Distribution of toxic metals and relative toxicity of airborne PM2.5 in Puerto Rico

AbstractThe exposure to airborne particulate matter (PM) and its constituents is an important factor to be considered when evaluating their potential health risk. Transition metals found in PM are known to contribute significantly to the exacerbation of respiratory ailments. Exposure to these constituents results in the induction of oxidative stress in the bronchial epithelium, thus promoting the secretion of inflammatory mediators. Therefore, it is important to know the contributions of PM2.5 constituents to further investigate their relationship with toxic responses and associated health risks. PM2.5 samples from three rural (Humacao, Guayama, and Guayanilla) and two urban (more populated) sites (Bayamón and Ponce) from Puerto Rico were analyzed for various inorganic constituents. A total of 59 trace elements were analyzed, of which eight were considered with the greatest toxic potential. The highest annual average concentration of PM2.5 was reported at the urban site of Ponce (5.82 ± 1.40 μg m−3), while Bayamón’s average concentration was not as high (4.69 ± 1.30 μg m−3) compared to concentrations at the rural sites Humacao, Guayama, and Guayanilla (4.33 ± 1.20 μg m−3, 4.93 ± 1.50 μg m−3, and 4.88 ± 1.20 μg m−3 respectively. The concentration at the Ponce site exhibited the highest summer value (7.57 μg m−3) compared to that of all the rural sites (~ 6.40 μg m−3). The lowest summer PM2.5 values were obtained at the Humacao site with an average of 5.76 μg m−3. Average Cu and Zn concentrations were 3- and 2-fold higher at the urban sites (0.68 ng m−3 and 6.74 ng m−3 respectively) compared to the rural sites (0.17 ng m−3 and 4.11 ng m−3). Relative toxicity of inorganic PM extract indicates Bayamón (urban) and Guayama with similar low LC50 followed by Humacao, Guayanilla, and finally Ponce (urban) with the highest LC50. Of the eight potential toxic metals considered, only Fe was found to be higher at the rural sites. To our understanding, there are different sources of emission for these metals which potentially indicate main anthropogenic sources, together with the trade winds adding periodically volcanic and African Dust Storm particulates that affect Puerto Rico. These results are the first of their kind to be reported in Puerto Rico.

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TOXIC METALS CONTENT AND SAFE USE OF Seseli pallasii HERB

10.7562/se2016.6.01.01 ◽

2016 ◽

Vol 6 (2) ◽

Author(s):

Marija Ilić ◽

Vesna stankov Jovanovic ◽

Violeta Mitić ◽

Marija Dimitrijević ◽

Jelena Cvetković ◽

...

Keyword(s):

Heavy Metals ◽

Traditional Medicine ◽

Toxic Metals ◽

Inductively Coupled Plasma ◽

Animal Health ◽

Optical Emission ◽

Average Concentration ◽

Anthropogenic Sources ◽

Emission Spectrometry ◽

Aboveground Part

Heavy metals, whether from natural or anthropogenic sources have the ability to migrate between differ ent parts of environment and accumulate in flora and fauna, finally reaching humans through food chain. The possibility that plants might be contaminated by heavy metals should be taken into account, when they are intended for use in pharmaceutical and food industry, because increased concentration of some metals may have an adverse effect on human and animal health. Wild medicinal herb Seseli pallasii have been used in traditional medicine as well as a spice in nutrition, hence an assessment of the presence of toxic metals in it is essential in order to ensure its safe application. Vegetative parts of plant S. pallasii (root, leaf, flower and fruit) from Southeast Serbia were analyzed to assess the content of toxic metals (Cd, Cr, Ni and Pb, using inductively coupled plasma with optical emission spectrometry (ICP-OES). The results have shown that the average concentration of Cd in the aboveground part was almost twice as high 0.21 ppm than in the root 0.11 ppm, concentration of Cr in aerial part was of 0.43ppm, in the root 0.29 ppm, concentration of Ni in the aboveground was of 0.98ppm, while in the root it was of 0.68ppm. The average concentration of Pb in the aboveground part and the root was almost the same (2.31 and 2.15 ppm, respectively). These facts evidenced that the contents of toxic elements in the studied medicinal plant species are below the recommended limits, confirming that S. pallasii from the examined area can be safely used in traditional medicine and nutrition. Key words: Seseli pallasii, toxic metals, ICP, safety .

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Characteristics of atmospheric Total Gaseous Mercury (TGM) observed in urban Nanjing, China

Atmospheric Chemistry and Physics ◽

10.5194/acp-12-12103-2012 ◽

2012 ◽

Vol 12 (24) ◽

pp. 12103-12118 ◽

Cited By ~ 54

Author(s):

J. Zhu ◽

T. Wang ◽

R. Talbot ◽

H. Mao ◽

C. B. Hall ◽

...

Keyword(s):

Solar Radiation ◽

Seasonal Pattern ◽

Warm Season ◽

Elemental Mercury ◽

Average Concentration ◽

Anthropogenic Sources ◽

Urban Site ◽

Total Gaseous Mercury ◽

Air Masses ◽

Gaseous Mercury

Abstract. Long-term continuous measurements of total gaseous mercury (TGM = gaseous elemental mercury (GEM) + reactive gaseous mercury (RGM)) were conducted simultaneously along with meteorological variables and a suite of trace gases at an urban site in Nanjing, China from 18 January to 31 December 2011. Measurements were conducted using a high resolution mercury vapor analyzer (Tekran 2537B) with 5-min time resolution. The average concentration of TGM was 7.9 ± 7.0 ng m−3 with a range of 0.8–180 ng m−3 over the study period. TGM concentrations followed a typical lognormal pattern dominated by a range of 3–7 ng m−3, which was significantly higher than the continental background values (~1.5 ng m−3) in Northern Hemisphere. The mean seasonal TGM concentrations decreased in the following order: summer, spring, fall, and winter. This seasonal pattern was quite different from measurements at most other sites around the world. We attributed high monthly average concentrations to the re-volatilization of deposited mercury during the warm season due to high temperatures and greater solar radiation. Previous modeling studies suggested that Nanjing and the surrounding region have the largest Chinese natural emissions during the summer. Positive correlations between temperature, solar radiation, and TGM concentration combined with no correlation between CO and TGM in summer provide a strong indication that natural sources are important in Nanjing while most sharp peaks were caused by anthropogenic sources. TGM concentrations in Nanjing exhibited a noticeable diurnal pattern with a sharp increase after sunrise and peak of greater than 8 ng m−3 during 7–10 a.m. local time. Further, seasonally averaged diurnal cycles of TGM exhibited considerably different patterns with the largest variation in spring and insignificant fluctuations in winter. Using HYSPLIT backwards trajectories from six clusters, it was indicated that the highest TGM concentrations, 11.9 ng m−3, was derived from local air masses. The cleanest air masses, with an average TGM concentration of 4.7 and 5.9 ng m−3, were advected from the north via fast transport facilitated by sweeping synoptic flows.

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Geochemical Characterization and Heavy Metal Sources in PM10 in Arequipa, Peru

Atmosphere ◽

10.3390/atmos12050641 ◽

2021 ◽

Vol 12 (5) ◽

pp. 641

Author(s):

Jianghanyang Li ◽

Greg Michalski ◽

Elizabeth Joy Olson ◽

Lisa R. Welp ◽

Adriana E. Larrea Valdivia ◽

...

Keyword(s):

Trace Elements ◽

High Altitude ◽

Mineral Dust ◽

Anthropogenic Sources ◽

World Health ◽

Urban Site ◽

Emission Sources ◽

Industrial Site ◽

Rural Sites ◽

The City

Particulate matter smaller than 10 μm (PM10) is an important air pollutant that adversely affects human health by increasing the risk of respiratory and cardiovascular diseases. Recent studies reported multiple extreme PM10 levels at high altitude Peruvian cities, which resulted from a combination of high emissions and limited atmospheric circulation at high altitude. However, the emission sources of the PM10 still remain unclear. In this study, we collected PM10 samples from four sites (one industrial site, one urban site, and two rural sites) at the city of Arequipa, Peru, during the period of February 2018 to December 2018. To identify the origins of PM10 at each site and the spatial distribution of PM10 emission sources, we analyzed major and trace element concentrations of the PM10. Of the observed daily PM10 concentrations at Arequipa during our sampling period, 91% exceeded the World Health Organization (WHO) 24-h mean PM10 guideline value, suggesting the elevated PM10 strongly affected the air quality at Arequipa. The concentrations of major elements, Na, K, Mg, Ca, Fe, and Al, were high and showed little variation, suggesting that mineral dust was a major component of the PM10 at all the sites. Some trace elements, such as Mn and Mo, originated from the mineral dust, while other trace elements, including Pb, Sr, Cu, Ba, Ni, As and V, were from additional anthropogenic sources. The industrial activities at Rio Seco, the industrial site, contributed to significant Pb, Cu, and possibly Sr emissions. At two rural sites, Tingo Grande and Yarabamba, strong Cu emissions were observed, which were likely associated with mining activities. Ni, V, and As were attributed to fossil fuel combustion emissions, which were strongest at the Avenida Independencia urban site. Elevated Ba and Cu concentrations were also observed at the urban site, which were likely caused by heavy traffic in the city and vehicle brake wear emissions.

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Characteristics of atmospheric total gaseous mercury (TGM) observed in urban Nanjing, China

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-25037-2012 ◽

2012 ◽

Vol 12 (9) ◽

pp. 25037-25080 ◽

Cited By ~ 1

Author(s):

J. Zhu ◽

T. Wang ◽

R. Talbot ◽

H. Mao ◽

C. B. Hall ◽

...

Keyword(s):

Solar Radiation ◽

Seasonal Pattern ◽

Warm Season ◽

Elemental Mercury ◽

Average Concentration ◽

Anthropogenic Sources ◽

Urban Site ◽

Total Gaseous Mercury ◽

Air Masses ◽

Gaseous Mercury

Abstract. Long-term continuous measurements of total gaseous mercury (TGM = gaseous elemental mercury (GEM) + reactive gaseous mercury, RGM) were conducted simultaneously along with meteorological variables and a suite of trace gases at an urban site in Nanjing, China from 18 January to 31 December 2011. Measurements were conducted using a high resolution mercury vapor analyzer (Tekran 2537B) with 5-min time resolution. The average concentration of TGM was 7.9 ± 7.0 ng m−3 with a range of 0.8–180 ng m−3 over the study period. TGM concentrations followed a typical lognormal pattern dominated by a range of 3–7 ng m−3, which was significantly higher than the continental background values (~1.5 ng m−3) in Northern Hemisphere. The mean seasonal TGM concentrations decreased in the following order: summer, spring, fall, and winter. This seasonal pattern was quite different from measurements at most other sites around the world. We attributed high monthly average concentrations to the re-volatilization of deposited mercury during the warm season due to high temperatures and greater solar radiation. Previous Modeling studies suggested that Nanjing and the surrounding region have the largest Chinese natural emissions during the summer. Positive correlations between temperature, solar radiation, and TGM concentration combined with no correlation between CO and TGM in summer provide a strong indication that natural sources are important in Nanjing. While most sharp peaks were caused by anthropogenic sources. TGM concentrations in Nanjing exhibited a noticeable diurnal pattern with a sharp increase after sunrise and peak of greater than 8 m−3 during 7–10 a.m. LT. Further, seasonally averaged diurnal cycles of TGM exhibited considerably different patterns with the largest variation in spring and insignificant fluctuations in winter. Using HYSPLIT backwards trajectories from six clusters, it was indicated that the highest TGM concentrations, 11.9 m−3, was derived from lacal air masses. The cleanest air masses, with an average TGM concentration of 4.7 and 5.9 m−3, were advected from the north via fast transport facilitated by sweeping synoptic flows.

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Geochemical and Mineralogical Characteristics of Airborne Particulate Matter in Relation to Human Health Risk

Minerals ◽

10.3390/min10100866 ◽

2020 ◽

Vol 10 (10) ◽

pp. 866 ◽

Cited By ~ 1

Author(s):

Marzena Rachwał ◽

Małgorzata Wawer ◽

Mariola Jabłońska ◽

Wioletta Rogula-Kozłowska ◽

Patrycja Rogula-Kopiec

Keyword(s):

Magnetic Susceptibility ◽

Particulate Matter ◽

Human Health ◽

Magnetic Particles ◽

Rank Order ◽

Human Health Risk ◽

Airborne Particulate Matter ◽

Ambient Air ◽

Average Concentration ◽

Health Indices

The main objective of this research was the determination of the geochemical and mineralogical properties of particulate matter: TSP (total suspended particles) and, especially PM1 (particles with aerodynamic diameter not greater than 1 µm) suspended in the air of a selected urban area in southern Poland. Identification of the emission sources of metals and metalloids bound in TSP and PM1 as well as the assessment of potential risk of urban ambient air to human health using hazard indices was an additional aim of this investigation. The daily TSP and PM1 quartz fiber filters collected during heating season were subjected to mass magnetic susceptibility (χ) measurements, SEM (Scanning Electron Microscopy) observations and geochemical analyses. Obtained results revealed that the concentration of TSP and PM1 well correlated with their mass-specific magnetic susceptibility. The good relationship between the PM concentration and χ suggests that magnetic susceptibility measurements can be a good proxy of low-level atmospheric dust pollution. The rank order of potentially toxic elements (PTE) based on average concentration was Ba > Zn > Al > Fe > Pb > Mn > Ti > Cu > Cr > Ni >As > Cd > V > Tl, both for TSP and PM1. PM1/TSP ratios for PTE concentrations and χ were around or slightly above unity, which indicated that PM1 was the main carrier of PTE (with the exception of cadmium, copper and lead) and technogenic magnetic particles. The non-carcinogenic and carcinogenic risks were confirmed by very high values of human health indices.

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In situ measurements of speciated atmospheric mercury and the identification of source regions in the Mexico City Metropolitan Area

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-207-2009 ◽

2009 ◽

Vol 9 (1) ◽

pp. 207-220 ◽

Cited By ~ 63

Author(s):

A. P. Rutter ◽

D. C. Snyder ◽

E. A. Stone ◽

J. J. Schauer ◽

R. Gonzalez-Abraham ◽

...

Keyword(s):

Point Source ◽

Mexico City ◽

Metropolitan Area ◽

Atmospheric Mercury ◽

Point Sources ◽

Rural Site ◽

Urban Site ◽

Trajectory Data ◽

Source Regions ◽

Rural Sites

Abstract. In order to expand the currently limited understanding of atmospheric mercury source-receptor relationships in the Mexico City Metropolitan Area, real time measurements of atmospheric mercury were made at a downtown urban site, and a rural site on the outskirts of Mexico City, during March 2006. Numerous short-lived increases in particulate mercury (PHg) and reactive gaseous mercury (RGM) concentrations were observed at the urban site during the 17 day study, and less frequent increases in gaseous elemental mercury (GEM) concentrations were measured at both the urban and rural sites. The episodic increases observed were attributed to plume impacts from industrial point source emissions in and around Mexico City. Average concentrations and standard deviations measured during the study were as follows: i) urban site; PHg=187±300 pg m−3, RGM=62±64 pg m−3, GEM=7.2±4.8 ng m−3, and; ii) rural site; GEM=5.0±2.8 ng m−3. Several source regions of atmospheric mercury to the urban and rural sites were determined using Concentration Field Analysis, in which atmospheric mercury measurements were combined with back trajectory data to determine source regions. Only some source regions correlated to mercury emission sources listed in the Federal Pollutant Release and Transfer Register, leaving the rest unaccounted for. Contributions of anthropogenic mercury point sources in and around Mexico City to concentration averages measured at the urban site during the study were estimated to be: 93±3% of reactive mercury (PHg and RGM), and; 81±0.4% of GEM. Point source contributions to GEM measured at the rural site were 72±1%. GEM and reactive mercury (PHg+RGM) were not found to correlate with biomass burning at either of the measurement sites.

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Nitrous Oxide: Trends and Global Mass Balance Over the Last 3000 Years

Annals of Glaciology ◽

10.1017/s0260305500004201 ◽

1988 ◽

Vol 10 ◽

pp. 73-79 ◽

Cited By ~ 64

Author(s):

M.A.K. Khalil ◽

R.A. Rasmussen

Keyword(s):

Nitrous Oxide ◽

Fossil Fuels ◽

Ice Cores ◽

Average Concentration ◽

Rate Of Change ◽

Nitrogen Fertilizers ◽

Anthropogenic Sources ◽

Polar Regions ◽

Atmospheric Concentration ◽

Slow Increase

We analyzed ice cores from both northern and southern polar regions to determine the concentrations of nitrous oxide in the pre-industrial and ancient atmospheres from about 150 years to 3000 yearsB.P.We found that the pre-industrial concentration of nitrous oxide remained constant over the period we studied and that the average atmospheric concentration was 285 ± 1 ppb volume (90% confidence limits), representing about 2100 Tg (2100 × 1012g) of N20 in the atmosphere, whereas the average concentration in 1984 was about 307 ppb volume or 2260 Tg. This is a change of 22 ppb volume (160 Tg), or about 8%, between pre-industrial and present times. Now the rate of change is between 0.7 and 0.9 ppb volume/year or 5 and 6.5 Tg/year, which is a slow increase of about 0.3% per year. The changes observed are probably caused by increasing use of fossil fuels, particularly coal and oil, and perhaps to a lesser extent by the use of nitrogen fertilizers in recent years. The atmospheric lifetime of N2O is probably between 100 and 150 years. The pre-industrial concentrations, present levels, and a lifetime of 100 years are consistent with natural sources, mostly soils and oceans, of about 22 Tg/year and the present anthropogenic sources of about 8.7 Tg/year. In the next 50 years we expect nitrous oxide levels to reach 360–390 ppb volume, or about 16–25% more than present.

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Particle size, morphology and characterization of indoor and outdoor airborne particulate matter for toxic metals in Karachi

International Journal of Environmental Science and Technology ◽

10.1007/s13762-020-02771-4 ◽

2020 ◽

Vol 17 (9) ◽

pp. 3969-3982 ◽

Cited By ~ 1

Author(s):

N. Ali ◽

I. Adil ◽

A. Magsi ◽

E. Asif

Keyword(s):

Particle Size ◽

Particulate Matter ◽

Toxic Metals ◽

Airborne Particulate Matter ◽

Airborne Particulate ◽

Indoor And Outdoor

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Atmospheric wet and litterfall mercury deposition in typical rural and urban areas in China

10.5194/acp-2016-505 ◽

2016 ◽

Author(s):

Xuewu Fu ◽

Yang Xu ◽

Xiaofang Lang ◽

Jun Zhu ◽

Hui Zhang ◽

...

Keyword(s):

Urban Areas ◽

Wet Deposition ◽

Arid Zone ◽

Atmospheric Mercury ◽

Urban Site ◽

Cloud Base ◽

Subtropical Zone ◽

Deposition Fluxes ◽

Precipitation Depth ◽

Rural Sites

Abstract. Mercury (Hg) concentrations and deposition fluxes in precipitation and litterfall were measured at multiple sites (six rural sites and an urban site) across a broad geographic area in China. The annual deposition fluxes of Hg in precipitation at rural sites and an urban site were 2.0 to 7.2 µg m−2 yr−1 and 12.6 ± 6.5 µg m−2 yr−1, respectively. Wet deposition fluxes of Hg at rural sites showed a clear regional difference with elevated deposition fluxes in the subtropical zone, followed by the temporal zone and arid/semi-arid zone. Precipitation depth is the primary influencing factor causing the variation of wet deposition. Hg fluxes through litterfall ranged from 22.8 to 62.8 µg m−2 yr−1, higher than the wet deposition by a factor of 3.9 to 8.7 fluxes and representing approximately 75 % of the total Hg deposition at the forest sites in China. This suggests that uptake of atmospheric Hg by foliage is the dominant pathway to remove atmospheric mercury in forest ecosystems in China. Wet deposition fluxes of Hg at rural sites of China were generally lower compared to those in North America and Europe, possibly due to a combination of lower precipitation depth, lower GOM concentrations in the troposphere and the generally lower cloud base heights at most sites that washout a smaller amount of GOM and PBM during precipitation events.

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