity in the edible organs of T. ilisha and their plausible public health threats have received weak attention. To provide insights on this issue, we determined, using ICP-MS, the concentration of Zn, Cu, Cr (VI), Pb, and Cd in the edible organs of five different sizes of T. ilisha and the surface water collected from the Padma-Meghna River confluence, Chandpur (Bangladesh). Multivariate analysis indicated that T. ilisha gills and liver contained higher HMs than muscle, and the surface water was below the safety limits. The study revealed that only Cr crossed the safety limits and bioaccumulated in the smaller-sized gills and liver. To assess the public health risks, target hazard quotient (THQ), total THQ (TTHQ) and carcinogenic (CR) risks were calculated. Only Cr imposed non-carcinogenic risks to consumers, while TTHQ showed higher chronic health risks. There was no CR risk measured for consumers, except for the largest-sized gills for children. Randomly positive relations between HMs and sizes were found; whereas, consistently positive relations were found among the tissue types. The outcomes of our study may aid policymakers in managing pollutants, especially the Cr sources in the greater Chandpur regions.

Translocation of Soil Arsenic towards Accumulation in Rice: Magnitude of Water Management to Minimize Health Risk

Globally, the risk of arsenic (As) contamination in soil and rice is well documented across the globe. In Bangladesh, drinking water and rice are two major exposure pathways of As to humans. Therefore, the efficiency of recent technologies to reduce rice As and associated human health risks still need to be deeply investigated. In this direction, a pot experiment was performed to investigate the impact of soil As and agronomic irrigation management on rice (cv. BRRI dhan28) growth, yield, As accumulation, and finally, health risks to humans from consuming rice. Treatment combinations were made with three levels of As (0, 20, and 40 mg kg−1) having two irrigation procedures, including alternate wetting and drying (AWD) and traditional continuous flooding (CF). According to the findings, As pollution in the soil lowered the yield contributing features and rice yield, including panicle length, filled grains per panicle, sterile grains per panicle, 1000-grain weight, grain yield, and straw yield. AWD water management significantly improved the growth performance and productivity of rice. Grain yield was increased by 13% in AWD compared to CF. Rice grain and straw As concentrations were increased to 0.56 mg kg−1 and 15.10 mg kg−1, respectively, in soil with 40 mg kg−1 As and CF water management. AWD treatment significantly reduced grain and straw As contents by 16% and 28%, respectively. Increased grain, straw, and total As uptake was noticed with higher soil As concentrations. The study also found that rising soil As raised non-carcinogenic risks (HQ > 1) and carcinogenic risks (CR > 1.010–4) while AWD lowered health risks compared to CF. Thus, rice farming using AWD irrigation could be a viable and long-term solution for reducing As contamination in rice and associated human health hazards.

Levels and health risk assessment of heavy metals in dried fish consumed in Bangladesh

As a cheap source of high-quality protein, healthy fats and essential nutrients, dried fish is a common item in the daily diet of the Bangladesh populace. In this study, ten types of widely consumed dried fish (H. neherius, T. lepturu, P.chinensis, P. affinis, A. mola, P. microdon, I. megaloptera, C. dussumieri, L. calcarifer, and G. chapra) were analyzed for Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Hg, Pb, Ni and As by using an Energy Dispersive X-ray Fluorescence (EDXRF) technique. The concentration of the studied metals was found in the order Fe > Zn > Hg > Cu > Se > Cr > Mn > Co > Rb > Pb, while As and Ni were below the limit of detection. All fish species showed moderate to high pollution, where the species H. Neherius and P. Chinensis are the most and least polluted ones, respectively. The probable source of contamination is the leaching from the drying pans into the fish samples, atmospheric deposition, anthropogenic contamination, etc. of the water body where these fish were harvested. The calculated hazard index for the general population was below the maximum limiting value (i.e., < 1) except for Hg to children. The carcinogenic risk showed values lower than the acceptable limit for cancer risks (10^–6 to 10^–4). Periodic monitoring of trace metals in the aquatic organisms along with fish is recommended to avoid any unexpected health hazards caused by the toxic heavy metals via fish consumption.

Assessment of quality and safety of meats from various animal species in the Shuchinsk-Burabay resort zone, Kazakhstan

Aim:

This study aimed to determine the food safety and protein adequacy of meats from various animals in the Shuchinsk-Burabay resort zone.

Materials and Methods:

Samples of meat were collected from markets “Zhomart” and “Kausar.” Two hundred and ninety-eight samples of meat were obtained: beef - 166, horse - 42, pork - 67, mutton - 8, and poultry - 15. From each carcass, part of the carcass, point samples were taken to form an average sample and conduct research. Analyses used inductively coupled plasma mass spectrometry and liquid chromatography. The determination of amino acid composition was carried out following the chromatographic method for determining the amino acid composition of meat proteins.

Results:

The quality of meats from the resort zone was lower than recommended due to the reduced content of essential amino acids, including valine, lysine, isoleucine, and phenylalanine. Concentrations of heavy metals and radionuclides did not exceed maximum permissible limits, and trace concentrations of arsenic, cadmium, and lead were detected in all meat samples, except beef. The latter meat showed increased concentrations of mercury.

Conclusion:

In terms of quality indicators, all types of meat met standards; however, pork protein displayed the most favorable amino acid composition, both for content of essential amino acids and the ratio of amounts of essential to non-essential amino acids. For content of heavy metals, poultry and pork meats were safest.

The capacity of ion adsorption and purification for coniferous forests is stronger than that of broad-leaved forests

In the past few decades, industrialization has caused a large number of pollutants to be released into the atmosphere. Forest ecosystems play an important function in regulating the biogeochemistry and the circulation of metal ions pollutants. Forest ecosystems affect the absorption of pollutants and dissolution of nutrients from the atmosphere and vegetation canopy, thereby influencing the content and composition of forest floor leachate and soil solution. This study examined changes in acid anions (NO₃^-, SO₄^2-, Cl^-) and metal cations (K⁺, Ca²⁺, Na²⁺, Mg²⁺, Fe³⁺, Pb²⁺, Cu²⁺, Cd²⁺) in rainfall, throughfall, stemflow, and forest floor leachate for five different forests (Larix principis-rupprechtii, Picea wilsonii, Picea crassifolia, Betula platyphylla and Rhododendron communities). The results showed that the enrichment capacity of acid anions and metal cations in the vegetation canopy of the coniferous forests (L. principis-rupprechtii, P. wilsonii, P. crassifolia) was stronger than that of the broad-leaved forests (B. platyphylla and Rhododendron communities). The content of acid anions and metal cations in stemflow of coniferous forests were 3.7-5.6 times and 0-9.3 times higher than those of broad-leaved forests, respectively. Corresponding values in throughfall were 1-1.4 times and 0.3-2.4 times, respectively^. The contents of NO₃^-, Cl^-, K⁺, Mg²⁺, Fe³⁺, Pb²⁺, Cu²⁺, and Cd²⁺ in leachate filtered from the soil layers that are deepening gradually showed consistent decreasing trend for all the forest stands. In addition, NO₃^-, Cl^-, K⁺, Mg²⁺, Fe³⁺, and Pb²⁺ were also concentrated in the topsoil_, except for Cu²⁺ and Cd²⁺. Nevertheless, SO₄^2- and Na⁺ were concentrated in the subsoil, whereas Ca²⁺ was concentrated in the upper soil layers. Soil organic carbon (SOC) and total nitrogen (TN) contents in coniferous forest stands were 20-37% and 34-63% higher than those in broad-leaved forest stands, respectively. This results also shown that the contents of OC and TN has a strong correlation with the content of partial metal cations in soil and litter, indicating that coniferous forest stands had stronger ion scavenging and adsorption capacity in soil layer and litter layer than broad-leaved forest stands. Therefore, L. principis-rupprechtii, P. wilsonii, P. crassifolia had higher air pollutant adsorption and soil pollution remediation capacities than the other two forests. Thus, we recommend planting coniferous tree species (L. principis-rupprechtii, P. wilsonii and P. crassifolia) for eco-rehabilitation and water purification to improve the ecological service function of forest ecosystems.

The Response of the Associations of Grass and Epichloë Endophytes to the Increased Content of Heavy Metals in the Soil

The rapid development of civilization increases the area of land exposed to the accumulation of toxic compounds, including heavy metals, both in water and soil. Endophytic fungi associated with many species of grasses are related to the resistance of plants to biotic and abiotic stresses, which include heavy metals. This paper reviews different aspects of symbiotic interactions between grass species and fungal endophytes from the genera Epichloë with special attention paid to the elevated concentration of heavy metals in growing substrates. The evidence shows the high resistance variation of plant endophyte symbiosis on the heavy metals in soil outcome. The fungal endophytes confer high heavy metal tolerance, which is the key feature in its practical application with their host plants, i.e., grasses in phytoremediation.

Bioaccessibility and speciation of arsenic in children's diets and health risk assessment of an endemic area in Bangladesh

This study determines the bioaccessibility of toxic and carcinogenic arsenic (As) in composite food samples and evaluates potential exposure from food intake in Bangladesh children. Total As (tAs), inorganic As (iAs) and bioaccessible As (BAs) in food composite samples consumed by children were compared between an exposed and a control group (based on As in drinking water). Total As concentrations in composite food samples of children exposed to mean As level of 331 µg/l in drinking and cooking water ranged from 586 to 1975 µg/kg, dry weight over 76-90 µg/kg in the unexposed group. Average iAs in food composites was 73.9% (range: 49.3-90.8%). The fraction of BAs using gastric and gastrointestinal phases was 91 ± 13% and 98 ± 11%, respectively. Daily intake of iAs in the exposed group ranged from 0.41 to 6.38 µg per kg body weight (BW), which was much higher than the unexposed group (0.08-0.15 µg per kg BW). High iAs content and BAs in composite food samples indicated the elevated risk to exposed children. Further research should include both adults and children using larger sample size to determine overall As exposure from food intake in Bangladesh, attention must be given to lowering of As in food.

A Systematic Review and Meta-analysis to Investigate the Correlation Vegetable Irrigation with Wastewater and Concentration of Potentially Toxic Elements (PTES): a Case Study of Spinach (Spinacia oleracea) and Radish (Raphanus raphanistrum subsp. sativus)

Water shortage and stress around the world lead to the reuse of wastewater in many sectors while the recycling of water in agriculture as one of the most consumed sectors can boost the contamination of crops by potentially toxic elements (PTEs). Therefore, this study was aimed to investigate the correlation between the accumulation of PTEs (Fe, Zn, Cr, Ni, Cu, Pb, As, Cd, and Se) in edible parts of spinach and radish plants and sewage irrigation by the aid of a meta-analysis. Moreover, the non-carcinogenic risk (N-CR) and carcinogenic risk (CR) for health risk assessment of consumers were assessed through actual total target hazard quotient (TTHQact) and carcinogenic risk (CRact). After the screening process, 51 articles with 75 studies were included. According to findings, the rank order of PTEs in spinach and radish were Fe > Zn > Cr > Cu > Ni > Pb > Cd > As > Se and Fe > Zn > Cr > Ni > Cu > Pb > As > Cd > Se, respectively. PTE adsorption by edible parts of spinach (leafy vegetable) was higher than radish. The health risk assessment shows that residents in Iran, India, and China are at N-CR while the population of Iran, India, and Pakistan are facing CR.

Cellular strategies against metal exposure and metal localization patterns linked to phosphorus pathways in Ochrobactrum anthropi DE2010

Cytotoxic, chemical, biochemical, compositional, and morphometric responses were analyzed against heavy metal exposure in Ochrobactrum anthropi DE2010, an heterotrophic bacterium isolated from Ebro Delta microbial mats (Tarragona, NE Spain). Several parameters of effect and exposure were evaluated to determine tolerance to a range of cadmium (Cd), lead (Pb(II)), copper (Cu(II)), chromium (Cr(III)), and zinc (Zn) concentrations. Additionally, removal efficiency, polyphosphate production and metal localization patterns were also analyzed. O. anthropi DE2010 showed high resistance to the tested metals, supporting concentrations of up to 20 mM for Zn and 10 mM for the rest of the elements. The bacterium also demonstrated a high removal capacity of metals-up to 90 % and 40 % for Pb(II) and Cr(III), respectively. Moreover, polyphosphate production was strongly correlated with heavy metal concentration, and three clear cell localization patterns of metals were evidenced using compositional and imaging techniques: (i) extracellular in polyphosphate granules for Cu(II); (ii) in periplasmic space forming crystals with phosphorus for Pb(II); and (iii) intracytoplasmic in polyphosphate inclusions for Pb(II), Cr(III), and Zn. The high resistance and metal sequestration capacity of O. anthropi DE2010 both highlight its great potential for bioremediation strategies, especially in Pb and Cr polluted areas.

Assessment of Rice Marketed in Iran with Emphasis on Toxic and Essential Elements; Effect of Different Cooking Methods

Rice is one of the most valuable nutrients in the diet of most people in the world. The aim of this study was to evaluate the effect of various pre-cooking (washing, soaking) and cooking processes (traditional and rinse) of rice on the amount of toxic and essential elements in the various brands of rice in Iran and assessing human health risks from their carcinogenic and non-carcinogenic effects. For this purpose, totally, 144 sample sizes were examined from three brand (Iranian (n = 48), Pakistani (n = 48), and Indian (n = 48)) in order to the amount of toxic and essential elements using inductively coupled plasma-optical emission spectrometry. The results showed that pre-cooking processes such as washing and soaking in the rinse method were significantly effective in removal toxic metals than the traditional method, so that the most changes were observed for potassium and aluminum metals. The estimated daily intakes of copper, magnesium, manganese, iron, and zinc in different cooking methods were 1.19-1.2%, 0.29-0.32%, 1.01-1.23%, 0.4-0.98%, and 0.9-1.32%, respectively. The Monte Carlo simulation results showed that the rank order of toxic metals of cooked rice based on target hazard quotients value was arsenic > chromium > cadmium > mercury > lead > aluminum, respectively. The result of cancer risk probability was lower than the safe risk limits (1E-4), representing no remarkable cancer risk probability that was due to ingestion of rice for adults and children in Iran. According to the this results, it is recommended to use the rinse method due to further reduction of metals especially toxic metals for rice samples, although the amount of essential elements was also removed by this method.

Bioaccumulation of mercury in Haemulopsis elongatus and Pomadasys macracanthus from the SE Gulf of California: condition indexes and health risk assessment

Mercury (Hg) was measured in the muscle, liver, and gonads of Haemulopsis elongatus and Pomadasys macracanthus from Mazatlán (SE Gulf of California) to determine the relationships of the hepatosomatic index (HSI) and gonadosomatic index (GSI) of fish with Hg concentrations in the corresponding tissues. Health risk to consumers was assessed by using the hazard quotient (HQ), considering the average rate of fish consumption in Mexico and Hg concentration in the edible tissue. In H. elongatus, the highest Hg levels were measured in the liver (3.748 μg g^-1); in P. macracanthus, the highest Hg concentration was quantified in the muscle (0.574 μg g^-1). In P. macracanthus, the HSI was negatively correlated with Hg concentration in the liver; in H. elongatus, there was also a negative relationship between Hg levels in gonads and the GSI. Mean HQ values in Haemulopsis elongatus (0.005) and Pomadasys macracanthus (0.002) were below the value (HQ ≥ 1) of concern. The significant reduction of HSI and GSI with Hg increase in the liver and gonads may suggest that Hg bioaccumulation in these fish shows adverse physiological effects. Though HQ values in both species were below the unit, i.e., the consumption of the muscle from this species does not represent a health risk, it is necessary to carry out surveys of fish consumption rates in coastal areas of Mexico to do a more precise health risk assessment associated to Hg intake.

Comprehensive review of the basic chemical behaviours, sources, processes, and endpoints of trace element contamination in paddy soil-rice systems in rice-growing countries

Rice is the leading staple food for more than half of the world's population, and approximately 160 million hectares of agricultural area worldwide are under rice cultivation. Therefore, it is essential to fulfil the global demand for rice while maintaining food safety. Rice acts as a sink for potentially toxic metals such as arsenic (As), selenium (Se), cadmium (Cd), lead (Pb), zinc (Zn), manganese (Mn), nickel (Ni), and chromium (Cr) in paddy soil-rice systems due to the natural and anthropogenic sources of these metals that have developed in the last few decades. This review summarizes the sources and basic chemical behaviours of these trace elements in the soil system and their contamination status, uptake, translocation, and accumulation mechanisms in paddy soil-rice systems in major rice-growing countries. Several human health threats are significantly associated with these toxic and potentially toxic metals not only due to their presence in the environment (i.e., the soil, water, and air) but also due to the uptake and translocation of these metals via different transporters. Elevated concentrations of these metals are toxic to plants, animals, and even humans that consume them regularly, and the uniform deposition of metals causes a severe risk of bioaccumulation. Furthermore, the contamination of rice in the global rice trade makes this a critical problem of worldwide concern. Therefore, the global consumption of contaminated rice causes severe human health effects that require rapid action. Finally, this review also summarizes the available management/remediation measures and future research directions for addressing this critical issue.

Nitric Oxide Cooperates With Auxin to Mitigate the Alterations in the Root System Caused by Cadmium and Arsenic

Oryza sativa L. is a worldwide food-crop frequently growing in cadmium (Cd)/arsenic (As) polluted soils, with its root-system as the first target of the pollutants. Root-system development involves the establishment of optimal indole-3-acetic acid (IAA) levels, also requiring the conversion of the IAA natural precursor indole-3-butyric acid (IBA) into IAA, causing nitric oxide (NO) formation. Nitric oxide is a stress-signaling molecule. In rice, a negative interaction of Cd or As with endogenous auxin has been demonstrated, as some NO protective effects. However, a synergism between the natural auxins (IAA and/or IBA) and NO was not yet determined and might be important for ameliorating rice metal(oid)-tolerance. With this aim, the stress caused by Cd/As toxicity in the root cells and the possible recovery by either NO or auxins (IAA/IBA) were evaluated after Cd or As (arsenate) exposure, combined or not with the NO-donor compound sodium-nitroprusside (SNP). Root fresh weight, membrane electrolyte leakage, and H2O2 production were also measured. Moreover, endogenous IAA/IBA contents, transcription-levels of OsYUCCA1 and OsASA2 IAA-biosynthetic-genes, and expression of the IAA-influx-carrier OsAUX1 and the IAA-responsive DR5::GUS construct were analyzed, and NO-epifluorescence levels were measured. Results showed that membrane injury by enhanced electrolyte leakage occurred under both pollutants and was reduced by the treatment with SNP only in Cd-presence. By contrast, no membrane injury was caused by either exogenous NO or IAA or IBA. Cd- and As-toxicity also resulted into a decreased root fresh weight, mitigated by the combination of each pollutant with either IAA or IBA. Cd and As decreased the endogenous NO-content, increased H2O2 formation, and altered auxin biosynthesis, levels and distribution in both adventitious (ARs) and mainly lateral roots (LRs). The SNP-formed NO counteracted the pollutants' effects on auxin distribution/levels, reduced H2O2 formation in Cd-presence, and enhanced AUX1-expression, mainly in As-presence. Each exogenous auxin, but mainly IBA, combined with Cd or As at 10 µM, mitigated the pollutants' effects by increasing LR-production and by increasing NO-content in the case of Cd. Altogether, results demonstrate that NO and auxin(s) work together in the rice root system to counteract the specific toxic-effects of each pollutant.

Heavy metals and probabilistic risk assessment via rice consumption in Thailand

In this study, heavy metals including Cr, Mn, Co, Ni, Cu, Zn, As, and Cd in 55 Thai local rice (4 varieties) were measured using ICP-MS. Health risks were estimated from various Thai population groups, classified according to ages and genders. The potential impact on Thai population who consumed Thai local rice contained heavy metals was assessed by means of probabilistic approach. The hazard quotient (HQ) for non-carcinogenic risks from heavy metal exposure was below the threshold limit of 1 for all rice varieties except Mn in Pka Am Pun rice and As in Pka Am Pun rice, Jek Chuey Sao Hai rice, and Leb Nok rice. Only the hazard index (HI) for consumption of Khaowong Kalasin sticky rice was below 1. The maximum cancer probabilities over the lifetime consumption of Thai local rice were in the range of 5 in 10,000 to 3 in 1000 chances in developing cancer.

Toxic element (As and Hg) content and health risk assessment of commercially available rice for residents in Beijing based on their dietary consumption

Arsenic (As) and mercury (Hg) are toxic elements that are often classified as heavy metals, much like cadmium (Cd) and lead (Pb) and others. In this study, we determined the As and Hg contents in rice samples obtained from commercially available rice in Beijing and the health risks associated with daily dietary exposure to As and Hg by the consumption of this rice. Furthermore, the pollution levels of the rice were evaluated based on the Nemerow index. For this purpose, we collected 353 rice samples from 16 municipal districts in Beijing and determined the As and Hg contents in these samples by microwave digestion and inductively coupled plasma mass spectrometry (ICP-MS). The results were as follows: (i) the average content of As in the collected rice samples was 154.91 μg/kg (95% confidence interval (CI) of 139.90-169.92 μg/kg), and the average content of Hg was 2.02 μg/kg (95% CI of 1.25-2.79 μg/kg), which did not exceed the limits established by China's National Standard; (ii) the Nemerow index indicated that the As and Hg contents in these rice samples were safe; (iii) the dietary exposure to As and Hg by rice consumption was, respectively, 15.35 μg/day and 0.20 μg/day, which accounted for 12.91% and 3.35% of the total dietary exposure, respectively; (iv) the hazard quotients (HQs) of As and Hg by the dietary consumption of rice were, respectively, 0.77 and 0.03, and both the HQ and hazard index (HI is 0.8) were less than one. These results indicate that dietary exposure to As and Hg would have no detrimental effect on the health of the residents in the study area; however, the possible carcinogenesis by As in these residents warrants serious attention.