Mean Concentrations Of Pb Research Articles

Assessment of lead, cadmium, and mercury levels in the breast milk in Pakistani women.

The concentrations of potentially toxic metals like lead (Pb), cadmium (Cd), and mercury (Hg) in healthy lactating mothers of Lahore city were estimated during 2020-2021 with the help of a flame atomic absorption spectrometer (FAAS). Seventy samples of breast milk were collected from two different age groups, namely, G-1 (25-30 years) and G-2 (31-40 years). The results showed that Cd contents were below the detection limit of the measuring instrument; however, the Pb and Hg contents were detected with great ease. The mean concentrations of Pb and Hg in the G-1 corresponding to the age between 25 and 30 years were observed to be 1.914 ± 0.493 μg/L and 10.432 ± 3.249 μg/L, respectively. For the G-2 with an age limit between 31 and 40 years, the concentrations of Pb and Hg were estimated to be 2.045 ± 0.502 μg/L and 11.527 ± 3.231 μg/L, respectively. The T-test analysis of concentrations of these toxic metals indicated a significant correlation between the content levels of Pb and Hg (p < 0.05). The observed values of toxic metals were significantly more frequent than those suggested by WHO (World Health Organization). An increase in the concentrations of Pb and Hg is directly associated with the location of the target population. As a result, it is turned out that the majority of the lactating woman with significantly high levels of Pb and Hg belongs to industrial areas of Lahore. To avoid such conditions, residential areas must be at larger distances, in addition, to strictly abiding by the environmental policies of the government.

Lead and mercury in historical books and their contribution to dust contamination

Historical products are often a source of toxic substances, like heavy metals, that have since been restricted. In this study, the lead (Pb) and mercury (Hg) content of 133 books housed in two collections in southwest England (a university library and council repository), and published between 1704 and 2018, have been determined on-site by X-ray fluorescence spectrometry. Lead was detected in the front panels, text blocks and interior colour illustrations of most books, with maximum concentration of 15,100 mg kg-1, 8680 mg kg-1 and 12,800 mg kg-1, respectively. However, concentrations above 1000 mg kg-1 were generally restricted to books published between about 1850 and 1960. Mercury was detected in fewer cases, but concentrations above 5000 mg kg-1 were found in the red panels, coloured illustrations and red fore-edging of books published in the Victorian era. Mean concentrations of Pb in dusts from council repository shelves (112 mg kg-1) and library shelves (159–224 mg kg-1) and light casings (71.7 mg kg-1) were significantly higher than mean concentrations in household dusts from buildings constructed over the same period (24.8 mg kg-1). The findings suggest that historical books could be a source of Pb exposure where collections are housed or sold and could also be used to improve evaluations of historical indoor pollution.

Assessment of Heavy Metals in Potato and Onion Supplies in Rasht

Background: The entry of heavy metals into the food chain is an important environmental challenge for humans. Due to their potential for accumulating in the body, the different aspects of the hazard posed by heavy metals should be carefully examined. Objectives: The present study was conducted to determine the concentrations of heavy metals such as Arsenic (As), Cadmium (Cd), Chromium (Cr), Lead (Pb), and Nickel (Ni) in tuber crops i.e., potatoes and onions in Rasht, north of Iran. Materials &amp; Methods: A total of 140 potatoes and onions that were planted in difference cities of Iran were randomly procured from the city's fresh market in the spring during ten-day intervals. The acid digestion method was used for the preparation of the samples and the heavy metals were measured using an Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). Results: The mean concentration of Pb, Cd, Cr, and Ni found in the potato samples were 0.057, 0.079, 0.299, and 0.190 mg/kg of dry weight, respectively. The mean concentration of Pb, Cd, Cr, and Ni found in the onion samples were 0.067, 0.020, 0.275, and 0.235 mg/kg of dry weight, respectively. In both products, the amount of As was less than the device’s detection limit (1.187 ppb). The mean concentration of heavy metals in the products received from the northern region was higher than the central and southern parts of Iran. Conclusion: The results of this study showed that the mean concentration of Pb in both potatoes and onions were in the normal range. Similarly, the mean concentration of Cd, in onions was under the standard limit, but it was higher than the standard limit in some potato samples. Also, the mean concentration of Cr was higher than the standard limit.

Environmental and Health Impacts: Presence of Radionuclides and Toxic Metals in Mining Areas in Niger State, Nigeria

The distribution of radionuclides and heavy metals (carcinogenic and non-carcinogenic) in soil and plants grown in lead contaminated areas were determined using gamma spectrometry and AAS (Atomic Absorption Spectrometry). The values of Dout (outdoor dose rate) and Din (indoor dose rate) were found to vary from 49.10 to 96.59 nGy h-1 with a mean value of 73.75 nGy h-1 and 97.30 to 191.67 nGy h-1 with a mean value of 143.39 nGy h-1 for Kawo; 51.64 to 105.26 nGy h-1 with a mean value of 75.36 nGy h-1 and 104.43 to 205. 87 nGy h-1 with a mean value of 157.13 nGy h-1 for Magiro. The weighted mean concentrations of Pb, Cu, Fe, Cr, Cd and Ni in mg kg-1 in soil and crop were (2.20,2.29), (3.14, 0.16), (15.10, 19.33), (0.16, 0.25), (0.24, 0.05), (0.43, 0.06) and (3.00, 3.18), (6.09, 0.34), (16.83, 10.10), (0.22,0.36), (0.25, 0.05), (0.43, 0.06) for Kawo and Magiro respectively. The total incremental lifetime cancer risk ΣILCR for both adults (0.73 x 10-2) and children (1.03 x 10-2) were above tolerable acceptable risk (given as 1 x 10-6 to 1 x 10-4). Therefore, the areas need remedial action and proper monitoring.

Spatial Distribution of Lead in the Soil of Urban Areas Under Different Land-Use Types

Awareness of lead (Pb) distribution and zoning in urban, agricultural, and industrial areas is of particular importance in environmental protection planning. This cross-sectional study aimed to determine the distribution of Pb in different uses with different levels of industrial development and human activities in urban areas in Hamadan during 2018. For this purpose, 146 soil samples were collected from 0-20 cm depth and prepared for air-dried laboratory analyses. Then, pH, electrical conductivity (EC), total Pb, and adsorbable Pb in the soil were measured. The results demonstrated that the mean concentration of total Pb is 88 mg/kg. In addition, the mean concentration of Pb in urban, industrial, and agricultural areas was 41 mg/kg, 30 mg/kg, and 17 mg/kg, respectively. Further, the average concentration of adsorbable Pb with a standard deviation of 0.3 in industrial, urban, and agricultural areas was 0.38 mg/kg, 0.16 mg/kg, and 0.06 mg/kg. Land use was an important source of Pb change in the studied soils; however, Pb change did not depend only on land use. Factors such as weather conditions or proximity to roads, as well as previous land uses, could affect the role of existing land use and be effective in the distribution of soil Pb. Studies revealed that the amount of the soil’s adsorbable Pb is more important than that of total Pb in different uses, which should be considered in any soil-related research.

ACCUMULATION OF HEAVY METALS IN CELERY PLANT APIUM GRAVEOLENS AND SOIL IRRIGATED WITH WASTEWATER WITHIN DUHOK CITY KURDISTAN OF IRAQ

Wastewater contains poisonous metals which can be moved and accumulated in plants before entering the human body through the food chain. The aim of this research was to investigate the concentrations of toxic metals such as Nickel (Ni), lead (Pb), and copper (Cu) in wastewater, celery plant and farmlands soils of Duhok city Kurdistan of, Iraq. The heavy metals accumulation in the Celery plants, soil and water samples were analyzed by using an atomic absorption spectrophotometer. The results obtained showed that the mean concentrations of Pb, Ni, and Cu in the wastewater and Celery plants samples ranged from 0.45±0.08 to 5.95±0.2, 0.18±0.01 to 1.95±0.28, 0.02± 0.01 to1.13±0.23 mg/L respectively. The pattern of metal buildup in wastewater-irrigated soil is in the order: Cu &gt; Pb &gt; Ni, and the mean concentration of Pb, Ni and Cu in soil ranged between 21.68±0.42 to 118.57±0.07, 1.27±0.47 to 5.70±0.23, 1.28±0.24 to ± 15.12 0.53 mg/kg-1, respectively. While the mean concentration of Pb, Ni and Cu in celery leaves ranged from 1.04±0.22 to 5.22±0.60, 0.52± 0.22 to 4.31± 0.12, respectively. 1.34 ±0.22 to 19.47±0.82, 1.23±0.04 to 7.29± 2.53, 1.01±0.05 to 5.76±1.32 mg/ kg-1, respectively. According to this study, roots contain more heavy metals than leaves. According to the findings, a few of the sampling sites had Pb, Ni, and Cu values that were exceeded the permissible concentration. Celery plants cannot be planted in the Duhok Valley to prevent excessive heavy metal exposure to human health through vegetables, where the main irrigated water source is sewage from the local municipalities. Celery plant irrigation with wastewater has much greater levels of heavy metals than the controls.

Health Risk Assessment of Lead, Cadmium, and Arsenic in Leafy Vegetables in Tehran, Iran: the Concentration Data Study.

Absorption of heavy and toxic metals causes their accumulation in the edible parts of vegetables. Pollutants such as heavy metals have directly affected the health of society and contributed to emerging diseases in recent years. The current study aimed to detect heavy metals (Pb, Cd, As) in highly consumed leafy vegetables provided from the Tehran market. Four types of vegetables, including dill, parsley, cress, and coriander were selected and 64 samples were randomly collected from fruit and vegetable markets in different regions of Tehran in August and September 2022. Then, samples were analyzed by the ICP-OES system, and health risk assessment was conducted using non-carcinogenic and carcinogenic approach. The range of Pb concentration was 54-314, < LOQ-289, < LOQ-230, and < LOQ-183μg/kg for dill, cress, parsley, and coriander, respectively. The high mean concentrations of Pb belong to the dill (161.43 ± 77.3μg/kg) and cress (154.75 ± 72.9μg/kg). In some samples of dill (37.5% of samples), cress (18.75% of samples), and parsley (12.5% of samples), the Pb content was above the national allowable limit (200μg/kg). The range of Cd concentration was < LOQ-42, < LOQ-41, < LOQ-30, and < LOQ-38μg/kg for dill, cress, parsley, and coriander, respectively. In none of the samples, the concentration of Cd was higher than the Iranian national limit (50μg/kg). The As occurrence was observed in all cress samples with a mean of 165.19 ± 64.83μg/kg. The range of As concentration was < LOQ-71, < LOQ-256, 58-273, and < LOQ-75μg/kg for parsley, dill, cress, and coriander, respectively. The THQ and HI values were higher than 1, and either ILCR value was higher than 10-4 for all tested heavy metals, it can be concluded that higher levels of heavy metals than the standard limits in some samples may raise the warning alarm and should come to the attention of the authorities.

Levels of heavy metal in soil and vegetable and associated health risk in peri-urban areas across China

Peri-urban vegetable field plays an essential role in providing vegetables for local residents. Because of its particularity, it is affected by both industrial and agricultural activities which have led to the accumulations of heavy metal in soil. So far, information on heavy metal pollution status, spatial features, and human health risks in peri-urban vegetable areas across China is still scarce. To fill this gap, we systematically compiled soil and vegetable data collected from 123 articles published between 2010 and 2022 at a national level. The pollution status of heavy metals (i.e., cadmium (Cd), mercury (Hg), arsenic (As), lead (Pb), chromium (Cr), copper (Cu), nickel (Ni), and zinc (Zn)) in peri-urban vegetable soils and vegetables were investigated. To evaluate the levels of heavy metal pollution in soil and human health risks, the geoaccumulation index (Igeo) and target hazard quotient (HQ) were calculated. The results showed that mean concentrations of Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn in peri-urban vegetable soils were 0.50, 0.53, 12.03, 41.97, 55.56, 37.69, 28.55, and 75.38 mg kg−1, respectively. The main pollutants in peri-urban vegetable soil were Cd and Hg, and 85.25% and 92.86% of the soil samples had Igeo > 1, respectively. The mean Igeo values of this regions followed the order of northwest > central > south > north > east > southwest > northeast for Cd and northeast > northwest > north > southwest > east > central > south for Hg. The mean Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn concentrations in vegetables were 0.30, 0.26, 0.37, 0.54, 1.17, 6.17, 1.96, and 18.56 mg kg−1, respectively. Approximately 87.01% (Cd), 71.43% (Hg), 20% (As), 65.15% (Pb), 27.08% (Cr) of the vegetable samples exceeded the safety requirement values. The vegetables grown in central, northwest, and northern China accumulated much more heavy metals than those grown in other regions. As the HQ values for adults, 53.25% (Cd), 71.43% (Hg), 84.00% (As), and 58.33% (Cr) of the sampled vegetables were higher than 1. For children, the HQ values were higher than 1 for 66.23% (Cd), 73.81% (Hg), 86.00% (As), and 87.50% (Cr) of the sampled vegetables. The findings of this study demonstrate that the situation of heavy metal pollution in peri-urban vegetable areas across China are not optimistic and residents who consume the vegetables are at high risk of health issues. To ensure soil quality and human health, strategies should be taken to guide vegetable production and remedy soil pollution in peri-urban areas with the rapidly urbanizing China.

Heavy Metal Concentration and Human Health Risk Assessment of Selected Brands of Seasoning Powder Sold in Port Harcourt, Nigeria

Seasoning powders are frequently used to enhance the taste, aroma, color and overall acceptability of food by consumers. Different brands of seasoning powder are frequently consumed without adequate human health risk assessment of the heavy metals constituents in them. This study was conducted to determine the heavy metal concentration in four (4) brands of seasoning powder (SP1, SP2, SP3 and SP4) sold in Port Harcourt, Nigeria. Ten (10) heavy metals (As, Cr, Ni, Pb, Cd, Fe, Co, Cu, Mn and V) were analyzed by standard methods using Flame Atomic Absorption Spectrophotometer (Model: GBC 908PBMT). Human Health Risk Assessment of heavy metals in the seasoning powders, taken in through ingestion route, was evaluated by computing the Estimated Daily Intake (EDI), Hazard Quotient (HQ), Hazard Index (HI) and Cancer Risk (CR) based on adult human model variables provided by United States Environmental Protection Agency (USEPA). The results showed that mean concentration of Pb and Cd were 6.35 ± 1.07 mg/kg and 0.53 ± 0.09 mg/kg respectively which are above the Food and Agricultural Organization (FAO) and World Health Organization (WHO) Maximum Permissible Limit (MPL) of 5.0 mg/kg and 0.3 mg/kg respectively. Concentration of Fe, Co, Cu, Mn, and V were below the MPL and As and Cr were not detected in all the samples assessed.EDI for the measured heavy metals were less than the tolerable limits specified by USEPA. The HQ and HI values were within acceptable range of &lt;1 except for SP2 with HI value of 1.04. The results obtained for CR were above the specified acceptable range of 1.0 x10-6 to1.0 x 10-4. These results suggest possible health concerns associated with the consumption of these seasoning powders in the long term. Strict and systematic surveillance of heavy metals such as Pb and Cd in commonly consumed seasoning powder should be done to ensure safety and quality of the seasoning powders sold in Nigeria. Keywords: Seasoning powder, Heavy metals, Bio-toxicity, Hazard index, Cancer risk.

Risk assessment of combined exposure to lead, cadmium, and total mercury among the elderly in Shanghai, China

Lead (Pb), cadmium (Cd) and total mercury (THg) are toxic heavy metals (THMs) that are widely present in the environment and can cause substantial health problems. However, previous risk assessment studies have rarely focused on the elderly population and have usually targeted a single heavy metal, which might underestimate the long-term accumulative and synergistic effects of THMs in humans. Based on the food frequency questionnaire and inductively coupled plasma mass spectrometry, this study assessed external and internal exposures to Pb, Cd and THg in 1747 elderly people in Shanghai. Probabilistic risk assessment with the relative potential factor (RPF) model was used to assess the neurotoxicity and nephrotoxicity risks of combined THMs exposures. The mean external exposures of Pb, Cd and THg in Shanghai elderly were 46.8, 27.2 and 4.9 μg/day, respectively. Plant-based foods are the main source of Pb and THg exposure, while Cd is mainly from animal-based foods. The mean concentrations of Pb, Cd and THg were 23.3, 1.1 and 2.3 μg/L in the whole blood, and 6.2, 1.0 and 2.0 μg/L in the morning urine, respectively. Combined exposure to THMs leading to 10.0 % and 7.1 % of Shanghai elderly at risk of neurotoxicity and nephrotoxicity. The results of this study have important implications for understanding the profiles of Pb, Cd and THg exposure in the elderly living in Shanghai and provide data support for risk assessment and control of nephrotoxicity and neurotoxicity from combined THMs exposure in the elderly.

The Concentration and Risk Assessment of Potentially Toxic Elements (PTEs) in Farmed and Wild Carps (Cyprinus carpio) in Hamadan Province of Iran.

This study focuses on measuring potentially toxic elements (PTEs) including mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), iron (Fe), copper (Cu), zinc (Zn), manganese (Mn) in farmed and wild carp by inductively coupled plasma-optical emission spectrometry (ICP-OES) and their intake amount and risk assessment. Estimated Daily Intake (EDI), Target Hazard Quotient (THQ) and the total THQ (TTHQ) were calculated for each element. In the present research, the concentration of As in farmed and wild carp samples was below the detection limit of ICP-OES (< 0.005mg/kg). The mean concentrations of Pb, Cd, Fe, and Cu in farmed carp samples were significantly higher than that in wild carp samples, while Zn level was higher in the wild carp samples (P < 0.05). There is no significant difference between Hg and Mn in both fish (P > 0.05). The Monte Carlo simulation (MCS) results showed that the ranking order of PTEs based on their THQ was Hg > Pb > Zn > Cu > Fe > Cd > Mn. In the worst-case scenario (in the top 95 percentile) for both wild and farmed carp, the THQ of measured metals was less than one except Hg in children. Overall, this study demonstrated that the levels of PTEs in farmed and wild common carp had a potential non-carcinogenic risk for children (TTHQ > 1).

Human exposure to dust and heavy metals in industrial regions and its relationship with the prevalence of multiple sclerosis disease.

In recent decades, multiple sclerosis (MS) diseases have been significantly prevalent in some industrial areas of Iran, such as steel industrial areas in Isfahan province (central Iran). In this study, the environmental impacts of two steel mill factories in Isfahan province and their effects on the spread of MS in the region were investigated. To examine the extent of exposure, seasonal dust samples were collected from 15 sites around the two investigated factories. The annual dust deposition rate (DDR) was then determined and the concentrations of lead (Pb), cadmium (Cd), nickel (Ni), cobalt (Co), and manganese (Mn) in the dust samples were measured. Furthermore, the concentration of the mentioned elements was determined in the nail samples taken from 40 MS patients and 40 healthy people (control) living in the study region. The interpolated map extracted from the DDR values showed the highest dust deposition around the two studied steel factories, which decreases with increasing distance from them. The enrichment factor (EF) of heavy metals was the highest at the distance between the two steel factories, decreasing by moving away from them which indicate that these two steel factories are the source of investigated heavy metals in the region. The statistical analysis also revealed significant differences (P < 0.01) between the concentration of heavy metals measured in nail samples taken from MS patients and healthy people. The mean Pb concentration measured in the nail sample taken from MS patients was more than 18 times that of healthy people (93.45 and 5.02mg/kg, respectively). These results revealed a buildup of heavy metals in the body of MS patients much more than usual, originating from the activities of two investigated steel companies in the region.

Decline of anthropogenic lead in South Atlantic Ocean surface waters from 1990 to 2011: New constraints from concentration and isotope data

Anthropogenic emissions have severely perturbed the marine biogeochemical cycle of lead (Pb). Here, we present new Pb concentration and isotope data for surface seawater from GEOTRACES section GA02, sampled in the western South Atlantic in 2011. The South Atlantic is divided into three hydrographic zones: equatorial (0–20°S), subtropical (20–40°S), and subantarctic (40–60°S). The equatorial zone is dominated by previously deposited Pb transported by surface currents. The subtropical zone largely reflects anthropogenic Pb emissions from South America, whilst the subantarctic zone presents a mixture of South American anthropogenic Pb and natural Pb from Patagonian dust. The mean Pb concentration of 16.7 ± 3.8 pmol/kg is 34 % lower than in the 1990s, mostly driven by changes in the subtropical zone, with the fraction of natural Pb increasing from 24 % to 36 % between 1996 and 2011. Although anthropogenic Pb remains predominant, these findings demonstrate the effectiveness of policies that banned leaded gasoline.

Performance of castor in heavy metal polluted soils under the treatment of various decontaminants

In order to find out the performance of castor under decontaminant treated heavy metal polluted soils, an experiment was conducted at Students Farm, College of Agriculture, PJTSAU, Rajendranagar, Hyderabad, during kharif 2016 to study the performance of castor in heavy metal polluted soil under the treatments of various decontaminants (various dosages of phosphorus as well as, quick lime). The dry matter before flowering, and stalk yield at harvest of castor varied from 429 to 516, 1460 to 1758 kg/ha, respectively. Among the different decontaminants highest dry matter yield and stalk yield (516 and 1758 kg/ha at before flowering and harvest) and seed yield (1720 kg/ha) was obtained in T5 (RDF+CaO @ 2 t/ha), which was significantly superior over all other treatments and on par with T4 (RDF+CaO @ 1 t/ha), and per cent increase over RDF was 20.41 and 23.56, respectively for stalk, and seed yield of castor. Decontamination treatments had reduced the mean Pb, Cd, Ni and Co contents of castor to 4.51, 0.65, 0.95 and 0.63 mg/kg, and increased mean uptake to 7.62, 1.17, 1.69 and1.09 g/ha respectively, for Pb, Cd, Ni and Co in seed at harvest. The Pb, Cd, Ni and Co contents of soil after harvest of the castor crop ranged from 17.11, 0.79, 1.89 and 1.22 mg/kg in the reference control and decreased to 14.60, 0.68, 1.67 and1.02 with RDF+CaO @ 2 t/ha treatment. The reduction in Pb, Cd, Ni and Co concentration in post-harvest soil was more due to Cao at different levels when compared to high phosphorus.

Persistence of trace metal contamination in a fluvial system: Lahn River, central Germany

To monitor short-term changes in trace metal concentrations (Cu, Pb, Zn) at geomorphically sensitive floodplain locations and examine the persistence of contaminants in the fluvial environment, near-channel sites along the Lahn River, central Germany, that were sampled in 2007 were revisited in 2019. Thirty-three cores were extracted from sites <5 m from the active channel along a 75-km reach of the river. The median concentrations of Cu and Zn in 2019 were statistically unchanged from concentrations in 2007, but median concentrations of Pb in 2019 were statistically higher than in 2007. Concentration of all three trace metals remain above the background concentrations, but only Zn concentrations exceed the 2ϭ background upper limit. On an individual sample site basis, the Cu concentration increased at 48 % of the sites and the Zn concentration increased at 45 % of the sites between 2007 and 2019. Pb concentration increased at 70 % of the sites. Concentrations of trace metals generally increased with distance downstream; the lowermost reach of the Lahn River continues to have the highest concentration of trace metals. Between 2007 and 2019, the concentrations (mean and median) of all three metals increased in the uppermost and lowermost sections of the study area whereas in the middle section the mean and median concentrations of Cu and Zn and the median concentration of Pb decreased (the mean concentration of Pb increased in the middle reach). Changes in metal concentrations between 2007 and 2019 do not appear to be caused by factors such as changes in substrate of samples, variable sedimentation rates and flood history, or the percentage of clay and organic matter content. Elevated concentrations of trace metals persist in near-channel sediments and will continue to pose a risk of future downstream heavy metal pollution in the study reach, especially along the lowermost reach of the Lahn River where the most contaminated sediments are located. Trace metal concentrations in the study reach appear to have become “uncoupled” from overall decreases in metal releases to the environment.

Lead Exposure of Four Biologically Important Common Branded and Non-branded Spices: Relative Analysis and Health Implication.

Technological advances and socioeconomic development of Bangladesh are leading to the best choice between branded and non-branded powdered spices. But toxic metal issues can be another factor to elect them. So lead (Pb) exposure and its consequence on the human body for these two categories of four common spices have been ascertained here. A validated laboratory method using hot plate digestion and flame atomic absorption spectrometry (FAAS) has been used for that. The obtained mean concentration of Pb in branded and non-branded spice powders followed the decreasing order of turmeric > coriander > red chili > cumin powder and turmeric > red chili > cumin > coriander powder, respectively, where, in any analysis mode, the non-branded items are potentially ahead of Pb exposure. The market-based mean concentration between these two categories was not a significant difference (t-test). Approximately 90% of the spice samples have shown within the maximum allowable limit by Bangladesh Standard. The sum of estimated daily intake indicated that most of the city market (67%) for non-branded items and some branded (33%) samples have crossed the maximum tolerable daily intake (> 0.21mg/kg). So, the human health risk assumption for the inhabitant of studied areas suggests there is no significant level of risk for them due to the consumption of spices regarding non-carcinogenic risk factor (THQ and total THQ) and carcinogenic risk factor (CR). But the development of a quality control process for loose spice powders as well as toxic metal screening from raw materials to finish products urgently needed and continuous monitoring with identifying the source of toxic metal is highly recommended.

Health risk assessment of heavy metals in drinking water from Iponri water treatment plant, Lagos water corporation Nigeria

Abstract Urban water supplied from treatment plants can constitute public health problems if poorly treated or accidentally contaminated. Water quality and health risk assessment of water supplied from Lagos State water treatment plant was performed. Heavy metal concentration was determined using Atomic Absorption Spectrophotometer. The mean concentrations of Pb, Cu, Zn, Fe, Mn, Cd, Ni, As and Cr were within the standard maximum permissible limits for drinking water quality. The mean estimated daily intake through oral ingestion of drinking water for Pb, Cu, Zn, Fe, Mn, Cd, Ni, As and Cr were 0.00024, 0.00117, 0.00158, 0.00665, 0.00736, 0.000271, 0.00148, 0.000563 and 0.000834 mg/kg bw/day respectively, but were within acceptable tolerable daily intake standards for adult population. The values of hazard quotients for the heavy metal in water samples were below one for adult population. Hazard indices of treated water samples were below the threshold value of one (HI ˂ 1) while hazard indices of untreated and pre-treated water samples exceeded one, indicating possible associated potential health risks as a result of combined effects of the heavy metals through oral consumption water. Incremental life cancer risk values of Cd, Ni, As and Cr in all the three categories of water samples exceeded the safe limit for cancer risk while the cumulative cancer risk (ΣILCR) also exceeded the proposed threshold safe risk limit (&gt; 1x10−4), indicating potential carcinogenic lifetime health risk in adult population through oral consumption of the heavy metal in water. Conclusively, the treated water had lowest levels of heavy metals, hazard quotient, incremental life cancer risks values and unsafe for drinking purposes compared to the untreated and pre-treated water.

Determination of Heavy Metals in Green Leafy Vegetables along Roadsides by Lagos-Badagry Expressway in Lagos, Nigeria

Heavy metals being natural components of the earth’s crust, cannot be degraded or destroyed. They are ubiquitous, so enter the human body through food, water and air, which in high concentrations in biological systems result in human diseases and disorders. Vegetable samples which included leaves of lettuce, spinach and pumpkin were collected from three wayside farms namely; Abule Ado, Abule Oshun and Oluti. A total of 36 samples were collected for the assessment of the heavy metal contents in the vegetables, which included lead (Pb), Zinc (Zn), Cadmium (Cd) and Chromium (Cr) using Flame Atomic Absorption Spectrophotometer (Buck Scientific 210 VGP model) in mg/kg. The average concentration of Pb, Zn, Cd and Cr in lettuce were 29.70, 25.85, 1.6 and 16.54 respectively. The mean concentration of Pb, Zn, Cd and Cr in spinach leaves were 28.84, 38. 43, 0.66 and 19.57 while the average concentration of Pb, Zn, Cd and Cr in pumpkin were 22.98, 38. 70, 0.70 and 29.70 mg/kg respectively. Lettuce had the highest concentration of Pb, while pumpkin had the least Pb concentration. Pumpkin had the highest concentration of Zn, followed by spinach, and the least concentration in lettuce. Lettuce had the highest concentration of Cd, followed by pumpkin and spinach with the least concentration of Cd. The highest concentration of Cr was observed in spinach, followed by lettuce, while pumpkin had the least Cr concentration. This study revealed that the concentrations of Pb, Zn, and Cd were within acceptable limits according to WHO, while Cr was found above that limit. If ingested, the heavy metals result in bioaccumulation and biomagnification, which as well lead to human disorders with children at higher risks than adults.

Heavy Metals and Total Hydrocarbon Contents of Nypa fruticans Grown along the Shores of Qua Iboe River, Akwa Ibom State of Nigeria

This study ascertains the amount of heavy metal and hydrocarbon content in an area exposed to crude oil exploration and exploitation activities. The study area is the Qua Iboe River in the Niger Delta region of Nigeria and the study samples were Nypa palm (Nypa fruticans) leaves obtained along the shores of the river. The concentration of Pb, Cd, Cu and Ni in the leaves were determined using the Atomic Absorption Spectrophotometer while Total Hydrocarbon Content was determined using Gas Chromatography, coupled with the flame ionization detector (GC-FID). Results obtained showed that in site I, Pb mean concentration was 1.068±0.014 mg/kg, Cd (0.017±0.003 mg/kg), Cu (2.390±0.204 mg/kg), Ni (0.012±0.001 mg/kg) and THC (124.361.7± 1120.502 mg/kg) while for site II: Pb (1.076±0.025 mg/kg), Cd (0.028±0.003 mg/kg) Cu (0.037±0.007 mg/kg) Ni (2.049±0.024 mg/kg) and THC (311,813.4± 2950.291 mg/kg). Heavy metal concentration in the study sites were largely within the WHO permissible limits with the exception of Cd in site II. Generally, the amount of heavy metals and THC were higher in the study sites than in the control site, which was an area with negligent oil exploitation and industrial activities. Therefore, the elevated concentration of heavy metals and THC in the study sites may be attributed to the various industrial activities sited in the area.

Lead in painted surfaces and dusts from rented urban properties (Plymouth, UK)

X-ray fluorescence (XRF) spectrometry has been used to measure lead (Pb) in painted surfaces and indoor dusts from 14 rented properties in the city of Plymouth, UK. Lead was detected in 78 out of 164 surfaces measured (and in 69 out of 150 interior surfaces) with an overall median concentration of 7100 mg kg−1 (range from 157 to 139,000 mg kg−1), and was detected in all but two properties that included one building constructed within the last 25 years. Selected measurements on an area basis (n = 48) returned Pb concentrations ranging from below 0.01 to 16.1 mg cm−2 that were significantly correlated with concentrations on a mass basis but with scatter that was attributed to the degree to which leaded paint had been overpainted. As potential measures of Pb exposure, mean concentrations in samples of lint (n = 8) were <15 mg kg−1 while mean concentrations in hoovered dusts (n = 14) were more variable; specifically, mean Pb dust concentrations ranged from ∼20 to 140 mg kg−1 in 13 samples but was ∼4500 mg kg−1 in a property that had recently undergone extensive renovation. Although mean concentrations of Pb in lint or dust were not related to median Pb concentrations in paint, a strong correlation between barium (Ba) and Pb in dusts suggests that paint is the main source of dust Pb. This study indicates that, in most cases, leaded paints historically applied to interior surfaces have been over-coated and pose little risk, provided that surface coatings are in good condition. However, inappropriate practices during renovation can result in significant contamination of dusts. Our findings are likely to be more broadly applicable to the urban rented sector in the UK and landlords and tenants should, therefore, be made aware of government guidance on the safe decoration or remodelling of older properties where leaded paint is pervasive.