Investigation of metal concentrations in roadside soils and plants in urban areas of Amritsar, Punjab, India, under different traffic densities.

Vehicular emissions containing traces of different heavy metals are known to cause significant contamination of roadside soils and plants. The present study was conducted to investigate the heavy metal concentrations in roadside soil and plant samples (Alstonia scholaris, Nerium oleander, Tabernaemontana divaricata, and Thevetia peruviana) collected from urban areas of Amritsar city of Punjab, India, under different traffic densities. The soil and plant samples were collected in pre- and post-monsoon seasons from seven roadside sites under varying levels of traffic density and analyzed for four heavy metals (Cd, Cu, Pb, and Zn). In addition to that, total protein and carotenoid contents in plant samples were also determined. pH and electrical conductivity analysis of roadside soil samples revealed slight to strongly alkaline and non-saline nature of soil. Significant reduction in contents of total proteins and carotenoids was observed in plants collected from sites with moderate to high traffic density. The trend of heavy metal contents in plants and their corresponding soil samples was observed to be Zn > Cu > Pb > Cd for both the seasons. Index of geo-accumulation indicated moderate contamination of soil with metals analyzed, while bio-accumulation factor (BAF) showed both absorption and accumulation of metals in plants under study. The study revealed significant contamination of roadside soil and plants of Amritsar city which was linked to vehicular emissions posing potential risk to human health.

Distribution and accumulation ability of heavy metals in bivalve shells and associated sediment from Red Sea coast, Egypt.

Concentrations of Fe, Mn, Cu, Zn, Pb, Ni, Cd, and Co in molluscan shells and associated surface sediments from four sites on the Gulf of Aqaba and Red Sea coasts, Egypt, were measured by using atomic absorption spectrophotometer. The results revealed an apparent difference in the ability of each species regarding accumulating heavy metals in its shell. These results showed that Tridacna squamosa has the highest accumulation ability for Pb, Ni, and Zn, and Chama pacifica has the highest accumulation capability for Co and Cd, whereas Periglypta reticulata has the highest accumulation ability for Cu. The results also showed that there is a positive correlation between the concentration of Cu, Zn, Pb, and Ni and the size of shell. Simultaneously, there is a negative correlation with Fe, Mn, Co, and Cd. The results of bio-accumulation of molluscan species were consistent with the enrichment factors for sediments, where the Hurghada site was extremely enriched with Pb and very enriched with Cu, Zn, and Ni. Moreover, the Quseir site was extremely enriched with Cd and very enriched with Pb. The Um al-Sid site was severe enriched with Cd and Pb. Meanwhile, the Ras Mohamed site was severe enriched with Pb and nearly unpolluted with other metals. Heavy metals can enter the studied ecosystem by terrigenous and anthropogenic sources as a weathering process of the nearby beaches and mountains, ship maintenance, industrial activities, wastewater, and traffic exhaust.

Spatial Distribution and Bio-accumulation of Cadmium and Lead in Soil, Rice and Vegetables in Typical Pollution Areas, China.

The adverse effects of Cd and Pb on human health have been widely reported. While, there were several typical pollution areas in China which has not been investigated comprehensively and deeply. In this study, 475 soil and 472 plant samples from these pollution areas were analyzed for Cd and Pb with ICP-MS. Here, the pollution levels of different areas were analyzed and compared; the spatial distributions in soil, rice and cabbage samples were illustrated in map; and the relationships of Cd and Pb in soil and rice, soil and cabbage were also discussed. The results showed that Cd pollution still existed in some south, central-south and south-east zones except other three zones located in suburb of Tianjin, north-east and north China which might be explained by the higher background values, soil acidity, Karst landscape and metallurgy industry. Comparatively, the Pb concentrations showed lower over-standard rate. Moreover, the spatial distribution of Cd and Pb in rice and cabbage showed similar trends with those of soil samples. Particularly, the average Cd and Pb concentrations in lettuces were much higher than those in other plants. Cd and Pb concentrations in rice and cabbage showed low linear dependence with the concentrations in soil. The results in this study added basic environmental data and would be helpful to future soil remediation of these areas.

Aluminium accumulation in excess and related anti-oxidation responses in C4 weed (Amaranthus viridis L.).

C4 species, Amaranthus viridis L. exhibited a significant bioaccumulation of aluminium (Al) through the duration of 3- and 5-days exposure. As compared to control, Amaranthus appeared as excess-accumulator with maximum 5.85-fold bioaccumulation of Al in root. Cellular responses to Al tolerance initially scored tissue specific distribution of metal through cortical layers revealed by electron microscopy. The affected cells changed an oxidative status as read by histochemical stains, particularly, for hydrogen peroxide. Osmotic stress and its stability were scored by maximum proline and free amino acids accumulation with 1.53 and 1.59-fold increase over control. The accumulation of phenolics and flavonoids were over expressed in the ranges of 2.48-2.50-fold and 2.00-1.5-fold at 3- and 5-days respectively against control. Anti-oxidation to detoxify Al stress was facilitated by variants of peroxidases. For exclusion mechanism of metal, esterase activity significantly over expressed with maximum value of 1.80-fold at 5-days. The polymorphism of esterase exhibited few significant over produced bands, varied in numbers as detected by densitometric scanning. Moreover, plant extract was satisfactorily potential under in vitro anti-oxidation systems through assay of 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), ferric chelation activity etc. Therefore, weeds like Amaranthus would be a bioprospecting in role likely involved in phytoremediation of metal.

Uptake, translocation and impact of green synthesized nanoceria on growth and antioxidant enzymes activity of Solanum lycopersicum L.

Cerium oxide nanoparticles (nanoceria) were synthesized by a novel, simple green chemistry procedure using Elaeagnus angustifolia leaf extract as a reducing and capping agent. The crystalline nature of nanoceria was confirmed by XRD analysis. FTIR analysis revealed that phytochemicals are present on the surface of nanoceria. SEM and TEM images revealed that the nanoceria are well dispersed, spherical in shape with a particle size range in between 30 and 75 nm. Thereafter, the effects of various concentrations of cerium oxide (CeO2) and green synthesized nanoceria on growth and metabolism of Solanum lycopersicum (tomato) were investigated. The bio-accumulation of Ce in tomato seedlings was found to be dose dependent and the results showed that with the increase in exposure concentrations, the accumulation of Ce contents in both root and shoots augmented. However, unlike nanoceria treated seedlings, Ce contents in the roots with CeO2 treatments were negligible than that in the shoots at lower concentrations and this suggested the immobilization of Ce in CeO2 treatment at lower concentrations. Nanoceria at 500 and 1000 mg/L resulted in inhibitory effect on growth of test plant as compared to CeO2 component. The exposure of plants to nanoceria and CeO2 has resulted in significant reduction in pigment content, increased LP, EL and H2O2 content. The activities of antioxidant enzymes viz. SOD, CAT, APX and GPX were significantly up regulated on exposure of nanoceria and CeO2. It is concluded that plant exposure with nanoceria at concentrations of 20 and 100 mg/L were more beneficial for growth and metabolism of tomato plants than that of CeO2 at equivalent concentrations.

First insights into per-and polyfluoroalkyl substance contamination in edible fish species of the Indus water system of Pakistan.

Per- and polyfluoroalkyl substances (PFASs) are a group of emerging contaminants, that have a wide range of applications in industrial and commercial products. The direct discharge of untreated industrial and domestic wastewater into freshwater bodies is a common practice in developing countries, which are the main contributors to PFASs in the aquatic environment. The situation is further worsened due to poor wastewater treatment facilities and weak enforcement of environmental regulations in countries like Pakistan. The current study was designed to assess PFASs contamination in muscle tissues of edible fish species from major tributaries of the Indus System, including Head Panjnad (HP), Head Trimmu (HT), Chashma Barrage (CB), Head Blloki (HB) and Head Qadirabad (HQ). The analysis of target PFAS was performed using ultrahigh-performance liquid chromatography coupled with a quadrupole Orbitrap high-resolution mass spectrometry. The highest levels of ∑17PFASs were observed in S. seenghala, C. mirigala from HB, and C. mirigala from HQ with a mean value of 45.4 ng g-1, 43.7 ng g-1, and 40.8 ng g-1, respectively. Overall, the compositional profile of fish samples was predominated by long-chain PFASs such as PFOA, PFOS, PFHpS, and PFDS. The accumulation of PFASs in fish species is dependent on the physiochemical properties of PFASs, characteristics of the aquatic environment, and fish species. Significant associations of PFASs with isotopic composition (p < 0.05), feeding habits (p < 0.05), and zones (p < 0.05) indicate that dietary proxies could be an important predictor of PFASs distribution among species. The C7-C10 PFASs exhibited bio-accumulative tendency with an accumulation factor ranging from 0.5 to 3.4. However, none of the fish samples had sufficiently high levels of PFOS to cause human health risk (HR < 1). For future studies, it is s recommended to conduct seasonal monitoring and the bioaccumulation pattern along trophic levels of both legacy and emerging PFASs.

Elucidating Heavy Metals Concentration and Distribution in Wild Edible Morels and the Associated Soil at Different Altitudinal Zones of Pakistan: a Health Risk Implications Study.

This study evaluates macro-nutrient (MN) and prevailing heavy metal (HM) concentrations in wild edible morels (WEM) species viz., Morchella crassipes, Morchella pulchella, and Morchella eohespera and the associated soil that were collected from different altitudinal zones (Azad Kashmir, Murree, Swat, and Skardu) of Pakistan. A special emphasis on potential health risk analysis for HM in WEM consumption was also explored. In general, MN concentration in fruiting bodies and their associated soil samples were in the following order: potassium (K) > magnesium (Mg) > calcium (Ca) > sodium (Na) and Ca > Mg > K > Na, respectively. The concentration for HM in WEM ranged between 20.0 and 78.0 mg/kg, 1.09 and 22.1 mg/kg, 2.1 and 22.1 mg/kg, 0.26 and 13.1 mg/kg, 0.43 and 9.1 mg/kg, 1.07 and 7.0 mg/kg, 1.01 and 5.4 mg/kg, and BDL and 3.1 mg/kg for zinc (Zn), copper (Cu), nickel (Ni), manganese (Mn), cobalt (Co), chromium (Cr), lead (Pb), and cadmium (Cd), respectively, and those in underlying soil samples, lowest and highest HM concentration were recorded for Zn (33.7-113.6 mg/kg), Cu (13.0-40.8 mg/kg), Ni (3.1-23.0 mg/kg), Pb (1.3-22.0 mg/kg), Co (2.9-5.6 mg/kg), Cr (2.7-11.1 mg/kg), Mn (2.0-7.1 mg/kg), and Cd (1.1 mg/kg 7.6). Although, Cd, Pb, and Zn concentrations in some of the WEM samples and Cd in the soil had exceeded the permissible limits set by different organizations. The greater accumulation/or transfer potential for Zn, Co, Ni, and Cu were recorded in WEM from their associated soil. The health risk index (HRI) for HM in all assessed samples of WEM was < 1, predicting no risk to the consuming population. Furthermore, the correlation analyses depicted that the power of hydrogen (pH), low organic matter contents, and sandy texture are likely to be responsible for HM transfer to the lower pool of soil. But the increasing concentration of HM in WEM warrants threats and suggests further monitoring and future policy plan and implementation to avoid the potential health risks via its regular consumption.

Consumer health risk assessment from some heavy metal bioaccumulation in common carp (Cyprinus carpio) from lake Koka, Ethiopia.

Heavy metal pollution is a serious problem in Ethiopian rift valley lakes, including Lake Koka, as a result of unmanaged industrial waste pollution. However, the bioaccumulation level in common carp (Cyprinus carpio), a commercially important fish species, are unknown. The aim of this research was, therefore, to assess the heavy metal bioaccumulation in edible parts of common carp in Lake Koka and the associated health risks. Three sampling sites were selected randomly for primary data collection. Four heavy metals (Cd, Cr, Pb and Zn) were analyzed in water and the edible part of the fish using Atomic Absorption Spectroscopy (AAS). The mean concentrations of Zn, Cr and Cd in the edible part of fish ranged from 0.07 to 0.36 mg kg-1, Not Detected (ND)-0.24 mg kg-1 and ND-0.03 mg kg-1, respectively. Site 2 had the highest Zn and Cd content, while Site 3 had the highest Cr content. Pb was however not identified. The amount of Cr was above the permissible limit of FAO and the bioaccumulation showed marked differences among the sampling sites (p < 0.05). The concentrations of Cd, Pb and were below the maximum permissible limit. Cr and Zn had the highest and lowest transfer factor values, respectively. The carcinogenic hazard ratio values were below the threshold value (<1). The estimated weekly intake of heavy metals from fish muscles ranked as Cr > Zn > Cd, but the values were lower than the Reference Dose limit (RfDo). The carcinogenic risk value also indicated a low health risk associated with individual metals intake. Furthermore, the hazard index of the edible part of fish was less than unity. Generally, the water quality is not a risk for the survival and reproduction of fish and the heavy metal contents in the edible parts of fish exhibited low carcinogenic risk through the food chain.

Assessment of industrial effluents for heavy metals concentration and evaluation of grass (Phalaris minor) as a pollution indicator.

This study was conducted to investigate the impact of industrial activities on heavy metals status in wastewater, sludge and flora on the bank of selected main drains of the Hayatabad Industrial estate, Peshawar. Plants, sludge and wastewater samples of selected sites were collected and analyzed for heavy metals distribution; cadmium (Cd), chromium (Cr), lead (Pb) and zinc (Zn) levels. Bioconcentration factor (BCF) values were calculated for plants (Phalaris minor) grass species found naturally at all sites. The results showed that the levels of metals in wastewater were lower than permissible limits except Cd and the concentration of metals in plants and sludge were within permissible limits when compared to their respective standards. Metal distribution was in the following order; sludge > plants > wastewater and the concentration of metals varied according to the distance from the source with no specific pattern. Sludge samples for all sites showed a high concentration of metals as compared to plants and wastewater samples. In grass samples, Zn was highest and Cd was low for all sites. Metals accumulation in plants was in order of; roots > shoot. Pearson's coefficient correlation showed that Cr in plant roots and Zn in shoots showed significantly high correlation with Cd in sludge while Pb in roots showed significant negative correlation with Zn in sludge. BCF values for Cr, Pb and Zn were >1, showing the phytoremediation potential of plants.

Revealing mechanisms of triclosan on the removal and distribution of nitrogen and phosphorus in microalgal-bacterial symbiosis system.

Microalgal-bacterial symbiosis (MABS) system performs synergistic effect on the reduction of nutrients and carbon emissions in the water treatment process. However, antimicrobial agents are frequently detected in water, which influence the performance of MABS system. In this study, triclosan (TCS) was selected to reveal the effects and mechanisms of antimicrobial agents on MABS system. Results showed that the removal efficiencies of chemical oxygen demand, NH4+-N and total phosphorus decreased by 3.0%, 24.0% and 14.3% under TCS stress. In contrast, there were no significant decrease on the removal effect of total nitrogen. Mechanism analysis showed that both the growth rate of microorganisms and the nutrients retention capacity of extracellular polymeric substances were decreased. The intracellular accumulation for nitrogen and phosphorus was promoted due to the increased cytomembrane permeability caused by lipid peroxidation. Moreover, microalgae were dominant in MABS system with ratio between microalgae and bacteria of more than 5.49. The main genus was Parachlorella, with abundance of more than 90%. Parachlorella was highly tolerant to TCS, which might be conductive to maintain its survival. This study revealed the nutrients pathways of MABS system under TCS stress, and helped to optimize the operation of MABS system.

Exposure to environmentally relevant concentrations of TnBP results in tissue-specific bio-accumulation and inhibits growth of silver carp (Hypophthalmichthys molitrix).

Tri-n-butyl phosphate (TnBP) is commonly used as flame retardant and rubber plasticizer, and has been widely detected in aquatic organisms and natural waters. However, the potential toxicity of TnBP in fish remains unclear. In the present study, silver carp (Hypophthalmichthys molitrix) larvae were treated with environmentally relevant concentrations (100 or 1000 ng/L) of TnBP for 60 d and then they were depurated in clean water for 15 d, and the accumulation and depuration of the chemical in six tissues of silver carp were measured. Furthermore, effects on growth were evaluated and potential molecular mechanisms were explored. Results indicated that TnBP could be rapidly accumulated and depurated in silver carp tissues. In addition, the bio-accumulation of TnBP displayed tissue-specificity, where intestine contained the greatest and vertebra had the smallest level of TnBP. Furthermore, exposure to environmentally relevant concentrations of TnBP led to time- and concentration-dependent growth inhibition of silver carp, even though TnBP was completely depurated in tissues. Mechanistic studies suggested that exposure to TnBP up- and down-regulated the expression of ghr and igf1 in liver, respectively, and increased GH contents in plasma of silver carp. TnBP exposure also up-regulated the expression of ugt1ab and dio2 in liver, as well as decreased T4 contents in plasma of silver carp. Our findings provide direct evidence of health hazards of TnBP to fish in natural waters, calling for more attention of environmental risks of TnBP in aquatic environment.

Elucidating the effect and mechanism of the brown coal-based amendment on plant availability of zinc, lead and cadmium in a Haplic Luvisols.

Plants are a key link in the trophic chain and therefore may determine the global circulation of pollutants, including heavy metals (HMs). In the context of sustaining soil functions associated with food safety, the bioavailability of HMs should be reduced to a minimum needed for adequate plant nutrition. The objective of the study was to analyse the bioavailability of zinc, lead and cadmium in phacelia (Phacelia tanacetifolia Benth.) under conditions of varied soil pH and doses of brown coal-based organo-mineral amendment so-called the Rekulter. The experiment was carried out on Haplic Luvisols in field stone pots that sank into the ground, with the following HM content (in mg kg-1 of soil): 90.0 (Zn), 60.4 (Pb) and 0.80 (Cd). The Rekulter was applied to the soil in the amounts of 180, 360 and 720 g per pot. The bio-accumulation index (BI) was calculated as a ratio of a HM content in a plant to its total content in a soil sample, and it was used to evaluate bioavailability. The application of the Rekulter reduced the bioavailability of the studied heavy metals: the lowest BI values were found in the case of Pb. The uptake of HMs by phacelia was the smallest for the highest applied Rekulter dose at a soil pH of approximately 6.0. The bioavailability of Zn, Pb and Cd was influenced by soil pH and organic matter content, reducing their mobility and possible environmental risks. The Rekulter reduced HM bioavailability: the lowest bio-accumulation index (BI) values were found in the case of Pb. The application of the Rekulter into soil improved the physical, chemical and biological properties of soil, including the reduction of contaminant bioavailability.

Bio-accumulation and health risk assessment of heavy metals in different edible fish species from Hurghada City, Red Sea, Egypt.

BACKGROUND: Heavy metal contamination has become a serious issue in this century especially detected in fish organs. Due to the presence of radioactive compounds in agricultural and sewage effluent, which destroys aquatic ecosystems, threatening human livelihoods. Health hazards associated with low and high consumption consumers assessed in five commercial fish species collected from Hurghada City, Egypt, during winter and summer, 2020. Atomic absorption spectrophotometer technique used for determination heavy meals in different organs and expressed as µg/g wet weight. RESULTS: Heavy metal concentrations in muscle ranged between:(0.054-0.109), (0.260-1.043), (0.264-0.897), (5.895-11.898), (0.381-0.970), (13.582-29.133) and (0.332-0.589) µg/g for Cd, Pb, Mn, Zn, Cu, Fe and Ni respectively, which were lower than those of gills and liver. These concentrations were within WHO, FAO/WHO, and EU standards. Consumption of edible species was lower than the (TDIs) established by the (JECFA) and Egyptian Standards. Even though THQ and TTHQ values were < 1 while, in children with highly consumer were> 1. CONCLUSION: This study concluded that intake of Red Sea fish is safe for human health. It is critical for consumers to be aware of the consequences of excessive fish consumption, particularly children with highly consumer, which represent possible health risks.

Severe contamination of carcinogenic heavy metals and metalloid in agroecosystems and their associated health risk assessment.

The contamination of toxic heavy metals (i.e., Cd, Cr, Pb, and Ni) and metalloid (i.e., As) (TMMs) is considered as a major cause of increasing incidences of human and livestock cancers, gastrointestinal disorders and neurological problems. The levels of these TMMS in soil, irrigation water, and plants like Salanum lycopersicum (tomato), Spinacia oleracea (Spinach), and Triticum aestivum (Wheat) samples were detected which were collected from various localities across 100 km around the city of Lucknow, India. This study reported that the concentration of TMMs was within the range of maximum allowable concentration (MAC) (FAO/WHO, 2011) in most of the agricultural soil, whereas, it was higher in irrigation water. The TMMs levels in the edible parts of vegetables and cereal were in the range 1.91-53.94 µg/g, 5.06-40.49 µg/g, 4.08-2312-29 µg/g, 0.43-51.48 µg/g, and 0.01-1.65 µg/g, respectively which was significantly higher than the MAC. The BAF of Cd and Ni was very high in the edible parts of the vegetables and cereal samples indicating an entry of TMMs in food chain through the metal-contaminated irrigation water, even if TMMs are low in the field soil. The contamination coefficient (Cfi) and Ecological risk factors (Efi) of the TMMs were detected in the range of low risk in all agricultural soil. The Ecological risk index (ERI) of TMMs was at moderate risk, indicating a mild impact of the metal toxicity in the agro-ecosystems but the high risk on the consumers. The daily intake (DI) of TMMs through vegetables and cereal was below the maximum allowable daily intake (MTDI) but the carcinogenic risk factor (CRs) potential of Cr, Cd, Ni, and As was observed significantly higher for these vegetables and cereal, which indicated a complex scenario of a far-future carcinogenic health hazard on consumers in densely populated city of Lucknow, India and its surrounding regions.

Periphytic biofilms accumulate manganese, intercepting its emigration from paddy soil.

Manganese (Mn) in acidic paddy soil has large potential in emigrating from the soil and pollute adjacent ecosystems. Single microorganisms modulate the biogeochemistry process of Mn via redox reactions, while the roles of microbial aggregates (e.g. periphytic biofilm) in modulating its biogeochemical cycle is poorly constrained. Here we collected a series of periphytic biofilms from acidic paddy fields in China to explore how periphytic biofilm regulates Mn behavior in paddy fields. We found that periphytic biofilms have large Mn accumulation potential: Mn contents in periphytic biofilm ranged from 176 ± 38 to 797 ± 271 mg/kg, which were 1.2-4.5 folds higher than that in the corresponding soils. Field experiments verified the Mn accumulation potential, underlining the biofilms function as natural barriers to intercept Mn emigrating from soil. Extracellular polymeric substances, especially the protein component, mediated adsorption was the main mechanism behind Mn accumulation by periphytic biofilm. Microorganisms in periphytic biofilms in general appeared to have inhibitory effects on Mn accumulation. Climatic conditions and nutrients in floodwater and soil affect the microorganisms, thus indirectly affecting Mn accumulation in periphytic biofilms. This study provides quantitative information on the extent to which microbial aggregates modulate the biogeochemistry of Mn in paddy fields.

Understanding potentially toxic metal (PTM) induced biotic response in two riparian mangrove species Sonneratia caseolaris and Avicennia officinalis along river Hooghly, India: Implications for sustainable sediment quality management.

Elevated human-induced activities have prompted significant uncontrolled release of potentially toxic metals (PTM) to the undisturbed ecosystem throughout the globe. Riparian mangrove vegetations act as a natural purifier of wastewaters and assist in maintaining a healthy ecosystem. We have investigated the elevated PTM-induced stress and biotic response of two riparian mangrove species e.g. Sonneratia caseolaris and Avicennia officinalis by river Hooghly. The increased PTM concentrations were observed throughout the river bank; with the maximum pollution load at Chemaguri (S9). Except Co, Cr and Pb, higher enrichment factor (1.97-8.89) and contamination factor (0.64-2.88) values were observed for Cd, Cu, Fe, Zn. Mn, and Ni. Geo-accumulation index (-2.2 - 0.92) values indicates natural geogenic accumulation of Cu in the riparian mangrove sediment. Thus, sediment quality indices suggest except Cu, enrichment of all studied PTMs was sourced from anthropogenic activities. The sediment of the region when compared with consensus-based sediment quality guidelines shows considerable ecotoxicological risks and threat towards human health considering Ni accumulation. The highest potential ecological risk index value was observed in Chemaguri (S9). The biotic response of riparian mangroves was characterized by reduced photosyhthetic pigments (Chlorophyll a and Chlorophyll b) and increased activity of antioxidative stress enzymes (POD, CAT and SOD). Significant statistical relationship between antioxidative enzyme activity, photosynthetic pigments and bioaccumulated PTMs reflects active functioning of detoxification mechanism in the riparian mangrove species.

Natural radioactivity levels in benthic foraminifera Sorites marginalis as a pollution indicator.

Sorites marginalis as one of the benthic foraminifer's genera were collected from three coastal lagoons (Abu Shaar, Umm al-Huwaytat, and Marsa Shuni) on the Egyptian Red Sea coast and investigated for their 226Ra, 232Th, and 40K content using HPGe gamma-ray spectrometry. S. marginalis shells show high radioactivity levels with average activity concentration values of 251.8 ± 18.3, 86.8 ± 7.7, and 791.2 ± 57.6 Bq kg-1, 327.1 ± 11.4, 97.4 ± 7.1, and 751.6 ± 54.7 Bq kg-1, 246.6 ± 17.7, 65.1 ± 4.8, and 477.6 ± 34.8 Bq kg-1 for 226Ra, 232Th, and 40K in the samples from Abu Shaar, Umm al-Huwaytat, and Marsa Shuni, respectively. 226Ra and 40K have a high tendency to accumulate in S. marginalis compared to 232Th. High bioaccumulation of the studied radionuclides was found for samples from Umm al-Huwaytat and Abu Shaar lagoons. Radiological parameters such as radium equivalent activity, gamma absorbed dose rate in air, and outdoor annual effective dose were calculated, and values higher than the permissible limits were obtained. Based on the obtained results, the estimation of radioactivity levels in S. marginalis shells may serve as an indicator of marine environment pollution.

Succession of enzymes and microbial biomarkers in the process of vermicomposting: An insight towards valorization of toxic paper mill wastes using Perionyx excavatus (Oligochaeta; Perrier, 1872).

PURPOSE: Main insight of the study was to evaluate the potential of Perionyx excavatus, an indigenous earthworm of India towards bioconversion of toxic paper mill wastes. The study had considered a comprehensive study over succession of different enzymes and microbial biomasses alongside removal of heavy metals to reflect the qualitative enrichment of the toxic waste through valorisation procedure. METHODS: The process of vermicomposting was performed using ratio of paper mill sludge: cow dung: straw as 5:4:1 and Perionyx excavatus for a period of 60 days. Qualitative enrichment was considered through detailed evaluation of physicochemical parameters and succession of 19 enzymes using API ZYM technology. Heavy metal loads in terms of Zn, Cr, Cu, Pb along with bioaccumulation factor (BAF) were considered to establish functional role of earthworm in bioremediation. Microbial succession was measured in terms of PLFA biomarkers. RESULTS: Enzymatic enrichment of different isozymes of esterase, aminopeptidase and glycosyl hydrolase were found in the vermicompost. A significant reduction of heavy metals was noticed in vermicomposting of primary sludge as Zn > Pb > Cr > Cu and secondary sludge as Zn > Pb > Cu > Cr. An increase in density of Gram positive bacterial and fungal populations was found at the end phase of vermicomposting process which supports maturity of vermicompost. CONCLUSION: Presence of different enzyme activities, reduction of heavy metal loads along with rise of eukaryotic PLFA markers, had illustrated the efficiency of vermicomposting as a valorisation procedure in the qualitative enrichment of toxic organic paper mill sludge.

Human health risk from consumption of two common crops grown in polluted soils.

Contamination of agricultural soils by trace elements is a recurrent hazard for human health because of the possibility of pollutants entering the food chain. Aim of this study was to assess the human health risk from consumption of the common leafy (Lactuca sativa L.) and fruit (Cucurbita pepo L.) crops, in an agricultural area of Southern Italy. Along with agricultural practices, a major pollutant source is recurrent flooding from the highly polluted Solofrana river. Soil samples and edible parts of crops from 14 sites (10 flooded and 4 not flooded) were analyzed for total amounts of As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn. The bio-accumulation factor (BAF) and Health Risk Index (HRI) were calculated for each element, crop and site and as average values of all sites (BAFmean and HRImean). Moreover, the Hazard Index (HI) was determined for each site, as the sum of HRI for all elements. Cr and Cu, mostly derived from river flooding and agricultural practices, respectively, were the only elements whose levels exceeded law thresholds and/or the natural background of the study area. Of the two considered crops, L. sativa accumulated more Cd, Cr and Ni, whereas C. pepo was a more effective bioaccumulator of Zn. Both HRImean (for As, Cd, Cr and Ni) and HI were higher for L. sativa than for C. pepo. A low health risk was associated to major soil pollutants (Cr and Cu) found in the study area; in contrast, combined data on soil pollution and plant bio-accumulation points to accumulation of Cd and As, mainly in lettuce, as a potential risk for human health. The results suggest that soil pollution data alone is not sufficient to assess health risk.

Acute and chronic toxicity of cadmium on the copepod Pseudodiaptomus annandalei: A life history traits approach.

We determined the effect of acute and chronic toxicity of cadmium (Cd) on Pseudodiaptomus annandalei, according to their developmental and reproductive stages. Firstly, to estimate the 50% lethal concentration (LC50), acute exposure of nauplii and copepodids to 20, 40, 80, 150, and 300 µg/L of Cd was tested, and the effects of 5 µg/L and 40 µg/L of Cd on copepod developmental rate was done. Female lifespan and number of nauplii produced were compared. Secondly, one generation of copepod was exposed to dissolved (WCd) and dietary (DCd) Cd, and sex-specific Cd uptake and population density were estimated. 96 h LC50 was 40 µg/L Cd for nauplii and 120 µg/L Cd for copepodids. Duration of copepod development was 3.5 days and 5.5 days longer than the control when exposed to 5 µg/L and 40 µg/L of Cd, respectively. Female lifespan in both treatments were 9 and 8 days shorter than in the control, respectively. Total number of nauplii produced per female lifespan was 440 (control), 450 (5 µg/L Cd), and 365 (40 µg/L Cd). Cd uptake in copepods increased from nauplii to adults when exposed to dietary Cd and decreased when exposed to dissolved Cd. Dietary uptake of Cd was significantly higher in males than in females and Cd uptake from water was higher in males than in females, but not statistically significant. The total population of copepods were significantly affected by Cd. The toxic effects of Cd in copepods appear to depend on developmental stage, sex, duration and uptake route.