Lifetime Cancer Risk Values Research Articles

Nutrient Interaction and Health Risk Assessment of Cereal Grains on Nigerian’s Markets

Background: Cereals are the most staple foods in human diet and the main components of the daily diet. This work was designed to determine the level of essential and non-essential elements, the in vitro bioavailability, interrelationship, and associated health risk in consumed cereal grains in Nigeria to assess their safety and wholesomeness.
 Methods: The contents of phytate, oxalate, and some major-, trace- and potentially toxic elements were determined in 36 samples of barley, maize, millet, rice, sorghum, and wheat marketed in Nigeria.
 Results: The data showed variable significant (p<0.05) levels of elements, phytate, and oxalate in the cereals but they were below European commission maximum permissible limits. Estimated daily intakes (EDIs) of elements in the cereals were all below maximum permissible limits set by European Food Safety Authority (EFSA). Hazard Quotient (HQ) and Hazard Index (HI) values, though higher in children than adults, were less than one except in wheat and sorghum. The incremental lifetime Cancer Risk (CR) and Total Cancer Risk (TCR) values were below the threshold limit.
 Conclusion: This study revealed that barley, maize, millet, rice, sorghum, and wheat available in Nigeria markets contain varying quantities of essential elements, potentially toxic elements, and antinutrients.

Pollution Characteristics and Carcinogenic Risk Assessment of PAHs in Car Dust Collected from Commercial Car Wash in Changchun, Northeast China

In the collection of dust, vacuum cleaners are used to clean everything inside the car, including floor/carpet, seat, console, etc. To investigate the characteristics, possible sources and carcinogenic risks of polycyclic aromatic hydrocarbons (PAHs) contamination in car dust, fourteen car dust samples were collected from commercial car washes in Changchun, Northeast China. The 16 priority PAHs were all detected in 100%, and PAHs were predominantly tetracyclic. The mean ∑16PAHs content was 9297.79 ± 5855.89 ng g−1, ranging from 2940.03 to 23,174.51 ng g−1. Black carbon, total carbon and PAHs were weakly correlated. The results of positive matrix factorization indicated that coal combustion contributed 30.03% of PAHs and biomass combustion contributed 24.70%. Vehicle exhaust from traffic emissions, mainly incomplete combustion of gasoline and diesel, contributed 45.27% of PAHs. The mean incremental lifetime cancer risk (ILCR) values for children and adults were 4.94 × 10−3 and 4.37 × 10−3, respectively, both above the threshold value of 10−4. This indicates that PAHs from car dust put both adults and children at high carcinogenic risk, and that children are exposed to a higher carcinogenic risk than adults. This study provides a basis for proposing targeted measures to control PAHs’ contamination from car dust.

Elemental Profiling of North-East Indian Tea (Camellia sinensis) by ICP-MS and Assessment of Associated Health Risk.

Tea is a perennial crop that requires acidic soil for better plant growth. Due to the acidic nature of tea-growing soil, metals can be easily absorbed by tea plants from growing medium. Other anthropogenic activities are also the major contributor of element in the tea. This study provided a comprehensive database of 24 elements which were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Selected 24 elements belong to alkali metal (Li, Rb, Cs), alkaline earth metal (Be, Sr, Ba), transition metal (V, Cr, Mn, Co, Ni, Cu, Zn, Ag, Cd, Hg), basic metal (Al, Ga, Sn, Tl, Pb), metalloid (As), non-metal (Se), and actinide (U). Total 321 drier mouth samples were collected during 2020-2021 from eight different regions (Darjeeling, Terai, Dooars, North Bank, Upper Assam, South Bank, Cachar, and Tripura) of north-east India. No inorganic mercury as well as uranium was detected in any tested tea samples. Mean concentrations of Be, As, Ga, Tl, Li, Se, Cd, Ag, Cs, V, Co, and Pb were at trace level, whereas macro-element mean concentrations were distributed in the manner of Al > Mn > Rb > Ba > Zn > Cu > Sr > Cr > Ni > Sn. Human health risk for non-carcinogenic and carcinogenic metals was also assessed for the studied elements. Hazard quotients (HQs) and hazard index (HI) values (< 1) for non-carcinogenic elements indicated no risk. The incremental lifetime cancer risk (ILCR) values for carcinogenic elements indicated no risk for As, Cd, and Pb and medium level risk for Ni. Study concluded that north-east Indian tea would not pose any health hazard.

Polybrominated diphenyl ethers and polycyclic aromatic hydrocarbons in dust from different indoor environments in Zagreb, Croatia: Levels and human exposure assessment.

The present study reports for the first time the levels of 7 polybrominated diphenyl ether (PBDE) congeners and 11 polycyclic aromatic hydrocarbons (PAH) measured in dust samples collected in 10 kindergartens, 11 workplaces, and 25 cars from Zagreb, Croatia. ΣPBDEs mass fractions were 3.11-14.42, <LOD-313.75, and 0.6-5666.98 ng g-1 dust, while ΣPAHs were 244.9-833.0, 230.5-5632.7, and 395.6-12114.8ng g-1 dust in kindergartens, workplaces, and cars, respectively. In the central case scenario, dust from homes contributed to the intake of PBDEs and PAHs the most, while for PBDEs in the worst-case scenario, the intake through car dust prevailed. Carcinogenic and non-carcinogenic risks were assessed for PAHs and PBDEs, respectively, for two age groups (adults and toddlers) and for professional drivers as a specific group. The hazard index for adults, toddlers, and professional drivers for PBDEs was less than 1 indicating that there is no significant risk of non-carcinogenic effects due to exposure to these chemicals. Total carcinogenic risk for PAHs was negligible for all groups in the central case scenario, but the Incremental Lifetime Cancer Risk values >10-6 in the worst-case scenario indicated a potential risk, especially for professional drivers. Also, in the cases of elevated contaminant levels, toddlers are susceptible to a higher risk, despite the short time they spend in cars.

Health risk assessment of hazardous VOCs and its associations with exposure duration and protection measures for coking industry workers

Coke making is extremely problematic from the environment and health perspectives, as the massive hazardous volatile organic compounds (HVOCs) being driven off during the coking process. Here, we conducted a health risk assessment study on coking workers, through on-situ HVOCs measurements and questionnaire investigation on activity time parameters and protection measures. The ambient HVOCs at major working stations were 58.4–376.5 μg/m3 with relative deviation of 59.4% for the certain station. The total working hours during career would reach 43283–51695 h, and protection efficiency (PE) to resist HVOCs inhalation ranged from 16% to 87%. According to the exposure evaluation model recommended by the U.S. EPA, there was little non-cancer risk for the workers at most positions with hazard quotient (HQ) value of less than 1; however, the cancer risk widely existed with lifetime cancer risk (LCR) value of 3.6–15.0 × 10−6, in which benzene, 1,2-dichloropropane, 1,2-dichloroethane, and 1,3-butadiene were dominant inducers. The cancer risk regarding the large plants was about 28.6% lower compared to the small and medium plants, due to the greater PE. In terms of the response of the health risk to exposure duration (ED, working years) and PE, non-cancer risk effectively responded only for the byproduct recovery stations, while cancer risk more sensitively responded for all stations. Health risk management therefore is essential, and the potential health hazards can be avoided by limiting ED and strengthening PE. For workers in coking, byproduct recovery and office areas, the PE should be higher than 93.8%, 97.7% and 77.3% under the ED of 20 years, the ED in three areas should be lower than 12.5 years, 4.5 years and 30 years under PE of 90%, respectively.

Seasonal variability, predictive modeling and health risks of N-nitrosamines in drinking water of Shanghai

The prevalence of carcinogenic N-nitrosamines in drinking water is of significant concern. In the present study, eight N-nitrosamines from three representative drinking water treatment plants (DWTPs) in Shanghai, China were monitored for an entire year to evaluate their seasonal variability, probabilistic cancer risk and the resulting disease burden. The possibility of employing routinely monitored water quality parameters as predictors of N-nitrosamines was also examined. The results showed that the Taipu River-fed reservoir suffered more serious N-nitrosamine contamination than the Yangtze River-fed reservoirs. Winter witnessed higher levels of N-nitrosamines in both source and finished water. N-nitrosamine concentrations increased from source water to finished water in autumn or winter, but no spatial variations were observed in summer. The total lifetime cancer risk (LCR) posed by N-nitrosamines in finished water was within the acceptable range (1.00 × 10−6 to 1.00 × 10−4), with N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) being the main contributors. Winter and autumn were found to have higher total LCR values. The average individual disability-adjusted life years (DALYs) lost was 4.43 × 10−6 per person-year (ppy), exceeding the reference risk level (1.00 × 10−6 ppy). Liver cancer accounted for 97.1 % of the total disease burden, while bladder and esophagus cancers made a little contribution (2.9 %). A multiple regression model was developed to estimate the total N-nitrosamines in finished water as a function of water quality parameters, and the R2 value was 0.735. This study not only provides fundamental data for public health policy development, but also reveals the necessity to incorporate a seasonal control strategy in DWTPs to minimize the associated health risks induced by N-nitrosamines.

Prevalence of arsenic contamination in rice and the potential health risks to the Bahamian population—A preliminary study

Rice is among the most important staple foods worldwide. However, the consumption of rice and rice-based food products poses a potential health risk since rice is a paddy crop that is well known to accumulate high concentrations of arsenic (As) in its grain. In The Bahamas, although rice is heavily consumed, it is not grown locally. Instead, all the consumed rice and its derived products are imported. Recent food surveys in the major rice exporting countries have shown that a significant portion of their market rice products is contaminated with As. However, to date, the prevalence of As in the rice foods available in The Bahamas remains unknown. Therefore, in this study, we surveyed the occurrence of As in a selection of rice and rice products that were on sale in the Bahamian market. A total of 21 different rice brands were collected. The concentration of As and the potential health risk were estimated by target hazard quotient (THQ), hazard index (HI), and lifetime cancer risk (LCR). Our results showed that only the blue ribbon samples had an estimated inorganic arsenic (iAs) concentration above the World Health Organization (WHO) safety limits (200 μg/kg), which is based on global average consumption. However, when we factor for average rice consumption in The Bahamas, 79% of the rice samples had iAs concentration values indicative of carcinogenic risks and 57% had iAs concentration values that suggested non-carcinogenic health risks. Based on our results, we recommend urgent follow-up studies to further test rice varieties that show the greatest LCR and HI values and to also broaden the study to include more off-brand/generic varieties, cooked rice, and drinking water.

Is Poland at risk of urban road dust? Comparison studies on mutagenicity of dust

Depopulation concerns many polish cities, with the exception of a few metropolises such as Wrocław (Lower Silesia) and Katowice (Upper Silesia) where investments are growing and therefore more humans are exposed to urban environmental pollution. Accumulation of toxic substances on road surfaces is a major global challenge requiring methods of assessing risk that initiate the proper management strategies. In this study urban road dust (URD) has been collected at seventeen sites in Lower and Upper Silesia regions in Poland renowned for their elevated level of pollution. The aim of the study was: (i) to determine PAH concentration in URD in both regions with the identification of their possible sources based on diagnostic ratio; (ii) to assess possible mutagenic effects of URD with the application of Ames test (Salmonella assay); (iii) to define a possible carcinogenic risk related to URD in both studied regions. We found that the total PAH content of collected URD samples ranged from 142.4 to 1349.4 ng g−1. The diagnostic ratio of PAHs in URD for all studied sites showed that pyrogenic combustion predominated indicating traffic-related and biomass sources of pollution. The Ames assay, which has never been used in studies of URD in Poland, demonstrated that in both regions, URD samples (from eight sites), were characterised by the highest mutagenicity values. Additionally, Incremental Lifetime Cancer Risk (ILCR) values, based on PAH content only, were between 10 and 6 to 10−4 indicating potential risk of cancer. Reassuming, humans in both agglomerations are exposed to factors or compounds with carcinogenic properties which may have an adverse health effect through the urban road dust mainly due to vehicular traffic, heating systems and industrial activities.

Microplastics-sorbed phenanthrene and its derivatives are highly bioaccessible and may induce human cancer risks.

Microplastics (MPs) are ubiquitous in environmental media and human diets and can enrich organic contaminants, including polycyclic aromatic hydrocarbons (PAHs) and their derivatives. The bioaccessibilities and triggering cancer risks of MP-sorbed PAHs and PAH derivatives are closely linked with human health, which, however, were rarely focused on. This study explored the sorption behaviors of phenanthrene (PHE) and PHE derivatives on polyethylene (PE), polypropylene (PP), and polystyrene (PS) MPs, and assessed their bioaccessibilities in gastrointestinal fluids as well as their inducing human cancer risks. PE MPs harbored the highest sorption capacity, secondly the PP MPs, then the PS ones. Sorption of PHE and PHE derivatives on MPs was positively correlated with their hydrophobicities. The bioaccessibilities of sorbed PHE and PHE derivatives could reach 53.59%±0.46%-90.28%±0.92% in gastrointestinal fluids and 81.34%±0.77%-98.72%±1.44% in gastrointestinal fluids with the addition of Tenax (more close to the bioavailability). The hydrophobicities also controlled the bioaccessibilities of PHE and PHE derivatives in gastric fluids, and those in intestinal fluids with Tenax for PS MPs. The incremental lifetime cancer risk (ILCR) values for PHE, PHE-Cl, and PHE-NO2 on MPs at tested concentrations were all higher than the USEPA-suggested safety limit (10-6), and most of them were even higher than 10-4, which thus indicates serious cancer risks. This study promoted our understanding of the potential health threats posed by organic pollutant-bearing MPs in the environment.

Assessment of cause-specific mortality and disability-adjusted life years (DALYs) induced by exposure to inorganic arsenic through drinking water and foodstuffs in Iran

The health risk and burden of disease induced by exposure to inorganic arsenic (iAs) through drinking water and foodstuffs in Iran were assessed. The iAs levels in drinking water and foodstuffs (15 food groups) in the country were determined through systematic review of three international databases (PubMed, Scopus, and Web of Science) and meta-analysis. Based on the results of the systematic review and meta-analysis, the average iAs levels in drinking water and all the food groups at the national level were lower than the maximum permissible levels. The total average non-carcinogenic risk of dietary exposure to iAs in terms of hazard index (HI) was 3.4. The average incremental lifetime cancer risk (ILCR) values of dietary exposure to iAs were determined to be 1.5 × 10−3 for skin cancer, 1.0 × 10−3 for lung cancer, and 4.0 × 10−4 for bladder cancer. Over two-thirds of the non-carcinogenic and carcinogenic risk of dietary exposure to iAs was attributed to bread and cereals, drinking water, and rice. The total annual cancer incidence, deaths, disability-adjusted life years (DALYs), death rate, and DALY rate (per 100,000 people) were assessed to be 3347 (95 % uncertainty interval: 1791 to 5999), 1302 (697 to 2336), 72,606 (38,833 to 130,228), 1.6 (0.87 to 2.9), and 91 (49 to 160). The contribution of mortality in the attributable burden of disease was 95.1 %. The contributions of the causes in the attributable burden of disease were 72 % for lung cancer, 16 % for bladder cancer, and 12 % for skin cancer. Due to the significant attributable burden of disease, national and subnational action plans consisting of multi-disciplinary approaches for risk management of dietary exposure to iAs, especially for the higher arsenic-affected areas and high-risk population groups in the country are recommended.

Spatial-temporal distribution and pollution indices of heavy metals in the Turnasuyu Stream sediment, Turkey.

The potential contamination levels and human health risk of heavy metals in sediment of the Turnasuyu Stream in Ordu, Turkey, were evaluated comprehensively by taking seasonal samples from three different locations. The order of the mean heavy metals (HMs) concentrations (mg/kg) were as follows: Fe > Al > Mn > Pb > Zn > Cu > Co > Cr > Ni > Cd > As. All HM levels, except Cd and Pb, were in the minimum enrichment range as assessed by the sediment enrichment factor (EF). Similar low contamination levels for all HM, except Pb and Cd, were also observed when the contamination factor (CF) and geo-accumulation index (Igeo) were taken into account. The low risk of the study area has also been confirmed by the ecological risk index (Eri) values. The probable human health risk assessment has been performed, and the lifetime cancer risk (LCR) values for adults were found as negligible with values below 10-6. In addition, the hazard index (HI) and total hazard index (THI) results were both higher in children than in adults. The Pearson correlation coefficient (PCC) revealed the highest correlation between Cd and Pb (0.85). When the ecological indexes and statistical results are evaluated together, it is thought that the presence of HMs in the sediment may be due to lithological reasons as well as anthropogenic activities such as quarrying, municipal, agricultural, and domestic discharges in the region. Mitigation measures should be taken in accordance with the standards within the river basin to prevent the potential risks of pollution.

Chemical characterization and health risk assessment of VOCs and PM2.5-bound PAHs emitted from typical Chinese residential cooking

Cooking is a major source of indoor air pollution. Existing studies suggest that organic material is the most abundant component by mass in cooking emissions, while the detailed organic species that result from cooking remains poorly understood. This work provides a comprehensive foundational knowledge of emission arising from typical Chinese residential cooking based on a field-work measurement of polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), and the routinely measured fine particulate matter (PM2.5) composition. Exposure to the Chinese cooking procedures will likely pose a significant health risk, with grilling producing the highest PM2.5 concentration (28.79 ± 9.36 mg m−3) and the most distinctive composition among the cooking patterns. The PAHs with 3 rings dominated the total PAHs by mass (48.08%), with the major organic species Phenanthrene (Phe), Anthracene (Ant), Benzo [a] pyrene (BaP), and Fluorene (Flu), accounting for 0.0399–0.5966, 0.0091–0.6710, 0.0046–0.4531, and 0.0086–0.3102 ng per μg of PM2.5, respectively. Oxygenated VOCs (OVOCs) accounted for 37.98% of the total VOCs. The ratios of Fla/(Fla + Pyr) and IcdP/(IcdP + BghiP) helped in distinguishing residential cooking emissions from other sources. The incremental lifetime cancer risk (ILCR) values of PAHs and VOCs were 6.9 × 10−6–1.8 × 10−5 and 2.7 × 10−6–1.8 × 10−3, respectively, which were substantially higher than the acceptable levels (1.0 × 10−6) established by the U.S. EPA. The considerable health risks posed by Chinese cooking emissions necessitate additional study and control measures to lessen indoor air pollution and protect human health.

Health ecological risk assessment of natural radionuclides and heavy metals in some sediment at Red Sea coast, Egypt

ABSTRACT The main objective of this study was to evaluate the health and ecological risks of natural radionuclides and heavy metals based on 23 sediment and water samples collected from some sediment at the Red Sea Coast in Egypt. The studied area is characterised old harbour used for shipping and processing phosphate ore. The results revealed that Cd and Zn contents in some water and sediment samples exceeded the standard limit, their concentrations reached (0.027–0.09) mg/L in water and (4.5–236) mg/Kg in sediment samples respectively. While the other analysed trace elements Fe, Mn, Ni, pb and Cu remain below permissible limits. The estimated contamination degree varied from low to considerable while the ecologic risk indices revealed that sediment ranged 10.8 to 466.6 as from low to moderately contaminate with trace elements. The average activity concentrations of 238U, 232Th, and 40K were 3.4, 0.83 and 5.5 Bq/L in water and 63.5, 16.5 and 556 Bq/Kg in sediment samples which were below the recommended limits except for the activity concentrations of 238U and 40K in some water and sediment samples above the permissible limits. The total annual effective dose rates from the exposure pathway were 0.09 to 0.26 mSv y−1. The estimated excess lifetime cancer risk values for workers were slightly higher than that of the sediment world average.

Natural Radionuclides in Bottled Mineral Waters Consumed in Turkey and Their Contribution to Radiation Dose.

Bottled natural mineral water (BMW) consumption in Turkey is increasing every year. Depending on the local geology from which the water is extracted, BMW could be enhanced with natural radionuclides. In this study, the activity concentrations of natural radionuclides in 58 BMW samples of 25 different brands marketed in Turkey were measured using a γ-ray spectrometer with high-purity germanium (HPGe) detector. The average activity concentrations of 226Ra, 228Ra, and 40K in BMW samples were found as 0.4, 0.5, and 4.3 Bq/L, respectively. The activity concentrations of 228Ra exceeded the WHO-recommended maximum permissible limit of 0.1 Bq/L for drinking water. The annual effective dose (AED) and excess lifetime cancer risk (LCR) caused by the ingestion of each BMW sample were estimated for adults to assess radiological risks using two different scenarios based on BMW consumption rates (150 and 13 L/y). All estimated total AEDs, except for two samples, were below the guidance dose level of 100 μSv/y recommended by the World Health Organization (WHO) and Turkish regulations for drinking water. For all BMW brands, 228Ra was found as the main contributor to the AEDs. The LCR values were lower than the acceptable value of 10–3 for radiological risks.

Pollution levels, sources and risk assessment of polycyclic aromatic hydrocarbons in farmland soil and crops near Urumqi Industrial Park, Xinjiang, China

This study investigated the concentration, source, and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in farmland soil and crops around the Urumqi Industrial Park in Xinjiang, China. The total concentration of 16 different PAHs in the soil (Quantity: 51) and crop (Species: onion, cabbage, coriander, beans, spinach, celery, lettuce, and sunflower) samples ranged between 2.32 and 225.11 ng/g and between 132.44 and 504.03 ng/g respectively, with average values of 39.29 ± 2.39 ng/g for the soil samples and 295.81 ± 105.00 ng/g for the crop samples. The source analysis of PAHs was performed using the positive matrix factorization and ratio method and identified the high-temperature combustion of fossil fuels, the volatilization of petroleum, coke oven emissions, and traffic emissions as main sources of PAHs in soil. The ecological risk posed by the PAHs detected in the soil samples was within a safe range. The incremental lifetime cancer risk (ILCR) value quantifies resulting from human exposure to soil containing PAH is at a safe level except for the potential carcinogenic risk to children due to ingestion exposure (ILCRs > 1.0 × 10–6). The ILCR posed by crops exceed 1.0 × 10–6 and the risk from sunflower crop was the highest. The highest ILCR values for each crop high exposed for the adult female population. These results indicate that the farmland soil and crops near the Urumqi Industrial Park have been contaminated by PAHs and require urgent remediation to minimize adverse effects of exposure to carcinogens.

Cosmetics Trace Elemental Content: Analytical Methodology and Toxicity Evaluation of Products in the Italian Market

A new method for the determination of five trace metals (Pb, Co, Cd, Cr, and Ni) in make-up products was developed. Quantification of the metals was performed by inductively coupled plasma – mass spectrometry (ICP-MS). The specificity, precision, applicability range and linearity, the minimum detection limit, repeatability, trueness, and uncertainty of the method were assessed by a top-down approach. The method was applied to 90 cosmetic products in the Italian market and only Pb and Cd were always lower than limits for cosmetic products proposed by the Istituto Superiore Sanità (Italian National Institute for Health, ISS). The metal concentrations allowed the evaluation of the risk levels of exposure to these elements. Except for a few cases, the calculated margin of safety (MOS), margin of exposure (MOE), and lifetime cancer risk (LCR) values were all below the risk threshold levels. Based on the maximum concentrations of metals determined in the cosmetics, the dose of systemic exposure (SED) ranged from 8.00 x 10−12 to 3.39 x 10−7 mg/kg/d. The risk was also described from the hazard index (HI). The metals in each cosmetic product show an MOE higher than the threshold limit except for Cr in eyeshadow.

Temporary reduction in VOCs associated with health risk during and after COVID-19 in Maharashtra, India.

A novel coronavirus has affected almost all countries and impacted the economy, environment, and social life. The short-term impact on the environment and human health needs attention to correlate the Volatile organic compounds (VOCs) and health assessment for pre-, during, and post lockdowns. Therefore, the current study demonstrates VOC changes and their effect on air quality during the lockdown. The findings of result, the levels of the mean for total VOC concentrations were found to be 15.45 ± 21.07, 2.48 ± 1.61, 19.25 ± 28.91 µg/m3 for all monitoring stations for pre-, during, and post lockdown periods. The highest value of TVOCs was observed at Thane, considered an industrial region (petroleum refinery), and the lowest at Bandra, which was considered a residential region, respectively. The VOC levels drastically decreased by 52%, 89%, 80%, and 97% for benzene, toluene, ethylbenzene, and m-xylene, respectively, during the lockdown period compared to the previous year. In the present study, the T/B ratio was found lower in the lockdown period as compared to the pre-lockdown period. This can be attributed to the complete closure of non-traffic sources such as industries and factories during the lockdown. The Lifetime Cancer Risk values for all monitoring stations for benzene for pre-and-post lockdown periods were higher than the prescribed value, except during the lockdown period. Supplementary InformationThe online version contains supplementary material available at 10.1007/s10874-022-09440-5.

Health Risk Assessment on Exposure to PM2.5-bound PAHs from an Urban-industrial Area in Rayong City, Thailand

BACKGROUND: A city's industrial area's air quality has become a major priority. PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) are one of the most common pollutants in urban-industrial area, and can be linked to health problems.&#x0D; AIM: This study aims to 1) investigate PM2.5 and PAHs emitted from roadside area (RS) and industrial estate (IE) in Rayong city 2) assess the inhalation of PM2.5 and PAHs on the human health of the age group.&#x0D; METHODS: PM2.5-bound PAHs were investigated and thier carcinogenic risk was evalued in this study. PM2.5 samples were collected on quartz filters contained in a mini-volume air sampler and analyzed for PAHs by GC-MS.&#x0D; RESULTS: The average PM2.5 concentrations at RS and IE were 43.3±26.8 and 40.4±21.7 µg/m3, while the values of total PAHs in both sites were 1.68±1.53 and 1.34±1.22 ng/m3, respectively. However, it was found that the PM2.5 and PAHs values were not significantly different (p&gt;0.05). The results revealed that the individual lifetime cancer risk (Ric) of PM2.5 values for children and adults at both sites indicated acceptable cancer risk (10-6 to10-4). According to the incremental lifetime cancer risk (ILCR) values of PAHs for different age groups, exposure to PAHs in PM2.5 through the inhalation pathway was a negligible (&lt;10-6).&#x0D; CONCLUSION: As a result, the PM2.5 concentrations have substantial implications for Rayong city’s environmental management and protection, relating to car emissions and coal combustion.

DETERMINATION OF TERRESTRIAL RADIATION LEVEL OF OBITE, RIVERS STATE

Purpose: The perceived implication of increase in background radiation level of Obite Community due to inputs of hydrocarbon leakages and its emissions, lead to this research work, which investigated the background ionizing radiation levels of the area. &#x0D; Methodology: An in-situ background ionizing radiation measurement was carried out using radiation meter (Digilert 200) at an elevation of 1.0m above ground level with a Global Positioning System (G.P.S) for geographical location. &#x0D; Results: The background ionizing radiation (BIR) results obtained, varies from 0.007 to 0.024 (mR/hr) with a mean value of 0.013 (mR/hr). The values of Absorbed Dose Rate ranges from 60.9 to 208.0 nGy/hr with a mean value of 115.10±0.003 nGy/hr, which is higher than the recommended safe limit of 84.0 nGy/hr (UNCEAR, 2018). The Annual Effective Dose Equivalent (AEDE) varies from 0.009 to 0.38 mSv/yr with mean of 0.198 mSv/yr, is lower than the safe limit of 1.0 mSv/yr stipulated by ICRP (2003) and WHO (2008). The Excess Lifetime Cancer Risk (ELCR) values ranges from 0.32 to 0.09 x 101 with a mean of 0.062 x 10-1, is higher than the ICRP standard of 0.29 x 10-3 (ICRP, 2003).&#x0D; Conclusions: These results indicate an increase in cancer risk for individuals within the study area. The results were also summarized using the contour map to show various areas of high radiation distributions with interpretation of variability in concentration, in relation to geographical locations within the study area.

Source identification and toxicity apportionment of polycyclic aromatic hydrocarbons in surface soils in Beijing and Tianjin using a PMF-TEQ method.

Beijing and Tianjin are two of the largest cities in northern China with high population densities and highly developed manufacturing industries. In the past decade, some authors have reported their PAH concentrations in surface soils, identified their sources and quantitatively reported their health risks. However, the contributions of different PAH sources to their toxicity have not been reported thus far. In this study, we reviewed the PAH concentrations, contributions of different sources to the toxicity, and cancer risks in soils from different land use types found within Beijing and Tianjin from data gathered by 41 studies. The total PAH concentration varied in the range of 175.7–1989.0 ng g-1 with a higher median PAH concentration detected in urban soils (789.7 ng g-1), followed by suburban soils (647.3 ng g-1) and rural soils (390.8 ng g-1). Source identification using diagnostic ratios and principal component analysis (PCA) suggested that the PAHs in all three land use types mainly originated from biomass and coal combustion, vehicular emissions, and petrogenic processes with contributions varying from 13% to 62%. Furthermore, results from a positive matrix factorization (PMF) model suggested that vehicular emissions and coal combustion in urban soils, and the vehicular emissions, coal combustion and biomass combustion in suburban and rural soils dominated the total PAH concentrations (>85%). These results were consistent with those of the PCA model. Results of the additional toxicity apportionment performed using the PMF model suggested that vehicular emissions and coal combustion contributed the most to the toxic equivalent quantity for Benzo(a)Pyrene (BaPTEQ) and, by extension, to the carcinogenic potencies. The incremental lifetime cancer risk (ILCR) values suggested a low risk level for adults exposed to PAHs in the different land use types found within Beijing and Tianjin.