The atmospheric deposition of major, minor and trace elements within and around three cement factories

Potential effects of heavy metal pollution from a cement factory near Saudi Arabia's largest green turtle rookery

Sand samples were collected from four beaches near a cement factory in Ras Baridi, north of Yanbu, which hosts the largest green turtle rookery in Saudi Arabia. Heavy metal concentrations (Cd, Pb, Fe, Cr, Ni, Se, Sb, As, and Cu) were measured at three different depths. For most elements, there were no significant differences in concentrations among depths; however, significant differences were found among the nesting beaches in Ras Baridi, which were likely influenced by the wind direction from the factory. Fe, Cr, Cu, and Ni had elevated contamination factor values, suggesting that the nesting beaches downwind and adjacent to the cement factory contained moderately contaminated sand. Given the possibility of heavy metals being absorbed through eggshells, there is a potential risk of heavy metal contamination in clutches laid in Ras Baridi. The rising threat to the local ecology in Saudi Arabia due to recent coastal developments for tourism projects highlights the importance of monitoring heavy metal concentrations over time.

Review of Particulate Matter and Elemental Composition of Aerosols at Selected Locations in Nigeria from 1985-2015

BACKGROUND

Over the past 30 years, various studies in Nigeria have monitored atmospheric particulate matter loads and elemental composition of ambient air around diverse receptor sites.

OBJECTIVES

A comparative discussion of the different sampling techniques, pre-treatment and analytical methods employed between 1985 and 2015.

METHODS

Air pollution indices from studies covered in this review were compared to relevant guideline standards such as the World Health Organization (WHO) 24-hr guideline and the United States Environmental Protection Agency (USEPA)'s National Ambient Air Quality Standard (NAAQS) daily permissible limits for fine particles of less than 2.5 micrometers in diameter (PM2.5) and coarse dust particles with a diameter of 10 micrometers (PM10) in ambient air. In addition, the sources of data for the average concentrations for PM2.5, PM10 and related metallic elements during 1985-2015 were assessed. Attempts were also made to compare varied particulate matter loads of atmospheric micro-environments in Nigeria with comparable micro-environments in selected cities around the world.

DISCUSSION

Results showed that PM2.5 concentration ranged from 5-248 μg/m3, while PM10 concentration ranged from 18-926 μg/m3, revealing that about 50% of the particulate matter loads in Nigeria exceeded both the WHO (25 μg/m3, 50 μg/m3) and NAAQS (35 μg/m3, 150 μg/m3) guideline limits for PM2.5 and PM10 respectively. PM2.5/PM10 ratios for the selected studies fall below the WHO guideline (0.5-0.8), suggesting that Nigerian aerosols are mainly made up of coarse, rather than fine particles. In addition, the order of the average highest concentrations of metallic elements for PM2.5 were magnesium (Mg) > strontium (Sr) > potassium (K) > zinc (Zn) > iron (Fe) > sodium (Na) > aluminium (Al) > chlorine (Cl) > lead (Pb) > silicon (Si), while those of PM10 were Sr > Zn > Fe > Mg > calcium (Ca) >Na > Pb > manganese (Mn) > K > Al.

CONCLUSIONS

Seasonal variation of particulate matter loads revealed higher concentrations during the dry season than during the rainy season. In addition, particulate matter loads in rural areas were generally lower than in urban areas. Wind-blown dust from the Sahara Desert is the major contributor to particulate matter loads in northern zones of the country, while sea spray and crustal matter are the highest contributors to particulate matter loads in southern zones.

Outdoor air particle-bound trace metals in four selected communities in Ibadan, Nigeria

Trace metal concentrations were determined in particulate matter (PM10) in ambient air of four purposively selected residential areas in Ibadan, Nigeria namely Bodija market (BM), Ojo Park (OP), Oluyole Estate (OE) and University of Ibadan (UI). PM10 was determined in the morning (7-10 a.m.) and afternoon (2-5 p.m.) for 12 weeks in the dry season months of January-March using a volumetric sampler following standard procedures and levels compared with WHO guideline limits. Glass-fibre filter papers exposed to the particulate matter were digested using appropriate acid mixtures, and the digest analysed for trace metals including Ni, Cr, Mn, Zn, and Pb using ICPMS method and levels compared with WHO limits. Data was analysed using ANOVA and Pearson correlation test at 5 % level of significance. The highest mean PM10 concentrations 502.3 ± 39.9 μg/m(3) were recorded in the afternoon period at BM, while the lowest concentration 220.6 ± 69.9 μg/m(3) was observed in the morning hours at UI. There was a significant difference between the PM10 levels across the various locations (p < 0.05), and all the levels were higher than WHO limit of 50 μg/m(3). The highest levels of Ni, Zn and Pb were recorded at BM, which also had the highest PM10 burden. The trend in Pb levels across the locations was BM > UI > OP > OE with the highest level 5.70 μg/m(3) in BM nearly fourfolds WHO limits of 1.5 μg/m(3). There was a significant correlation between PM10 and Ni (p < 0.05).Urban communities with increased human activities especially motor traffic recorded both higher levels of PM10 and toxic trace metals. There is need to carry out source apportionment to establish the origin of these trace metals in future studies.

Basin-scale contributions of Cr, Ni and Co from Ortegal Complex to the surrounding coastal environment (SW Europe)

The enrichment of Cr and Ni in the coastal zones is usually associated with anthropogenic sources such as the tanning, galvanization, ceramic, and cement industries. However, geological complexes of specific lithologic composition located near shorelines may act as natural sources of metals to the continental shelf. Cape Ortegal (SW Europe) is an ultramafic complex that has Cr, Ni and Co enriched in rocks due to the minerals chromite, chromospinel, gersdorfite and pentlandite. Thus, the hypothesis that this geological complex contributes to metal enrichment in Ortigueira and Barqueiro Rias and the adjacent continental shelf was tested. Chromium, Ni, and Co were determined in water and in suspended particulate matter of ria tributaries, rainfall, surface sediments, mussels, and algae. High contents of Cr (max. 1670mg·kg(-1)) and Ni (max. 1360 mg · kg(-1)) were found in the sediments surrounding Cape Ortegal and the Ortigueira Ria as a result of erosion of exposed cliffs. Dissolved Cr and Ni concentrations in fluvial waters were significantly higher in the rivers that crosses the Ortegal Complex, i.e. Lourido (0.47 μg Cr · L(-1); 9.4 μg Ni · L(-1)) and Landoi (0.37 μg Cr · L(-1); 4.3 μg Ni · L(-1)), in comparison with the nearby basin out of the complex influence (Sor River: <0.01 μg Cr · L(-1); 0.57 μg Ni · L(-1)). The annual fluvial contributions of Cr and Ni to the Ortigueira Ria were higher than fluxes into the Barqueiro Ria. Moreover, the increase in Cr and Ni in the rainfall in summer demonstrated the importance of the atmosphere pathway for introducing these elements into the aquatic environment. As a consequence, the contents of these metals in soft tissues and shell of mussels and algae from the Ortigueira Ria were higher than the organisms from Barqueiro Ria. Thus, geological complexes, such as the Cape Ortegal, located in an uncontaminated area, can increase the land-sea exchange of trace metals.

Characterization of spatial impact of particles emitted from a cement material production facility on outdoor particle deposition in the surrounding community

The objective of this study was to estimate the contribution of a facility that processes steel production slag into raw material for cement production to local outdoor particle deposition in Camden, NJ. A dry deposition sampler that can house four 37-mm quartz fiber filters was developed and used for the collection of atmospheric particle deposits. Two rounds of particle collection (3-4 weeks each) were conducted in 8-11 locations 200-800 m downwind of the facility. Background samples were concurrently collected in a remote area located -2 km upwind from the facility. In addition, duplicate surface wipe samples were collected side-by-side from each of the 13 locations within the same sampling area during the first deposition sampling period. One composite source material sample was also collected from a pile stored in the facility. Both the bulk of the source material and the < 38 microm fraction subsample were analyzed to obtain the elemental source profile. The particle deposition flux in the study area was higher (24-83 mg/m2 x day) than at the background sites (13-17 mg/m2day). The concentration of Ca, a major element in the cement source production material, was found to exponentially decrease with increasing downwind distance from the facility (P < 0.05). The ratio of Ca/Al, an indicator of Ca enrichment due to anthropogenic sources in a given sample, showed a similar trend. These observations suggest a significant contribution of the facility to the local particle deposition. The contribution of the facility to outdoor deposited particle mass was further estimated by three independent models using the measurements obtained from this study. The estimated contributions to particle deposition in the study area were 1.8-7.4% from the regression analysis of the Ca concentration in particle deposition samples against the distance from the facility, 0-11% from the U.S. Environmental Protection Agency (EPA) Chemical Mass Balance (CMB) source-receptor model, and 7.6-13% from the EPA Industrial Source Complex Short Term (ISCST3) dispersion model using the particle-size-adjusted permit-based emissions estimates.

Effects of cement flue dusts from a Nigerian cement plant on air, water and planktonic quality

Effects of cement flue dust from Ewekoro cement Kilns were monitored at some aquatic receptor locations. High levels of total suspended particulates (TSPs) and atmospheric deposition rates (ADRs) were recorded within the factory compared to ancillary locations outside the factory. The TSP and ADR levels which were location dependent were significantly higher (P < 0.05) during the dry periods than in the wet season. Irrespective of seasonal variations, the key elements in the emissions were Ca(2+) and Fe(2+). The concentrations of Zn(2+), Mn(2+) and Pb(+) which were trace elements were significantly higher (P < 0.05) in the deposited than in the airborne particulates. The planktonic flora and fauna of the river systems draining the area were poor with 16 phytoplanktonic and nine zooplanktonic species. Numerically, the phytoplanktons were dominated by diatoms (Bacillariophyta) with Synedra sp. being the most abundant species. The zooplanktonic fauna dominated by rotifers had Lecane curvicornis as a regular occurrence in all the three catchment rivers. The physicochemical parameters assayed were significantly higher (P < 0.05) in the factory effluent discharges than in water samples from each of the catchment rivers. Seasonal variations inclusive, HCO(-)(3), CO(2-)(3), Ca(2+) and Mg(2+) constituted the major ionic component of water samples analysed irrespective of location. Alaguntan River which receives effluents directly from the factory had significantly higher levels (P < 0.05) of the assayed ions than the other two rivers draining the cement factory catchment areas.

Heavy metal pollution in topsoils near a cement plant: the role of organic matter and distance to the source to predict total and hcl-extracted heavy metal concentrations

Heavy metal and trace element concentrations were examined in topsoils to evaluate a cement plant and an industrial waste incinerator as pollution sources. As, Ba, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, U, Yb and Zn were measured by Neutron Activation Analysis (NAA), and Co, Cu, Fe, Ni, Pb and Zn by a 0.5M-hydrochloric extraction technique using an Atomic Absorption Spectrophotometer (AAS). The Cr total concentration and HCl-extracted Co and Mn were possibly related to wind transportation from an industrial area in the north of Córdoba city (Argentina). Cu, Pb and Zn in partial HCl extraction were influenced by the cement plant and the industrial area in the north of Córdoba city. The mean total Ba concentration was above the residential and agricultural land use limits stated in national and international legislation and was related to the distance to the cement plant. The concentrations of HCl-extracted heavy metals could be predicted by the organic matter percentage and the distance to the cement plant (with R(2) values of 0.50-0.74). The Ca total concentration was seen to have little influence whereas the organic matter percentage strongly affected HCl-extracted heavy metals according to the correlation analysis and multiple regression models. According to soil quality guidelines for environmental health, the human and wildlife populations in Yocsina might be experiencing toxic Ba and Cr effects.

Heavy metals in urban soils of central Jordan: should we worry about their environmental risks?

Forty soil samples collected from central Jordan were analyzed by atomic absorption spectrophotometry for Pb, Cd, Zn, Cr, and Hg. The samples were also investigated for mineralogy using X-ray, electron, and optical microscopes. Sequential extraction procedures were used to predict the percentages of the Pb, Zn, Cd, and Cr present in each of the soil geochemical phases. The clay mineral assemblage encountered in the analyzed samples is composed of kaolinite, smectite, illite, and illite/smectite mixed-layer. The nonclay minerals of the sand-sized fraction are composed mainly of quartz and calcite as major minerals with pyroxene, biotite, and feldspars as minor minerals. The enrichment factors of the measured heavy metals Pb, Cd, Zn, Cr, and Hg in the clay fraction (<2 microm) of the collected samples are 3.1, 16.6, 1.5, 0.9, and 4.5, respectively. According to the index of geoaccumulation, the soils of the study area are considered to be moderately contaminated with respect to Cd, uncontaminated to moderately contaminated with respect to Pb, Hg, and Zn, and uncontaminated with respect to Cr. The measured metals correlated positively with the determined physicochemical factors such as pH, clay content, organic matter content, and carbonate content. The relatively high concentrations of Cd, Pb, and Hg in the soils of the study area are related to anthropogenic sources such as cement industry, fertilizers, and vehicle exhausts. It was found that Pb, Zn, and Cr are associated mainly with the residual phases and are relatively immobile. On the other hand Cd is enriched in the carbonate phase of the analyzed soil samples. It is possible to suggest the sequence of mobility for Pb, Zn, Cd, and Cr in the analyzed soil samples as the following: Cd>>Pb>Cr>Zn.