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1.
Ecotoxicol Environ Saf ; 208: 111755, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396078

RESUMO

Air pollution constitutes potential threats to wildlife and human health; therefore, it must be monitored accurately. However, little attention has been given to understanding the toxicological effects induced by air pollution and the suitability of bird species as bioindicators. The Eurasian tree sparrow (Passer montanus), a human commensal species, was used as a study model to examine toxic metal accumulation, retention of particulate matter (PM), immunological and antioxidant capacities, and hematological parameters in birds inhabiting those areas with relatively higher (Shijiazhuang city) or lower (Chengde city) levels of PM2.5 and PM10 in China. Our results showed that Shijiazhuang birds had significantly more particle retention in the lungs and toxic metal (including aluminum, arsenic, cadmium, iron, manganese, and lead) accumulation in the feathers relative to Chengde birds. They also had lower superoxide dismutase, albumin, immunoglobulin M concentrations in the lung lavage fluid, and total antioxidant capacity (T-AOC) in the lungs and hearts. Furthermore, although they had higher proportions of microcytes, hypochromia, and polychromatic erythrocytes in the peripheral blood (a symptom of anemia), both populations exhibited comparable body conditions, white cell counts, heterophil and lymphocyte ratios, and plasma T-AOC and corticosterone levels. Therefore, our results not only confirmed that Shijiazhuang birds experienced a greater burden from environmental PM and toxic metals but also identified a suite of adverse effects of environmental pollution on immunological, antioxidative, and hematological parameters in multiple tissues. These findings contribute to our understanding of the physiological health consequences induced by PM exposure in wild animals. They suggest that free-living birds inhabiting urban areas could be used as bioindicators for evaluating the adverse effects induced by environmental pollution.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Poluição Ambiental/estatística & dados numéricos , Pardais/fisiologia , Poluentes Atmosféricos , Animais , Animais Selvagens , Antioxidantes , Cádmio , China , Cidades , Biomarcadores Ambientais , Poluição Ambiental/análise , Plumas , Humanos , Material Particulado , Pardais/sangue
2.
Ecotoxicol Environ Saf ; 208: 111768, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396086

RESUMO

Scallops are one of the most common bivalves, large-scale farmed in the coastal areas of China. Three species of scallops (Chlamys farreri, Argopecten irradians and Patinopecten yessoensis) from 10 samples sites along the Bohai Sea and the Yellow Sea were collected to investigate species-specific and tissues-specific bioaccumulation, spatial-temporal distribution and health risks for people. Cd must be paid attention since Cd concentrations in 96% of scallop samples exceeded standard with the highest Cd bioaccumulation potentials (BCF) >10,000 while those of the other metals were less than the corresponding limits except Zn with exceeding-limit percentage of 13%. The metal pollution index values showed that A. irradians could accumulate more metals than the other two species, and scallops in the Bohai Sea were polluted more seriously by heavy metals than in the Yellow Sea. The capacities of tissues in scallops to accumulate metals generally followed the order of digestive gland > gill > adductor muscle. However, Zn accumulated in gill was more than that in digestive gland and muscle. Adults and children would face the non-cancer risks because of the accumulation Cd in scallops based on health risk assessment. Cd was the major contributor of health risk to account for 85% of total hazard quotient and 48% of total cancer risk. Scallops could accumulate Cd rapidly from ambient environments to cause health risks according to the transplantation test. Moreover, the recommended maximum edible amounts of whole scallops were 127/63 g/week for adult/children on the basis of the provisional tolerance weekly intake. Humans are recommended to only consume adductor muscles for reducing health risks.


Assuntos
Aquicultura , Cádmio/análise , Exposição Dietética/estatística & dados numéricos , Metais Pesados/análise , Pectinidae , Poluentes Químicos da Água/análise , Adulto , Animais , Bivalves , Criança , China , Monitoramento Ambiental , Poluição Ambiental , Humanos , Medição de Risco , Alimentos Marinhos/análise , Especificidade da Espécie , Água
3.
Ecotoxicol Environ Saf ; 208: 111769, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396087

RESUMO

Soils contaminated with heavy metals such as Chromium (Cr) and Cadmium (Cd) severely impede plant growth. Several rhizospheric microorganisms support plant growth under heavy metal stress. In this study, Cr and Cd stress was applied to in vitro germinating seedlings of a Legume plant species, Sesbania sesban, and investigated the plant growth potential in presence and absence of Bacillus anthracis PM21 bacterial strain under heavy metal stress. The seedlings were exposed to different concentrations of Cr (25-75 mg/L) and Cd (100-200 mg/L) in Petri plates. Growth curve analysis of B. anthracis PM21 revealed its potential to adapt Cr and Cd stress. The bacteria supported plant growth by exhibiting ACC-deaminase activity (1.57-1.75 µM of α-ketobutyrate/h/mg protein), producing Indole-3-acetic acid (99-119 µM/mL) and exopolysaccharides (2.74-2.98 mg/mL), under heavy metal stress condition. Analysis of variance revealed significant differences in growth parameters between the seedlings with and without bacterial inoculation in metal stress condition. The combined Cr+Cd stress (75 + 200 mg/L) significantly reduced root length (70%), shoot length (24%), dry weight (54%) and fresh weight (57%) as compared to control. Conversely, B. anthracis PM21 inoculation to seedlings significantly increased (p ≤ 0.05) seed germination percentage (5%), root length (31%), shoot length (23%) and photosynthetic pigments (Chlorophyll a: 20%; Chlorophyll b: 16% and total chlorophyll: 18%), as compared to control seedlings without B. anthracis PM21 inoculation. The B. anthracis PM21 inoculation also enhanced activities of antioxidant enzymes, including superoxide dismutase (52%), peroxidase (66%), and catalase (21%), and decreased proline content (56%), electrolyte leakage (50%), and malondialdehyde concentration (46%) in seedlings. The B. anthracis PM21 inoculated seedlings of S. sesban exhibited significantly high (p ≤ 0.05) tissue deposition of Cr (17%) and Cd (16%) as compared to their control counterparts. Findings of the study suggested that B. anthracis PM21 endured metal stress through homeostasis of antioxidant activities, and positively impacted S. sesban growth and biomass. Further experiments in controlled conditions are necessary for investigating phytoremediation potential of S. sesban in metal-contaminated soils in presence of B. anthracis PM21 bacterial strain.


Assuntos
Bacillus anthracis/fisiologia , Metais Pesados/toxicidade , Sesbania/fisiologia , Poluentes do Solo/toxicidade , Bacillus anthracis/metabolismo , Biodegradação Ambiental , Cádmio/metabolismo , Catalase/metabolismo , Clorofila , Clorofila A/metabolismo , Cromo/análise , Germinação/efeitos dos fármacos , Ácidos Indolacéticos , Metais Pesados/análise , Plântula/metabolismo , Sesbania/metabolismo , Sesbania/microbiologia , Solo , Poluentes do Solo/análise
4.
Ecotoxicol Environ Saf ; 208: 111582, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396105

RESUMO

In recent years, heavy metal pollution has caused immeasurable harm to the environment. As an emerging technology, phytoremediation technology has gained a place in the treatment of heavy metal pollution with its unique advantages. This study analyzes the toxic effects of mulberry (Morus alba) seeds, seedling growth and silkworm under heavy metal stress of lead (Pb) and cadmium (Cd), and explore the accumulation and migration of Pb and Cd in the soil-mulberry tree-silkworm system. The main results were as follows: (1) Seed germination and potted seedling experiments were conducted under heavy metal Pb and Cd stresses, and it was found that Pb and Cd had inhibitory effects on mulberry seed germination, growth and photosynthesis of mulberry seedlings, and as the concentration of heavy metals increased, the stronger the inhibitory effect. Moreover, Pb and Cd have a synergistic effect under compound stress. (2) The accumulation and transfer rules of Pb and Cd ions in mulberry were different. The content of Pb in mulberry was root > leaf > stem and the content of Cd was root > stem > leaf. The combined stress promoted the transfer of Pb and Cd from the underground part to the aerial portion of mulberry. (3) The silkworm feeds on mulberry leaves contaminated with heavy metals in this experiment and found that: with the increase of silkworm feeding, the heavy metal content in the silkworm body increased significantly, but the content remained in the silkworm body was less, most of it was excreted with silkworm excrement. Combined stress has no significant effect on the detoxification mechanism of silkworm. It is indispensable to think of the synergistic effect of heavy metals on plants germination when seeds are used for phytoremediation.


Assuntos
Bombyx/fisiologia , Cádmio/toxicidade , Cadeia Alimentar , Chumbo/toxicidade , Morus/fisiologia , Poluentes do Solo/toxicidade , Solo/química , Animais , Biodegradação Ambiental , Cádmio/análise , Cádmio/metabolismo , Frutas/química , Metais Pesados/análise , Fotossíntese , Folhas de Planta/química , Plântula/química , Poluentes do Solo/análise , Poluentes do Solo/metabolismo
5.
Ecotoxicol Environ Saf ; 208: 111584, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396107

RESUMO

Cadmium (Cd) is highly toxic for plant metabolic processes even in low concentration due to higher retention rates, longer half-life and non-biodegradable nature. The current study was designed to assess the bioremediation potential of Cd tolerant PGPR, Serratia sp. CP-13 together with two differentially Cd tolerant maize cultivars (MMRI-Yellow, Sahiwal-2002) selected amongst ten cultivars after screening. The maize cultivars were grown under different Cd treatments (0, 6, 12, 18, 24, 30 µM) in Petri plates both with and without Serratia sp. CP-13 inoculation. Treated plants were analyzed for their biomass accumulation, chlorophylls, carotenoids, proline, anthocyanin, protein, malondialdehyde (MDA), H2O2 as well as for antioxidants (POD, SOD, CAT) and mineral elements (Ca, Mg, Zn, K, Fe, Na, Cd). The maize cultivar MMRI-Yellow (tolerant) and Sahiwal-2002 (sensitive) exhibited significant reduction in leaf area, nutrient contents, plant biomass, activity of antioxidants, total proteins, photosynthetic pigments as well as flavonoids with increased production of H2O2, proline, MDA and relative membrane permeability (RMP) under Cd stress. However, this reduction was cultivar specific and recorded higher in cv. Sahiwal-2002 as compared to MMRI-Yellow. Application of Serratia sp. CP-13 significantly augmented plant biomass, photosynthetic pigments, antioxidative machinery, as well as flavonoids and proline while diminishing H2O2, RMP MDA production even under Cd stress in studied cultivars. Furthermore, CP-13 inoculation assisted the Cd stressed plants to sustain an optimal level of essential nutrients (Ca, Mg, Zn, K, Fe) except for Na and Cd which responded antagonistically. It was inferred that both inoculated maize cultivars exhibited better health and metabolism but substantial Cd tolerance was acquired by the sensitive cv. Sahiwal-2002 than the tolerant cv. MMRI-Yellow under applied Cd regimes. Furthermore, studied maize cultivars depicted maximum Cd tolerance in order of 30 < 24 < 18 < 12 < 6 < 0 µM Cd treatments under Serratia sp. CP-13 inoculation. Findings of current work highlighted the importance of Serratia sp. CP-13 and its inoculation impact on morpho-physio-biochemical attributes of maize growth under Cd dominant environment, which is likely an addition towards efficient approaches for bacterially-assisted Cd bioremediation and minimal Cd retention in edible plant parts.


Assuntos
Cádmio/toxicidade , Serratia/fisiologia , Poluentes do Solo/toxicidade , Zea mays/fisiologia , Antioxidantes/metabolismo , Biodegradação Ambiental , Transporte Biológico , Biomassa , Cádmio/metabolismo , Clorofila/metabolismo , Peróxido de Hidrogênio/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Serratia/metabolismo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Zea mays/metabolismo , Zea mays/microbiologia
6.
Ecotoxicol Environ Saf ; 208: 111591, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396114

RESUMO

The Palaemonid shrimp Palaemon macrodactylus is widely distributed in coastal areas and estuaries which are easily contaminated by various pollutants. However, the responses of this species to environmental toxicants are not well described. In the present study, adult individuals of P. macrodactylus were exposed to gradient concentrations of Cadmium (Cd) to evaluate its acute toxic effects, including bioaccumulation, induced oxidative stress and changed energy metabolism in this species. The medium lethal concentration (LC50) of Cd at 24 h, 48 h, 72 h, and 96 h were 2.60, 0.88, 0.49 and 0.37 mg/L, respectively. Cd bioaccumulations in tissues of shrimp increased in a concentration-dependent manner, and higher concentration (50% 96 h-LC50, 0.185 mg/L) of Cd exposure led to a maximum increase of Cd concentration by 14.8, 145.5 and 15.8 folds in gill, hepatopancreas and abdominal muscle. Cd exposure caused a significant inhibition on the activity of catalase (CAT), and total superoxide dismutase (T-SOD), decrease in the total antioxidant capacity (T-AOC), and an increase of malonadehyde (MDA) content, which indicated a damage to the antioxidant system of shrimp. Meanwhile, Cd exposure also led to a significant up-regulation in the expression level of metallothionein gene (MT), and down-regulations at the mRNA level of heat shock protein 70 (HSP70) and CAT. Moreover, Cd exposure significantly inhibited the oxygen consumption rate (22%), and increased the ammonia excretion rate (43%), hence lead to a significant decrease of the O:N ratio (45%) in shrimp. The results indicated that Cd exposure could induce obvious oxidative stress, energy metabolic dysfunction and bioaccumulation of Cd in P. macrodactylus. The data obtained from the present study would provide useful information for further understanding on the toxicological mechanism of Cd to crustaceans in coastal areas and estuaries.


Assuntos
Cádmio/toxicidade , Palaemonidae/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Bioacumulação , Catalase/metabolismo , Estuários , Brânquias/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Hepatopâncreas/metabolismo , Metalotioneína/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Palaemonidae/metabolismo , Superóxido Dismutase/metabolismo
7.
Ecotoxicol Environ Saf ; 208: 111600, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396120

RESUMO

Field experiments was conducted to evaluate the effectiveness of sepiolite (S), sepiolite + fungi residues (SFR) and sepiolite + vermicompost (SVC) on in situ immobilization remediation of Cd contaminated soils. The results showed that treatments of S, SFR and SVC decreased soil Cd availability by 15.2-47.8%, 17.5-44.9% and 13.2-44.9%, respectively, when compared with the control groups. Moreover, the content of Cd in edible parts of Lactuca sativa L., Cichorium endivia L. and Brassica campestris L. was experienced a decrease of 15.9-41.9%, 1.6-38.0% and 29.0-37.4% reduction, respectively, under the amended soil. The improvement of soil fertility was obtained under addition of SVC and SFR, while the amounts of available P, K, organic matter, microbial carbon, microbial nitrogen and dehydrogenase activity were increased by 9.6-68.2%, 1.2-28.3%, 37.5-70.5%, 4.1-121.0%, 220-640% and 6.8-56.8%, respectively, in contrast to CK. Moreover, high-throughput sequencing analysis showed that the combined treated soils got higher values of alpha diversity indices, Chao1, ACE and Shannon. The number of dominant phyla (Proteobacteria, Acidobacteria, Gemmatimonadetes, Crenarchaeota) and genera (Aquicella, Lysobacter, Candidatus Nitrososphaera, Sphingopyxis, Mesorhizobium) were enhanced. Therefore, the use of sepiolite and organic amendments could be an adequate strategy to immobilization remediation of Cd-contaminated soils.


Assuntos
Cádmio/análise , Recuperação e Remediação Ambiental , Poluentes do Solo/análise , Brassica , Poluição Ambiental , Silicatos de Magnésio , Solo/química , Microbiologia do Solo
8.
Ecotoxicol Environ Saf ; 208: 111731, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396062

RESUMO

Cadmium (Cd) is an environmental toxicant and a nonessential metal. Cd can attack a wide range of organs, such as the liver, kidney, lung, ovary, testis, brain, and muscle in vertebrates. Among these organs, the testis might be the most sensitive organ to Cd toxicity. Metallothionein (MT) is a cysteine-rich protein with a low molecular weight, that can bind with Cd and eliminate reactive oxygen species (ROSs). Hydrogen peroxide, which as a crucial type of ROS that is induced by Cd, can be eliminated by catalase (CAT) in the self-protection of cells and to realize Cd toxicity resistance. To investigate the functions of MT and CAT in the testis of Cynops orientalis, we cloned the full-length MT and CAT genes of C. orientalis for the first time. Immunofluorescence results demonstrated that MT and CAT were expressed in Sertoli cells and all spermatogenic cells in the testis of C. orientalis. The results of the ultrastructural damage assay demonstrated that there were various impairments, which included organelle vacuolization, abnormal chromatin distribution, and apoptotic bodies, in somatic cells that were exposed to Cd. However, the anomalies of spermatozoa were located mainly in the mid-piece and head, many of which showed severely impaired structures. The results demonstrated that MT and CAT expression had distinct patterns in response to various Cd concentrations: an increase in MT mRNA levels with elevated Cd levels and a persistent increase in CAT mRNA levels with elevated Cd levels. These results suggested that MT and CAT play roles in Cd toxicity resistance in the testis and that the expression of CAT may be a better biomarker than the expression of MT for assessing Cd pollution.


Assuntos
Cádmio/toxicidade , Catalase/metabolismo , Clonagem Molecular , Substâncias Perigosas/toxicidade , Metalotioneína/metabolismo , Salamandridae/fisiologia , Testículo/efeitos dos fármacos , Animais , Sequência de Bases , Humanos , Fígado/metabolismo , Masculino , RNA Mensageiro/metabolismo , Salamandridae/genética , Salamandridae/metabolismo , Células de Sertoli/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo
9.
Ecotoxicol Environ Saf ; 208: 111743, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396069

RESUMO

Autophagy dysregulation plays a pivotal role in cadmium (Cd)-induced nephrotoxicity. Quercetin (Qu), a flavonoid antioxidant with autophagy-enhancing effect, has protective effect on Cd-induced toxicity, but whether it can prevent Cd-induced nephrotoxicity via restoration of autophagy remains unknown. Here, primary rat proximal tubular (rPT) cells were exposed to Cd and/or Qu in vitro to clarify this issue. Data first showed that Cd-impaired autophagic flux was markedly alleviated by Qu, including decreased levels of autophagy marker proteins and recovery of autophagosome-lysosome fusion targeted for lysosomes. Meanwhile, Cd-induced lysosomal alkalization due to v-ATPases inhibition was prominently recovered by Qu. Accordingly, Qu enhanced Cd-diminished lysosomal degradation capacity and lysosome-related gene transcription levels. Notably, Qu improved Cd-inhibited TFEB nuclear translocation and its gene transcription level. Furthermore, data showed that the restoration of Cd-impaired autophagy-lysosome pathway and resultant alleviation of cytotoxicity by Qu are TFEB-dependent using TFEB gene silencing and overexpression technologies. In summary, these data provide novel evidences that the protective action of Qu against Cd-induced autophagy inhibition is attributed to its restoration of lysosomal dysfunction, which is dependent on TFEB.


Assuntos
Cádmio/toxicidade , Substâncias Protetoras/farmacologia , Quercetina/farmacologia , Animais , Autofagia/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Epiteliais , Lisossomos/efeitos dos fármacos , Ratos
10.
Ecotoxicol Environ Saf ; 208: 111627, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396147

RESUMO

A pot study was conducted to explore the effectiveness of zinc oxide nanoparticles (ZnO NPs) foliar exposure on growth and development of wheat, zinc (Zn) and cadmium (Cd) uptake in Cd-contaminated soil under various moisture conditions. Four different levels (0, 25, 50, 100 mg/L) of these NPs were foliar-applied at different time periods during the growth of wheat. Two soil moisture regimes (70% and 35% of water holding capacity) were maintained from 6 weeks of germination till plant harvesting. The results revealed that the growth of wheat increased with ZnO NPs treatments. The best results were found in 100 mg/L ZnO NPs under normal moisture level. The lowest Cd and highest Zn concentrations were also examined when 100 mg/L NPs were applied without water deficit stress. In grain, Cd concentrations decreased by 26%, 81% and 87% in normal moisture while in water deficit conditions, the Cd concentrations decreased by 35%, 66% and 81% compared to control treatment when ZnO NPs were used at 25, 50 and 100 mg/L. The foliar exposure of ZnO NPs boosted up the leaf chlorophyll contents and also decreased the oxidative stress and enhanced the leaf superoxide dismutase and peroxidase activities than the control. It can be suggested that foliar use of ZnO NPs might be an efficient way for increasing wheat growth and yield with maximum Zn and minimum Cd contents under drought stress while decreasing the chances of NPs movement to other environmental compartment which may be possible in soil applied NPs.


Assuntos
Cádmio/toxicidade , Secas , Nanopartículas/química , Poluentes do Solo/toxicidade , Triticum/fisiologia , Óxido de Zinco/química , Cádmio/análise , Clorofila , Grão Comestível/química , Poluição Ambiental , Estresse Oxidativo , Folhas de Planta/química , Solo , Poluentes do Solo/análise , Triticum/crescimento & desenvolvimento , Água , Zinco/análise
11.
Ecotoxicol Environ Saf ; 208: 111628, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396148

RESUMO

Metals may cause damage to the biota of contaminated environments. Moreover, using multiple endpoints in ecotoxicological studies is useful to better elucidate the mechanisms of toxicity of these compounds. Therefore, this study aimed to evaluate the effects of cadmium (Cd) and cobalt (Co) on growth, biochemical and photosynthetic parameters of the microalgae Raphidocelis subcapitata, through quantification of lipid classes composition, chlorophyll a (Chl a) content, maximum (ΦM) and effective (Φ'M) quantum yields and efficiency of the oxygen-evolving complex (OEC). Both metals affected the algal population growth, with an IC50-96h of 0.67 and 1.53 µM of Cd and Co, respectively. Moreover, the metals led to an increase in the total lipid content and reduced efficiency of OEC and ΦM. Cell density was the most sensitive endpoint to detect Cd toxicity after 96 h of treatment. Regarding Co, the photosynthetic parameters were the most affected and the total lipid content was the most sensitive endpoint as it was altered by the exposure to this metal in all concentrations. Cd led to increased contents of the lipid class wax esters (0.89 µM) and phospholipids (PL - at 0.89 and 1.11 µM) and decreased values of triglycerides (at 0.22 µM) and acetone-mobile polar lipids (AMPL - at 0.44 and 1.11 µM). The percentage of free fatty acids (FFA) and PL of microalgae exposed to Co increased, whereas AMPL decreased in all concentrations tested. We were able to detect differences between the toxicity mechanisms of each metal, especially how Co interferes in the microalgae at a biochemical level. Furthermore, to the best of our knowledge, this is the first study reporting Co effects in lipid classes of a freshwater Chlorophyceae. The damage caused by Cd and Co may reach higher trophic levels, causing potential damage to the aquatic communities as microalgae are primary producers and the base of the food chain.


Assuntos
Cádmio/toxicidade , Clorofíceas/fisiologia , Cobalto/toxicidade , Poluentes Químicos da Água/toxicidade , Clorofíceas/efeitos dos fármacos , Clorofila A , Ecotoxicologia , Água Doce/química , Metais/farmacologia , Microalgas/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II
12.
Environ Sci Pollut Res Int ; 28(2): 2468-2478, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32888150

RESUMO

The study was carried out to evaluate the health risks associated with accumulation of cadmium in the different genotypes of wheat, grown in agricultural regions of Punjab, Pakistan. Five genotypes irrigated with three varied water sources were selected randomly from each region. Among all sources of water, types of soil, and grain samples, the cadmium (Cd) quantities were found (2.24-2.82 mg/L, 1.75-4.16 mg/kg, 0.86-1.90, respectively), exceeding the maximum permissible limits (0.01 mg/L, 1.1 mg/kg, 0.2 mg/kg, respectively) described by FAO/WHO. The pollution load index (PLI) exhibited by all of the samples was higher than 1.00, the permissible limit; however, other factors including bioaccumulation, translocation, bio-concentration, daily intake, and enrichment values of Cd were less than 1.00. Moreover, the health risk index for cadmium in all types of wheat grain samples was less than 1.00. The study concluded that the continuous use of wastewater resources may lead to the accumulation of cadmium in the vital body organs that may cause severe health hazards.


Assuntos
Metais Pesados , Poluentes do Solo , Bioacumulação , Cádmio/análise , Genótipo , Metais Pesados/análise , Paquistão , Solo , Poluentes do Solo/análise , Triticum/genética , Água
13.
Ecotoxicol Environ Saf ; 208: 111441, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33038726

RESUMO

Soil heavy metal contamination is an increasingly urgent problem throughout the world. Phytoremediation is a cost-effective and ecologically friendly in situ method for the remediation of heavy metal contaminated soils. Rice has the potential for use in soil remediation due to its high biomass production, however, risks related to food safety and low accumulation potential exist. Therefore, in the current study, rice stubble was used as the adsorbent in a modified rice-fish system (MRFS) to assess its accumulation capacity in a model paddy field dosed with 0-40.0 mg kg-1 Cd. The weighted mean concentration (WMC) of Cd in rice stubble increased from 0.498 to 36.365 mg kg-1 to 1.038-71.180 mg kg-1 from 0 to 60 days post-harvest (dph), and the corresponding increment rate was 107.68%, 117.42%, 157.77% and 95.73%, respectively. Sixty-days post-harvest, removal rate of Cd from contaminated soils was 1.11-1.40%, which was greater than that of the Cd-hyperaccumulator Thlaspi caerulescens. The WMC of the heavy metals Cd, Zn, Pb, Cr and Cu in rice stubble increased 51.11-97.50%, and removal rate was 1.93-2.66%. Overall, rice stubble had a high capacity of heavy metal accumulation, mainly benefiting from the synthesis effects of MRFS and the changes of accumulation mechanism within the plant from being alive until death. Notably, this study also provides a new idea for in situ, herbage-based phytoremediation of heavy metal-contaminated soils.


Assuntos
Agricultura , Biodegradação Ambiental , Cádmio/toxicidade , Oryza/fisiologia , Poluentes do Solo/toxicidade , Adsorção , Biomassa , Brassicaceae , Cádmio/análise , Metais Pesados/análise , Solo , Poluentes do Solo/análise
14.
Ecotoxicol Environ Saf ; 208: 111433, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33068977

RESUMO

Evidence from previous studies has shown that exposure to metals is associated with cardiovascular disease (CVD). However, the association between metal mixtures and CVD risk and the potential mechanisms in epidemiologic studies remain unclear. The data of 14,795 adults who participated in the U.S. National Health and Nutrition Examination Survey (NHANES) 1999-2016 were analyzed. Multivariate logistic regression was performed to investigate the associations between urinary metal levels and CVDs. Weighted quantile sum (WQS) regression was performed to examine the effects of mixed metals on CVDs. Multivariate linear regression and mediation analysis were conducted to explore the associations between metals and blood lipids. Urinary cadmium (Cd) was significantly associated with an increased total CVD risk and with individual CVD risk. The odds ratio (OR) for CVD in the highest quartile of the WQS index was 1.43 (95% confidence interval [CI]: 1.19, 1.71). One augmented urinary Cd concentration unit (Log10) was associated with a 0.93 mg/dL decrease in HDL cholesterol, a 1.34 mg/dL increase in LDL cholesterol and a 1.30 mg/dL increase in total cholesterol in the fully adjusted model. Mediation analysis showed that HDL cholesterol mediated 4.91% of the association between urinary Cd and the prevalence of CVD. Our findings suggest that urinary Cd and metal mixtures were significantly and positively associated with CVD. The downregulation of HDL cholesterol might play a significant role in mediating Cd exposure-associated CVD risk increases.


Assuntos
Cádmio/urina , Doenças Cardiovasculares/epidemiologia , HDL-Colesterol/sangue , Exposição Ambiental/estatística & dados numéricos , Adulto , Doenças Cardiovasculares/urina , Feminino , Humanos , Modelos Lineares , Lipídeos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Razão de Chances , Prevalência , Fatores de Risco
15.
Environ Pollut ; 269: 116097, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33246768

RESUMO

Populations of plants and animals, including humans, living in close proximity to abandoned uranium mine sites are vulnerable to uranium exposure through drainage into nearby waterways, soil accumulation, and blowing dust from surface soils. Little is known about how the environmental impact of uranium exposure alters the health of human populations in proximity to mine sites, so we used developmental zebrafish (Danio rerio) to investigate uranium toxicity. Fish are a sensitive target for modeling uranium toxicity, and previous studies report altered reproductive capacity, enhanced DNA damage, and gene expression changes in fish exposed to uranium. In our study, dechorionated zebrafish embryos were exposed to a concentration range of uranyl acetate (UA) from 0 to 3000 µg/L for body burden measurements and developmental toxicity assessments. Uranium was taken up in a concentration-dependent manner by 48 and 120 h post fertilization (hpf)-zebrafish without evidence of bioaccumulation. Exposure to UA was not associated with teratogenic outcomes or 24 hpf behavioral effects, but larvae at 120 hpf exhibited a significant hypoactive photomotor response associated with exposure to 3 µg/L UA which suggested potential neurotoxicity. To our knowledge, this is the first time that uranium has been associated with behavioral effects in an aquatic organism. These results were compared to potential metal co-contaminants using the same exposure paradigm. Similar to uranium exposure, lead, cadmium, and iron significantly altered neurobehavioral outcomes in 120-hpf zebrafish without inducing significant teratogenicity. Our study informs concerns about the potential impacts of developmental exposure to uranium on childhood neurobehavioral outcomes. This work also sets the stage for future, environmentally relevant metal mixture studies. Summary Uranium exposure to developing zebrafish causes hypoactive larval swimming behavior similar to the effect of other commonly occurring metals in uranium mine sites. This is the first time that uranium exposure has been associated with altered neurobehavioral effects in any aquatic organism.


Assuntos
Urânio , Poluentes Químicos da Água , Animais , Cádmio , Criança , Embrião não Mamífero , Humanos , Ferro , Larva , Urânio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
16.
Toxicol Lett ; 337: 38-45, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33246043

RESUMO

Cadmium (Cd) is a toxic heavy metal that when absorbed into the body causes nephrotoxicity and effects in other tissues.Anatomical barrier tissues are tissues that prevent the entry of pathogens and include skin, mucus membranes and the immune system. The adverse effects of Cd-induced immune cell's activity are the most extensively studied in the kidneys and the liver. There are though fewer data relating the effect of this metal on the other tissues, particularly in those in which cells of the immune system form local circuits of tissue defense, maintaining immune-mediated homeostasis. In this work, data on the direct and indirect effects of Cd on anatomical barrier tissue of inner and outer body surfaces (the lungs, gut, reproductive organs, and skin) were summarized.


Assuntos
Cádmio/toxicidade , Homeostase/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Animais , Intoxicação por Cádmio/imunologia , Humanos
17.
Sci Total Environ ; 758: 143616, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33218808

RESUMO

There is limited evidence on the relationships between plasma levels of multiple metals and risk of incident cancer in patients with type 2 diabetes mellitus (T2DM). We examined the associations between plasma levels of 12 metals (iron, copper, zinc, selenium, chromium, manganese, molybdenum, cobalt, nickel, arsenic, cadmium, and lead) and cancer risk in 4573 T2DM patients using Cox proportional hazards models. With a median follow-up of 10.2 years, 541 incident cancers were identified. The multiple-metals model revealed that each 1-SD increase in ln-transformed plasma copper (HR: 1.14; 95%CI: 1.02, 1.27) and lead (HR:1.20; 95%CI:1.03, 1.39) were significantly associated with increased cancer incidence while each 1-SD increase in ln-transformed plasma zinc (HR: 0.82; 95%CI: 0.71, 0.96) and chromium (HR: 0.88; 95%CI: 0.82, 0.94) were significantly associated with decreased cancer incidence. When all participants were further stratified into four subgroups by the quartile levels (Q1-4) of plasma metals, manganese showed significant positive associations with cancer incidence in the upper two quartiles (P trend = 0.003) while nickel showed significant negative associations with cancer incidence in Q2 and 4 groups (P trend = 0.033) compared with participants in Q1 group. Collectively, monitoring of metal levels in diabetic patients needs to be strengthened, which is of great significance for the prevention of incident cancer.


Assuntos
Diabetes Mellitus Tipo 2 , Neoplasias , Cádmio , Cobre , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Incidência , Metais , Neoplasias/epidemiologia , Plasma
18.
Sci Total Environ ; 758: 143583, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33243496

RESUMO

Preschool children are exposed daily to metals in their homes and at daycare centers (DCC). Metal exposure and health effects are associated even at low levels, and children comprise a group of public health concern. Nail metals have been studied for exposure biomonitoring and compared to other biological media. The aim of this study was to explore the applicability of preschool fingernail lead and cadmium as subchronic exposure biomarkers. Nail lead and cadmium levels (NLL and NCL) of 602 preschool children (age: 1-4 years) who attended 21 DCC in São Paulo, Brazil, in 2013 were analyzed. Results were compared against blood lead and cadmium levels (BLL and BCL) found in a previous study. Inductively coupled plasma mass spectrometry (ICP-MS) analyses were performed for both samples. DCC and metal contaminated sites (MCS) were georeferencing. Logistic regression tests were applied to verify associations between nail metal levels and risk factors (sex, age, maternal education, secondary smoking, DCC geographic district, vehicle flow density, relative altitude and distance between DCC and nearest MCS) (p < 0.05). BLL was stratified by exposure level (low: <5 µg.dL-1; high: >13.9 µg.dL-1; medium: ≥5 µg.dL-1 and ≤13.9 µg.dL-1) and also tested the associations in order to verify if nail lead levels are affected by exposure intensity defined by blood metals concentrations. Radius distance and relative altitude of DCC to nearest MCS were associated with high NLL and NCL. Abnormal appearance of nails was associated with high NLL and low NCL. Lead and cadmium exposure magnitude had no significant impact on NLL. NLL should only be used for initial screening, and when financial resources are scarce, especially in areas located near contaminated sites. Preschool children were co-exposed to both lead and cadmium, reinforcing the need for broader studies evaluating exposure to environmental pollutants for more than one chemical element.


Assuntos
Poluentes Ambientais , Chumbo , Biomarcadores , Brasil , Cádmio , Pré-Escolar , Exposição Ambiental , Humanos , Lactente , Unhas
19.
Sci Total Environ ; 758: 143596, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33243504

RESUMO

Cadmium (Cd) contamination in agricultural soils is a widespread environmental problem that can affect food safety and human health. Effective remediation methods are needed to reduce Cd bioavailability in soil and Cd accumulation in food crops. In the present study, we isolated a Cd-resistant and alkalizing bacterium strain XT-4 from a Cd-contaminated soil and evaluated its potential application in Cd bioremediation. Based on its morphological, physiological and biochemical characteristics, together with 16S rRNA gene sequence analysis, strain XT-4 was identified as a member of the Bacillus genus. Strain XT-4 showed a strong ability to increase the pH and decrease Cd solubility in the medium. A greenhouse-based pot experiment with a Cd-contaminated soil was conducted to evaluate the effect of strain XT-4 inoculation on the growth and Cd accumulation of the vegetable Pak choi (Brassica rapa ssp. chinensis). Inoculation increased the rhizosphere pH, decreased CaCl2-extractable Cd in the soil and decreased Cd concentration in the edible part of Pak choi by 28-40%. The results suggest that inoculation with alkalizing bacterial strain XT-4 represents an effective solution to increase rhizosphere pH and decrease Cd uptake by vegetable crops in Cd-contaminated acid soils.


Assuntos
Cádmio , Poluentes do Solo , Disponibilidade Biológica , Cádmio/análise , Humanos , RNA Ribossômico 16S/genética , Solo , Poluentes do Solo/análise , Verduras
20.
Toxicology ; 447: 152631, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33188856

RESUMO

Cadmium (Cd) is recognized as a highly toxic heavy metal for humans in part because it is a multi-organ carcinogen. To clarify the mechanism of Cd carcinogenicity, we have established an experimental system using rat liver TRL1215 cells exposed to 2.5 µM Cd for 10 weeks and then cultured in Cd-free medium for an additional 4 weeks (total 14 weeks). Recently, we demonstrated, by using this experimental system, that 1) Cd stimulates cell invasion by suppression of apolipoprotein E (ApoE) expression, and 2) Cd induces DNA hypermethylation of the regulatory region of the ApoE gene. However, the underlying mechanism(s) as well as other potential genetic participants in the Cd-stimulated invasion are undefined. In the present work, we found that concurrent with enhanced invasion, Cd induced oxidative stress, coupled with the production of oxidative stress-sensitive metallothionein 2A (MT2A), which lead to down-modulation of ten-eleven translocation methylcytosine dioxygenase 1 (TET1: DNA demethylation) in addition to ApoE, without impacting DNA methyltransferases (DNMTs: DNA methylation) levels. Furthermore, the expression of tissue inhibitor of metalloproteinase 2 and 3 (TIMP2 and TIMP3) that are positively regulated by TET1, were decreased by Cd. The genes (ApoE/TET1/TIMP2/TIMP3) suppressed by Cd were further suppressed by hydroquinone (HQ; a reactive oxygen species [ROS] producer), whereas N-acetyl-l-cysteine (NAC; a ROS scavenger) prevented the suppression of their expression by HQ. In addition, NAC reversed their expression suppressed by Cd. Cd-stimulated cell invasion was clearly dampened by NAC in a concentration-dependent manner. Overall these findings suggest that 1) altered TET1 expression and activity together with ApoE are likely involved in the enhanced invasiveness due to Cd exposure, and 2) Cd down-regulation of TET1 likely evokes a reduction in ApoE expression (possible by DNA hypermethylation), and 3) anti-oxidants are effective in abrogation of the enhanced invasiveness that occurs concurrently with Cd-induced malignant transformation.


Assuntos
Cádmio/toxicidade , Dioxigenases/antagonistas & inibidores , Dioxigenases/biossíntese , Fígado/efeitos dos fármacos , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/fisiologia , Relação Dose-Resposta a Droga , Fígado/patologia , Invasividade Neoplásica/patologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Endogâmicos F344
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