Hazard Quotient Values Research Articles

Toxic Metals Migration from Plastic Food Contact Materials in Romania: A Health Risk Assessment

Food packaging plays an essential role in preserving food quality. However, heavy metals found in packaging materials—whether intentionally incorporated or not—can migrate into food. This study aims to evaluate the migration of specific heavy metals (Ba, Co, Cu, Zn, Al, Ni, Li, Fe, Pb, Cd, Cr, Sb) from plastic food packages (films and bags) obtained from various materials (PE, PP, PVC, composite materials) into food simulant B (3% acetic acid) using inductively coupled plasma mass spectrometry (ICP-MS). Migration tests was conducted according to EU regulations, using OM2 conditions (10 days at 40 °C). The obtained results were lower than the specific migration limits set by EU Regulation no. 10/2011 (Annex II). Both carcinogenic and non-carcinogenic risk assessments were carried out based on the specific migration data, estimating the exposure, average daily dose (ADD), hazard quotient (HQ), hazard index (HI), cancer risk (CR), and total cancer risk (TCR). The exposure values were found to be below the recommended tolerable daily intake (TDI) levels for each metal tested. Both HQ and HI values were under the limit value of 1. The average total cancer risk was 1.73 × 10−4, indicating that approximately 1.73 consumers out of 10,000 may develop a type of cancer due to chronic exposure to the tested metals. These results highlight the importance of continuous monitoring of chemical migrants from food contact materials.

Exposure of school children to particulate matter and inorganic gaseous pollutants in Hawassa city, Ethiopia.

The detrimental consequences of air pollution on people, particularly vulnerable groups like children, have drawn a lot of attention globally. Studies on the levels and sources of particulate matter (PM2.5 and PM10) and inorganic gaseous pollutants (NO2, CO, and SO2) in primary schools in Africa, including Ethiopia, are scanty. Therefore, the objective of this study was to determine the levels of particulate matter and inorganic gaseous pollutants in primary schools in Hawassa, Ethiopia, and assess potential health risks. The levels of PM2.5 and PM10 were determined using a portable gas monitor device (HoldPeak Laser PM meter, HP 5800D), whereas NO2, CO, and SO2 levels were determined using the Aeroqual Series 500 Portable Air Quality Monitor (Aeroqual Ltd., New Zealand). The levels of PM2.5, PM10, and NO2 in all sampling sites ranged from 11-66.3, 30.8-399.7, and 60.5-152µg/m3, respectively. The levels of PM2.5 and PM10 were found to be above the World Health Organization recommendations in 55% and 85% of the sampling sites, respectively. The hazard quotient (HQ) values for PM10 and PM2.5 ranged from 0.3 to 3.2 and 0.2 to 1.1, respectively. The Air Quality Index (AQI) at 40% and 30% of the outdoor sampling sites was unhealthy for sensitive groups due to exposure to PM2.5 and PM10, respectively. The levels of PM2.5 and PM10, as well as the AQI and HQ values, indicate a poor condition of the air in the schools, especially in the schools near busy traffic roads.

Health risk modeling and risk factors of fluorosis in the fluoride endemic village of Maharashtra: A cross-sectional study.

Fluorosis, a debilitating disease, causes dental mottling and bone deformities among other adverse health effects. The current epidemiological study focused on the prevalence and risk factors of fluorosis in the fluoride endemic village, Dongargaon, Maharashtra, India. The clinical diagnosis of subjects showed 96.49% prevalence of dental fluorosis, and 63.16% prevalence of skeletal fluorosis. Duration of exposure, age of subjects and physiological symptoms like chronic joint pain were found to be significantly correlated with skeletal fluorosis (p < 0.05). Fluoride in drinking water showed seasonal variation with highest level in winter (6.54 mg/L) and lowest level in monsoon (0.54 mg/L). Consequently, the mean urinary fluoride concentration was also highest in winter (9.37 mg/L) and lowest in monsoon (3.88 mg/L). Multilogit regression analysis demonstrated that subjects excreting urinary fluoride above 4 mg/L had 7.25 times higher odds of developing skeletal fluorosis (p < 0.05). Health risk assessment showed a high value of hazard quotient, indicating a high probability of adverse health effects. The estimated daily ingestion of 8.80 mg F and a predicted bone uptake of 0.19 mg/kg/day raised significant health concerns for the studied population. Exposure and bone F uptake modeling suggested that the predicted mean fluoride concentrations of 4018.77 ± 1762.45 mg/kg bone ash in asymptomatic, and 5535.12 ± 1526.30 mg/kg bone ash in symptomatic subjects were significantly different (p < 0.05). The comprehensive risk evaluation in the study clearly brings out the high risk of fluoride exposure and adverse effects in Dongargaon village for the first time. Further, urinary fluoride was shown to have significant association with the risk of skeletal fluorosis. The study warrants implementation of immediate control measures at the study site.

Source appointment and health risk assessment for atmospheric carbonyls in hot tropical city, Vietnam.

The aim of this study is to assess the spatiotemporal variation, sources, and health impacts of the carbonyl compounds (carbonyls) in Ho Chi Minh City (HCMC), the third-most populous city in Southeast Asia. Sampling was conducted according to the US.EPA Method TO-11A, from 2012 to 2016 in both the dry and the rainy seasons at twelve sites. The result shows that the carbonyl mixing ratios are high when compared to typical cities. Formaldehyde, acetaldehyde, and acetone are the most abundant carbonyls together accounting for 89% of the measured carbonyls. The carbonyl mixing ratio in rainy (46.0 ± 32.2ppb) is about twofold higher than that in dry (23.7 ± 10.3ppb). An inverse distance weighting method was adopted to map the spatial distribution of carbonyls across the city. The result shows that the carbonyl levels tended to be high in the city center. Three carbonyl sources are resolved by the PCA/APCS method: industrial sources and solvent usage (54%), vehicle exhausts (24%), cooking emissions (11%). Both lifetime cancer risk (LCR) and non-cancer hazard index (HIs) were calculated to estimate the health impacts on the community due to inhalation exposure to current carbonyl levels. The LCR values vary from 5.31 × 10-6 to 5.75 × 10-5 for formaldehyde higher than those of 6.61 × 10-7 to 1.36 × 10-5 for acetaldehyde, which mostly exceeded the US.EPA recommendation for five age groups. The hazard quotient values are 12.0 to 68.4 for acrolein, 0.44 to 2.84 for acetaldehyde, 0.55 to 1.85 for formaldehyde, and 0.13 to 0.89 for propionaldehyde.

Assessing The Carcinogenic And Non-Carcinogenic Health Risk Of Heavy Metal Contamination In Soils From Ratcon Quarry Site In Ibadan, Sw Nigeria

This study estimates the health risks due to the concentration of heavy metals in the soil samples around a quarry near Ibadan, Nigeria. Soil samples were collected in triplicates (three samples collected per sampling point) from ten sampling points in the quarry site and control. The soil samples were digested for 17 heavy metals (Al, As, Co, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Pb, Sb, Se, Sn, V, and Zn) and quantified using Inductively Coupled Plasma- Optical Emission Spectrometry)- (ICP-OES). Health risk was assessed for metals including hazard quotient (HQ), hazard index (HI) and cancer risk (CR). Data obtained were subjected to descriptive (Mean ±SD) and inferential (Anova) statistics. Results showed that 16 heavy metals were detected, Fe had highest concentration (4354±17.4 mg/kg), followed by Al (1678 ±0.15 mg/kg) and Mn (192±1.29 mg/kg), Cd was not detected. The estimation of non-carcinogenic risks in this study indicated that all identified heavy metals in soils do not pose a non-carcinogenic risk to the health of children and adults. Hazard quotient (HQ) and hazard index (HI) values consistently were less than one (&lt; 1). Also, this study revealed that values of most metals assessed were below 1 × 10-6 lower limit for CR, except for chromium (1.97 X 10-1), which poses a cancer risk in adults.

Quantitative Assessment of Human Health Risks Associated with Heavy Metal and Bacterial Pollution in Groundwater from Mankweng in Limpopo Province, South Africa.

Heavy metal and microbial pollution in groundwater raises health concerns due to its adverse effects. This study aimed to assess the health risks associated with heavy metal and bacterial pollution in groundwater in Mankweng. Heavy metals and Escherichia coli were detected using inductively coupled plasma mass spectrophotometry and a Colilert system, respectively. The heavy metal pollution index (HPI) and non-carcinogenic and carcinogenic risks were computed. The β-Poisson dose-response model was employed to predict the probability of E. coli infection. The metals' concentrations were all within the permissible limits of the South African National Standard (SANS). However, Pb levels at sites E and G exceeded the World Health Organization (WHO) guideline (≤0.01 mg/L). HPI values were all less than 100, indicative of low contamination. The hazard quotient values were all less than 1, except for vanadium. The cumulative cancer risk ranged between 3.06 × 10-5 and 1.81 × 10-4 and between 3.55 × 10-5 and 2.20 × 10-4 for adults and children, respectively. E. coli was only detected at site L. The annual risk of E. coli infection exceeded the WHO risk limit of 10-4. The results underscore the need for the regular monitoring of groundwater.

Evaluating health risks of PM2.5-bound heavy elements in Faridabad, Haryana (India): an industrial perspective.

The present study isfocused on investigating the heavy/toxic metals (Al, Ni, Cr, Pb, Cu, As,Mn, and Zn) of PM2.5 and assessing their associated human health risks. During the study period (July 2022 to July 2023), the PM2.5 samples were collected from two distinct sites in Faridabad (92 samples from site 1 and 85 samples from site 2). In this study, the US EPA's Risk Assessment Guidance for Superfund (RAGS) was followed to evaluate the human health risk associated with PM2.5-bound heavy elements. The annual average of PM2.5 concentrations was 108 ± 16µgm⁻3 at site 1 and 154 ± 11µgm⁻3 at site 2, approximately three to fourtimes higher than the national ambient air quality standards (annual, 40µgm-3). The analysis of enrichment factors (EFs) for the elements Cr, As, Zn, Cu, Mn, Pb, and Ni indicates that the heavy elements associated with PM2.5 primarily originate from anthropogenic sources. The application of the conditional bivariate probability function (CBPF) model for Faridabad revealed local pollution sources contributing to elevated mass concentrations at the receptor site from the southern (S), northwestern (NW), northeastern (NE), southwestern (SW), and southeastern (SE) regions. Furthermore, positive matrix factorization (PMF) analysis identified the predominant sources of PM2.5-bound heavy elements as industrial emissions (41%), vehicular emissions (34%), and combustion processes (25%). After a thorough assessment of health hazards, Cr appeared as a significant carcinogenic risk factor. Children with elevated hazard quotient (HQ) values for Mn and Cr indicated non-carcinogenic health problems. Ultimately, this analysis reinforces the necessity for rigorous monitoring and intervention to safeguard public health from the potentially harmful effects of heavy elements.

Chemometric assessment of bioaccumulation and contamination pathways for toxic metals in diet and environment: implications for chronic kidney disease of unknown etiology (CKDu) in Sri Lankan agricultural regions.

Prolonged consumption of foods containing toxic metals can elevate the risk of noncommunicable diseases, including chronic kidney disease of uncertain etiology (CKDu). Despite the increasing number of CKDu cases in Maradankulama and Mahakanadrawa Grama Niladhari Divisions (GN) in Sri Lanka, no prior studies have examined the accumulation of heavy metal(loid)s and their potential association with CKDu prevalence. Furthermore, there is an absence of comprehensive analyses using chemometric techniques such as PCA and hierarchical studies regarding CKDu and heavy metal contamination in Sri Lanka. This study aims to provide initial insights into the accumulation and potential pathways of toxic metals in staple foods within local diets and their subsequent presence in the agricultural environment of examined GNs. Cr, Cd, As, and Ni concentrations in analyzed foods were within permissible limits (MPLs), whereas Pb levels exceeded MPLs in rice (Oryza sativa), gotukola (Centella asiatica), lime (Citrus crenatifolia), and inland fish (Etroplus suratensis). High target hazard quotient (THQt) values in polished rice suggest possible health risks with prolonged intake. Hierarchical analysis suggested a common source of Pb accumulation. PCA and hierarchical clustering revealed the intricate connection between As and Cd, with their concurrent clustering in samples suggesting a potential common origin. This indicates that while individual concentrations comply with acceptable standards, the potential synergistic effects of Cd and As accumulation might pose elevated health risks. Further, the gut tissues of inland fish exhibited pronounced metal concentrations and significant (p < 0.05) positive correlations with toxic metals in the tank sediments suggesting a diet-based bioaccumulation pathway through sediments.

Evaluation of Health Risk and Heavy Metal Pollution Caused by Dust Storms in Zabol City.

This study investigated the concentrations and compositions of specific elements in total suspended particulate (TSP) samples and the associated ecological, carcinogenic, and non-carcinogenic risks related to the inhalation, ingestion, and dermal absorption of heavy metals. The study focused on adult and pediatric populations in the highly dust-polluted city of Zabol, Iran, during 2022-2023. The samples were analyzed by using inductively coupled plasma optical emission spectrometry (ICP-OES). The concentration of metals in milligram per kilogram (mg/kg) was as follows: Al (75053) > Ca (8206) > Fe (5439) > Mg (5323) > Zn (15.27) > Pb (3.66) > Cr (3.38) > Cd (0.011); according to the results, the highest amount of metals related to aluminum and calcium in dust particles. The calculated individual indices, including the ecological risk index (ERI), pollution factor (Cfi), and geographic accumulation index (Igeo), indicated that calcium exhibited minimal pollution, while the metal samples (Al, Mg, Fe, Cd, Cr, Pb, and Zn) were categorized as uncontaminated. The results revealed that the ecological risk factor (Er) is below 40, indicating a low level of contamination. Additionally, the pollution level determined by the ecological risk potential (RI) was less than 150, suggesting a low probability of contamination. Ingestion posed the highest average hazard quotient (HQ) values for both children and adults in terms of non-carcinogenic risk assessment, while cutaneous and inhalation exposures showed lower values. Furthermore, the hazard index (HI) for heavy metals remained below the safe threshold of 1. The risk index (RI) values for lead, cadmium, and chromium were all below 1 × 10-6 in both adult and pediatric populations. The United States Environmental Protection Agency (USEPA) guidelines suggest an acceptable level of carcinogenicity for all heavy metals, indicating a potential risk of cancer associated with the presence of these metals in suspended particles in Zabol.

Human Health Risk Assessment and Water Quality Index of piped water supply system in Gulshan-e-Iqbal Town, Karachi (A Preliminary Town level study).

In the present study, piped water samples from Gulshan-e-Iqbal Town, Karachi, were evaluated for their Health Risk Assessment (HRA) and Water Quality Index (WQI). For this, different physicochemical and microbiological parameters were analyzed, and the results were evaluated according to the guidelines established by the WHO (2011) and the National Standards for Drinking Water Quality (NSDWQ) (2008). With the exception of sulphate, all physicochemical parameters were well within the guideline values. The mean concentrations of the metals in the samples were in the following order: Ca2+ > Mg2+ > Zn > Fe > Pb > Ni > Cr > As. More than 70% of the samples tested for Total Coliform Count (TCC), Total Faecal Coliform Count (TFC), Total Feacal Streptococci (TFS), and Total Aerobic Count (TAC) were feacal contaminated. E. coli was also isolated in almost 84.61% of the tested piped water samples. Results from the WQI revealed that 95.6% of samples had good physico-chemical characteristics, and 26% of the piped water samples had good microbiological quality. The WQI readings of all the samples for metals showed that they were unfit for human consumption. The mean Chronic Daily Intake (CDI) and Hazard Quotient (HQ) values, respectively, were in the following order: Zn > Fe > Pb > Ni > Cr > As, and Pb > As > Ni > Cr > Zn > Fe. All HQ values for As and Pb were greater than 1, and 50% of piped water samples had an HQ value for Ni that was greater than 1, indicating that people may suffer serious health issues as a result. All of the piped water samples except the area of block 13 D (S-5), had HQ values of less than 1 in relation to iron, but Zn HQ values of less than 1 indicated only mild health problems. Discharge of untreated sewage and cross-contamination are all potential sources of contamination that could result in diseases that are harmful to the public's health. Water monitoring and management projects should be implemented in order to improve pipeline infrastructure and reduce sewage leakages.

Pollution assessment, ecological risk and source identification of heavy metals in paddy soils and rice grains from Salem, South India

The present study investigated concentrations of metals (Cu, Zn, Fe, Mn, Ni, Pb, and Cd) in paddy soils and rice tissues of nine different widely used indica rice varieties in Salem district, India. The order of DTPA soil available metal contents (mg kg-1) were Fe (33.50) > Mn (8.86) > Cu (2.58) > Pb (1.99) > Zn (1.67) > Ni (1.48) > Cd (0.13). Pollution load index (PLI) levels for Cd (1.28) were ‘moderately polluted’, contamination factor (CF) and enrichment factor (EF) values for all metals showed ‘medium contamination’ and ‘less enrichment’ except for Cu and Pb. Ecological risk factor (ERF) and potential ecological risk index (PRI) values of Cd (31.94 and 287.50) showed ‘moderate risk’ and ‘strong ecological risk’. Bio-accumulation factor (BAF) levels of Cd (48.12) and Pb (27.89) are classified as ‘high concentrators’. Translocation factor (TF) values of Pb (2.9), Cd (2.5) and Ni (1.7) were greater than one for roots to plants. Children had higher target hazard quotient (THQ) and hazard index (HI) values for Cd, Pb and Ni than adults. Principal component analysis (PCA) revealed with all parameters that they fell within the two primary factors 1 and 2, with an eigenvalue of 4.69 (33.52% variation) and 3.73 (26.66% variation), respectively. However, cluster analysis (CA) revealed three distinct groups between the metals studied. Although the soil metal contents were within the permissible levels, the grain Cd (6.07 mg kg-1), Pb (56.20 mg kg-1), and Fe (116.11 mg kg-1) contents in all the rice varieties exceeded the prescribed limits of 0.4, 0.2, and 15 mg kg-1, respectively. Our findings will provide important data for metal enrichment in soils to implement more effective measures to reduce the contamination of metals in paddy fields.

Mineral pollutants and coliform contamination in groundwater pose health risks to consumers: a spatiotemporal study in a mining-impacted area

The presence of mineral pollutants, combined with bacterial contamination, has significantly impacted groundwater quality and led to various health-related issues in mining-impacted areas. Therefore, we measured the concentration of fluoride (F-), phosphate (PO43-), sulphate (SO42-), ammonium (NH4+), nitrate (NO3-), the total coliforms (TCs), and physiochemical characteristics in groundwater samples of South Khorasan, Eastern Iran. For this, we collected water samples from 100 wells in spring and autumn across this mining-impacted area. We then measured the concentrations of mineral pollutants and assessed their associated health risks to children and adults using the Environmental Protection Agency (EPA) models and spatiotemporal zoning maps in ArcGIS. The concentrations of PO43-, NH4+, SO42-, NO3-, and F- were 0.70 ± 0.34, 0.82 ± 0.9, 175.45 ± 123, 15.26 ± 9.41, and 0.53 ± 0.68 mg/L in spring, and 0.71 ± 3.18, 4.68 ± 31, 306.72 ± 615.80, 19.30 ± 15.61, and 0.72 ± 0.65 mg/L in autumn, respectively. PO43-, NH4+, and SO42- exceeded both the World Health Organization (WHO) and EPA, but NO3- exceeded only EPA standards. TCs in both seasons exceeded the standards set by the EPA and WHO. The hazard quotient (HQ) values indicated non-carcinogenic risks for F⁻ and NO3⁻, while posing no risks NH4⁺ and PO43⁻ in both adults and children during autumn and spring.Hazard index (HI) was greater than 1 for all minerals in both children and adults in autumn and spring. No correlation was observed between mineral compounds and TCs in the study area, yet the water samples were highly contaminated by coliform with a significant risk to adults and children. In essence, both mineral pollutants and TCs potentially pose serious risks to human, and more efforts are required to improve the quality of water in this area.

Health Risk Assessment of Ambient Air Benzene Among Primary School Children in Urban and Rural Areas in Johor, Malaysia

Introduction: It is a fact that children are vulnerable, and are at risk from benzene, a volatile, carcinogenic organic compound. The aim of our study is to determine the levels of ambient air benzene and examine the non-carcinogenic and carcinogenic risks involved Methods: A cross-sectional study was conducted in two urban and two rural primary schools in Johor, Malaysia. Benzene concentrations were measured using BUCK Libra L-4 pumps and analyzed in the gas chromatography-mass spectrometry (GC-MS). Data were collected from 334 10-12 year old children, to calculate the exposure levels based on their body weights and heights. The hazard quotient (HQ) served to evaluate the non-carcinogenic risks, whereas the lifetime cancer risk (LCR) was determined with the aid of the United States Environmental Protection Agency (USEPA). Results and Discussion: Benzene concentrations were higher in rural than urban areas, surpassing the European Union (EU) standard of 5 μg/m³. It was also established that the highest average levels recorded were 6.89 ± 6.68 μg/m³. The HQ values, nonetheless, had indicated no immediate non-carcinogenic risk, while LCR estimates were found to be within a tolerable range across all sites. Findings showed that although the immediate risk from benzene exposure is low, long-term exposure still poses a significant cancer risk to children; even low levels of chronic exposure can heighten the likelihood of children to develop cancers. Conclusion: This study has produced a revelation that there are elevated benzene levels in rural areas in Johor. Despite the low, immediate non-carcinogenic risks, further investigation on the potential for long-term cancer risks is warranted. These risks can be addressed by conducting stricter air quality monitoring, enhancing vehicle emission standards, and introducing educational programs that can raise awareness about benzene exposure.

Monitoring and Assessment of Toxicological Risks of Poultry Meat Contaminated with Heavy Metals.

This study aimed to investigate the heavy metal contamination in poultry meat of Kotli Sattian, Rawalpindi. The meat samples from ten sites were analyzed for lead, cadmium, chromium, copper, arsenic, nickel, zinc, iron, sodium, and calcium. The possible health risks of these metals were also observed. Mean lead, cadmium, chromium, arsenic, and nickel concentrations were higher than the permissible limits of the World Health Organization (WHO). Metals in meat samples showed the trend of Fe > Na > Zn > Ni > Ca > As > Cr > Pb > Cu > Cd. All the studied metals except lead were statistically significant (P ≤ 0.05). The hazard quotient (HQ) values of all the metals were below one, except iron. Iron showed chronic health risks in both adults (1.63) and children (3.64). Moreover, the cumulative hazard index (HI) of the metals indicated that meat consumption can pose a significant chronic toxic risk in both adults and children as the HI value was 2.06 for adults and 4.61 for children, which is greater than one. The carcinogenic risk (CR) of arsenic in meat for adults and children exceeded the acceptable range, making it a metal of concern. This means that the consumption of small concentrations of metal through meat may be the source of severe toxicological consequences. It can be concluded that meat is contaminated with metals; therefore, appropriate precautions should be taken to minimize this contamination.

Assessment of radioactive nuclides and heavy metals in soil and drink water in Lahij city, Yemen

This study was conducted in Lahij city, Yemen, to evaluate the concentrations and potential health risks of natural radioactive nuclides and heavy metals in soil and drinking water. A total of 21 soil samples and 17 water samples were collected from various locations. A high-purity germanium gamma detector HPGe was used to measure the concentrations of 40K, 232Th, and 226Ra in all samples, along with the concentrations of heavy metals. In soil samples, the average concentrations of 40K, 232Th, and 226Ra were 731.5, 30.7, and 28.16 Bq kg−1, respectively. While some samples showed higher than permissible levels for 226Ra and 232Th, the overall average remained within acceptable limits. However, 40K levels were almost twice the recommended global limits. In water samples, the average concentrations of these nuclides were 5.38, 0.73, and 0.66 Bq L−1, all within the global safety limits. Radiological risk assessments for soil indicated an average radium equivalent activity (Raeq) of 124.4 Bq kg−1, absorbed dose rate in air of 59.9 nGy h−1, annual effective dose rate of 0.07 mSv y−1, outdoor excess lifetime cancer risk (ELCR) of 0.26 × 10−3, and annual gonad equivalent dose (AGED) of 336.6 mSv y−1. Risk indices, including the activity concentration index (Iγ), external hazard index (Hex), and internal hazard index (Hin), averaged 0.48, 0.34, and 0.41, respectively, all below global limits except for AGED, which slightly exceeded the recommended level. For drinking water, the total ingestion dose was calculated for different age groups. The average doses for infants, children, and adults were 0.15, 0.27, and 0.19 mSv y−1, respectively. The doses for children and adults exceeded the permissible limits, while those for infants were within safe levels. Heavy metal concentrations were measured in all samples, and the Hazard Quotient (HQ) was calculated. In soil samples, HQ values for all metals >1, indicating potential health risks. In water samples, HQ values were also >1 for all metals except vanadium (V) and iron (Fe). To reduce the dangers associated with radioactive nuclides and heavy metals, regular monitoring and cleanup are crucial, and further research is needed to understand contamination sources and long-term health impacts.

Determination of heavy metals and health risk assessment in drinking water in Bukayriyah City, Saudi Arabia

Abstract Heavy metal levels, including arsenic, lead, cadmium, mercury, chromium, and nickel, were analyzed in 124 samples of tap and filtered water obtained from Bukayriyah city, Saudi Arabia, using inductively coupled plasma mass spectrometry. Additionally, measurements of total dissolved solids, conductivity, and pH were also performed. The study also evaluated the potential non-cancer and cancer risks (CRs) associated with the ingestion of these heavy metals for both children and adults. The results indicated that the average concentrations of heavy metals in both tap and filtered water were found to be below the recommended limits set by the World Health Organization and the Gulf Standard Organization. To assess the non-carcinogenic risks, the chronic daily intake (CDI), hazard quotient (HQ), and hazard index were calculated for analyzed metals present in both tap and filtered water. In both the children and adult populations, the CDI indices for heavy metals in tap and filtered water followed the order of Cr &gt; Hg &gt; Ni &gt; Pb &gt; As &gt; Cd. However, it is worth noting that the CDI values for tap water were higher than those for filtered water for both children and adults. The descending order of HQ values is as follows: Hg &gt; Cr &gt; As &gt; Cd &gt; Pb &gt; Ni. This indicates that the HQ values for all metals are below the acceptable limit of 1. These findings confirm that the exposure to the examined metals from both tap and filtered water in Bukayriyah City is within safe limits and poses no non-carcinogenic risks. To assess the carcinogenic risks, the incremental lifetime cancer risk (ILCR) and total carcinogenic risk (TCR) were calculated. The order of ILCR values for both children and adults in tap and filtered water is as follows: Ni &gt; Cr &gt; Cd &gt; As &gt; Pb. All ILCR values were below the acceptable limit of 10−6 to 10−4. However, TCR values exceeded this threshold range only for children exposed to tap water, with a value of 1.43 × 10−4. Thus, children exposed to tap water have a potential risk of developing carcinogenic diseases.

Long-term analysis of BTEX concentrations and health risks in semi-arid urban regions

Rajasthan, experiencing rapid industrialization and urbanization, faces critical air quality challenges, particularly concerning toxic volatile organic compounds (VOCs) such as BTEX (Benzene, Toluene, Ethylbenzene, Xylene). This study presents a long-term analysis of BTEX concentrations across various cities in Rajasthan, India, using data from the Central Pollution Control Board (CPCB) from 2017 to 2022. The findings revealed that the average ∑BTEX concentrations increased from 4.15 µg/m3 in 2017 to 12.29 µg/m3 in 2022, with a temporary decline in 2020. The Hazard Quotient (HQ) values for BTEX exposure ranged from 0.052 to 0.15 for males, 0.056 to 0.17 for females, and 0.09 to 0.29 for children over the study period, indicating higher health risks for children. Similarly, the Lifetime Cancer Risk (LCR) values varied from 6.04 × 10⁻⁶ to 1.92 × 10⁻5 for males, 1.09 × 10⁻⁶ to 2.24 × 10⁻5 for females, and 1.17 × 10⁻5 to 3.73 × 10⁻5 for children. The results demonstrate that children are at a greater cancer risk from BTEX exposure compared to adults. This study emphasizes the urgent need for effective air pollution control measures and continuous monitoring to protect public health, particularly vulnerable populations like children.

Heavy metal contamination in Lebanese lettuce: Quantification and health risk assessment

Heavy metals (HM) contamination in food products is a major risk to public health. Lebanon is constantly suffering from unresolved environmental pollution issues, which have led to an increase in atmospheric deposition of contaminants in water and soil. This study aims to investigates the levels of HM in Lettuce products collected from different market regions in Lebanon. We also estimated the potential human exposure to HM through ingestion of lettuce. We used the Atomic Absorption Spectrophotometry to determine HM levels in the collected samples. Furthermore, we calculated the Metal Pollution Index (MPI) and the Hazard Quotient (HQ) to determine the expectance of adverse health effects in comparison to other countries. The results showed that Lead (Pb), Arsenic (As) and Chromium [Cr (III)] levels in the capital city exceeded the maximum allowable values set by FAO/WHO, whereas Palladium (Pd) was above the safety limit in all collected samples. The MPIs fluctuated over all investigated regions but remained below the critical value (of 1). However, the maximum As HQ exceeded the permissible limit by 186 % and the maximum Pb HQ value was higher than that of industrialized countries including China, Brazil, and Egypt. These findings prove that regular testing and monitoring are highly required to investigate the importance of human exposure to HM in Lebanon and any associated health impacts.

Spatial distribution, ecological and human health risks of potentially toxic elements (PTEs) in river Ravi, Pakistan: A comprehensive study

Significant quantities of potentially toxic elements have been and are still being discharged into Pakistan's rivers through natural sources and anthropogenic activities. The present study provides a comprehensive study of potentially toxic element contamination in the water and sediment of the Ravi River, Pakistan. The research aims to examine the extent of pollution, its ecological risks, and the potential human health impacts through detailed geospatial analysis and statistical correlation. Water and sediment representative samples were taken and analyzed for potentially toxic elements, including Cobalt (Co), Cadmium (Cd), Zinc (Zn), Nickel (Ni), Arsenic (As), Chromium (Cr), Lead (Pb), Copper (Cu), and Manganese (Mn). Various pollution indices, such as the “Geo-accumulation Index (Igeo), Modified degree of Contamination (mCd), Nemerow comprehensive pollution index (Pt), Contamination factor (CF), Enrichment factor (EF), Pollution Load Index (PLI), and Potential Ecological Risk Index (PERI),” were calculated to determine the contamination levels and ecological risks. The results indicated significant spatial variability in metal concentrations, with higher levels observed in industrial and urban areas (near Lahore). Cd and As were identified as the most critical pollutants, exhibiting high Igeo, CF, EF, and PERI values. The PLI revealed that several regions along the river are heavily polluted. Pt shows high comprehensive pollution near Lahore and moderate to high pollution in surrounding areas. According to mCd, most of the study area, especially sampling points near Lahore, ranges between 8 and 16, indicating a high degree of pollution. The Human Health Risk (HHR) assessment, considering ingestion, inhalation, and dermal contact pathways, highlighted that children are particularly vulnerable, showing higher Hazard Quotient (HQ) and Hazard Index (HI) values for several metals. Correlation analysis revealed significant relationships between certain metals, suggesting common sources of contamination, likely from industrial discharges and urban runoff. The comprehensive mapping and statistical analysis underscore the urgent need for implementing effective pollution control measures to mitigate the risks posed by potentially toxic element contamination in the Ravi River. This study provides critical insights for policymakers and environmental managers to prioritize areas for remediation and to develop strategies to protect both ecological and human health in the region.

Spatial distribution and risk assessment of perchlorate in raw cow milk from China

Perchlorate is a ubiquitous environmental contaminant worldwide, recognized as an emerging thyroid toxicant. This study focused on the pollution status, spatial distribution, possible sources of perchlorate in raw cow milk collected from 155 dairy farms in China, as well as the health risk of exposure to perchlorate through dairy products. The results showed that the detection rate of perchlorate in raw milk was 100% with the mean of 15.9 μg/kg, indicating the ubiquitous contamination of perchlorate in raw milk from China. The simulation of spatial distributions indicated that the levels of perchlorate in raw milk were spatially correlated, and relatively high levels of perchlorate exist in certain parts of Beijing-Tianjin-Hebei, Shanxi, Henan, and Zhejiang, suggesting potential environmental perchlorate contamination in these regions. A positive correlation was found between the perchlorate level in milk and the perchlorate level in feed, indicating the transfer process of perchlorate from feed to milk. The hazard quotient (HQ) values of exposure to perchlorate by dairy products ranged between 0 and 2.14, with the mean of 0.0188 and P95 of 0.101, indicating relatively low health risk to perchlorate through dairy products. To our knowledge, this is the first nationwide study on the spatial distribution and risk assessment of perchlorate in raw cow milk from China.