Assessment of land use effect, mapping of human health risks and chemometric analysis of potential toxic elements in topsoils of Aran-o-Bidgol, Iran.

This study examines topsoil contamination in Aran-o-Bidgol urban region of central Iran, with a focus on potentially toxic elements (PTEs). A total of 135 topsoil samples in different land types were characterized, ranging from areas with agricultural farms, desert, industrial and residential activity, and brick kilns. The average concentrations of Cd, Pb, Cu, Ni, Cr, Co, Fe, Zn, and Mn were 0.72, 11.41, 14.82, 29.87, 51.13, 106.69, 8741.87, 48.59, and 346.42 mg kg-1, respectively, which all exceed the local background levels. The results reveal that land use significantly affected PTE concentrations. Cr, Co, Mn, and Fe concentrations in soils of residential and brick kiln areas were especially high. In contrast, concentrations of Cu, Ni, and Zn were higher in agricultural and residential areas. Risk assessment analysis showed that the sum of toxic units for PTEs for brick kilns (1.72), residential (1.82), and agricultural (1.79) areas exceeded those of other land types and that Ni and Cr contributed the most to the high toxic risk index values. Both carcinogenic and non-carcinogenic risk indices of PTEs in soils were within an acceptable limit, except for the cancer risk of Ni (3.52E-04) and Cr (3.00E-04) among children. The spatial hazard index and carcinogenic health risk of PTEs showed that samples from the southwestern parts of the study area might pose significant health problems to adults and children. This study demonstrates how combining different techniques can help spatially characterize PTE accumulation and protect populations at risk.

Stress induced by heavy metals on breeding of magpie (Pica pica) from central Iran.

The aim of this study was to address the impacts of some heavy metals (Cd, Pb, Zn, Ni and Cu) contamination on laying behavior, egg quality and breeding performance of Pica pica in north of Isfahan Province, Iran. During the breeding season of 2013, magpie's egg content and eggshell as well as nestling excrements and feathers were collected and total concentrations of heavy metals were measured by ICP-OES. Except for Zn in nestling feathers, the significantly higher concentrations of heavy metals were observed in nestling excrements than other samples. Also, comparison of heavy metals concentrations in egg content and eggshell showed that egg content had significantly higher concentrations of Zn and Pb, instead eggshell had significantly higher amount of Cu and Cd. Except for Cu, all heavy metals concentrations in eggshell had a negative relationship with morphological characters; and also concentration of Cu in egg content showed a significantly negative correlation with egg weight and volume. The most of heavy metals in nestling feathers and excrements had strongly positive correlations with each other. Also all heavy metals levels in eggshell and egg content had significantly positive correlations (except for Cu). Unhatched eggs had significantly lower weight but also greater levels of Zn, Cd, and Pb, than randomly collected eggs. No significant differences were observed for morphometric measurements of eggs between different sites, however, a decreased gradient was observed in egg volume toward the brick kiln site. Samples collected in brick kiln site accumulated higher concentrations of heavy metals than other sites. Although numbers of clutch size in brick kiln site were significantly higher than other sites, however, other breeding variable were lower than other sites. It can be suggested that ecosystem contamination may be caused to decrease the reproduction rate of Pica pica in brick kiln, probably by laying more poor quality eggs per clutch and nestling mortality.

Spatial Eco-Risk Assessment of Heavy Metals in the Surface Soils of Industrial City of Aran-o-Bidgol, Iran.

Heavy metals usually accumulate and migrate in soil environment due to human activities and this in return poses potential ecological and health risks. A total of 135 surface soil samples were collected from Aran-o-Bidgol City, Iran and were analyzed for their Cd, Pb, Ni and Cu concentrations to determine these elements' spatial distribution and potential ecological risks. To this end, interpolation mapping was conducted using Ordinary Kriging. The mean concentrations of Cd, Pb, Ni and Cu in the samples were 0.72, 11.41, 29.87 and 14.82 mg kg(-1), respectively, which were all higher than their background values. The spatial variation in the concentration of heavy metals could be attributable to point sources and vehicle emissions. Considering the severity of the potential ecological risks of metals, the descending order of contaminants' concentrations was Cd > Cu > Ni > Pb. The Potential Ecological Risk Index (RI) suggested that approximately 40 % and 59 % of the samples posed high and significantly high potential ecological risks, respectively. Moreover, ecological risk decreased progressively going from southwest to northeast over the under-study area. Considering the background values and RI, this area presented a relatively high level of contamination.

Concentrations of Metals in Feathers of Magpie (Pica pica) from Aran-O-Bidgol City in Central Iran.

The present study aims to measure Zn, Cu, Pb and Cd concentrations in feathers of Magpies in urban areas to investigate the possibility of using Magpies to monitor metal contamination in urban areas. A total of 15 bird samples were collected in October 2013 from Aran-O-Bidgol City, in Central Iran and the concentration of metals were measured using a PerkinElmer ICP-OES. The average concentrations of Zn, Cu, Pb and Cd in the feathers were 167.16, 26.74, 9.29 and 1.583 µg/g dw, respectively. There were no significant differences in metal concentrations between various genders, ages and sites. However, the highest and lowest concentrations of non-essential elements were observed in the adult males and adult females, respectively. Significant correlations were observed between the concentrations of Cu and Zn as well as Pb and Cd. Moreover, wing length had the highest correlation with metals concentrations.

Comparative study of heavy metals concentration in topsoil of urban green space and agricultural land uses.

The main objective of this study was to determine the concentration of cadmium, chromium, copper, nickel, lead, and zinc in surface soils of two land uses including agricultural and urban green space in Semnan Province, Iran. For this purpose, the soil samples of 27 urban green space and 47 agricultural fields were collected and analyzed. The correlation coefficients, analysis of variance, principal component analysis, cluster analysis, and geoaccumulation index were utilized to compare the mean values in the two land uses and pinpoint the possible sources of contamination in the study area. The average contents of Cd, Cu, Cr, Ni, Pb, and Zn in green space soils were 0.1, 24.9, 78.7, 28.2, 22.1, and 82.1 mg/kg, respectively, while the mean concentrations of Cd, Cu, Cr, Ni, Pb, and Zn in agricultural soils were 0.3, 24.3, 83.7, 33.3, 18.1, and 80.4 mg/kg, respectively. The mean concentrations of lead, copper, and zinc were higher in urban green space in comparison with those of agricultural fields, while it was vice versa for chromium, cadmium, and nickel. In general, significant, but weak, correlations were observed between Zn with Pb (r = 0.53) and Cu (r = 0.61) and Ni with Cr (r = 0.55) and Cu(r = 0.51). The main sources of contamination turned out to be both natural and anthropogenic as the results of correlation coefficients, principal component analysis, and cluster analysis showed. That is to say, chromium and nickel had emanated from natural while the sources of cadmium, lead, and zinc could be attributed to anthropogenic activities. For the case of copper, both natural and anthropogenic activities were influential; however, the role of human activities was more effective. The results of contamination assessment showed that heavy metal contamination in agricultural land use was higher than green space indicating the role of human activities in this respect.

The Extent and Prediction of Heavy Metal Pollution in Soils of Shahrood and Damghan, Iran.

The levels of 12 heavy metals (Ag, Ba, Be, Cd, Co, Cr, Cu, Ni, Pb, Tl, V, Zn) were considered in 229 soil samples in Semnan Province, Iran. To discriminate between natural and anthropogenic inputs of heavy metals, factor analysis was used. Seven factors accounting for 90.5 % of the total variance were extracted. The mining and agricultural activities along with geogenic sources have been attributed as the main causes of the levels of heavy metals in the study area. The partial least squares regression was utilized to predict the level of soil pollution index (SPI) considering the concentrations of 12 heavy metals. The eigenvectors from the first three PLS represented more than 98 % of the overall variance. The correlation coefficient between the observed and predicted SPI was 0.99 indicating the high efficiency of this method. The resultant coefficient of determination for three PLS components was 0.984 confirming the predictive ability of this method.

Levels and variability of metals in soils of the province of Golestan (Iran).

Studying the concentration distribution of metals is necessary for soil pollution monitoring and maintaining environmental quality. To date, very little large-scale research has been performed to investigate metal contamination in developing countries. In this study, the content and spatial distributions of five metals (cadmium [Cd], copper [Cu], nickel [Ni], lead [Pb], and zinc [Zn]) were quantified based on 346 topsoil samples from 12 districts in the province of Golestan (northeast [NE] Iran). The concentration levels (mg/kg) of Cd, Cu, Pb, Ni and Zn varied from 0.02 to 0.36, 9.3 to 93.7, 6.8 to 44, 9.5 to 85.35, and 25 to 417.4, respectively. The average concentrations (mg/kg) obtained were as follows: Cd 0.12 ± 0.07, Cu 23.9 ± 9.07, Ni 34.88 ± 11.59, Pb 15.42 ± 5.81 and Zn 82.08 ± 30.87. Significant differences in the distribution of trace elements among districts were detected. The AzadShahr and BandarGaz districts displayed the highest metal concentrations. Greater metal values were obtained in the central, south, west, and NE areas, although Zn concentration was also high to the north of the province. Values of contamination factor and contamination degree indicated that the metal pollution level was on the order of Zn > Cd > Pb > Cu > Ni and that all of the metals belonged to a low or moderate pollution category. Ni and Cu levels derived from natural sources, whereas Cd, Pb, and Zn derived from anthropogenic activities with greater mean concentrations than reference concentrations.

Occurrence and abundance of macro, meso and microplastics along the coasts of the Persian Gulf (case study: Bushehr Province coast).

One of the most critical emerging pollutants in aquatic environments is plastic waste. During this study, the presence and abundance of macro, meso, and microplastics at 17 stations on the coast of Bushehr province were investigated. The average abundances of macro-plastics and meso-plastics in coastal sediment were 41.0 and 121.8 items/m2, respectively. The mean abundance of microplastics at depths of 0-5 cm, 5-15 cm, 0-15 cm and the mean of two depth abundance were 226.2 ± 76.7 and 47.1 ± 16.1, 273.4 ± 78.8, and 136.7 ± 39.4 particles/kgd.w., respectively. Fibers with 55 %, black microplastics with 40 %, and microplastic size of <500 µm with 48 % had the highest abundance, respectively. According to the FTIR spectra, polyethylene, polystyrene, polyethylene terephthalate, and nylon were the most common types of polymers in plastics. Although plastics were observed at all stations, a comparison of our results, with other studies around the world shows that the region is moderately contaminated with plastics.

The effect of irrigation with treated and untreated wastewater on the yield and chemical composition of essential oil of Mentha spicata L. and Rosmarinus officinalis L.

Today, the lack of quality water supply has led to the tendency to use unconventional water to irrigate agricultural products. Considering the importance and application of essential oils of mint plants in various pharmaceutical, food, and health industries and also considering the approach of using unconventional waters in the cultivation of medicinal plants, the present study aimed to investigate and compare the chemical composition of essential oils of two species of Mentha spicata L. and Rosmarinus officinalis L. which was designed and implemented for the first time under the influence of different treatments of municipal and industrial wastewater. For this purpose, first R. officinalis cuttings and roots of M. spicata were prepared and after preparing and leveling the ground, in the spring of 2020, it was transferred to the planting site and planted in the form of creek and ridges. The treatments studied in this study included well water (WW), treated municipal wastewater (TMW), untreated municipal wastewater (UMW), treated industrial wastewater (TIW), and untreated industrial wastewater (UIW) in a randomized complete block design with four repeat runs. After watering the plants continuously for 3 months, the plant branches were collected and transferred to the laboratory for drying. After extracting the essential oil by water distillation (Clevenger) method, the analysis and identification of the compounds were performed by a chromatograph coupled with a mass spectrometer (GC/MS). The results showed that the highest and lowest yields of M. spicata belonged to the samples treated with UMW and WW, respectively. Also, R. officinalis essential oil irrigated with UMW and UIW had the highest and lowest yields, respectively. The number of essential oil compounds in of M. spicata was between 5 and 19 and in R. officinalis between 14 and 23 under different treatments. The results of the analysis of essential oil compounds showed that D-carvone (57.77-57.44%) and D-limonene (8.70-26.65%) for M. spicata and α-pinene (26.12-34.85%), 1,8-cineole (18.95-23.70%), and camphene (9.93-12.80%) for R. officinalis were predominant compounds in all studied treatments. The results show that UMW is a suitable and efficient treatment to have the best quantity of M. spicata essential oil and the best quality and quantity of R. officinalis essential oil.

Occurrence, abundance and characteristics of microplastics in some commercial fish of northern coasts of the Persian Gulf.

This study assessed the abundance of microplastics (MPs) in muscle, liver, gill, and gastrointestinal tissues of 14 fish species from the Persian Gulf. The quality control showed no significant difference in MPs abundance between blank samples and muscle and liver tissues. The mean abundance of MPs accumulated in gill and gut was 2.85 ± 1.57 and 2.46 ± 1.46 pa/individual, respectively. The maximum mean abundance of MPs was observed in the gill (5.71 pa/ind) of the fish Thunnus tonggol and gut tissue (5.67 pa/ind) of the fish Sphyraena putnamiae. Fiber, black color and size of 23-75 µm were the predominant form of MPs. There was a significant positive correlation between the total fish length and the abundance of MPs. MPs were more abundant in pelagic fish (5.79 ± 5.98) than demersal fish species (3.89 ± 3.53). The level of fish contamination with MPs was low to moderate in comparison to the ranges reported in the literature.

A web-based GIS system for wildlife species: a case study from Khouzestan Province, Iran.

Recent efforts to aggregate, process, and use biodiversity information have appended novel opportunities and challenges for the field, and a rapid increase in studies that integrate and analyze data in the biological-ecological realm. We developed a web-based GIS system for the wildlife of Khouzestan Province that provides potential distribution maps and other spatial and nonspatial data on the wildlife of Khouzestan Province and its protected areas. We used MaxEnt and a fuzzy inference system to model distributions of species. Our application was structured using a client/server architecture, and the database design and construction was carried out using PostgreSQL/PostGIS, and GeoServer to serve maps. The mapping interface was developed using OpenLayers; ASP.NET was selected for designing the user interface. We used qualitative-quantitative methods to develop, design, refine, and finalize our system particularly as regards usability. The design approach resulted in a user-friendly interface that allows both specialists and non-specialists to quickly and efficiently run models to estimate potential distributions of species. Our application highlights what can be accomplished with a biodiversity-oriented web application.

Tissue distribution and oral exposure risk assessment of heavy metals in an urban bird: magpie from Central Iran.

Direct ingestion of soil and/or soil attached to the food items is a potential rout for wildlife exposure to contaminants. In this study, bioaccumulation of five heavy metals (HMs) in internal tissues of an urban bird (Pica pica) collected from Aran-O-Bidgol City, Central Iran and their related soil were investigated. A total of 15 magpie specimens were collected in autumn 2013 and then their internal tissues were digested using a mixture of HNO3 and H2O2, and finally, concentrations of HMs were detected by ICP-OES. In addition, in order to show level of HM exposure risk to magpie, an exposure risk assessment was modeled. Results indicated that HMs were accumulated as follows: liver > kidney > muscle. Zn and Cu were significantly higher in magpie's tissues collected from agricultural site; on the other hand, Pb and Cd were significantly higher in industrial site (p < 0.05). Level of Cd in male's livers (2.11 µg/g dw) was significantly higher than in females (1.85 µg/g dw) (p < 0.05). Levels of Cd, Pb, and Ni in liver, muscle, and kidney, respectively, were significantly higher in adults than in subadults (p < 0.05). Soil exposure doses of all HMs were lower than tolerable daily intake (Zn 4.35, Cu 1.34, Ni 5.65, Pb 0.35, and Cd 0.53). The calculated hazard quotations (HQs) for HMs were as follows: Pb > Zn > Cu > Ni > Cd and for all HMs were at no risk level (HQ < 1). The amounts of hazard index for three sites were as follows: urban (1.032) > agriculture (0.943) ≥ industry (0.941) and only for urban area was at low risk (1 < HQ < 2). It seemed that birds living in a safe environment and/or HM contaminations in soil separately had no negative effects on magpies. We can also suggest that low levels of HMs in magpie's tissues can be due to low levels of HMs in soil.

Evaluation of some factors influencing on variability in bioaccumulation of heavy metals in rodents species: Rombomys opimus and Rattus norvegicus from central Iran.

In the present study, the effects of sex, age, nutritional status, and habitat use on hair and internal tissue concentrations of some trace metals (Zn, Cu, Ni, Pb and Cd) in brown rat (Rattus norvegicus) and great gerbil (Rhombomys opimus) from Aran-O-Bidgol City in Central Iran were investigated. Five sampling stations in different land-uses were selected for the study. Concentrations of Cd and Pb in liver and whole body concentration as well as concentration of Zn in hair of male rats were significantly higher than females. A significantly higher concentration was only observed for Pb in kidney of male gerbils than females. In numerous cases, age had significantly negative correlations with concentration of metals in different tissues of both species, and was only significantly (and positively) correlated with the concentration of Cd in kidney and Zn in liver of gerbils. This finding may indicate that the early neonatal age is a critical period for metals accumulation. The relationships between nutritional status and metal concentrations for both species were negative, which can be ascribed to the weight-specific metabolic rate that cause to a relatively low uptake of metals per unit of body weight. No significant differences were observed for soil metals concentrations in different sites. So, this suggests that the influence of life history, microhabitat use and foraging behavior did significantly influence on inter and intra specific variation of metals concentration in small mammals. Our observations suggest that hair cannot be used alone for monitoring exposure of metals.

Comparison of interpolation methods for the estimation of groundwater contamination in Andimeshk-Shush Plain, Southwest of Iran.

Selection of appropriate interpolation methods for the conversion of discrete samples into continuous maps is a controversial issue in the environmental researches. The main objective of this study was to analyze the suitability of three interpolation methods for the discrimination of groundwater with respect to the water quality index (WQI). The groundwater quality data consisted of 17 variables associated with 65 wells located in Andimeshk-Shush Plain. Three spatial interpolation methods including ordinary kriging (OK), empirical Bayesian kriging (EBK), and inverse distance weighting (IDW) were utilized for modeling the groundwater contamination. In addition, different cross-validation indicators were applied to assess the performance of different interpolation methods. The results showed that the performance differed slightly among different methods, although the best performed interpolation method in this study was the empirical Bayesian kriging. Among the interpolation methods, IDW with weighting power of 4 estimated the most contaminated area, while OK estimated the lowest contaminated area. The weighting power of IDW had a significant influence on the estimation, meaning that the estimated contaminated area was increased when a greater weighting power was selected. The subtraction results indicated that there are slightly spatial differences among the contamination assessment results. Results of both standard deviation (SD) and coefficient of variation (CV) also showed that uncertainty was highest in the southern part of the study area, where the distribution of wells were more intensive than that of the northern part.