Occurrence of heavy elements in street dust from sub/urban zone of Tianjin: pollution characteristics and health risk assessment

Contamination levels, influencing factors, and risk assessment of polybrominated diphenyl ethers in house dust of northern Serbia

Polybrominated diphenyl ethers (PBDEs) are a group of compounds that, due to their applications, are considered mainly indoor contaminants. To obtain the first information about the presence of PBDEs in Serbia, dust samples (n = 50) were collected in settlements in the northern Serbian province of Vojvodina. The selected/target congeners (BDE-28, 47, 99, 100, 153, 154, and 183) were extracted from house dust by microwave-assisted extraction technique, and purified extracts were analyzed on a dual-column gas chromatograph with micro-electron capture detectors. A wide range of ΣPBDEs was detected (0.295 to 394 ng g-1 dust), which reflects large differences in contamination among the examined homes. For the majority of samples (72%), ΣPBDEs were lower than 5 ng g-1 indicating that people living in Vojvodina province are exposed to low concentrations of PBDEs present in their households. Based on principal component analysis (PCA), balcony areas and age of the house positively correlate with the PBDE congeners with higher detection frequencies (≥ 50%), namely, with BDE-99, BDE-153, and BDE-183. Statistically significant positive correlation (p < 0.01) was obtained for BDE-99 and the number of household's members. Estimated daily intakes (EDItot) were calculated for ingestion and dermal absorption of dust for two age groups-adults and toddlers. These are the first data on PBDE status in the area of the Western Balkan, and the health risk assessment indicates that PBDE levels obtained in household dust do not pose a risk for human health.

Toward an interdisciplinary approach to assess the adverse health effects of dust-containing polycyclic aromatic hydrocarbons (PAHs) and metal(loid)s on preschool children

Settled dust can function as a pollutant sink for compounds, such as polycyclic aromatic hydrocarbons (PAHs) and metal(loid)s (MMs), which may lead to health issues. Thus, dust represents a hazard specifically for young children, because of their vulnerability and hand-to-mouth behavior favoring dust ingestion. The aim of the present study was to explore the influence of the season and the microenvironment on the concentrations of 15 PAHs and 17 MMs in indoor and outdoor settled dust in three preschools (suburban, urban, and industrial). Second, the potential sources and health risks among children associated with dust PAHs and MMs were assessed. Third, domestic factors (risk perception, knowledge and parental style) were described to explore protective parental behaviors toward dust hazards. The suburban preschool had the lowest concentrations of dust PAHs and MMs, while the industrial and urban preschools had higher but similar concentrations. Seasonal tendencies were not clearly observed. Indoor dusts reflected the outdoor environment, even if specific indoor sources were noted. Source analysis indicated mainly vehicular emissions, material release, and pyrogenic or industrial sources. The non-cancer health risks were non-existent, but potential cancer health risks (between 1.10-6 and 1.10-4) occurred at all sampling locations. Notably, the highest cancer risk was observed in a playground area (>1.10-4) and material release should be further addressed. Whereas we assessed higher risk indoors, parents perceived a higher risk in the open-air environment and at the preschool than at home. They also perceived a lower risk for their own children, revealing an optimism bias, which reduces parental anxiety.

A comprehensive review on pollution status and associated health risk assessment of human exposure to selected heavy metals in road dust across different cities of the world

In order to expound on the present situation and potential risk of road dust heavy metals in major cities, a total of 114 literatures mainly over the past two decades, involving more than 5000 sampling sites in 61 cities of 21 countries, were screened through the collection and analysis of research papers. The concentration, sources, distribution, health risk, sample collection, and analytical methods of heavy metal research on road dust in cities around the world are summarized. The results show that Cd, Zn, and Cu in many urban road dusts in the world are higher than the grade II of the Chinese maximum allowable concentration of potentially toxic elements in the soil. Geo-accumulation index values show that Pb > Cd > Zn > Cu had the highest contamination levels. Hazard index assessment indicates Pb and Cr had the highest potential health risk, especially for children in which ingestion was found as the main exposure pathway. Moreover, through comparative analysis, it is found that some pollutants are higher in developed and industrialized cities and transport (53%) followed by industrial emissions (35%) provide the major contributions to the sources of heavy metals.

Heavy element contents of vegetables and health-risk assessment in China

This study analyzed five heavy elements (HEs), including cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), and arsenic (As), in fresh vegetables (i.e., legume, rhizome and potato, gourd, bulb, solanaceous fruit, leafy, and brassica; total: 7214) collected from 31 provinces in China from 2016 to the first half of 2017. By analyzing the concentration level of the five HEs in seven regions (the Northeast, North China, East China, South China, Central China, the Northwest, and the Southwest), except for As, average HEs concentrations were higher in the Southwest than that in the other six regions. According to the maximum permissible limit (MPL), the highest rate of HEs concentration above the MPL was found in the Southwest (11.038%). Analysis of variance (ANOVA) showed varying degrees of variability between regions and categories. By using principal component analysis (PCA), it was found that two principal components account for 73.79% of the total variance in the data. Together with hierarchical cluster analysis (HCA), concluded that Tibet was significantly different from the other 30 provinces. By calculating estimated daily intake (EDI) and the target hazard quotient (THQ), the EDI of Cr in the Southwest was the highest, with results of 1.2119 μg/kg/day for children and 0.8073 μg/kg/day for adults. North China had the highest total target hazard quotient (TTHQ) for HEs in vegetables ingested by children, with a result of 0.933.

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.

Seasonal source identification and source-specific health risk assessment of pollutants in road dust

Humans who are exposed to metals in road dust may have potential health risks through touching, ingesting, and inhaling the suspended road dust. There were limited studies to link seasonal emission sources to health risks from metals in road dust. In this study, metals in road dust from different functional areas were seasonally monitored. The contributions of the pollutant sources in study areas varied with seasons. By combining the source apportionment model (PMF), road dust emission model, and health risk models (HI: hazard index and ILCR: incremental lifetime carcinogenic risk), industrial and construction activity was identified as the crucial source of both the pollutants in road dust (29-47%), and the HI for adults (27-45%) and children (41-50%) in different seasons. The traffic non-exhaust emission dominated in the carcinogenic risks for children in spring (45%) and summer (36%). Factors such as seasons, particle size, metal bioavailability, human exposure time, and exposure area were all taken into consideration to avoid overestimating or underestimating health risks. The carcinogenic risks for children (1.6 E-06) and adults (2.8 E-06) exposed to Cr both exceed the minimum threshold (10^-6). It means that the potential risks were acceptable but could not be completely neglected. Measured metals mainly posed hazard to human health through ingestion route. Pb and Mn, Fe and Mn were the main harmful elements that induced non-carcinogenic risks for adults and children, respectively. Effectively identifying the source-specific health risks in different seasons will help in the formulation of adaptive strategies to diminish the potential risks.

Ecological and human health risks from pseudo-total and bio-accessible metals in street dusts

Street dust samples were collected from industrial and commercial cities (Jamshedpur and Ranchi during monsoon and post-monsoon seasons) for detecting the levels of Cr, Cd, Cu, Ni, Pb, Zn, As, Co, Al, and Mn. The industrial city recorded higher metal concentrations compared to commercial. Similar trend of pseudo-total metal concentrations was observed in both the seasons at industrial city (Al > Mn > Zn > Cr > Pb > Cu > Ni > Cd) and only monsoon season at commercial city (Al > Mn > Zn > Cu > Cr > Pb > Ni > Cd). Zn > Cd was the most bioaccessible metal throughout the cities (monsoon and post-monsoon). The geochemical parameters (Igeo, EF, CF) were highest for Cd and lowest for Ni (both cities for the two seasons). Pollution Load Indices (PLI zone) were highest during the post-monsoon season in the industrial city. The highest carcinogenic risk was posed by Cr ranging from 1.87E-05 to 4.80E-05, in both the cities through ingestion and inhalation pathways. Children were found at higher risks, while the bioaccessible fractions posed neither carcinogenic nor non-carcinogenic threats to the population. Principal component analysis and correlation analysis indicated the influence of vehicular and industrial emissions, especially steel industry and coal-based thermal power plants as the major source of metals in street-dust. The outcomes of this work will be useful in providing baseline information of pollution along with their consequent environmental and human health risks of Jharkhand state.

Contamination, source attribution, and potential health risks of heavy metals in street dust of a metropolitan area in Southern Vietnam

This study investigates distribution, pollution indices, and potential risk assessment for human health and ecology of eight heavy metals in twenty-five street dust samples collected from metropolitan area-Ho Chi Minh City, Vietnam. Results showed that Zn was of the highest concentration (466.4 ± 236.5 mg/kg), followed by Mn (393.9 ± 93.2 mg/kg), Cu (153.7 ± 64.7 mg/kg), Cr (102.4 ± 50.5 mg/kg), Pb (49.6 ± 21.4 mg/kg), Ni (36.2 ± 15.4 mg/kg), Co (7.9 ± 1.9 mg/kg), and Cd (0.5 ± 0.5 mg/kg). The principal component analysis revealed that three sources of heavy metals measured in street dust include vehicular activities (32.38%), mixed source of vehicular and residential activities (26.72%), and mixture of industrial and natural sources (20.23%). The geo-accumulation index values showed levels of non-pollution to moderately pollution for Mn and Co; moderately pollution for Ni; moderately to strongly pollution for Cd, Cr, and Pb; and strongly pollution for Cu and Zn. The potential ecological risk values of all sampling sites were close to the high-risk category. Zn (28.9%), Cu (25.4%), and Mn (24.4%) dominantly contributed to the ecological risk. For non-carcinogenic risk, the hazard quotient values for both children and adults were within a safety level. For carcinogenic risk, the TCR_Children was about 3 times higher than TCR_Adults, but still within a tolerable limit (1 × 10^-6 to 1 × 10^-4) of cancer risk. Cr was a major contribution to potential risks in humans. Such studies on heavy metal in street dust are crucial but are still limited in Vietnam/or metropolitan area in Southeast Asia. Therefore, this study can fill the information gap about heavy metal contaminated street dust in a metropolitan area of Vietnam.

Pollution status and health risk caused by heavy elements in the flooded soil and vegetables from typical agricultural region in Vojvodina Province, Serbia

The investigation conducted in the Vojvodina Province, as a typical European and one of the biggest agricultural regions in the Balkans, offers the research methodology that could be used for any non/flooded agricultural region. The flood impact on heavy elements (HE) content in the flooded arable soil (n = 16) in relation to the control soil (n = 16) was examined, as well as their accumulation in the most often cultivated vegetables (n = 96) in the studied area. Results revealed that the flood did not significantly change the pseudo total HEs concentration in the soil as well as their amounts accumulated in different soil fractions. In both soils, only the average content of Ni exceeded the maximum permissible values set by Serbian soil quality standard which is in line with the Dutch standard. In comparison with the background values, notable enrichment is found for most of analyzed elements in both soils. Soil pollution status was assessed through several indices indicating that contamination range was in the domain from a moderate to a highly polluted. The principal component analysis demonstrated that soil contamination was probably originated from agricultural/anthropogenic activities (Cd, Cu, As, Pb), apart from Ni, Cr, and Co which came from natural weathering of the parent material. Carcinogenic and non-carcinogenic risks of selected HEs for Serbian population in the investigated region were below the threshold values. The average levels of Pb in investigated potato and carrot samples were higher than the maximum allowable concentrations established by EU/Serbian regulation. The total hazard quotients (THQ) of HEs through intake of analyzed vegetables were below the safe threshold (˂ 1), suggesting the absence of adverse health effects.

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.

Pollution effect assessment of industrial activities on potentially toxic metal distribution in windowsill dust and surface soil in central China

Boundaries between industrial and urban areas in developing countries are not clearly defined, but pollution effect assessment of industrial activities on potentially toxic metal (PTM) distribution in these areas has rarely been investigated. Fifteen villages and eight communities surrounding the industrial areas from Anyang, China, were chosen as research objects in this study. A total of 78 windowsill dust and 78 surface soil samples were collected to determine the pollution levels, spatial distribution and risk indices of nine PTMs. PTM concentrations (expect Cr, Mn and Ni in surface soil) in the surveyed region were higher than the local soil background values. Amongst these PTMs, serious Cd and As pollution was discovered, and Cd and As in windowsill dust and surface soil exceeded the background value by 73.00 and 9.59, 9.74 and 10.92 times, respectively. Compared with the I_geo in surface soil, a large degree of variation in I_geo for the different PTMs was found in windowsill dust. The interpolated spatial distribution of dust Cr, Zn, Pb, Cd and soil Mn, Ni and Cu had a gradually decreasing pollution trend from the south to the north due to the prevailing wind directions in winter in the study area. Results of multivariate statistics reflected that industrial production and traffic emission affected the concentration of PTMs in windowsill dust and surface soil. The non-carcinogenic risks for children (soil: 12.4; dust: 19.2) were larger than those for adults (soil: 1.02; dust: 1.51). This finding suggested that industrial activities caused serious harm to the residents around industrial areas.

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.

Pollution status and human health risk assessments of selected heavy metals in urban dust of 16 cities in Iran

Urban dust contamination is becoming progressively noticeable, and heavy metals are primary pollutants in urban environments. The contamination of heavy metals in urban dust has been affecting the urban citizens due to their adverse effects on human health, and understanding their effects is a crucial stage for its management. This study is a review of the reports of heavy metal pollution in urban dust of 16 cities in Iran, aimed at determining pollution status and health risk calculation on the nationwide scale, using geo-accumulation index (Igeo), potential ecological risk index (PER), and health risk assessment model. Six toxic elements, namely cadmium, copper, chromium, nickel, lead, and zinc were evaluated in this study. The results presented that the total heavy metal concentrations in the studied cities decreased in the sequences of Zn > Cu > Pb > Ni > Cr > Cd. The average concentrations of Cd, Cu, Ni, Pb, and Zn in the studied cities exceeded the Iran Standard Soil limits for residential areas. The mean levels of studied heavy metals for cities was in the order of Kermanshah > Tehran > Tabriz > Rafsanjan > Hamedan > Isfahan > Mashhad > Ahvaz > Abadan > Kerman > Bushehr > Kashan > Shiraz > Zahedan > Masjed-e-Soleiman > Arak. The Results of Igeo revealed that the pollution levels of Cd, Cu, Pb, Ni, Cr, and Zn in the studied cities ranged from unpolluted to moderate pollution categorizations. The mean potential ecological risk factor (Eⁱ_r) values were below (E^r_i < 40), showing a low ecological risk level. Also, Eⁱ_r values for all cities showed that Cd, Pb, and Cr had the highest ecological risks than other heavy metals. However, the total potential ecological risk index (RI) values for studied cities were 172.1, showing a moderate ecological risk level. Human health risk assessment evaluation showed that in contrast to adults, children have more possible health risks (non-carcinogenic). Among the multiple pathways of exposure, the ingestion pathway was the most important exposure for both groups of population, followed by skin exposure and then breathing exposure. Total hazard index (HI) values among three exposure routes, were less than harmless level (HI < 1), displaying that there was not a non-carcinogenic risk for both groups of population. Cancer risk (CR) study exhibited that the potential risk of cancer decreases in the order of chromium > nickel > cadmium. The CR ranks of chromium, nickel, and cadmium were less than the maximum permissible level, presented an insignificant carcinogenic risk.