Health Risk Assessment Of Metals Research Articles

Heavy metals health risk assessment through consumption of some foodstuffs marketed in city of Hamedan, Iran.

Since global studies on the health risk assessment of heavy metals in foodstuffs, including biscuits, potato chips, chocolates, and traditional pastries are limited, hence, this study was conducted to determine the contents and the human health risk assessment of lead (Pb), cadmium (Cd) and chromium (Cr) via the consumption of different brands of these foodstuffs.In this descriptive study, a total of 84 samples of 28 brands/kinds of food under consideration were collected from a market basket in city of Hamedan, Iran in 2016. After preparation and processing the samples in the laboratory, the metal concentrations were measured using the inductively coupled plasma-optical emission spectrometer (ICP-OES). In addition, all statistical analyses including One-Way ANOVA and one-sample t test were performed using the SPSS statistical package (Version 19). The results showed that the mean concentrations (mg kg-1) of Pb in all the foodstuff samples (2.25 ± 0.76 for biscuits, 1.60 ± 0.35 for potato chips, 2.61 ± 0.68 for chocolates, and 3.66 ± 0.64 for traditional pastries) were higher than the Maximum Permissible Limit (MPL).Furthermore, the computed health risk index showed no potential risk for adults and children via consumption of the studied foodstuffs under the current consumption rate.Based on the results, as the mean contents of Pb observed in all the foodstuff samples exceeded the MPL, serious attention toward the discharge of pollutants into the environment and chemical residue monitoring, especially of heavy metals in foodstuffs, is recommended.

Metal(loid)s urinary level among workers of gas refinery and petrochemical companies: Health risk assessment of metal(loid)s in drinking water and dust

BackgroundAsalouyeh (southern Iran) contains many pollution sources like petrochemical and gas refinery companies. Few studies were conducted on the body burden of metal(loid)s in occupationally exposed workers of the companies in this area. ObjectivesThe urine concentration of metal(loid)s in workers of gas refinery and petrochemical companies in Asalouyeh (who have been worked as "two weeks work-two weeks rest" schedule) was evaluated during a before-and-after observational study. The risks of metal(loid)s in drinking water and dust particles in the studied area were also assessed. MethodsUrinary samples (n = 179) were gathered at the first day of two weeks of work (before) and at the end of two weeks of work (after). The concentration of V, Ni, Mn, Cd, and As was measured using a graphite furnace atomic absorption spectrometry. The health hazards of metal(loid)s in the air dust and drinking water of workers were also evaluated. ResultsThe median concentration of metal(loid)s for workers of gas refinery and petrochemical companies for before and after two weeks of work was measured, respectively, as: As (11.44 and 9.31 μg/L), Ni (1.06 and 0.51 μg/L), Cd (0.36 and 0.31 μg/L), Mn (0.29 and 0.24 μg/L), and V (0.08 and 0.05 μg/L). After two weeks work, the median of all metal(loid)s in the urine of petrochemical and gas refinery workers was significantly increased. The non-cancer risk due to intake metal(loid)s from drinking water was more than the threshold value and the cancer risk from drinking water and inhaled air dust was less than the threshold. ConclusionOur results revealed the effect of gas refinery and petrochemical activities on increasing the metal(loid)s concentration of the worker's body and the necessity to protect this group. Additionally, the metal(loid)s intake from drinking water and inhaled dust posed no cancer risk to the workers.

Monte Carlo simulation-based probabilistic health risk assessment of metals in groundwater via ingestion pathway in the mining areas of Singhbhum copper belt, India

ABSTRACT Probabilistic health risk assessment was conducted for metal exposure through groundwater in mining areas of Singhbhum Copper Belt, India. The concentrations of metals showed notable spatial variation exceeding drinking water standards at some of the locations. Hazard Quotient revealed that chronic risks to the local population were largely contributed by Mn, Co and As. The 95th percentiles of Hazard Index (HI) calculated using Monte Carlo simulations showed that the HI for male, female and child populations was 2.87, 2.54 and 4.57 for pre-monsoon, 2.16, 1.88 and 3.49 for monsoon and 2.28, 2.02 and 3.75 for post-monsoon seasons, respectively. The Hazard Indices indicated that amongst the populations, risk was greater for child population and considering the seasons the risk was higher during the pre-monsoon season. The sensitivity analysis suggested that concentration of metals in groundwater and exposure duration were 2 most influential input variables that contributed to the total risk.

Quality and Human Health Risk Assessment of Metals and Nitrogen Compounds in Drinking Water from an Urban Area Near a Former Non-Ferrous Ore Smelter

The quality and potential health risk of drinking waters in Medias, a town near a former non-ferrous ore smelter in Romania, was assessed using the drinking water quality index (DWQI), hazard quotient (HQ) and total hazard quotient (THQ). A total of 29 water samples collected from 26 wells and 3 springs used as drinking water sources, located in near proximity to agricultural, industrial or household contamination sources, were characterized. The obtained results indicated high NO2−, NO3−, Cd and Mn levels that exceeded the corresponding maximum allowable concentrations. According to the DWQI values, only 10% of water sources have acceptable quality, while 21% are threatened, and 69% have poor- quality. The health risk assessment suggested a high risk for NO3− for more than 72% of the drinking waters HQNO3− > 1.0 but no risk for metals and NO2− (HQmetals< 1.0; HQNO2−< 1.0).

Risk Assessment of Certain Heavy Metals and Trace Elements in Milk and Milk Products Consumed in Aswan Province.

Considering that pollutants transformed to human body through food consumption, food safety is of great concern to consumers. Because consumption of milk contaminated with heavy metals poses serious threats to consumer's health. This study was conducted to evaluate the concentration of heavy metals and its risk with the consumption of milk and milk products in Aswan Province . A total of 20 samples of raw fresh buffalo, cow, sheep and goat milk and 16 samples of milk products of Kareish cheese, Domiati cheese, Mish and Samna were analyzed for the presence of heavy metals of Cadmium (Cd) and Lead (Pb) and trace elements of Copper (Cu) and Zinc (Zn) via Atomic Adsorption Spectrophotometer (AAS). The results showed that the concentration of total heavy metals differed between different areas, it was the highest in Edfu but the least in Toshka. With the analysis of metals concentration in milk of different species, the results showed higher concentration of total metals in sheep and goat milk combined with low content of Cd and high content of Zn and Cu than that of cow and buffalo milk. Comparing the Cd, Pb, Cu and Zn concentrations in locally manufactured milk products with the permissible upper limit of EOS (1993), the results are within the permissible limit. The health risk assessment of metals was assessed on the basis of determining of EDI and THQ for inhabitants through the consumption of contaminated milk and milk products. The EDI of Cd and Pb contributed to 59.7% and 20.48% of PTDI, while Zn contributed to 0.0345 to 2.582% and 0.0475 to 3.55% of RDA for male and female, respectively, but the Cu contributed to 0.0555 to 7.466 % of RDA. The results also showed that THQ of all metals under studies are less than one via the consumption of milk and milk products which means that inhabitants in Aswan Governorate will not exposed to health risk from the consumption of raw milk and milk product.

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

This study evaluated carcinogenic and non-carcinogenic effects of metals in commonly consumed protein food samples collected from three states in Southwestern Nigeria. One hundred and fifty food samples (crayfish, fish, meat and cowskin) were collected and analyzed for Cd, Cu, Cr and Pb using the standard method. Data were evaluated for descriptive and inferential statistics using SPSS for Windows (22.0). The health risk assessments of metals (Cd, Cu, Cr, Pb) were calculated for non-cancer indices (hazard quotient, HQ and hazard index, HI) and cancer risk (CR). Results for Cd varied from 0.85 ± 0.11 mg kg−1in raw fish to 1.20 ± 0.39 mg kg−1in crayfish; Cr from 2.18 ± 0.53 mg kg−1in smoked fish to 2.71 ± 0.32 mg kg−1in crayfish, while Pb ranged from 1.40 ± 0.20 mg kg−1in smoked meat to 2.34 ± 0.62 mg kg−1in cowskin. Cu showed higher significant (p < 0.05) concentration in crayfish (19.92 ± 1.03 mg kg−1) than other protein foodstuffs. The health risk data revealed the average HI values of metals (in raw meat, smoked fish, cowskin and crayfish) greater than 1.0 indicating non-carcinogenic adverse health effects. The data on carcinogenic effects revealed CR values greater than the permissible limit of 1.0 × 10-4 for Cd and Cr indicating cancer risk on consumption of food samples.

Linking source characterisation and human health risk assessment of metals to rainfall characteristics

Metals deposited on urban road surfaces and incorporated in stormwater runoff are discharged into receiving waters, influencing their quality and can pose human health risks. Effective design of stormwater treatment measures is closely dependent on the in-depth understanding of stormwater pollutant sources and the associated health risks. The study discussed in this paper has linked the sources of metals in stormwater runoff and the accompanying human health risk to rainfall characteristics. The study outcomes confirmed that the metal contributions to stormwater runoff from the primary sources were in the order of sea salt > soil > traffic. Although traffic contributes a relatively lower percentage to wash-off, the human health risks posed by traffic sourced metals were relatively much higher. This implies that traffic sources should receive particular attention in treating stormwater. These outcomes have the potential to contribute to enhancing effective source control measures in order to safeguard natural waterways from polluted road wash-off.

Distribution Characteristics and Health Risk Assessment of Heavy Metals in a Soil-Rice System in an E-waste Dismantling Area

This study selected Guiyu Town, Guangdong Province as the research area, the content of 15 kinds of metals (As, Be, Cd, Co, Cr, Cu, Hg, Li, Mn, Ni, Sb, Sn, Pb, V, and Zn) in the soil was determined, and the content of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the rice of this research area was identified. Multivariate statistical analysis and a human health risk assessment model were used to investigate the distribution characteristics and health risk of heavy metals in a soil-rice system. The results showed that Hg, Sb, and Sn in the surface soil surrounding the electronic waste dismantling area have obvious accumulation effect. The average content of Cd and Hg exceeds the Ⅱ standard limit of the "Environmental Quality Standard for Soil" (GB 156182-1995), and that Guiyu Town is more seriously polluted than Chendian Town and Simapu Town. The multivariate statistical analysis showed that Cu, Sb, Ni, Zn, Sn, Pb, and Hg originated from the surrounding electronic waste dismantling activities, Cd and Be originated from other man-made sources of pollution, and V, Li, Cr, Co, As, and Mn originated from natural sources. Heavy metal evaluation concentration in the soil-rice system by heavy metal migration accumulated in rice are in compliance with national food hygiene standards, and the enrichment ability is Cd > Zn > Cu > Ni > As > Cr > Hg > Pb. Soil heavy metal health risk assessment results showed that children are more susceptible to heavy metal pollution, and handling-oral ingestion is the main way of soil exposure risk. The non-carcinogenic risk and carcinogenic risk of heavy metals in the soil of each town are acceptable. The health risk in Guiyu Town through ingestion of rice is mainly from the elements that include As, Cr, Cu, and Ni.

Distribution Characteristics and Health Risk Assessment of Metals in Drinking Water Sources from the Luhun Reservoir

In order to investigate the distribution characteristics and the human health risks of 12 metals in drinking water sources from the Luhun Reservoir, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, and Zn concentrations in 46 water samples collected from the reservoir in 2016 were measured and analyzed. The health risks caused by metals were assessed by using a human health risk assessment model. The results showed that the maximum concentration of Al (200.27 μg·L-1) and all concentrations of Mo (151.42-170.69 μg·L-1) in drinking water from the Luhun Reservoir exceeded the Environmental Quality Standards for Surface Water (GB 3838-2002) and Standards for Drinking Water Quality (GB 5749-2006) by 4.35% and 100%, respectively. A distinct spatial heterogeneity was found in the metal distribution, and the region with the highest metals concentrations was located southwest (upstream) and northeast (downstream) of the reservoir. The results of a health risk assessment indicated that children had greater health risks than adults. The health risks for metals through drinking were all higher than the values caused by dermal contact. Carcinogenic risks caused by Cr and As exceeded the maximum allowance levels (5×10-5 a-1) by 100% and 3.80%, respectively, and Cr accounted for 85% of the total carcinogenic risks. The non-carcinogenic risks of the metals (10-12-10-7 a-1) decreased in the order of Al > Mo > Cu > Pb > Ni > Hg > Fe > Zn > Mn, which had levels two to seven orders of magnitude lower than the maximum allowance levels.

Distribution, contents and health risk assessment of metal(loid)s in small-scale farms in the Ecuadorian Amazon: An insight into impacts of oil activities

In the last 50years, oil extraction activities in the Northeast Amazonian Region (NAR) of Ecuador impacted ecosystems and may still affect the local population health. To our knowledge, no previous studies have determined the concentrations of metal(loid)s in the oil Ecuadorian Amazon environment. A total of 15 small farms, located in the Orellana and Sucumbíos provinces, were sampled in order to determine the concentrations of As, Ba, Co, Cu, Cd, Cr, Mn, Mo, Ni, Pb, V and Zn in soils, crops, drinking water and air (PM10). Among non-essential metal(loid)s, Ba concentrations in soils exceeded the Ecuadorian limits of 200mgkg−1 in 53% of the sampling sites. In crops, Cd concentrations in cacao and Pb in manioc exceeded the FAO/WHO recommendations. In drinking water and PM10, regulated metal(loid)s did not exceed the international thresholds. Nevertheless metals such as Ba and Mo showed the highest annual mean concentrations in PM10 in both sampling sites. Natural (bedrock, volcanic ashes) and anthropogenic (oil activities, agrochemical products) sources could explain the high content of some meta(loid)s in the environment. According to the hazard quotient and cancer risk indexes, crops and water ingestion represent 71% and 88% of the exposure pathways for non-carcinogenic elements in adults and children respectively while inhalation is the main exposure pathways for carcinogenic elements for the whole population. Both indexes were 2 to 13 times higher than the US EPA recommended values. However, estimates of exposure pathways should be considered taking into account the risk perception of residents: they may be overestimated for people who are able to change their dietary and/or agricultural practices to limit their exposure, or underestimated in the case of persons who are socio-economically vulnerable and who cannot leave the impacted areas.

Effect of different cleaning processes on saponins' loss rate and total ash clearance rate of Notoginseng and heavy metal health risk assessment

Total ash clearance rates and saponins' loss rates of Panax notoginseng rhizome, root tuber, and rootlet all increased with a prolonged washing time and the rising of water temperature. Under the same conditions, the total ash clearance rates of fresh P. notoginseng were significantly higher than those dried. Meanwhile, the saponins' loss rates were opposite. The highest daily intake of bioavailability heavy metals was rootlet. However, all of that was significantly lower than the recommended daily intake, and both the target hazard quotients and hazard index values were lower than 1. Conclusion, it is effective to decrease washing time and water temperature in order to reduce the loss of saponins of P. notoginseng on the premise that ash content of Notoginseng conforms to standard of Chinese Pharmacopeias. Safety risk assessments of heavy metals based on bioavailability can further reduce the health risk of the heavy metal exposure of Notoginseng. Practical applications Notoginseng possesses the functions of hemostatic and promoting blood circulation. Clay on the surface of Notoginseng contains high content of heavy metal and induces the exceeding of standard. Washing is the most effective way to clean heavy metal attached on Notoginseng. However, research about the washing technology of Panax notoginseng is still blank. Heavy metals in Notoginseng that are taken orally are much higher than the amount actually absorbed by humans. In such a condition, the risk of heavy metals in Notoginseng will be overestimated, which may bring unnecessary loss to the development of Notoginseng industry. Therefore, this experiment researches the remaining of heavy metal under different washing water temperature and washing time. Also, we evaluate the bioavailability and risk of heavy metals in Notoginseng that are washed in an optimum condition. In this way, we provide technological parameters for the washing operation in processing P. notoginseng and referential data to set the quantity standard of heavy metal in Notoginseng.

The Distribution and Health Risk Assessment of Metals in Soils in the Vicinity of Industrial Sites in Dongguan, China.

Exponential industrialization and rapid urbanization have resulted in contamination of soil by metals from anthropogenic sources in Dongguan, China. The aims of this research were to determine the concentration and distribution of various metals (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb) and zinc (Zn)) in soils and identify their potential health risks for local residents. A total of 106 soil samples were collected from the vicinity of industrial sites in Dongguan. Two types of samples were collected from each site: topsoil (0–20 cm, TS) and shallow soil (20–50 cm, SS). Results showed that the soils were contaminated by metals and pollution was mainly focused on TS. The geoaccumulation index (Igeo) and pollution indexes (PI) implied that there was a slight increase in the concentrations of Cd, Cu, Hg, Ni, and Pb, but the metal pollution caused by industrial activities was less severe, and elements of As and Cr exhibited non-pollution level. The risk assessment results suggested that there was a potential health risk associated with As and Cr exposure for residents because the carcinogenic risks of As and Cr via corresponding exposure pathways exceeded the safety limit of 10−6 (the acceptable level of carcinogenic risk for humans). Furthermore, oral ingestion and inhalation of soil particles are the main exposure pathways for As and Cr to enter the human body. This study may provide basic information of metal pollution control and human health protection in the vicinity of industrial regions.

A quantitative risk assessment for metals in surface water following the application of biosolids to grassland

During episodic rainfall events, land application of treated municipal sludge (‘biosolids’) may give rise to surface runoff of metals, which may be potentially harmful to human health if not fully treated in a water treatment plant (WTP). This study used surface runoff water quality data generated from a field-scale study in which three types of biosolids (anaerobically digested (AD), lime stabilised (LS), and thermally dried (TD)) were spread on micro-plots of land and subjected to three rainfall events at time intervals of 24, 48 and 360h following application. Making the assumption that this water directly entered abstraction waters for a WTP without any grassed buffer zone being present, accounting for stream dilution, and modelling various performance scenarios within the WTP, the aim of this research was to conduct a human health risk assessment of metals (Cu, Ni, Pb, Zn, Cd and Cr), which may still be present in drinking water after the WTP. Different dose-response relationships were characterised for the different metals with reference to the lifetime average daily dose (LADD) and the Hazard Quotient (HQ). The results for the LADD show that child exposure concentrations were highest for Cu when the measured surface runoff concentrations from the LS biosolids treatment were used as input into the model. The results for the HQ showed that of all the scenarios considered, Cu had the highest HQ for children. However, values were below the threshold value of risk (HQ<0.01 - no existing risk). Under the conditions monitored, metal concentrations in the biosolids applied to grassland were not considered to result in a risk to human health in surface water systems.

Grain Size Distribution and Health Risk Assessment of Metals in Outdoor Dust in Chengdu, Southwestern China.

A total of 27 outdoor dust samples from roads, parks, and high spots were collected and analyzed to investigate the contamination of 11 metals (Cr, Mn, Co, Ni, Cu, Zn, As, Sr, Cd, Sb, and Pb) in Chengdu, China. The results showed that the samples from the high spots exhibited the highest heavy metal level compared with those from the roads and the parks, except for Ni, Cu, and Pb. The dust was classified into five grain size fractions. The mean loads of each grain size fraction of 11 determined metals displayed similar distribution, and the contribution of median size (63-125, 125-250, 250-500 μm) fractions accounted for more than 70% of overall heavy metal loads. The health risk posed by the determined metals to human via dust ingestion, dermal contact, and inhalation was investigated. Oral and respiratory bioaccessible parts of the metals in dust were extracted using simulated stomach solution and composite lung serum. The mean bioaccessibilities of 11 investigated metals in the gastric solution were much higher than those in the composite lung serum, especially Zn, Cd, and Pb. Ingestion was the most important exposure pathway with percentage greater than 70% for both children and adults. Risk evaluation results illustrated that children in Chengdu might suffer noncarcinogenic risk when exposed to outdoor dust. Given that the cancer risk values of Pb and Cr larger than 1 × 10(-4), potential carcinogenic risk might occur for Chengdu residents through outdoor dust intake.

Concentrations and health risk assessment of metal(loid)s in indoor dust from two typical cities of China.

Eleven trace metal(loid)s were determined in the household dust samples from Chengdu and Tianjin, China, and related human exposure and health risk to metal(loid)s via indoor dust intake were evaluated. The trace metal(loid)s were found to be highly concentrated and polluted in the indoor environment of Chengdu and Tianjin, especially for Cu, Zn, Cd, Sb, and Pb, of which the enrichment factors exceeding 5. Metal(loid) levels in the indoor dust samples exhibited no statistical differences between the two cities, with the exception of Sb, which was detected higher in the Chengdu samples. Bioaccessibilities in stomach phase of each element were estimated, Cd, Pb, and Sr exhibited higher bioaccessibility, and Sb showed the lowest bioaccessibility in both Chengdu and Tianjin. Dust ingestion was the main metal(loid) exposure pathway for Chengdu and Tianjin inhabitants, followed by dermal contact, dust inhalation accounted for less than 1% of the total daily metal(loid) intakes and thus could be negligible. Children suffered more risk when exposure to metal(loid)s via indoor dust intake due to their higher frequency of hand to mouth activities. Risk evaluation indicated that, for most Chengdu and Tianjin inhabitants, there is little non-cancer and carcinogen risk when exposure to indoor dust. However, there is a potential non-cancer and carcinogen risk for children and adults in Chengdu, in the case of highly exposed scenario based on the current study.

Arsenic and heavy metals health risk assessment through drinking water consumption in the Peshawar District, Pakistan

ABSTRACTThis study aimed to assess the drinking water quality and human potential health risk in Peshawar, which is the most populous district of Khyber Pakhtunkhwa Province, Pakistan. Water was randomly collected throughout Peshawar District (urban = 45 samples and rural = 29 samples). These samples were analyzed for heavy metal (As, Cd, Co, Cu, Cr, Hg, Ni, Pb, and Zn) concentrations using the atomic absorption spectrometer (Perkin Elmer, AAS-PEA-700). Heavy metal concentrations in drinking water revealed the highest pollution index (PI) values—17.80, 11.92, 7.50, and 5.70 for the Pb, Cr, Cd, and Ni, respectively. The contaminations of Cd and Pb were significantly higher (p < .05) than their maximum allowable limits set by the World Health Organization. Heavy metal contaminations in drinking water were evaluated for health risk assessment: the chronic risk or hazard quotient (HQ) and cancer risk. Results revealed that HQ values were >1 for the Cd and Pb, suggesting that the exposed human beings could be at chronic risk. Therefore, serious measures such as drinking water treatments and contamination controlling policies are needed to avoid the hazardous effects of toxic heavy metals.

Health risk assessment of metals in food crops and related soils amended with biogas slurry in Taihu Basin: perspective from field experiment.

A health risk assessment of food crops contaminated with heavy metals (Cu, Zn, Pb, As, Cd, and Cr) through the intake of cereals and vegetables grown from biogas slurry irrigated sites was conducted. In the vegetable soils and cereal soils, the concentrations of Zn, Pb, and Cd were far higher than Chinese agricultural standards. The pollution conditions of the aforementioned heavy metals varied with the seasons. Typically, the pollution was more serious in summer than in autumn. Furthermore, the accumulative properties of the heavy metals were different in the cereals and vegetables. In particular, Cu, Zn, and Pb tended to accumulate in rice with concentrations of 6.70, 36.58, and 4.14mgkg(-1), respectively. Pb and Cd in cereals and vegetables exceeded the maximum permissible concentrations in China. The health risk assessment revealed that the daily intake (DI) and target hazard quotients (THQs) of Pb, As, and Cd in cereals and vegetables also exceeded the FAO/WHO limit. The results indicated that heavy metal contamination posed a severe health risk to local humans.

Ecological and Health Risk Assessment of Metal in Resuspended Particles of Urban Street Dust from an Industrial City in China

Concentrations and ecological and health risks of metals in the resuspended particles of urban street dust collected from an industrial city, Baotou, China were studied. The results show that the average concentrations of Ba, Co, Cr, Cu, Mn, Ni, Pb, V and Zn in the studied samples are 990.1, 56.2, 247.8, 31.5, 566.3, 26.1, 59.9, 82.2 and 77.5 mg kg -1 respectively, which are higher than the background values of Inner Mongolia soil, especially Co, Cr and Pb. The results of potential ecological risk analysis demonstrate that Ba, Mn, V, Zn and Ni in the samples are in low ecological risk levels whereas Cr, Cu and Pb are in low to moderate ecological risk levels. Co reveals moderate to considerable ecological risk. The aggregate ecological risk of metals in the resuspended particles of street dust from Baotou is in the moderate level. Human health risk assessment shows that ingestion is the main exposure pathway of metals in dust to the local habitants. The upper limit of the 95% confidence interval of hazard indices for non-cancer risks of all analysed metals in the resuspended particles of street dust is within the safe level, while the maximum hazard index of Cr for children exceeds the safe level. Thus, the health risk of Cr for children due to dust exposure is a matter of concern. The cancer risk of Co, Cr and Ni to local habitants, considering only inhalation, is within the currently acceptable range.

Concentrations and health risk assessment of metals in chewing gums, peppermints and sweets in Nigeria

The concentrations of nine metals (Cd, Cr, Mn, Pb, Cu, Zn, Fe, Ni and Co) were measured in selected brands of chewing gums, peppermints and sweets in Nigeria with a view to providing information on the concentration profiles and dietary intakes of metals, and the life-long health hazards associated with the consumption of these food items. The metal concentrations were measured by atomic absorption spectrometry after acid digestion of the samples. The measured mean concentrations of metals in the chewing gums, peppermints and sweets were 0.16–2.21 µg/g Cd, 0.06–6.42 µg/g Cr, 0.13–13.94 µg/g Mn, <0.25–15.0 µg/g Pb, 0.08–9.81 µg/g Cu, 3.0–33.00 µg/g Zn, 10.75–140.69 µg/g Fe, <0.25–4.88 µg/g Ni and 0.08–3.44 µg/g Co. The estimated daily intake values of Cd, Pb and Co exceeded their tolerable intake limits, while the intakes of essential metals, such as Zn and Fe, from the consumption of these food items were very low and do not contribute significantly to the dietary requirements of Zn and Fe. The individual metal and combined metals target hazard quotient (\(\sum\)THQ) values were high. These indicate a serious cause of concern for both the children and adults that consume these products on a regular basis.

Source identification and health risk assessment of metals in indoor dust in the vicinity of phosphorus mining, Guizhou Province, China.

An investigation was performed to identify the sources of arsenic (As) and heavy metals in house dust and to assess the associated human health risks in the vicinity of phosphorus (P) mining in Guizhou, China. The concentrations and spatial distributions of mercury (Hg), As, cadmium (Cd), lead (Pb), iron (Fe), copper (Cu), manganese (Mn), and P in 23 house dust samples from the study area were determined. Greater concentrations of As and Pb were found compared with values in other investigations in various countries. Pollution sources were identified using multivariate statistical analysis. As, Pb, Mn, and Hg pollution was mainly attributed to mining activities, and Mn and Cd levels were largely associated with automobile emissions. The dominant wind direction and the distance of the residence from the mining region were found to play an important role in element distributions. A health risk assessment showed that As and Pb should be paid more attention, although the noncancer risks of the studied elements were within the safe range and the cancer risks of As and Cd are within the acceptable range under present conditions.