Seasonal concentrations, contamination levels, and health risk assessment of arsenic and heavy metals in the suspended particulate matter from an urban household environment in a metropolitan city, Beijing, China

Geochemical elements in suspended particulate matter of Ensenada de La Paz Lagoon, Baja California Peninsula, Mexico: Sources, distribution, mass balance and ecotoxicological risks

The present study aimed to evaluate multi-element concentrations (Al, As, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sr) in suspended particulate material (SPM) collected from Ensenada de La Paz (ELP) lagoon, Baja California Sur, Mexico in two different periods (September and May) to comprehend their origin, geochemical behavior, mass transfer and associated ecotoxicological risks. The 24 hr variation coefficient of volumetric SPM levels were found to be 51.7% in September and 40.5% in May, signifying the effects of oceanic waters. The calculated enrichment factor (EF) values for all the studied elements were of higher magnitude because of the high surface area and oxide nature of SPM, and in this study, Mo had the highest EF of 46.77 probably due to its origin from continental weathering. From the ecotoxicological perspective, the integrated toxic risk index revealed low toxic risk to the benthic community. However, the mean-ERM-Quotient calculated using the particulate concentrations of As, Cd, Cr, Cu, Ni, Pb indicated 9% probability of toxicity to biota. The comprehensive geochemical and ecotoxicological assessment of particulate metal concentrations in the ELP lagoon signify low to moderate contamination.

Association of PM2.5 Components with Acceleration of Aging: Moderating Role of Sex Hormones

Fine particulate matter (PM_2.5) has been linked to aging risk, and a lack of knowledge about the relationships between PM_2.5 components and aging risk impeded the development of healthy aging. Participants were recruited through a multicenter cross-sectional study in the Beijing-Tianjin-Hebei region in China. Middle-age and older males and menopausal women completed the collection of basic information, blood samples, and clinical examinations. The biological age was estimated by Klemera-Doubal method (KDM) algorithms based on clinical biomarkers. Multiple linear regression models were applied to quantify the associations and interactions while controlling for confounders, and a restricted cubic spline function estimated the corresponding dose-response curves of the relationships. Overall, KDM-biological age acceleration was associated with PM_2.5 component exposure over the preceding year in both males and females, with calcium [females: 0.795 (95% CI: 0.451, 1.138); males: 0.712 (95% CI: 0.389, 1.034)], arsenic [females: 0.770 (95% CI: 0.641, 0.899); males: 0.661 (95% CI: 0.532, 0.791)], and copper [females: 0.401 (95% CI: 0.158, 0.644); males: 0.379 (95% CI: 0.122, 0.636)] having greater estimates of the effect than total PM_2.5 mass. Additionally, we observed that the associations of specific PM_2.5 components with aging were lower in the higher sex hormone scenario. Maintaining high levels of sex hormones may be a crucial barrier against PM_2.5 component-related aging in the middle and older age groups.

Pollution characteristics and health risk assessment of PM2.5-bound arsenic: a 7-year observation in the urban area of Jinan, China

The aim of the study was to analyze the temporal trends, pollution sources, and carcinogenic health risks associated with PM_2.5-bound arsenic (As). A total of 588 PM_2.5 samples were collected in Jinan during January 2014-December 2020. The content and distribution characteristics were determined for As and Al in PM_2.5, and the pollution sources were identified based on enrichment factors (EFs). The health risk of inhalation exposure to As was estimated using the risk assessment methods recommended by the United States Environmental Protection Agency (US EPA). The annual average concentration of As in PM_2.5 was 4.5-17.5 ng m^-3, which was 0.8-2.9 times higher than the limit ruled by the European Union and China's Ambient Air Quality Standards (6 ng m^-3). From 2014 to 2020, the As concentration gradually decreased from 17.5 to 4.9 ng m^-3. After 2017, the concentration was close to the level required by the atmospheric quality standard (6 ng m^-3). The PM_2.5 and arsenic concentrations in the heating season were significantly higher than those in the non-heating season. The EF of As ranged from 144 to 607, which was higher than 10. The cancer risk of As in PM_2.5 decreased to the lowest values (heating season 1.0 × 10^-5 and non-heating season 7.1 × 10^-6, respectively) in 2019. As in Jinan mainly came from anthropogenic pollution. The level of As pollution has been significantly reduced in recent years, but there is still a high risk of carcinogenesis. Air pollution control strategies and guidelines need to be implemented in urban areas, especially during the heating season in winter and spring.

Risk assessment of heavy metals in suspended particulate matter in a typical urban river

Suspended particulate matter (SPM) is a major source of contamination in urban rivers as it serves as a carrier for pollutants, such as heavy metals. In this study, the Beiyun River, northern China, was used as a case study to determine the characteristics of SPM-associated heavy metal spatial distribution, to evaluate the potential ecological risks and identify heavy metal sources. The concentrations of seven heavy metals and other associated indicators (TC, TN, TP, and OM) were measured at 12 sites and analyzed by Pearson correlation (PC) and principal component analyses (PCA). The average concentrations of Cr, Ni, Cu, Zn, As, Cd, and Pb were 70.72, 27.88, 31.35, 115.70, 27.77, 0.23, and 29.62 mg/kg, respectively, with significant spatial differences occurring between some elements. Igeo values established the ranked order of heavy metal pollutant concentrations in SPM as As > Cd > Zn > Cu > Pb > Cr > Ni. [Formula: see text] analysis demonstrated that the ranked order of potential ecological risk from the seven metals was Cd > As > Cu > Pb > Ni > Cr > Zn. Potential ecological risk index (RI) results confirmed the high potential ecological risk in the study area. Among the measured heavy metals, Cd represented the highest pollution risk, as shown by its highest [Formula: see text] value. Correlation analysis (CA) showed that Zn had a strong correlation with Cu and Pb. Significant positive correlations were found between TC, TN, TP, and Cu. Three element pairs, Zn-Cd, Cr-Cu, and Cr-Ni, were also found to have strong correlations. Zn, Cu, and Ni were mainly introduced by human activities including urban industrial sewage discharge (such as metallurgy and electroplating industrial wastewater), agricultural drainage, and landfill wastewater, while Cr mainly originated from natural processes like mineral weathering and atmospheric precipitation. This information on the concentration, risk, and sources of SPM in Beiyun River provides an important reference for the reduction of heavy metal pollution in SPM in a typical river in the Haihe River Basin (China).

Health risk assessment of heavy metals in dust particles precipitated on the screen of computer monitors

Dust is an important factor to indoor pollution that contains suspended particles and heavy metals. Since today, use of computer has become an essential part of human life. Therefore, this study aimed to compare the amount of heavy metals deposited on CRTs and LCDs and their risk assessment. Ten dust samples for each type of monitor were collected from CRT and LCD screens in accordance with the standard OSHA ID-125 and ID-206, wet filter wipe method. Concentrations of Pb, Hg, Cd, Cr, and Cu were measured by inductively coupled plasma-optical emission spectrometer. Exposure and risk assessment of these elements were estimated using USEPA's exposure parameters. The average concentrations of heavy metals in the dust on CRTs (0.82 mg/kg) were higher than LCD screens (0.69 mg/kg). Cr with 62.824% and Hg with 0.849% had the highest and lowest average concentration in both types of monitors. The non-carcinogenic risk and carcinogenicity indexes of CRT monitors were 0.0009, and 3.94 × 10^-11 and for LCD monitors were 0.0008 and 2.94 × 10^-11. In both monitors, ingestion is the main route to exposure with heavy metals. The average concentration of heavy metals in CRT dust. HI values for studied metals in dust of CRTs and LCDs were less than safe limit of 1. Because RI < 10^-4, cancer risk of studied elements in dust can be ignored.

Arsenic and lead in the indoor residential settings of different socio-economic status; assessment of human health risk via dust exposure

In the present study, occurrence of arsenic (As) and lead (Pb) is reported in rural and urban household dust (floor and AC filter dust) of the Kingdom of Saudi Arabia (KSA). Several studies have found concerning concentrations of these toxic metals in indoor dust from different countries, but data from this region is missing. The association between studied toxic metals and different socioeconomic parameters was investigated. Furthermore, health risk associated with these toxic metals via dust exposure was evaluated for the Saudi population. Mean concentration of Pb was several times higher than As in both types of dust samples. AC filter dust was more contaminated with these metals than floor dust. Levels of Pb were up to 775 ppm in AC filter dust from urban areas, while 167 ppm in rural AC filter dust. Different socioeconomic parameters did not influence much on the presence of studied metals in both AC and floor dust. To estimate health risk from contaminated dust hazardous index (HI), hazardous quotient (HQ), and incremental lifetime cancer risk (ILCR) via dust ingestion, inhalation, and dermal contact was calculate using USEPA equations. The ILCR range for both toxic metals was within the tolerable range of reference values of USEPA (1 × 10^-5 to 5 × 10^-7). Nonetheless, HI was close to 1 for Pb via dust exposure for young urban children, which signifies the risk of non-carcinogenic health problems in studied area. Graphical abstract.

Temporal trend of arsenic in outdoor air PM2.5 in Wuhan, China, in 2015-2017 and the personal inhalation of PM-bound arsenic: implications for human exposure

Arsenic in fine air particulate matter (PM_2.5) has been identified as an important factor responsible for the morbidity of lung cancer, which has increased sharply in many regions of China. Some reports in China have shown that arsenic in the air exceeds the ambient air quality standard value, while long-term airborne arsenic concentrations in central China and human exposure via inhalation of PM-bound arsenic (inhalable airborne PM) have not been well characterized. In this study, 579 outdoor air PM_2.5 samples from Wuhan, a typical city in central China, were collected from 2015 to 2017, and arsenic was measured by inductively coupled plasma-mass spectrometry. Personal exposure to PM-bound arsenic via inhalation and urinary arsenic concentration were also measured. The concentrations of arsenic in PM_2.5 were in the range of 0.42-61.6 ng/m³ (mean 8.48 ng/m³). The average concentration of arsenic in 2015 (10.7 ng/m³) was higher than that in 2016 (6.81 ng/m³) and 2017 (8.18 ng/m³), exceeded the standard value. The arsenic concentrations in spring and winter were higher than those in summer and autumn. No significant differences (p > 0.05) were found among different sites. The daily intake of arsenic inhalation based on PM₁₀ samples collected by personal samplers (median, 10.8 ng/m³) was estimated. Urban residents inhaled higher levels of PM-bound arsenic than rural residents. Daily intake of arsenic via inhalation accounted for a negligible part (< 1%) of the total daily intake of arsenic (calculated based on excreted urinary arsenic); however, potential associations between the adverse effects (e.g., lung adenocarcinoma) and inhaled PM-bound arsenic require more attention, particularly for those who experience in long-term exposure. This study is the first report of a 3-year temporal trend of airborne PM_2.5-bound arsenic in central China.

Characterization, concentration and risk assessment of airborne particles using car engine air filter (case study: Tehran metropolis)

Atmospheric elements released into the atmosphere can enter the human body through inhalation, ingestion and dermal contact and are then deposited in the body. Trace elements have potential risks to human health. For this purpose, the particulate matter accumulated by car air filters (CAFs) was studied. The morphology and distribution of particle size were examined using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The concentration of elements in CAFs and CAF-estimated air for 30 elements in Tehran, Iran, was analyzed in winter and summer, from February to July 2017. Samples were determined by inductively coupled mass plasma spectrometry. The most abundantly detected elements in both CAFs and air in both seasons were Ca, Mg, Na and Fe. The shape of the particles was mostly irregular and spherical. Most of the particles were between 0.5 and 1.0 µm. The carcinogenic risks of inhalation exposure to Cr and Co in winter and summer were higher than the acceptable level (< 1 × 10^-4) for children and adults. The carcinogenic risks of As and Cr in both seasons were higher than 1 × 10^-4 for children and adults via dermal contact. Also, the carcinogenic risks of Cr in both seasons of ingestion exposure were higher than 1.00E-04 for children and adults. The integrated noncarcinogenic risks of all trace elements were higher than the safe level (= 1) for children and adults in both seasons.

Seasonal Characteristics of the Chemical Composition of Fine Particles in Residences of Nanjing, China

Indoor fine particulate matter (PM2.5) and its chemical composition is important for human exposure as people spend most of their time indoors. However, few studies have investigated the multiseasonal characteristics of indoor PM2.5 and its chemical composition in China. In this study, the chemical composition of PM2.5 samples in residences was analyzed over four seasons in Nanjing, China. Indoor water-soluble ions exhibited similar seasonal variations (winter > autumn > summer > spring) to those from outdoors (winter > autumn > spring > summer) except in summer. Whereas, indoor metallic elements exhibited a different seasonal pattern from that of outdoors. The highest concentrations of indoor metallic elements were observed in summer when the outdoor concentrations were low. The different seasonal variations of the chemical composition between indoor and outdoor PM2.5 indicated that people should consider both indoor and outdoor sources to reduce their exposure to air pollutants in different seasons. The carcinogenic risks for metallic elements were within the acceptable levels, while manganese (Mn) was found to have potential noncarcinogenic risk to humans. More attention should be paid to the pollution of Mn in the study area in the future. Moreover, the cumulative effect of noncarcinogenic PM2.5-bound elements should not be ignored.

Health risk assessment on human exposed to heavy metals in the ambient air PM10 in Ahvaz, southwest Iran

Heavy metals (HM) are one of the main components of urban air pollution. Today, megacities and industrial regions in southwest of Iran are frequently suffering from severe haze episodes, which essentially caused by PM₁₀-bound heavy metals. The purpose of this study was to evaluate the health risk assessment on human exposed to heavy metals (Cr, Ni, Pb, and Zn) in the ambient air PM₁₀ in Ahvaz, southwest Iran. In this study, we estimated healthy people from the following scenarios: (S3) residential site; (S2) high-traffic site; (S1) industrial site in Ahvaz metropolitan during autumn and winter. In the current study, high-volume air samplers equipped with quartz fiber filters were used to sampling and measurements of heavy metal concentration. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was utilized for detection of heavy metal concentration (ng m^-3). Also, an estimate of the amount of health risk assessment (hazard index) of Cr, Ni, Pb, and Zn of heavy metal exposure to participants was used. Result of this study showed that the residential and industrial areas had the lowest and the highest level of heavy metal. Based on the result of this study, average levels of heavy metal in industrial, high-traffic, and residential areas in autumn and winter were 31.48, 30.89, and 23.21 μg m^-3 and 42.60, 37.70, and 40.07 μg m^-3, respectively. Based on the result of this study, the highest and the lowest concentration of heavy metal had in the industrial and residential areas. Zn and Pb were the most abundant elements among the studied PM₁₀-bound heavy metals, followed by Cr and Ni. The carcinogenic risks of Cr, Pb, and the integral HQ of metals in PM₁₀ for children and adults via inhalation and dermal exposures exceeded 1 × 10^-4 in three areas. Also, based on the result of this study, the values of hazard index (HI) of HM exposure in different areas were significantly higher than standard. The health risks attributed to HM should be further investigated from the perspective of the public health in metropolitans. The result of this study showed increasing exposure concentrations to heavy metal in the studied scenarios have a significant potential for generating different health endpoints, while environmental health management in ambient air can cause disorders in citizenship and causing more spiritual and material costs.

Trace elements in PM2.5 in Shandong Province: Source identification and health risk assessment

The chemical compositions in PM_2.5 in metropolitan areas have obtained lots of attentions, of which concerns of airborne trace elements are relatively lacking. Here, PM_2.5 samples were collected simultaneously in one year at four urban sites (Zibo (ZB), Zaozhuang (ZZ), Qingdao (QD) and Jinan (JN (Shandong University)), and a rural site (JN (Miaopu)) in Shandong province. 25 elements (Al, Na, Cl, Mg, Si, S, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Sr, Cd, Ba and Pb) in PM_2.5 were measured by wavelength dispersive X-ray fluorescence spectrometer (WDXRF). Most trace elements (Al, Na, Cl, Mg, Si, Ca, Ti, Mn, Fe, Co, Ni, As, Se, Br, Cd, Ba and Pb) exhibited the highest levels at ZB and the lowest at QD. Meanwhile, they presented obvious seasonal variations with the highest concentrations in winter or spring and the lowest in summer. S and K were the most abundant elements in the area. In the non-crustal trace metal elements, Zn, Pb and Mn presented the highest concentrations. Positive matrix factorization (PMF) modeling revealed that secondary formation, coal combustion and industry emissions were the main sources in the region. The health risk assessments suggested that at the five sites Cd (diet) for adults, Pb and Co for children, and Mn (diet) for both adults and children (at ZB and SDU sites) had non-carcinogenic risks. As and Pb for adults and children existed carcinogenic risks, especially Pb for children. The sources of these elements with health risks were further explored. Notably, Cd, As and Pb should be paid special attention in the area due to their high concentrations in aerosol water exceeding the acceptable health risks, especially Pb.

Spatio-temporal distribution of metals in household dust from rural, semi-urban and urban environments in the Niger Delta, Nigeria

Concentrations of metals in household dust samples from rural, semi-urban and urban zones of the Niger Delta in Nigeria were measured during both 2009 and 2014 with the aim of providing information on changes in the concentrations, distribution patterns, sources and risks of metals in these zones. The concentrations of metals in the dust samples were quantified by using inductively coupled plasma atomic emission spectrophotometry (ICP-AES) after digestion with aqua regia. The measured concentrations (mg kg^-1) of metals in the three zones within the study periods were as follows: <LOQ-21.2; <LOQ-182; 7.90-265; <LOQ-117; <LOQ-471; 3.37-2310; 0.35-7.9; 4.25-365; 6.78-61,600; 219-37,700; and 1180-18,000 for Cd, Pb, Ba, Cr, Ni, Cu, Co, Mn, Zn, Fe and Al, respectively. The results from the two periods indicate significant changes in the concentrations, distribution patterns and risk factors which reflects a deterioration of the quality of the household environment over this time span. The hazard index (HI) values calculated for children were greater than 1 indicating significant non-cancer risks for these subjects in these areas. The HI values for adults were less than 1 and consequently do not pose a significant risk. The carcinogenic risk levels for exposure to metals for both adults and children in these zones were below the range specified as safe by the US EPA (×10^-6 and ×10^-4) thereby indicating a low cancer risk. The sources of metals in household dust from these zones include emissions from industries, traffic, artisanal workshops and releases from household furniture, metal-based fittings, metal roofing and pesticides.

Metals compositions of indoor PM2.5, health risk assessment, and birth outcomes in Lanzhou, China

The study aimed to investigate the metal compositions in indoor PM2.5 and the potential health risks they pose to residents of an urban area in China. A total of 41 and 54 households were surveyed in February and September 2013, respectively. The results showed that the indoor concentrations of metals varied depending on the types of cooking fuels used. All measured concentrations of metals were highest among households using coal for cooking. In the majority of households, non-carcinogenic risks were posed by the use of coal. The carcinogenic risks posed by chromium (VI) and arsenic were generally higher among households using coal for cooking than among those using gas or electricity. The multivariate linear regression model suggested a potential adverse effect from arsenic and cadmium on birth weight and gestational weeks. This study also found that cooking fuel was the most significant factor that contributed to the differences in concentrations of metals in indoor PM2.5 and highlighted the importance of using clean energy for cooking and heating.