Seasonal variation and health risk assessment of organochlorine compounds in urban soils of Novi Sad, Serbia

Spatial pattern and compositional distribution of organochlorine pesticides in the black soil region of Shenyang

Organochlorine pesticides (OCPs) are persistent organic pollutants (POPs) prevalent in soils with carcinogenic, teratogenic and mutagenic hazards that are commonly found in soils and remain in the environment even though they have been banned. In order to fill the gap of fewer studies after the ban, soil samples were collected from 308 agricultural fields of cash crops and grain crops in the black soil area of Shenyang City (Liaozhong District, Faku County, Xinmin City and Kangping County) in this study. The aim was to determine, the use and distribution characteristics of OCPs in agricultural soils in the black soil region of Shenyang City. Compositional analysis showed that the detection rate of banned OCPs in agricultural soils was 71.75%, including contaminants such as technical dichloro-diphenyl-trichloroethane (DDT), chlordane and hexachlorobenzene (HCB), which were widely distributed in Liaozhong District, Faku County, Xinmin City and Kangping County, with 45.25% of the fields having compounded contamination of OCPs, and several areas were involved in the fresh inputs of contaminants such as technical DDT. Among them, Kangping County and Faku County are more seriously polluted, with 66.29% and 60.71% of OCPs exceeding the standard. Soil OCPs is more serious in cabbage and rice farmland among cash and food crop farmland. Based on Chinese policy on control, prevention and other pesticide management measures, it was concluded that the framework should be strengthened to prevent further illegal use of banned OCPs.

Organochlorine pesticide contamination of soils and dust from an urban environment in the Niger Delta of Nigeria

The concentrations, sources, and risk of twenty organochlorine pesticides (OCPs) in soils and dusts from a typical urban setting in the Niger Delta of Nigeria were examined. The Σ20 OCP concentrations (ng g-1) varied from 4.49 to 150 with an average value of 32.6 for soil, 4.67 to 21.5 with an average of 11.7 for indoor dust, and 1.6 to 96.7 with an average value of 23.5 for outdoor dust. The Σ20 OCP concentrations in these media were in the order: soil > outdoor dust > indoor dust, which was in contrast with the order of the detection frequency, i.e., indoor dust (95 to 100 %) > soil (60 to 90 %) > outdoor dust (30 to 80 %). The concentrations of the different OCP classes in these media followed the order: aldrin + dieldrin + endrin and its isomers (Drins) > chlordanes > dichlorodiphenyltrichloroethane (DDTs) > hexachlorocyclohexane (HCHs) > endosulfans for outdoor dust and soil, while that of the indoor dust followed the order: Drins > chlordanes > endosulfans > DDTs > HCHs. The cancer risk values for human exposure to OCPs in these sites exceeded 10-6 which indicates possible carcinogenic risks. The sources of OCPs in these media reflected both past use and recent inputs.

Evaluation of sediment quality for heavy metal(loid)s contamination and health risk assessment in the Gulf of Suez, Egypt

The Gulf of Suez faces challenges related to contamination, primarily due to industrial, tourism, and shipping activities along its shores. This study aims to record the distribution, concentration, and potential environmental and health risk impacts of heavy metal(loid)s (HMs) in 30 surface sediment samples collected from Ras Sidr coastline, Gulf of Suez. Various contamination and health indices were employed for this study. The average concentrations of HMs (μg/g) were ranked as follows: Fe (3472), Mn (103.3), V (10.41), As (7.94), Cr (6.00), Zn (5.31), Ni (2.94). The spatial distribution of HMs indicated an increase in Mn, Zn, As, and V levels toward the southern part of the study area, potentially linked to the proximity of manganese quarries and their metal association at Abu Zenima. Contamination indices revealed moderately severe enrichment with As, minor enrichment with Mn, and no enrichment for the remaining HMs. Multivariate analysis suggested a natural origin for Cr, Fe, Mn, Ni, Zn, and V, while As were likely anthropogenic. Values of hazard index (HI) for HMs in both adults and children followed the descending order of As > Fe > Cr > V > Mn > Ni > Zn. However, all HI values were below 1.0, indicating no significant non-carcinogenic risk for individuals along the Ras Sidr coastline. 19 samples exhibited lifetime cancer risk (LCR) values exceeding 1 × 10-4 for As in children, suggesting potential carcinogenic risks. LCR values for As in adults and Cr in adults and children ranged from 1 × 10-5 to less than 1 × 10-6, indicating acceptable or tolerable levels of carcinogenic risk and no significant threats to health.

Screening and optimization of interpolation methods for mapping soil-borne polychlorinated biphenyls

There is yet no scientific consensus, and for now, on how to choose the optimal interpolation method and its parameters for mapping soil-borne organic pollutants. Take the polychlorinated biphenyls (PCBs) for instance, we present the comparison of some classic interpolation methods using a high-resolution soil monitoring database. The results showed that empirical Bayesian kriging (EBK) has the highest accuracy for predicting the total PCB concentration, while root mean squared error (RMSE) in inverse distance weighting (IDW) is among the highest in these interpolation methods. The logarithmic transformation of non-normally distributed data contributed to enhance considerably the semivariogram for modeling in kriging interpolation. The increasing of search neighborhood reduced IDW's RMSE, but slightly affected in ordinary kriging (OK), while both of them resulted in over smooth of prediction map. The existence of outliers made the difference between two points increase sharply, and thereby weakening spatial autocorrelation and decreasing the accuracy. As predicted error increased continuously, the prediction accuracy of different interpolation methods reached unanimity gradually. The attempt of the assisted interpolation algorithm did not significantly improve the prediction accuracy of the IDW method. This study constructed a standardized workflow for interpolation, which could reduce human error to reach higher interpolation accuracy for mapping soil-borne PCBs.

Measurement of polychlorinated biphenyls in different high consumption canned foods, using the QuEChERS/GC-MS method

Polychlorinated biphenyls (PCBs) are organic pollutants containing chlorine, which can be carcinogenic to humans. The current research focused on the heart risk and determination of PCBs levels in canned foods using the modified QuEChERS (fast, easy, cheap, effective, resistant and safe) method and gas chromatograph/mass spectrometer (GC-MS) technique. In this study, LOD (limit of detection), LOQ (limit of quantification), and recovery ranged from 0.06 to 0.32, 0.18 to 1.07 ng/g, and 97.05 to 102.5 %, respectively. In canned foods, the highest median of PCBs was PCB 52 (0.27 ± 0.20 ng/g fat) and the lowest median were PCB 28 and 138 (not detected in samples). Also, the maximum median of PCB 28, 52, 101, 138, 153, and 180 were detected in eggplant samples (0.06 ng/g), haricot samples (0.49 ng/g), eggplant samples (0.36 ng/g), eggplant samples (0.19 ng/g), eggplant samples (0.11 ng/g) and lentiform samples (0.66 ng/g), respectively. The median PCBs levels of oral exposure were estimated to be in the range of 9.80E-07to 4.30E-05 ng/g.d for all population groups, which were meaningfully lesser than the Tolerable daily intake value. The Monte Carlo simulation (MCS) outcomes indicated that the rank order of PCBs in adults based on incremental lifetime cancer risk (ILCR) was Lentiform (7.05E-8) > canned fish (5.73E-8) > Eggplant (5.38E-8) > Haricot (4.33E-8) > pasta source (2.06E-8); and in children was Lentiform (3.40E-7) > canned fish (2.72E-7) > Eggplant (2.44E-7) > Haricot (2.06E-7) > pasta source (9.83E-8). The median values of the ILCR induced oral exposure for all groups were within safe limits (lower than 10-6). The heat map and multivariate principal component analysis (PCA) showed significantly different contributions of PCBs profile in samples as the PCA axis scores were correlated with the type of cans. Based on the obtained outcomes, it can be concluded that the PCBs of canned food do not potential health risks to Iranian consumers.

Investigation of organochlorine pesticides in the Wang Lake Wetland, China: Implications for environmental processes and risks

Wang Lake Wetland is an important habitat for many fish and migratory birds. To explore the effect of periodic hydrological changes on the transfer and ecological risk of OCPs in the multimedia system of the wetland, eight sampling sites were selected for collecting soil (SS), sediment (SD) and water, to acquire dissolved phase (DP) and suspended particulate matter (SPM) samples during low- and high-flow periods. The results indicated that OCPs are pervasive in the various media of Wang Lake Wetland, and there was a significant temporal variability in concentration of ∑23OCPs in the SPM samples. Several OCPs exist certain ecological risks to aquatic organisms, but higher level of OCPs do not always equal to higher ecological risk. The residues of OCPs are largely attributed to their historical use, but recent inputs of some of them are still non-ignorable. The relatively higher values of organic carbon normalized partition coefficient (KOC) for SPM-W (KOC(SPM-W)) were obtained, which reflected the more frequent exchange of OCPs in the SPM samples. The sediment of the Wang Lake Wetland is likely to be a sink for several OCPs with high n-octanol/water partition coefficient (KOW) (e.g., DDTs and its metabolites), and high-temperature and rainfall-driven changes may promote the migration of OCPs with low KOW to the DP.

Assessment of human health risks of toxic elements in coastal area between Al-Khafji and Al-Jubail, Saudi Arabia

The present work aims to document the distribution of toxic elements (TEs) and assess the human health risk posed by the TEs in the marine sediment of the Arabian Gulf, Saudi Arabia. The descending order of TE averages (μg/g) was as follows: Ni > Cr > V > Zn > Pb > Cu > As > Co. Based on the enrichment factor values, only minor enrichment for Pb, As, Cr, and Ni was noted. The hazard index (HI) values for the non-carcinogenic risk of the TEs were less than 1.0, and the lifetime cancer risk values for carcinogenic Pb, Cr, and As ranged between 2.96 × 10-8 and 5.44 × 10-5, indicating no significant health hazards for the inhabitants of the study area.

Inventory, source and health risk assessment of nitrated and parent PAHs in agricultural soils over a rural river in Southeast China

Nitrated polycyclic aromatic hydrocarbons (NPAHs) have become a concerning topic because of their widespread occurrence and carcinogenicity. However, studies on NPAHs in soils, especially in agricultural soils, are still limited. In this study, a systematic monitoring campaign of 15 NPAHs and 16 polycyclic aromatic hydrocarbons (PAHs) was performed in agricultural soils from the Taige Canal basin in 2018, which is a typical agricultural activity area of the Yangtze River Delta. The total concentration of NPAHs and PAHs ranged from 14.4 to 85.5 ng g^-1 and 118-1108 ng g^-1, respectively. Among the target analytes, 1,8-dinitropyrene and fluoranthene were the most predominant congeners accounting for 35.0% of ∑₁₅NPAHs and 17.2% of ∑₁₆PAHs, respectively. Four-ring NPAHs and PAHs were predominant, followed by three-ring NPAHs and PAHs. NPAHs and PAHs had a similar spatial distribution pattern with high concentrations in the northeastern Taige Canal basin. The soil mass inventory of ∑₁₆PAHs and ∑₁₅NPAHs was evaluated to be 31.7 and 2.55 metric tons, respectively. Total organic carbon had a significant impact on the distribution of PAHs in soils. The correlation between PAH congeners in agricultural soils was higher than that between NPAH congeners. Based on diagnostic ratios and principal component analysis-multiple linear regression model, vehicle exhaust emission, coal combustion, and biomass combustion were the predominant sources of these NPAHs and PAHs. According to the lifetime incremental carcinogenic risk model, the health risk posed by NPAHs and PAHs in agricultural soils of the Taige Canal basin was virtually negligible. The total health risk in soils of the Taige Canal basin to adults was slightly higher than that to children.

Degradation of four pesticides in five urban landscape soils: human and environmental health risk assessment

Pesticides are the most cost-effective means of pest control; however, the serious concern is about the non-target effects due to their extensive and intensive use in both agricultural and non-agricultural settings. The degradation rate constant (k) and half-life (DT₅₀) of four commonly used pesticides, glyphosate, 2,4-D, chlorothalonil and dimethoate were determined in five Australian urban landscape soils, with varying physicochemical characteristics, to assess their environmental and human health risks. The k values (day^-1) for the selected pesticides were inversely proportional to those of organic carbon (OC), silt, clay and Fe and Al oxides, and directly proportional to pH and sand content in soils. In contrast, the calculated values of DT₅₀ (days) of all the four pesticides in five soils positively correlated with OC, clay, silt and oxides of Fe and Al, whereas soil pH and sand content exhibited a negative correlation. The calculated values of environmental indices, GUS and LIX, for the selected pesticides indicate their potential portability into water bodies, affecting non-target organisms as well as food safety. The evaluation for human non-cancer risk of these pesticides, based on the calculated values of hazard quotient (HQ) and hazard index (HI), suggested that exposure of adults and children to soils, contaminated with 50% of initially applied concentrations, through ingestion, dermal and inhalation pathways might cause negligible to zero non-carcinogenic risks. The present data might help the stakeholders in applying recommended doses of pesticides in urban landscapes and regulatory bodies concerned in monitoring the overall environmental quality and implementing safeguard policies. Our study also clearly demonstrates the need for developing improved formulations and spraying technologies for pesticides to minimize human and environmental health risks.

Spatial characteristics, sources and exposure risk of polychlorinated biphenyls in dusts and soils from an urban environment in the Niger Delta of Nigeria

Chlorinated organic compounds, such as polychlorinated biphenyls (PCBs), are a threat to both humans and the environment because of their toxicity, persistence, and capacity for long-range atmospheric transport. The concentrations of 28 PCB congeners, including 12 dioxin-like and seven indicator PCBs, were investigated in soils, and indoor and outdoor dusts from Port Harcourt city, Nigeria, in order to evaluate the characteristic distribution patterns in these media, their sources, and possible risk. The PCB concentrations varied from 4.59 to 116 ng g^-1 for soils, and from 1.80 to 23.0 ng g^-1 and 2.73 to 57.4 ng g^-1 for indoor and outdoor dusts respectively. The sequence of PCB concentrations in these matrices was soil > outdoor dust > indoor dust. The composition of PCBs in these matrices indicated the prevalence of lower chlorinated PCBs in indoor and outdoor dusts, while the higher chlorinated congeners were dominant in soils. Di-PCBs were the predominant homologues in indoor dusts, while deca-PCBs were the most prevalent homologues in outdoor dusts and soils. The TEQ values of dioxin-like PCBs in 60 % of the soils, 100 % of the indoor dust, and 30 % of the outdoor dust were above the indicative value of 4 pg TEQ g^-1 established by the Canadian authority. The hazard index (HI) values for exposure of adults and children to PCBs in these media were mostly greater than one, while the total cancer risk (TCR) values exceeded the acceptable risk value of 10^-6, which indicate probable non-carcinogenic and carcinogenic risks resulting from exposure to PCBs in these media. Source analysis for PCBs in these matrices shows that they originated from diverse sources.

Comprehensive assessment of heavy elements and evaluation of potential human health risk in the urban environment: a case study from Novi Sad, Serbia

This study aimed to determine seasonal (summer vs. winter) and spatial distribution of the selected heavy elements (HEs) (As, Cd, Co, Cr, Cu, Ni, and Pb) in soil samples collected from a typical Central European town, Novi Sad, Serbia. The highest Pb concentrations were observed in summer because of intensive ground-flushing, whereas Cu had its highest concentration in winter, which may be attributed to traffic emissions. Source characterization and spatial distribution were carried out using cluster analysis (CA), principal component analysis (PCA), variogram calculation and theoretical model fitting, GIS-based geostatistical methods, and positive matrix factorization (PMF) data processing tools. Environmental impact of HEs found in different functional areas demonstrated that the quantified concentrations of Pb, As, Co, and Cu ranked soil as unpolluted to moderately polluted, while the presence of Co, Ni, and Cr classified urban soil as moderately polluted. Pollution load index (PLI) suggested a significant HEs enrichment while the new modified approach to Nemerow integrated risk index (NIRI) indicated high risk, being extreme for some selected locations. Machine learning classifiers were used for the first time to identify the differences between urban soil and dust samples in situations when simultaneous analysis of both matrices was carried out, as well as for temporal distribution (summer versus winter), based on the obtained concentration of HEs. Variogram calculation suggested that the pattern in spatial variability within the system emerged from the combined action of key structural factors (e.g., the parent soil material, landforms and topography, and climate) and random factors related to human activities. The estimated human health risk for two segments of the population revealed that ingestion is the primary route of exposure to HEs for children and adults.

A case study on the occurrence of polycyclic aromatic hydrocarbons in indoor dust of Serbian households: Distribution, source apportionment and health risk assessment

This study was conducted in order to obtain the first insight into the occurrence, potential sources, and health risks of polycyclic aromatic hydrocarbons (PAHs) in indoor dust. Samples (n = 47) were collected from households in four settlements in the northern Serbian province of Vojvodina. Total concentrations of 16 EPA priority PAHs in the dust samples varied from 140 to 8265 μg kg^-1. Mean and median values for all samples were 1825 and 1404 μg kg^-1, respectively. According to the international guidelines for indoor environment, PAH content can be regarded as normal (<500 μg kg^-1) for ∼6% of the samples, high (500-5000 μg kg^-1) for ∼87% of the samples, and very high (5000-50000 μg kg¹) for ∼6% of the samples. In all settlements, PAHs with 4 rings were the most prevalent (accounting for 40-53% of the total PAHs). They were followed by 3-ringed PAHs (29-40%), which indicates rather uniform PAH profiles in the analyzed dust. Based on diagnostic ratios, principal component analysis (PCA), and positive matrix factorization (PMF), pyrogenic sources, such as vehicle emissions and wood combustion were the dominant sources of PAHs in analyzed samples. Health risk assessment, which included incidental ingesting, inhaling and skin contact with PAHs in the analyzed dust, was evaluated by using the incremental lifetime cancer risk (ILCR) model. Median total ILCR was 3.88E-04 for children, and 3.73E-04 for adults. Results revealed that major contribution to quite high total ILCRs was brought by dermal contact and ingestion. Total cancer risk for indoor dust indicated that 85% of the studied locations exceeded 10-4. This implies risk of high concern, with potential adverse health effects. The results are valuable for future observation of PAHs in indoor environment. They are also useful for regional authorities who can use them to create policies which control sources of pollution.

Spatiotemporal distribution, source apportionment and risk assessment of typical hormones and phenolic endocrine disrupting chemicals in environmental and biological samples from the mariculture areas in the Pearl River Delta, China

The present work studied the levels, distribution, potential sources, ecological and human health risks of typical hormones and phenolic endocrine disrupting chemicals (EDCs) in the mariculture areas of the Pearl River Delta (PRD), China. The environmental levels of 11 hormones (6 estrogens, 4 progestogens, and 1 androgen) and 2 phenolic EDCs were quantified in various matrices including water, sediment, cultured fish and shellfish. Ultrahigh performance liquid chromatography-triple quadrupole tandem mass spectrometry analyses showed that all the 13 target compounds were detected in biotic samples, whereas 10 were detected in water and sediment, respectively. The total concentrations ranged from 35.06-364.53 ng/L in water and 6.31-29.30 ng/g in sediment, respectively. The average contaminant levels in shellfish (Ostrea gigas, Mytilus edulis and Mimachlamys nobilis) were significantly higher than those in fish (Culter alburnus, Ephippus orbis and Ephippus orbis). Source apportionment revealed that the pollution of hormones and phenolic EDCs in PRD mariculture areas was resulted from the combination of coastal anthropogenic discharges and mariculture activities. The hazard quotient values of the contaminants were all less than 1, implying no immediate human health risk. Overall, the present study is of great significance for scientific mariculture management, land-based pollution control, ecosystem protection, and safeguarding human health.

Seasonal Variation and Contamination Risk Assessment of Heavy Metals in Surface Sediment of an Estuary Alluvial Island in Eastern China

The heavy metal pollution of estuary wetlands caused by industrial and agricultural production activities has aroused widespread concern. The Hakanson Pollution index, Geo-accumulation index (I_geo) and Redundancy analysis were used to explore the seasonal variation and contamination risk of heavy metals in surface sediments. Results showed that the heavy metal concentrations were ranked in descending order: Cd > Cu > Zn > Pb > Cr. The analysis result of HPI and I_geo showed that there was a low level of heavy metal contamination both in summer and winter. Redundancy analysis showed that the correlation between heavy metals and physicochemical properties of sediment was significantly different in winter and summer. Our findings provide scientific support for the prevention of heavy metal pollution in estuary wetlands.

Risk assessment of chemical mixtures by benchmark dose-principle component analysis approach in occupational exposure

Mixtures of organic solvents are widely used in industrial processes. Risk assessment for chemical co-exposure has always been a challenge in past years. The present study aims to employ principle component analysis (PCA) to produce an entry for benchmark dose approximation in shoemakers based on the color vision effect. A total of 134 subjects consisting of 67 shoemakers and 67 staff workers were employed for Benchmark Dose (BMD) evaluation. Occupational exposure to benzene, toluene, xylene, and n-hexane was evaluated using NIOSH 1501 and OSHA ID-07 methods. The color vision effect was quantified using Lanthony D-15 desaturated test (D-15d). PCA was run for cumulative exposure dose (CED) of the solvents by MATLAB 2018. Finally, the lowest 95% confidence limit of the benchmark dose (BMDL) was determined using US EPA benchmark dose software (BMDS) version 3.2.1. The color confusion index (CCI) level in shoemakers increased from 1 to 1.15 by a median of 1.07. There was a significant difference in the CCI level (p value<0.0001) between exposed and control subjects. The first score of PCA was used as intake dose level (IDL) in solvents co-exposure. Using BMD analysis, the log-logistics model was fitted with a p-value> 0.1 and the lowest BMDL level. BMDL level was evaluated at 1.63, 10.25, 2.21, and 3.35 ppm for benzene, toluene, xylene, and n-hexane, respectively. The results showed a risk of color vision effect with co-exposure to solvents at different levels in the occupational exposure standards. In conclusion BMDL-PCA approach has been suggested for the risk assessment of chemical co-exposure.

Comprehensive characterization of PAHs profile in Serbian soils for conventional and organic production: potential sources and risk assessment

This study presents a comprehensive characterization of occurrence and levels of 16 polycyclic aromatic hydrocarbons (PAHs) in arable soils used for conventional and organic production in northern and central part of Serbia as well as cross-border region with Hungary. Furthermore, this study includes a characterization of PAH sources and carcinogenic/non-carcinogenic human health risk for PAHs accumulated in analysed arable soils. The total concentration of 16 PAHs varied between 55 and 4584 µg kg^-1 in agricultural soil used for conventional production and between 90 and 523 µg kg^-1 in agricultural soil used for organic production. High molecular weight (HMW) PAHs were dominant compounds with similar contribution in both soil types (86% and 80% in conventional and in organic soil, respectively). Principal component analysis and diagnostic ratios of selected PAHs were used for identification of PAH sources in the analysed soils. Additionally, positive matrix factorization was applied for quantitative assessment. The results indicated that the major sources of PAHs were vehicle emissions, biomass and wood combustion, accounting for ~ 93% of PAHs. Exposure of farmers assessed through carcinogenic (TCR) and non-carcinogenic (THQ) risk did not exceed the acceptable threshold (TCR < 10^-6 and THQ < 1). Oral ingestion was the main exposure route which accounted for 57% of TCR and 80% of THQ. It was followed by dermal contact. This investigation gives a valuable data insight into the PAHs presence in arable soils and reveals the absence of environmental and health risk. It also acknowledges the importance of comprehensive monitoring of these persistent pollutants.

Assessment of epigenotoxic profiles of Dongjiang River: A comprehensive of chemical analysis, in vitro bioassay and in silico approach

This research explored the occurrence, epigenetic toxic profiling and main toxic pollutants of POPs in surface water of Dongjiang River, southern China. The concentrations of selected POPs including polycyclic aromatic hydrocarbons (PAHs), endocrine disrupting chemicals (EDCs), phthalate esters (PAEs) and polybrominated diphenyl ethers (PBDEs) of surface water from 18 sites were investigated. ∑₁₆PAHs and ∑₄EDCs were at a moderate level, while ∑₆PAEs and ∑₆PBDEs had low pollution levels. PAHs, EDCs and PAEs showed higher concentrations in dry season than those in wet season, and the loading of selected POPs in tributaries was higher than those in mainstream due to intensive manufactures and lower runoff volume. Moreover, activities of DNA methyltransferase (DNMT)1, histone deacetylase (HDAC2, HDAC8) were confirmed to be sensitive indicators for epigenetic toxicity. The DNMT1-mediated epigenetic equivalency toxicity of organic extracts in Dongjiang River were more serious than those of HDAC2 and HDAC8. Correlation analysis shown binding affinity between POPs and DNMT1, HDAC2 and HDAC8 could be regarded as toxic equivalency factors. Risk assessment suggested that 4-nonylphenol and bisphenol A were the largest contributors to epigenetic risk. This study is the first attempt to quantify epigenetic toxicity and epigenetic risk evaluation of river water.

Urban street dust in the Middle East oldest oil refinery zone: Oxidative potential, source apportionment، and health risk assessment of potentially toxic elements

The current study is the intented to investigate the intensity of pollution, source characterization, oxidative potential, and human health risks of fourteen potentially toxic elements in the street dust of the Middle East oldest oil refinery zone. Thirty five street dust samples were collected from various regions in Abadan and Khorramshahr cities. The mean concentration of As, Mo, Cu, Pb, Hg, Zn, Cd, and Sb in Abadan street dust were 5.55, 3.39, 83.68, 49.82, 4493.54, 281.24, 1.15,and 1.17, while in Khorramshahr As, Mo, Cu, Pb, Hg, Zn, Cd, and Sb were.14, 2.58, 74.35, 56.50, 0.74, 214.26, 0.62, and 1.18, respectively. The concentration of these elements in both cities is higher than the local background values. Potential ecological risk index and pollution load index at all stations of both cities are greater than 1, indicating a high pollution load in the study area. Calculated enrichment factor showed high enrichment of Hg, Sb, Cd, Mo, Cu, Pb, and Zn in both areas. Of particular concern is the enrichment factor for mercury which proved to be 3370.54 ppb in the vicinity of the petrochemical unit in Abadan city (EF > 40). The results of positive matrix factorization receptor model together with geochemical maps and multivariate statistics indicated that industrial activities (especially petrochemical industries) are responsible for Hg, Cu, and Zn pollution, while exhaust emissions are responsible for Mo, Pb, Cd, and Sb, and natural sources for Al, Cr, Mn, Fe, Co, and Ni. The percentage of OP^AA in the region ranged from 15.1 to 26.4 and OP^GSH ranged from 9.5 to 24.4. The percentage of OP_TOTAL/μg (OP^AA/μg + OP^GSH/μg) values varied between 0.6 and 1. The health risk evaluation models indicated that specific attention should be paid to Hg, Cd, Pb, and Zn and that the higher oxidative potential of street dust recovered from polluted locations is also a matter of concern in Abadan and Khorramshahr Cities.

Health risk assessment in urban parks soils contaminated by metals, Rio Grande city (Brazil) case study

Soils and artificial surfaces of urban parks can be contaminated by toxic substances and offer risk to the human health, especially to children. Rio Grande city, southern Brazil, is a peculiar site from the point of view of environmental contamination, since the current levels of contamination reflect an accumulation of different polluting sources started in the 18th century up to the urban and industrial sources of the present. The history of Hg contamination refers to the use of Hg salts in textile activities in the 18th century and the consequent use of contaminated sediments to land urban areas. The current contamination involves metals such as Cu, Ni, Pb and Zn is related to the high degree of urbanization in the city, as well as the petrochemical and fertilizer industry. The study aimed to achieve a human health risk assessment of urban parks soils, specifically for Cu, Hg, Ni, Pb and Zn. To carry out the risk assessment using the USEPA model, three urban parks with a history of contamination were studied, using different soil exposure pathways (oral, dermal and inhalation) in the carcinogenic (Ni and Pb) and non-carcinogenic (Cu, Hg, Ni, Pb and Zn) scenarios for children and adults. The non-carcinogenic risk of Pb was found in the three urban parks studied, for children and Hg in two urban parks. Pb and Ni showed no carcinogenic risk. Even so, the high non-carcinogenic risk of Hg and Pb showed that the contamination of the past and the present are found in the urban parks of Rio Grande city, putting the health of children who use these collective spaces at risk.

Heavy metal and pesticide levels in dairy products: Evaluation of human health risk

Cattle milk's health benefits can be compromised by the presence of contaminants. The levels of cadmium, copper, lead and zinc, and residues of dichlorodiphenyldichloroethylene (DDE), dichlorodiphenyldichloroethane (DDD), dichlorodiphenyltrichloroethane (DDT) were determined in soil, milk and cheese samples collected from cow farms from 3 Romanian areas with industrial and agriculture tradition. A new methodology was applied for the determination of the corrected estimated daily intake (cEDI) corresponding to the aggregate dietary exposure. For the risk assessment, we calculated the source hazard quotient (HQs) for each contaminant and the adversity specific hazard index (HIA). Cadmium, copper, lead and zinc, and the sum of DDT levels in soil samples were below maximum residue levels (MRLs). The MRLs of lead and DDD were exceeded in milk and cheese samples from all the 3 areas. The MRLs of copper and zinc were exceeded in cheese samples from area 2 and 3. HQs >10 for lead indicates increased risk, while HQ > 1 for copper and sum of DDT indicates moderate risk for both milk and cheese. By calculating the HI_A, we identified a moderate and increase risk for nephrotoxicity, hepatotoxicity, hematotoxicity, cardiotoxicity and reproduction toxicity after consumption of the dairy products from the 3 areas.

Congener-specific composition of polychlorinated biphenyls (PCBs) in soil-air partitioning and the associated health risks

The recent changes in the compositions of polychlorinated biphenyls (PCBs) after their restriction for 40 years may have various effects on human health. In order to characterize the congener-specific compositions of PCBs in the soil-air process and assess the associated human health risks, soil and air samples were simultaneously collected in winter and summer at two different functional locations. Homologue patterns suggest that long-range atmospheric transport might be the major source of soil and air residues of PCBs. The net deposition from air to soil was overwhelming for most PCB congeners. Variations in the occurrence and the homologue patterns of PCBs between the soil and air interface depended on chemical volatility, soil organic matter (OM) content, ambient temperature, topographical condition and atmospheric transport. Dioxin-like PCBs accounted for 11.0-70.3% and 2.31-54.8% of total PCB residues in soil and air, respectively. Non-carcinogenic and carcinogenic risks associated with exposure to soil and air PCBs were also estimated. Different PCB congeners showed different health effects, with the highest contribution from PCB-26. Additionally, the non-carcinogenic risk levels of PCBs were enhanced, while the carcinogenic risk levels decreased during the soil-air exchange process of PCBs with time. Our results highlight the soil-air interaction of PCBs in predicting their potential human exposure health risks.

Occurrence, seasonal variety of organochlorine compounds in street dust of Novi Sad, Serbia, and its implication for risk assessment

The paper presents a study of organochlorine compounds in street dust, an often forgotten aspect of urban environmental pollution. Six different polychlorinated biphenyls (PCBs) and eighteen organochlorine pesticides (OCPs) were monitored in terms of levels, distribution, seasonal variation and health risks. Street dust samples were collected from fifteen urban locations in Novi Sad including schools, recreational areas, residential and industrial zones. Street dust concentration of PCBs ranged from less than the limit of detection (<LOD) to 12.1 ng g^-1 (mean = 0.58 ng g^-1) in summer and from <LOD to 3.82 ng g^-1 (mean = 0.45 ng g^-1) in winter. Among the investigated OCPs, only dichlorodiphenyltrichloroethanes (DDTs) were detected - their concentration varied from <LOD to 34.7 ng g^-1 (mean = 6.2 ng g^-1 and median = 1.4 ng g^-1) in summer to <LOD to 50.5 ng g^-1 (mean = 7.1 ng g^-1 and median = 2.0 ng g^-1) in winter. Principal component analysis indicated a positive correlation among PCB 101, PCB 153 and pH as well as between PCB 138 and organic matter. Regression analysis revealed that distribution trends of DDTs between the soil and street dust samples are significantly correlated in the recreational areas. The average level of total lifetime carcinogenic risk (TLCR) for PCBs (3.7 × 10^-9) and DDTs (3.6 × 10^-9) found in Novi Sad street dust samples were well below the unacceptable level of 10^-6, indicating that the lifetime cancer risk was acceptable. It was also found that the seasonal variations were not significant.

Seasonal occurrence and cancer risk assessment of polycyclic aromatic hydrocarbons in street dust from the Novi Sad city, Serbia

This is the first investigation that identified seasonal occurrence, distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) in 60 street dust samples collected within urban zone of Novi Sad, the second largest city in Serbia. The obtained results were further used for comprehensive assessment of carcinogenic risk of Serbian inhabitants exposed to PAHs present in street dust by the incremental lifetime cancer risk method. The total level of 16 PAHs ranged between 35 μg kg^-1 and 2422 μg kg^-1 in samples taken in summer and between 35 μg kg^-1 and 587 μg kg^-1 in samples taken in winter. In both seasons, 4-ring PAHs were the most dominant compounds and high molecular weight (HMW) PAHs had similar contribution (55% in summer and 65% in winter). The highest content was determined for fluoranthene (Fly) in both seasons (597 μg kg^-1 in winter, 301 μg kg^-1 in summer). The PAHs source apportionment was analyzed by principal component analysis (PCA) and diagnostic ratios, and combustion of petroleum seemed to be the main sources of the PAHs in street dust. The cancer risk level for children and adult were comparable for dermal contact and by ingestion, and ranged from 10^-6 to 10^-4 indicating a potential risk. Additionally, the total incremental life time cancer risk (ILCR) was assessed for children and adult population taking into account three possible exposure routs and the median total cancer risk was ˃10^-5, with 7% of the samples having the risk ˃10^-4 that should be considered of high concern with potential health problem. These results are the first of this kind for the whole Serbia and the Western Balkan region and can be considered as the base line for future research.

Survey on the micro-pollutants presence in surface water system of northern Serbia and environmental and health risk assessment

This study demonstrates the occurrence of 940 organic micro-pollutants in surface water of four rivers, one irrigation canal system, and two lakes in Vojvodina Province, the northern part of Serbia, summing in total eighteen samples. The number of detected chemicals ranged from 22 to 84, with 127 micro-pollutants detected at least once, representing 13% of the studied substances. The targeted compounds include n-alkanes, sterols, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides polychlorinated biphenyls, pesticides, pharmaceutical active compounds, industrial chemicals, plasticizers, etc. Among the analysed compounds, sterols were the most dominant with maximum quantified concentrations. The substances which were quantified with frequency over 50% were two PAHs (2-methylnaphthalene, benzo(ghi)perylene), five sterols (cholesterol, cholestanol, stigmasterol, fucosterol, beta-sitosterol), three pharmaceuticals and personal care products (L-menthol, diethyltoluamide, caffeine), and ten household chemicals (4-tert-octylphenol, dimethyl phthalate, methyl palmitate, phenylethyl alcohol, 1-nonanol, alpha-terpineol, 2-phenoxy-ethanol, methyl myristate, acetophenone, and 2-ethyl-1-hexanol). The list of priority substances under the European Union Directive 2013/39/EU includes 49 priority substances (PSs) out of which 34 were analysed. Among these, eleven PSs were quantified, and only two compounds (fluoranthene and benzo (a) pyrene) exceeded EU Environmental Quality Standards targeted values. The obtained results were compared with the previously published data that dealt with the same targeted number of micro-pollutants in sediment samples. This revealed connections between the same sampling locations. Environmental risk assessment showed the existence of potential ecological risk as 72% of the obtained values for the ecological hazard index (HI) at investigated locations were higher that the targeted value (HI > 1). Estimated values for hazard quotient (HQ) and hazard index (HI) for non-carcinogenic risk were lower than the targeted value, indicating no non-carcinogenic risk through dermal contact and non-intentional ingestion of water. Estimated values for cancer risk were all below 1 × 10^-6, which is not considered to pose significant human health risk.

Seasonal, spatial variations and risk assessment of heavy elements in street dust from Novi Sad, Serbia

This is the first study carried out to determine the levels, spatial and temporal variations and risk indices of street dust in Serbia. Sixty street dust samples representing four functional areas: school, recreational, residential and industrial were collected from Novi Sad during summer and winter. The purpose was to obtain the concentration of seven heavy elements, evaluate the possible sources and degree of environmental pollution and human health risks. The average concentration of As, Cd, Co, Cr, Cu, Ni and Pb (mg/kg) during winter was: 7.96, 0.40, 7.73, 12.1, 57.6, 14.0 and 70.6, while in summer it was: 1.88, 0.54, 4.31, 60.1, 42.7, 28.1, and 62.5, respectively. Interpolation method together with the correlation matrix and the results of multivariate statistics supported anthropogenic origin of Pb, Cr and Cu, natural origin of Ni, Cd and As and mix origin of Co. Pollution indices such as geoaccumulation index (I_geo) indicated existence of unpolluted to extreme risk regarding to environmental pollution. Moreover, the potential pollution index (Er) showed low (Pb) to moderate (Ni) risk while potential risk index (RI) and modified potential risk index (mRI) indicated considerable and very high risks. Health risk assessment showed no non-carcinogenic risk of heavy elements for adults and children.

Micro-pollutants in sediment samples in the middle Danube region, Serbia: occurrence and risk assessment

This is the first comprehensive study on the occurrence of 940 semi-volatile organic compounds including sterols, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pesticides, plasticizers, and other emerging compounds in 10 river and canal sediments collected in northern Serbia. For quantification of investigated compounds GC-MS-MS (selected reaction monitoring) and GC-MS (using both selected ion monitoring and total ion monitoring) methods were used. The number of detected compounds was in the range of 85-117, while the sum of the concentrations varied from 959 μg/kg dry-wt to 84,445 μg/kg dry-wt. Sterols were quantified with high frequency in nearly 100% of investigated samples suggesting that the studied rivers and canals have been contaminated by sewage. Regarding persistent organic compounds, p,p'-DDE, p,p'-DDD, and o,p'-DDT were the dominant members of organochlorine pesticides (OCPs). The concentration range of 11 quantified pesticides of 452 analyzed was from 0.564 to 61.6 μg/kg dry-wt, while the concentration range of 47 quantified PCBs of 90 analyzed was from 0.928 to 32.1 μg/kg dry-wt. OCPs (DDE, DDD, and γ-HCH) and several PAHs (fluoranthene, pyrene, phenanthrene, chrysene, benzo(a)anthracene, benzo(a)pyrene) exceeded the maximum values of the sediment quality guidelines. Contents of domestic compounds comprise a large proportion of the total contaminant concentration. Overall, the study reveals that river sediments in Vojvodina Province were moderately polluted mainly by domestic wastewater. The toxic equivalent quantity (TEQ) relative to benzo(a)pyrene and 2,3,7,8-tetrachlorodibenzodioxin for seven carcinogenic PAHs and six quantified dioxin-like PCBs ranged from 3.59 to 103 μg TEQ/kg and from 0.001 × 10^-3 to 2.10 × 10^-3 μg TEQ/kg, respectively, and were in the range or lower than the literature published data.