Carcinogenic and non-carcinogenic evaluations of heavy metals in protein foods from southwestern Nigeria

Carcinogenic and non-carcinogenic health risk assessment of heavy metals in the offal of animals from Felele Abattoir, Lokoja, Nigeria

The consumption of metal-contaminated offal of animals will affect the health of humans. Thus, the research determined the concentrations of heavy metals in the offal and muscle tissues of cows, goats, and ram slaughtered at the main abattoir in Lokoja, northcentral Nigeria. Furthermore, an evaluation was carried out to assess the potential health hazards faced by the indigenous population due to the consumption of heavy metals from these animals. The mean concentrations of metals (Al, Cd, Cr, Ni, and Pb) in the kidney, liver, and muscle of cows, goats, and rams were determined using Inductively Coupled Plasma Optical Emission Spectrometry. Estimated daily intake of the metals, hazard quotient, hazard index, and cancer risk were calculated. All internal organs had Ni levels above the regulatory threshold limit. The average concentration of Pb in the muscle tissue and liver of the tested animals exceeded the permissible limits by the WHO. Similarly, the concentration of Cd in the muscle tissues was above the Maximum Permissible Limit (MPL) of 0.05 mg kg-1. Except for cow kidneys, all internal organs contain Cr levels below the MPL (1.0) limit. The THQ value for the metals was < 1 except Cd. It indicates potential health risks due to Cd. The calculated HI values were > 1. The percentage contribution of Cd to the HI value was the highest. The observed sequence is Cd > Ni > Cr > Pb > Al. The results show that eating the offal and muscle under investigation has a carcinogenic effect.

Health effects of heavy metals in meat and poultry consumption in Noakhali, Bangladesh

This study examined the quantities of heavy metals (Cd, Cr, Pb, Ni, Fe, and Cu) in commercially available meat, poultry, and game products in Noakhali, Bangladesh, and their potential health effects, as heavy metal contamination poses a significant food safety risk to human health Atomic Absorption Spectrophotometry was used to analyze heavy metals, and the health risk assessment was based on Estimated Daily Intake (EDI), Targeted Hazard Quotient (THQ), Total THQ, and Total Carcinogenic Risk (TCR). Most samples exceeded Maximum Allowable Concentrations (MAC) for heavy metals. The EDI value of Cd, Pb, and Cr for duck liver, goat liver, and pigeon brain, were higher than the Maximum Tolerable Dietary Intake (MTDI). Children had 1.28 times higher HI values than an adult. The calculation of THQ of all elements in adults and children was in the order of Cu; Pb; Ni; Cr; Cd; and Fe. The calculated TTHQ values were in the range of 0.051 to 1.988 and 0.047 to 3.975 for adults and children, respectively. The TCR values for Cd in poultry liver, brain, and meat, Sonali chicken, cow, pigeon, duck, and goat liver were higher than the reference value for adults and children, suggesting a potential cancer risk. The average exposure to lead leads to an increase in blood pressure by 0.47 mmHg and a decrease in IQ score by 1.94 points. The present study reveals the need to determine strong relationships between heavy metal exposure and food supply.

Probabilistic health risk assessment of heavy metals (Cd, Pb, and As) in Cocoa powder (Theobroma cacao) in Tehran, Iran market

The concentrations of toxic elements were analyzed by using Flame Atomic Absorption Spectrophotometer (FAAS). Moreover, the human health risk was estimated by Total Target Hazard Quotient (TTHQ) and Cancer Risk (CR) in Monte Carlo Simulation (MCS) technique. The mean concentrations (mg/kg) of Cd (0.08 ± 0.08), Pb (0.23 ± 0.46), and As (0.06 ± 0.04), were in a good compliance with ISO (Iranian standard organization). TTHQ for adults and children was equal to 0.009 and 0.042, respectively and also mean CR in adults and children consumers was equal to 9.73E-7 and 9.08E-7, respectively. Consequently, the concentration of toxic elements (Cd, Pb, and As) in cocoa powder did not pose any safety concerns. Moreover, probabilistic health risk assessment revealed that both adults and children were not at considerable non-carcinogenic (THQ and/or TTHQ ≤ 1) and carcinogenic risk (CR ≤ 1E-6). Even though, seeking for mitigating solutions and applying them to suppress the dangers of food containing toxic elements is a critical subject.

Integrative Evaluation of the Ecological Hazards by Microplastics and Heavy Metals in Wetland Ecosystem

This study was performed to evaluate the impact of microplastics and heavy metals (Pb, Cd, Cr, Cu, Zn, Ni) on sediments, water, aquatic plants (Pistia stratiotes, Alternanthera philoxeroides, and Ipomoea carnea), and fish (Labeo rohita) samples collected from five different sites in the Bajwat wetlands in Sialkot, Pakistan. The concentrations of Pb, Cd, and Cr were above the permissible limits devised by WHO in all the ecosystem components (i.e. sediments, water, plants, and fish) at all sites. The maximum amount of microplastic particles (2317 microplastic particles per kg of sediments) was recorded at Site 1. The filaments were the most commonly found type of microplastics. Plants and fish samples also showed considerable concentration of metals. The multivariate statistical analysis revealed anthropogenic sources of elevated concentrations of metal elements which could cause adverse biological effects in the ecosystem.

Spatial distribution and risk assessment of conazole fungicides in surface seawater of the East China Sea

Conazole fungicides (CFs), the common-used pesticide in agriculture distributed widely in the environment. This research analyzed the occurrence, potential sources, and risks of eight CFs in the East China Sea surface seawater in the early summer of 2020. The total CF concentration ranged from 0.30 to 6.20 ng/L, with an average value of 1.64 ± 1.24 ng/L. Fenbuconazole, hexaconazole, and triadimenol were the major CFs that comprised >96 % of the total concentration. The Yangtze River was identified as the significant source of CFs from the coastal regions to the off-shore inputs. Ocean current was the first-order factor controlling the content and distribution of CFs in the East China Sea. Although risk assessment revealed CFs posed a low or no substantial risk to ecology and human health, long-term monitoring was also encouraged. This study provided a theoretical foundation for assessing CFs' pollution levels and potential risks in the East China Sea.

The Content and Toxicological Risk Assessment of Trace Elemental Impurities (Pb and Cr) in Snacks from Ogun State, Southwestern Nigeria

The monitoring of food contamination by trace elemental impurities (TEIs) are major health challenges in developing countries. The present study evaluated the content and toxicological risk assessment of TEIs in commonly consumed snack/junk foods from Ogun State, Nigeria. TEIs (Pb and Cr) were determined in sixty snack food samples purchased from Ijebu Ode, Ogun State, southwestern Nigeria. The TEIs were analysed in quadruplicates using atomic absorption spectrometry with flame atomization. TEI data were subjected to simple descriptive and inferential statistics. The toxicological risk assessment of TEIs was evaluated for hazard quotient (HQ), hazard index (HI) and cancer risk (CR) using the United States Environmental Protection Agency-Integrated Risk Information System (USEPA-IRIS) model. Data showed the varying Pb levels of 8.22 ± 1.57 mg/kg in sausage to 12.25 ± 4.27 mg/kg in cocoyam chips higher than the permissible limit of the Codex Alimentarius of the Joint World Health Organization and Food and Agriculture Organization. The toxicological risk assessment revealed the HQs greater than 1.0 for Pb and Cr in most snack foods consumed by adults and children, indicating adverse health problems. The CRs of Pb (children) and Cr (adults and children) also breached the acceptable limit of 1.0 × 10^-4, signifying possible lifetime development of cancer. It is therefore necessary to periodically monitor the TEIs in snacks to protect the public health.

Pilot groundwater radon mapping and the assessment of health risk from heavy metals in drinking water of southwest, Nigeria

Radon and heavy metals are sources of groundwater pollution and are identified as potential carcinogens. Southwest Nigeria's populace mostly relies on groundwater source for drinking. This study aims to map radon distribution in groundwater of southwest Nigeria and to determine the health risk of radon and heavy metal in drinking water. Radon concentrations of 145 groundwater samples were measured using RAD7 electronic radon detector and heavy metal concentrations of 52 groundwater samples were measured using atomic absorption spectrophotometer. Radon concentration distributions were delineated using geographical information system. Radon concentration of water samples ranges between 1.6 Bq l⁻¹ and 271 Bq l⁻¹ with an average value of 35.9 ± 38.4 Bq l⁻¹. The average groundwater radon concentration is higher than US-EPA recommended level of 11.1 Bq l⁻¹ but lower than the WHO recommended limit of 100 Bq l⁻¹. The estimated average annual effective radiation doses to infants, children, and adults are 29 μSvy−1, 41 μSvy−1 and 92 μSvy−1 respectively. The radon distribution map of the study area reveals regions of high, medium, and low groundwater radon concentrations. The average concentration values of heavy metals in groundwater samples are of the order Mn > Zn > Pb > Cu > Cr > Ni > Cd. 84% of groundwater exhibits good to excellent quality in terms of heavy metal pollution. However, about 16% of the samples which lie in the sedimentary regions of Ogun and Lagos States exhibit poor to very poor quality. Overall, ingestion of groundwater in the study area may not pose a serious health hazards from radon ingestion and heavy metal toxicity.

Assessment of non-carcinogenic health risk of heavy metal pollution: evidences from coal mining region of eastern India

Various developmental projects and economic actions such as mining, industries, urban expansion, and agricultural activities contribute toxic heavy metals into the soils and it adversely affects to human health and broadly the environment. For the scientific study (coal mining region of Eastern India) around 120 soil samples were collected from top (0 - 20 cm) and subsurface soil (20 - 50 cm) of coal mining, semi mining and non mining type of land use sites to assess ten heavy metals applying standard methods and indices for the assessment of pollution load and human health risk. Statistical analysis clearly indicated that Fe, Mn, Zr are the most dominantly distributed in the study region. Coefficient of variance (CV)showed that there was very less variation in the metal values among samples of any particular landuse site. Correlation coefficient (0.05% level of significance) depicts that metals were very strongly correlated with each other in every site of Neturia block. Igeo (Geo- accumulation index) values of Fe and As indicated moderate to low pollution in the topsoil of study area. It is because of their regional background value. Enrichment Factor (EF) also showed thatcontamination of Fe ismainly supplied by natural factors (EF < 2)i.e., weathering of parent rock in all over the study area. All other heavy metals indicated their anthropogenic sources (EF > 2)on top and subsurface soil both of three landuse site. Degree of contamination (Cdeg), modified degree of contamination (mCdeg), contamination factor (CF) and pollution load index (PLI) clearly suggest that topsoil of coal mining sites is most polluted than two other sites. Subsurface soil of mining sites also indicated comparatively higher pollution load than subsoil of semi mining or non mining sites. PLI values have been classified into four groups i.e., high pollution (> 6), medium pollution (6 -3), low pollution (3 - 1) and no pollution (< 1) zone. There was no PLI value < 1 in topsoil of the study area. But subsurface soil of non mining site indicated no pollution to the soil. Spatial mapping using Inverse Distance Weightage (IDW) on Arc GIS 10.4 software showed clear variation of metal concentration and pollution load to the top and subsoil of the study area. Human health risk of non - carcinogenic typeisdue to heavy metals intake of topsoil through three exposure pathwaywhich indicates the health risk of HI _dermal> HI _ingestion> HI _inhalation for both the adult and children. Mean values of total HI showed that children are more prone to health risk in comparison with adult. There was no soil sample that exceeds its HI values > 1 for adults and thus no obvious health risk was found from soil heavy metals for adults.On the other hand, topsoil of mining sites indicated HI values >1;therefore, children are prone to health risk in this site. The present investigation suggests that coal mining region is highly polluted by their heavy metal burden on soil. Industrial and semi urban areas of semi mining region are also affected by heavy metal dust to its soil. Agricultural activities in non-mining region indicated lower pollution than other landuse sites. Remedial measures are highly needed to control heavy metal pollution of different landuse sites at colliery region to sustain environmental quality and human health as well. Modern scientific technologies and public awareness should be very useful on this way.

Oxidative stress-inducing effects of various urban PM2.5 road dust on human lung epithelial cells among 10 Chinese megacities

PM2.5 Road dust samples were collected from 10 representative cities in southern and northern China for examination of chemical components and oxidative stress levels in A549 cells. Downtown road dust was abundance of heavy metals, EC and PAHs compared to nondowntown road dust. Source apportionment also revealed the relative higher contribution of vehicle emission to downtown (35.8%) than nondowntown road dust (25.5%). Consequently, downtown road dust induced much higher intracellular reactive oxidative species (ROS) levels than that from nondowntown (p < 0.05). This study highlights that the ROS-inducing capacity of road dust in China is lower at lower latitudes, which resulted in a significantly higher ROS-inducing capacity of road dust from northern cities than southern ones. Hotspot analysis demonstrated that heavy metals (i.e., Cr, Zn, Cu and Pb) in road dust were the most closely associated with ROS production in A549 cells. Vehicle emission and combustion emission in road dust were identified to be correlated with cellular ROS production. The findings highlight the ROS-inducing effect of PM2.5 road dust and also serve as a reference to make the targeted solutions for urban road dust pollution control, especially from a public health perspective.

Assessment of quality and health risk of peri-urban groundwater supply from selected areas of Abeokuta, Ogun State, Southwestern Nigeria

Groundwater is an important source of drinking water. However, pollution of groundwater resource could initiate serious health damage to the consumers. The present study aimed at assessing the quality and health risk of groundwater samples collected from the peri-urban areas of Abeokuta. Twelve (12) fresh ditch cuttings from wells sites and forty (40) well water samples were collected between August and September, 2018. Samples were analysed for important physical and chemical parameters using the standard procedure. Groundwater data were subjected to statistical manipulation of descriptive and inferential statistics. The health risk assessment was conducted for non-carcinogenic effect {hazard quotient (HQ), hazard index (HI)} and cancer risk (CR). Results showed the pH of groundwater ranged from 7.65 to 8.48. The electrical conductivity varied from 266.5 to 461.5 µS/cm, while the total dissolved solids ranged from 90.0 to 348.2 mg/L. The concentrations of Pb (1.58-14.5 µg/L), Mn (11.10-836 µg/L), Al (64-2000 µg/L) and Fe (30-5070 µg/L) in groundwater were higher than the permissible limits of the World Health Organization in drinking water. The levels of metals/metalloids in the well cuttings were: Pb (8.9-27.6 µg/kg), As (0.8-8.6 µg/kg), Cr (14.0-98.0 µg/kg) and Mn (138.0-1080 µg/kg). The HQs of Cr (infants and children) and Ba (infants, children and adults) were greater than 1.0 indicating adverse health effects. The CRs of Cr, Co and Ni in water consumed by infants, children and adults were greater than the acceptable limit of 1.0 × 10^-4 suggesting possible development of cancer. The health risk data of metals in groundwater indicated deleterious health effects on consumers.

Health Risk Assessment of Metals in Selected Drinks from Abeokuta, Southwestern Nigeria

The present study assessed the human health risk of metals in selected drinks from Abeokuta, southwestern Nigeria. Fifteen different brands of drinks (alcoholic, non-alcoholic, herbal and non-herbal) were purchased from notable markets in Abeokuta between June and August, 2018. A total of sixty drink samples were analysed for metals using atomic absorption spectrophotometry. Data were subjected to descriptive and inferential statistics. Human health risks were assessed for cancer risk (CR) and non-carcinogenic indices of hazard quotient (HQ) and hazard index (HI). Results showed acidic medium for most of the samples ranging from 3.12 ± 0.29 to 6.14 ± 0.17. The highest concentrations of Fe (5.53 ± 2.81 mg/L) and Mn (6.63 ± 8.33 mg/L) were found in Kunnu and Zobo, respectively. The HQ and HI values of Cu in bottled water indicated non-carcinogenic adverse effects, while the CR of Co in bottled water and bitters demonstrated carcinogenic effects. Regular monitoring of metals in drinks from the study area is recommended.

Challenges Associated with Byproducts Valorization-Comparison Study of Safety Parameters of Ultrasonicated and Fermented Plant-Based Byproducts

In order to promote the efficient use of byproducts from the production of plant-based beverages, which still contain a large amount of nutritional and functional compounds, microbiological and chemical safety characteristics should be evaluated and, if needed, improved. Many challenges are associated with byproducts valorization, and the most important ones, which should be taken into account at the further steps of valorization, are biological and chemical safety. For safety improving, several technological treatments (biological, physical etc.) can be used. In this study, the influence of low-frequency ultrasonication (US) and fermentation with Lactobacillus casei LUHS210 strain, as physical and biotechnological treatments, on the safety characteristics of the byproducts (BYs) from the processing of rice, soy, almond, coconut, and oat drinks was compared. Ultrasonication, as well as fermentation, effectively improved the microbiological safety of BYs. Ultrasonication and fermentation reduced the concentration of deoxynivalenol, on average, by 24% only in soy BYs. After fermentation, 15-acetyldeoxynivalenol was formed in all samples (<12 µg kg-1), except for soy BYs. The lowest total biogenic amines content was found in fermented rice BYs and ultrasonicated coconut BYs. When comparing untreated and fermented BYs, significant changes in macro- and micro-elements content were found. Ultrasonication at 37 kHz did not significantly influence the concentrations of macro- and micro-elements, while fermentation affected most of the essential micro-elements. Consequently, while ultrasonication and fermentation can enhance the safety of BYs, the specific effects must be taken into account on biogenic amines, mycotoxins, and micro and macro elements.

Solidification and multi-cytotoxicity evaluation of thermally treated MSWI fly ash

Municipal solid waste incineration (MSWI) fly ash produced in waste-to-energy plants possesses a serious threat to human health. Although the traditional methods including toxicity characteristic leaching procedure and sequential extraction approach can partially evaluate the reduction of heavy metals leaching from thermally treated MSWI fly ash, the potential threat towards organisms is frequently ignored in previous literature. Considering this, herein we systematically assess the cytotoxicity of heat-treated samples using multiple cells from different biological tissues/organs for the first time. The results indicate that the leachability and transferability of heavy metals are declined after treatment. The biological assays demonstrate that the leachates from the treated residues induce lower phytotoxicity and cytotoxicity compared with the original samples. Moreover, according to the cellular responses of multiple cells to the leachates, normal cells (MC3T3-E1, HUVEC, and L929) are more tolerant to the leachates than cancerous cells (4T1, MG63), and the skin fibroblasts (L929), which often interact with the external circumstance, have the best cellular tolerance. This work provides a novel platform to determine the potential biosecurity of MSWI fly ash-derived products towards organisms, when they are served as secondary building materials in the constructional industry that may be contact with animals and human beings.

Metallic elements in human hair from residents in smelting districts in northeast China: Environmental factors and differences in ingestion media

The health of residents in Huludao City is affected by the emissions of heavy metals from smelting, diet and atmospheric precipitation. This study investigated the concentrations of Hg, Cd, Pb, Cu and Zn in scalp hair samples from 259 residents of different ages and genders from five districts in Huludao City and examined the main factors for heavy metal exposure. Cd and Pb concentrations in hair samples exceeded the normal concentration ranges for human hair (Cd < 0.3 mg/kg; Pb < 9.3 mg/kg), and the highest Pb concentrations were found in subjects in the age range 0-15 years. Samples from men were higher in Cd and Pb compared to those for women. Workers from the Huludao zinc plant (HZP) had higher concentrations of all metals in their hair relative to other occupations except for Cu. Geographically, the highest Cd and Pb concentrations in hair were found for residents living in Daochi district (DCD) and the Zn plant district (ZPD), respectively. In smelting regions, the effects of dust ingestion on heavy metal exposure were more important than in non-smelting regions.

Concentrations and Health Risk Assessment of Trace Elements in Cereals, Fruits, and Vegetables of Bangladesh

This study was conducted to determine concentrations of five toxic trace elements (Cr, Ni, As, Cd, and Pb) in cereals, fruits, and vegetables of Bangladesh. The range of mass fractions (mg/kg) of Cr, Ni, As, Cd, and Pb in the foodstuffs was 0.090-2.5, 0.03-2.6, 0.13-1.7, 0.010-0.74, and 0.37-2.2, respectively. This study indicates that concentration of Cr, and Pb in fruits; As, Cd, and Pb in vegetables were higher than WHO/FAO maximum allowable concentration levels. The hazard index (HI) values for adults and children of the toxic elements in studied cereals, fruits and vegetables were higher than 1.0, suggesting non-carcinogenic adverse health hazard to the consumers. The estimated target carcinogenic risk (TCR) values were greater than the threshold level of 1.0 × 10^-4 for Cr and Cd in cereals and vegetables indicate potential cancer risk to both adults and children for consumption of the foodstuffs. The present study reveals that trace elements contamination in foodstuffs is a serious issue of concern in Bangladesh.

A review of environmental and health effects of organochlorine pesticide residues in Africa

Organochlorine pesticides (OCPs) are generally categorized as chlorinated cyclodienes, chlorodiphenylethanes, chlorinated benzenes and cyclohexanes. The presence of OCP residues in foodstuffs, water, soil, sediments, blood serum and air has generated a surge of global interest. This is due to their severe environmental and health ill-effects. OCPs are characteristically described as persistent and bio-accumulating substances prone to long-range transportation. The aim of this present study is to assess the environmental and health risks associated with OCP residues. Published works on OCPs in surface water, sediments and fish samples were reviewed. Possible non-carcinogenic (Hazard Quotient, HQ and Hazard Index, HI) and carcinogenic (Cancer Risk, CR) health effects of OCPs were assessed in fish samples. High concentrations of OCP residues were determined in environmental samples from African countries. The non-carcinogenic health assessment of OCPs in most fish samples from Nigeria revealed HI values greater than 1.0 establishing their adverse effects. The CR data of OCPs in fish samples also showed values higher than the permissible standard of 1.0 × 10^-4 indicating possible development of cancer through fish consumption.

Evaluating the health risk of metals (Zn, Cr, Cd, Ni, Pb) in staple foods from Lagos and Ogun States, Southwestern Nigeria

The study evaluated the health risk of metals in commonly consumed staple foods from Lagos and Ogun states, southwestern Nigeria. One hundred and thirty-three food samples were collected and analyzed for Zn, Cr, Cd, Ni, and Pb using atomic absorption spectrophotometric method. Data collected were analyzed for simple descriptive and inferential statistics using SPSS for Windows. The health risk of metals in staple foods was assessed for average daily dose (ADD), hazard quotient (HQ), hazard index (HI), and cancer risk (CR). Results showed the highest concentrations of Zn (18.99 ± 13.62 mg kg^-1) and Ni (0.21 ± 0.10 mg kg^-1) in beans, while the highest amount of Cr (2.04 ± 1.44 mg kg^-1) was obtained in rice. Cd concentrations in staple foodstuffs ranged from < 0.01 to 0.30 mg kg^-1, while Pb was below the detection limit. The average levels of Zn in beans and maize were higher than the recommended dietary allowance (9.5 mg kg^-1) of the Institute of Medicine. The mean concentrations of Cr and Cd (except for rice) in staple food samples were also higher than the permissible standards. The health risk data revealed HQ value greater than 1.0 for Cr in the food samples, indicating non-carcinogenic adverse health effects. The HI value greater than 1.0 in staple foods established cumulative adverse effects of metals. The carcinogenic evaluation of Cr (in all the food samples) and Ni (in beans) showed CR values greater than the acceptable limit of 1.0 × 10^-4, thereby demonstrating possible development of cancer through consumption of the staple foodstuffs.