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1.
Ecotoxicol Environ Saf ; 191: 110172, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31978762

RESUMO

The majority of pharmaceuticals and personal health-care products are ionisable molecules at environmentally relevant pHs. The ionization state of these molecules in freshwater ecosystems may influence their toxicity potential to aquatic organisms. In this study we evaluated to what extent varying pH conditions may influence the toxicity of the antibiotic enrofloxacin (ENR) and the personal care product ingredient triclosan (TCS) to three freshwater invertebrates: the ephemeropteran Cloeon dipterum, the amphipod Gammarus pulex and the snail Physella acuta. Acute toxicity tests were performed by adjusting the water pH to four nominal levels: 6.5, 7.0, 7.5 and 8.0. Furthermore, we tested the efficiency of three toxicity models with different assumptions regarding the uptake and toxicity potential of ionisable chemicals with the experimental data produced in this study. The results of the toxicity tests indicate that pH fluctuations of only 1.5 units can influence EC50-48 h and EC50-96 h values by a factor of 1.4-2.7. Overall, the model that only focuses on the fraction of neutral chemical and the model that takes into account ion-trapping of the test molecules showed the best performance, although present limitations to perform risk assessments across a wide pH range (i.e., well above or below the substance pKa). Under such conditions, the model that takes into account the toxicity of the neutral and the ionized chemical form is preferred. The results of this study show that pH fluctuations can have a considerable influence on toxicity thresholds, and should therefore be taken into account for the risk assessment of ionisable pharmaceuticals and personal health-care products. Based on our results, an assessment factor of at least three should be used to account for toxicity differences between standard laboratory and field pH conditions. The models evaluated here can be used to perform refined risk assessments by taking into account the influence of temporal and spatial pH fluctuations on aquatic toxicity.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Cosméticos/toxicidade , Água Doce/química , Preparações Farmacêuticas/química , Poluentes Químicos da Água/toxicidade , Anfípodes/efeitos dos fármacos , Animais , Cosméticos/química , Ecossistema , Enrofloxacina/química , Enrofloxacina/toxicidade , Concentração de Íons de Hidrogênio , Modelos Teóricos , Medição de Risco , Caramujos/efeitos dos fármacos , Testes de Toxicidade , Triclosan/química , Triclosan/toxicidade , Poluentes Químicos da Água/química
2.
Pestic Biochem Physiol ; 160: 136-145, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31519248

RESUMO

We studied the molluscicidal activity of Chimonanthus nitens extracts on Pomacea canaliculata (Ampullariidae). The degree of hepatopancreatic tissue damage, and its physiological and biochemical effects, was evaluated on individuals exposed to petroleum ether extracts (PEEEs). The PEEEs, ethyl acetate extract (EAEE) and water saturated n-butyl extract (SBEE) of C. nitens also had toxic effects on P. canaliculata but PEEE had the greatest molluscicidal activity. After exposure to PEEE for 24 h, the hepatopancreas of P. canaliculata had a large necrotic area. The levels of soluble sugar, soluble protein and albumin (Alb) in the hepatopancreas of P. canaliculata decreased with increasing PEEE concentration, while the activities of glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT) and acetylcholinesterase (AchE) increased with increasing PEEE concentration. A total of 29 compounds were identified from the PEEE of C. nitens by gas chromatography-mass spectrometry analysis. The main components were esters (48.13%), alcohols (18.43%) and the compound Chimonanthine (14.70%). The results of the molluscicidal assay, histological experiments and the physiological and biochemical experiments show that the PEEE of C. nitens could potentially be used for P. canaliculata management.


Assuntos
Calycanthaceae/química , Flores/química , Extratos Vegetais/toxicidade , Caramujos/efeitos dos fármacos , Animais , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/enzimologia , Hepatopâncreas/metabolismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
3.
Invert Neurosci ; 19(3): 7, 2019 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-31352500

RESUMO

Biomphalaria alexandrina and Lymnaea natalensis snails are the intermediate hosts of schistosomiasis and fasciolosis. The aim of the present study is to evaluate the molluscicidal activity of chlorophyll extract as a photodynamic substance against these snails and how it affected its tissues and the biological system. Chlorophyllin was extracted from deep-frozen Moringa oleifera leaves, and then it was transformed into water-soluble chlorophyllin. The present results showed that it had a molluscicidal activity on B. alexandrina snails (LC50 17.6 mg/l; LC90 20.9 mg/l) and L. natalensis snails (LC50 4.3 mg/l; LC90 6.8 mg/l). Exposing B. alexandrina snails to the sublethal concentrations (LC0, LC10, and LC25) resulted in a significant reduction in their survival rates. Regarding its effect on biochemical parameters, chlorophyllin significantly reduced the acetylcholinesterase activity, protein content, and alkaline and acid phosphatase activity in B. alexandrina nervous tissue compared to the control group. Histopathological changes occurred in the digestive gland of treated B. alexandrina snails where cells lost their nuclei, vacuolated, degenerated, and ruptured, and the lumen increased. Photosynthesizing materials like chlorophyllin are new approaches to control schistosomiasis and fasciolosis in developing countries by affecting their intermediate host. These materials were cheap and environmentally safe to replace the synthetic molluscicides for snail control.


Assuntos
Clorofilídios/toxicidade , Moluscocidas/toxicidade , Caramujos/efeitos dos fármacos , Animais , Vetores de Doenças , Fasciolíase/prevenção & controle , Extratos Vegetais/toxicidade , Esquistossomose/prevenção & controle
4.
Trans R Soc Trop Med Hyg ; 113(1): 1-3, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31222345

RESUMO

A paper published in 1990 by Webbe and El Hag described the progress being made in the control of schistosomiasis with the introduction of a new medicine 'Praziquantel' to treat infected individuals, and the use of a molluscicide 'niclosamide', with which to kill the intermediate host snails. Almost 30 years from the date of publication, the situation in Egypt and indeed globally has changed out of all recognition. Almost every country in Africa has a school health programme to deworm children, each country has a national plan which includes school health, and praziquantel is now donated through the World Health Organization for countries to treat school aged children to protect them from the serious consequences of chronic schistosomiasis. As the socio-economic status in Africa improves the chances seem good for elimination of schistosomiasis as a public health problem in most areas in Africa.


Assuntos
Anti-Helmínticos/uso terapêutico , Niclosamida/farmacologia , Praziquantel/uso terapêutico , Saúde Pública , Schistosoma/efeitos dos fármacos , Esquistossomose/prevenção & controle , Caramujos/efeitos dos fármacos , África , Animais , Anti-Helmínticos/farmacologia , Criança , Vetores de Doenças , Egito , Humanos , Cooperação Internacional , Moluscocidas/farmacologia , Praziquantel/farmacologia , Esquistossomose/tratamento farmacológico , Esquistossomose/transmissão , Serviços de Saúde Escolar
5.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(2): 107-108, 2019 May 21.
Artigo em Chinês | MEDLINE | ID: mdl-31184037

RESUMO

Oncomelania hupensis is the only intermediate host of Schistosoma japonicum, and control of Oncomelania snails is an important measure to control and interrupt the transmission of schistosomiasis. Therefore, snail control plays a very critical role in the national schistosomiasis control programmes of China. Pyriclobenzuron, which was recently developed by National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, is the latest great advance in the research on molluscicides and is expected to solve the problem of toxicity to fish, which is worthy of expanding experiments.


Assuntos
Erradicação de Doenças , Moluscocidas/toxicidade , Compostos Orgânicos/toxicidade , Esquistossomose , Caramujos , Animais , China , Pesquisa/tendências , Schistosoma japonicum , Esquistossomose/prevenção & controle , Caramujos/efeitos dos fármacos , Caramujos/parasitologia
6.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(2): 115-120, 2019 Apr 30.
Artigo em Chinês | MEDLINE | ID: mdl-31184039

RESUMO

OBJECTIVE: To evaluate the molluscicidal activity of a novel molluscicide pyriclobenzuron against Oncomelania hupensis robertsoni in the mountain regions of Yunan Province, and test its toxicity to fish, so as to provide scientific evidence for the extensive application of this molluscicide in schistosomiasis-endemic foci of Yunan Province. METHODS: In the laboratory and snail-breeding field of Dali Prefecture, Yunnan Province, the molluscicidal activity of 5% wettable powder of pyriclobenzuron sulphate (25% PBU) against O. hupensis robertsoni was assessed by using the immersion and spraying method, and the acute toxicity of 25% PBU to carp fries was tested, while 25% wettable powder of niclosamide ethanolamine salt (50% WPNES) served as a control. RESULTS: The 1-, 2- and 3-day 25% PBU LC50 and LC90 values were 0.47, 0.25 and 0.23 mg/L, and 1.54, 0.61 and 0.49 mg / L for O. h. robertsoni by using the immersion method in laboratory, and immersion with 25% PBU at 1.0 mg / L for 1 day achieved a comparable molluscicidal efficacy in relative to 50% WPNES at 1.0 mg/L. Spraying with 25% PBU at 4.0 g/m2 achieved 1-, 3- and 7-day snail mortalities of 64.23%, 96.67% and 100.00% in laboratory, respectively, which were not significantly different from those caused by treatment with 50% WPNES at 1.0 g/m2 (all P values > 0.05). One-day field immersion with 25% PBU at doses of 1, 2 and 4 g/m3 resulted in snail mortalities of 90.00%, 93.33% and 100.00%, respectively, which were not significantly different from those caused by treatment with 50% WPNES at 1.0 g/m3 (all P values > 0.05), and 3-day field spraying with 25% PBU at doses of 2.0 and 4.0 g/m2 caused snail mortalities of 86.36% and 87.72%, respectively, which were not significantly different from those caused by 50% WPNES treatment (both P values > 0.05). The 24-, 48- and 72-hour LC50 values of 25% PBU to carp fries were 29.38, 24.62 and 23.38 mg/L, respectively, and no fish death was observed within 72 hours of exposure to 25% PBU at a concentration of 17.5 mg/L and lower. CONCLUSIONS: 25% PBU is a novel, highly potent and environment-friendly molluscicide that is feasible in fish ponds, and the recommended dose is 1 g/m3 for field immersion and 2 g/m2 for field spraying in schistosomiasis-endemic areas of Yunnan Province.


Assuntos
Moluscocidas , Caramujos , Animais , China , Moluscocidas/toxicidade , Caramujos/efeitos dos fármacos
7.
Environ Sci Pollut Res Int ; 26(21): 21858-21870, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31134547

RESUMO

Over time, the consumption of pharmaceutical drugs has highly augmented, directly contributing for an increase of the discharges of these substances into sewage water due to excretion, and their direct release to the environment, with or without adequate treatment. Considering that part of the sewage water is dumped into rivers and seas, this is the major source of contamination of the aquatic environment. Paracetamol and acetylsalicylic acid are among the most worldwide consumed pharmaceutical drugs, frequently found in wastewater discharges and consequently in the aquatic environment in considerable amounts, posing ecotoxicity concerns especially towards aquatic non-target species. Thus, it is important to study the ecotoxicological implications that these drugs might pose to organisms from aquatic environments. The objective of this study was to assess the toxic effects of these two compounds on key biochemical features (antioxidant defenses and damage, metabolism, and cholinergic neurotoxicity) of the marine snail species Gibbula umbilicalis after an acute (96 h) exposure, simulating pulses of contamination. In order to understand the effects that those drugs have on this species, the biochemical biomarkers analyzed were the activities of catalase (CAT), glutathione-S-transferases (GSTs), cholinesterases (ChEs), and the levels of lipid peroxidation (TBARS). After acute exposure to paracetamol, catalase activity decreased significantly in organisms exposed to both highest concentrations; no significant alterations were observed for glutathione-S-transferases activity; TBARS concentration decreased significantly in organisms exposed to the intermediate and both highest concentrations, and cholinesterase activity increased significantly in animals exposed to the lowest concentration. However, after acute exposure to acetylsalicylic acid, catalase activity increased significantly; no significant alterations were observed for glutathione-S-transferases activity, and TBARS concentrations and cholinesterase activity increased. This set of data shows that G. umbilicalis is highly responsive to the presence of the tested drugs, and may thus be a promising species to serve as test organism in future marine ecotoxicological testing. The adoption of this species may broaden the offer of highly ecologically representative test organisms to be included in biomonitoring projects of the coastal and marine environment. Furthermore, it is possible to suggest that both drugs may pose significant deleterious effects of pro-oxidative origin to the physiology of the selected species, with potential adverse ecological consequences, even after short periods of exposure. The absence of neurotoxicity showed that despite being able to trigger antioxidant mechanisms, both drugs did not affect neurotransmission.


Assuntos
Acetaminofen/toxicidade , Aspirina/toxicidade , Caramujos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Organismos Aquáticos , Ecotoxicologia/métodos , Biomarcadores Ambientais/efeitos dos fármacos , Monitoramento Ambiental , Enzimas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Caramujos/metabolismo
8.
Infect Dis Poverty ; 8(1): 27, 2019 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-31014390

RESUMO

BACKGROUND: Control of snail intermediate hosts has been proved to be a fast and efficient approach for interrupting the transmission of schistosomiasis. Some plant extracts have shown obvious molluscicidal activity, and a new compound Luo-Wei, also named tea-seed distilled saponin (TDS), was developed based on the saponins extracted from Camellia oleifera seeds. We aimed to test the molluscicidal activity of 4% TDS against the intermediate host snails in China and Egypt, and evaluate its environmental safety to non-target organisms. METHODS: In the laboratory, Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus were exposed to 4% TDS, and the median lethal concentration (LC50) was estimated at 24, 48 and 72 h. In the field, snail mortalities were assessed 1, 2, 3 and 7 d post-immersion with 2.5 g/m3 4% TDS and 1, 3, 7 and 15 d post-spraying with 5 g/m2 4% TDS. In addition, the acute toxicity of 4% TDS to Japanese quail (Coturnix japonica), zebrafish (Brachydanio rerio) and freshwater shrimp (Macrobrachium nipponense) was assessed by estimations of LC50 or median lethal dose (LD50). RESULTS: In the laboratory, the LC50 values of 4% TDS for O. hupensis were 0.701, 0.371 and 0.33 mg/L at 24, 48 and 72 h, respectively, and 4% TDS showed a 1.975 mg/L [corrected] 24 h LC50 against B. alexandrina, and a 1.396 mg/L 24 h LC50 against B. truncatus. Across all study regions, the pooled mortalities of O. hupensis were 72, 86, 94 and 98% at 1, 2, 3 and 7 d, following field immersion of 4% TDS at a dose of 2.5 g/m3, and were 69, 77, 85 and 88% at 1, 3, 7 and 15 d, following field spraying at 5 g/m2, respectively. 4% TDS had moderate toxicity to Japanese quail (7 d LD50 > 60 mg/kg) and to shrimp (96 h LC50 = 6.28 mg/L; 95% CI: 3.53-11.2 mg/L), whereas its toxicity to zebrafish was high (96 h LC50 = 0.15 mg/L; 95% CI: 0.14-0.17 mg/L). CONCLUSIONS: 4% TDS is active against O. hupensis, B. alexandrina and B. truncatus under laboratory and field conditions, and it may be a candidate molluscicide of plant origin.


Assuntos
Moluscocidas/administração & dosagem , Moluscocidas/toxicidade , Schistosoma/efeitos dos fármacos , Caramujos/efeitos dos fármacos , Caramujos/parasitologia , Animais , Biomphalaria , Bulinus , China , Egito , Dose Letal Mediana , Extratos Vegetais , Codorniz , Esquistossomose/prevenção & controle , Testes de Toxicidade
9.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 30(6): 615-618, 2019 Jan 17.
Artigo em Chinês | MEDLINE | ID: mdl-30891970

RESUMO

OBJECTIVE: To evaluate the actual effect of the schistosomiasis control program in Jiangsu Province from 2010 to 2015. METHODS: A total of 67 schistosomiasis-endemic counties in 10 cities were selected, and a combination of retrospective investigation and on-site investigation was adopted to collect and record the epidemic data of the counties from 2010 to 2015, and a retrospective survey database of epidemic situation was established. The effects of integrated control strategies with both Oncomelania hupensis snail control and infection source control were evaluated. RESULTS: From 2010 to 2015, 2 465 911 persons who lived in endemic areas were detected for schistosomiasis, with 16 974 positive cases of blood examinations, and 8 positive cases of fecal examinations. Totally 5 145 people with advanced schistosomiasis were treated and 40 460 people with the history of schistosome cercarial-infested water contact received the expanded chemotherapy. A total of 127 636 cattle raised in the endemic areas were detected, and 51 619 cattle (head-times) with the history of cercarial-infested water contact also received the expanded chemotherapy. The area with snails control by molluscicides was 18 604.84 hm2. By the end of 2015, schistosomeinfected snails had not been found and there was no zoological schistosome infection for 5 consecutive years, and in addition, there had been no acute schistosome-infected persons for 6 consecutive years in the whole province. The area with snails dropped to 1 977.18 hm2, with a decreasing rate of 55.24% compared with that in 2010. CONCLUSIONS: After the implementation of the plan for the prevention and control of schistosomiasis in Jiangsu Province (2010-2015), the prevention and control of schistosomiasis has achieved remarkable effects and realized the goal of the plan.


Assuntos
Programas Governamentais , Moluscocidas , Esquistossomose , Animais , Bovinos , China , Programas Governamentais/normas , Moluscocidas/farmacologia , Estudos Retrospectivos , Schistosoma/fisiologia , Esquistossomose/prevenção & controle , Caramujos/efeitos dos fármacos , Caramujos/parasitologia
10.
Pest Manag Sci ; 75(10): 2770-2775, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30838743

RESUMO

BACKGROUND: Terrestrial mollusks are one of most important agricultural pests worldwide. Natural phytochemicals have an extended history as a source of pesticides. This study was planned to isolate molluscicidal active compounds from the stems of Adenium obesum. RESULTS: The benzene-soluble fraction of the hydroethanolic extract displayed the most potent molluscicidal activity against Monacha obstructa among different solvent fractions with a median lethal dose (LD50 ) of 4.91 µg g-1 body weight (bw). The bioactivity-guided chemical exploration of the benzene-soluble fraction led to the isolation of two known cardiac glycosides, cerberin and neriifolin which showed significant molluscicidal activity with LD50 values of 5.39 and 4.3 µg g-1 bw, respectively. CONCLUSION: Isolation of the cardiac glycoside neriifolin from A. obesum and the molluscicidal activity of cerberin and neriifolin against terrestrial snails are reported for the first time. © 2019 Society of Chemical Industry.


Assuntos
Apocynaceae/química , Cardenolídeos/farmacologia , Glicosídeos Cardíacos/farmacologia , Moluscocidas/farmacologia , Caramujos/efeitos dos fármacos , Animais , Dose Letal Mediana , Extratos Vegetais/farmacologia , Caules de Planta/química
11.
Environ Sci Pollut Res Int ; 26(14): 14184-14193, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30859440

RESUMO

Acrylamide (ACR) is a widespread industrial chemical with recognized adverse effects not only to humans but to other organisms in the environment as well. In the present study, the ecotoxicological effects of dietary exposure to sublethal concentration (1/20 LC50) of ACR on the land snail, Theba pisana after 2 weeks of exposure and 1-week recovery with respect to oxidative stress parameters; lipid peroxidation (LPO), reduced glutathione (GSH), catalase (CAT), and glutathione-S-transferase (GST), cytogenetic parameter; deoxyribonucleic acid (DNA) content, as well as immunological parameters; cell death, phagocytosis, lysosomal membrane stability (LMS), lectins, superoxide anion (O2-) generation, phenoloxidase (PO), peroxidase (POD), and hemocyanin (Hc) were examined. The results showed that ACR significantly increased LPO level and the activity of CAT and GST, cell death, and Hc level, whereas a significant decline in DNA and GSH contents, phagocytic activity, LMS, lectins, O2- generation, POD, and PO activities compared to the controls after 2-week exposure was observed. After 1-week recovery, most of the tested parameters in exposed snails were permanent and not reversible to the control levels. This study suggests that the tested multiple parameters of T. pisana species may be used as biomarkers of ACR exposure. Besides, T. pisana snails could be used as a good sentinel organism for ACR exposure in pollution monitoring studies.


Assuntos
Acrilamida/toxicidade , Poluentes Ambientais/toxicidade , Caramujos/fisiologia , Acrilamida/metabolismo , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Ecotoxicologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Dose Letal Mediana , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Caramujos/efeitos dos fármacos
12.
Parasitol Res ; 118(5): 1673-1677, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30850865

RESUMO

Swimmer's itch has historically been controlled by applying copper sulfate (CuSO4) to lakes as a way to eliminate snails that serve as the intermediate hosts for swimmer's itch-causing parasites. CuSO4 is still sometimes applied specifically to areas of lakes where swimmer's itch severity is high. It is unclear whether targeted application of chemical molluscicides like CuSO4 is effective for controlling swimmer's itch. Previous research has found that the larval stage of the parasites responsible for swimmer's itch are released from infected snails and are concentrated by onshore and alongshore winds, and thus, may not be affected by such focused applications. In this study, we evaluated the impact of targeted CuSO4 application to a specific recreational swimming area in a lake in Michigan. We measured the effect on snail populations, as well as on the presence/abundance of swimmer's itch-causing parasites using qPCR. Ultimately, while CuSO4 was confirmed to significantly reduce populations of snails within the treatment area, it was found to have no significant impact on swimmer's itch-causing parasites in the water, likely due to the free-swimming larval stages (cercariae) moving into the treatment area from surrounding regions.


Assuntos
Sulfato de Cobre/farmacologia , Dermatite/prevenção & controle , Dermatite/parasitologia , Dermatopatias Parasitárias/prevenção & controle , Caramujos/efeitos dos fármacos , Caramujos/parasitologia , Animais , Cercárias , Feminino , Humanos , Lagos/parasitologia , Larva/crescimento & desenvolvimento , Michigan , Reação em Cadeia da Polimerase em Tempo Real , Natação , Trematódeos/isolamento & purificação , Infecções por Trematódeos/prevenção & controle
13.
Artigo em Inglês | MEDLINE | ID: mdl-30880276

RESUMO

The objective of the present study was to evaluate the influence of the organophosphorus pesticide dimethoate and cadmium on biochemical parameters of a freshwater snail, Galba truncatula, in laboratory conditions. In 14 days, snails were exposed to 0, 100, 200, and 400 µg L-1 of dimethoate and 0.0 and 1000 µg L-1 of cadmium chloride. The results evidenced that dimethoate induces oxidative stress and alters biochemical parameters in freshwater snails. Cadmium also induced significant changes in biochemical parameters. The combination of the dimethoate and cadmium markedly increased the effects on G. truncatula. Dimethoate and cadmium mixture caused a decrease in Acetylcholinesterase (AChE), and Glucose-6-phosphate dehydrogenase (G6PDH) activities, glycogen, and total antioxidant capacity (TAN) levels, and increased aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), glutathione peroxidase (GPx), and catalase (CAT) activities, and malondialdehyde (MDA) level in exposed snails. The increased toxicity and bioaccumulation of cadmium after the exposure to the highest concentration of dimethoate indicates a synergistic effect leading to a reduced performance of the detoxification system in the snail. Dimethoate contributed to the bioconcentration of cadmium in snails and increased its toxic effects evidenced in biomarkers of oxidative stress and cell damage.


Assuntos
Cádmio/toxicidade , Dimetoato/toxicidade , Caramujos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Cádmio/administração & dosagem , Dimetoato/administração & dosagem , Glicogênio , Malondialdeído , Testes de Toxicidade
14.
Infect Dis Poverty ; 8(1): 13, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30732636

RESUMO

BACKGROUND: Snail control is an important component in the national schistosomiasis control programme in China, by application of chemical molluscicides, forestry projects, agriculture projects and water conservancy projects in recent decades. However, there are still wide areas of snail inhabited in China which remains a great challenge to achieve the goal of schistosomiasis elimination by 2025. Therefore, a SWOT (strengths, weaknesses, opportunities and threats) analysis on snail control measures is required for precision schistosomiasis control. METHODS: The SWOT approach, which is a well-known structured analysis tool, was used to identify and evaluate the specific characteristics of four types of snail control measures in China, including chemical mollusciciding, forestry, agriculture, and water conservancy projects. The analysis were carried out based on the information collection from literature review, of research papers, books, annual report database of national schistosomiasis control programme in China, reports from the academic forums, and so on. RESULTS: For chemical mollusciciding, application strategy needs to focus on specific local settings, such as stage of schistosomiasis control, environmental factors, and limitations from external policies and internal deficiencies. Regarding forestry projects, the optimal strategies are to cooperate with other national forestry programmes to share the investment costs and pay attention on wetland protection. In agriculture projects, it is necessary to develop related cash crop industries and combine with national farmland consolidation projects simultaneously to increase the total economic benefits. Concerning water conservancy projects, the main purpose is to control snail migration from snail area to snail-free areas nationwide. CONCLUSIONS: Integrated strategies for various measures application and a top-level designed cooperation mechanism will be the necessary to eliminate snail and schistosomiasis in China.


Assuntos
Modelos Biológicos , Moluscocidas/uso terapêutico , Controle de Pragas/métodos , Esquistossomose/prevenção & controle , Caramujos , Agricultura , Animais , China , Florestas , Humanos , Caramujos/efeitos dos fármacos , Caramujos/parasitologia
15.
Chemosphere ; 222: 56-61, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30690401

RESUMO

Schistosomiasis japonica caused by Schistosoma japonicum infection is recognized as a considerable economic and public health concern in Asia. Oncomelania hupensis is the sole intermediate host of S. japonicum. The only molluscicide recommended by World Health Organization (WHO) since 1960s is relative toxic to other aquatic species. In this article, we evaluated the novel molluscicide PPU07 in field trials on their efficiency against O. hupensis and toxicity for local fish. 25% PPU07 sulfate WP exhibited similar molluscicidal effect at 2.0 g/m2 and 2.0 g/m3 in the spraying and immersion trials with the WHO recommended molluscicide niclosamide (1 g/m2 and 1 g/m3). The mortality rates reached 95% and 96%, respectively. Moreover, little toxicity was observed for local fish and other aquatic organisms at the effective molluscicidal concentrations. In all, 25% PPU07 sulfate WP is a promising molluscicide for snail control, particularly in semi-commercial or commercial aquaculture ponds.


Assuntos
Peixes/fisiologia , Moluscocidas/toxicidade , Caramujos/efeitos dos fármacos , Animais , Ásia , Niclosamida/toxicidade , Schistosoma japonicum/efeitos dos fármacos , Análise de Sobrevida
16.
Chemosphere ; 221: 750-757, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30684772

RESUMO

The loading of La can substantially enhance the adsorption capability of drinking water treatment residue (DWTR) for better recycling. Normally, the modification was based on incubation of DWTR and La solution at a certain ratio, following by solid-liquid separation and drying processes. This study attempted to simplify La loading procedures by adopting high ratio of DWTR and La solution to eliminate the solid-liquid separation, aiming to promote the potential actual production. According to the results of the short- (2 d) and long-term (30 d) P adsorption tests, the N2 gas sorption and desorption analysis, the X-ray photoelectron spectroscopy analysis, and the metal fractionation, the substantial enhanced adsorption capability of the modified DWTR was maintained and the La loading mechanisms to DWTR changed little after eliminating solid-liquid separation processes during modification; typically, La loading increased the initial P adsorption rates from 1.00 (raw DWTR) to 6.08 and 6.03 mg g-1 d-1 for the modified DWTR with and without the separation processes. Furthermore, the DWTR before and after modification had little unfavorable effect on the survival of snail Bellamya aeruginosa, while eliminating the separation processes tended to reduce the bioavailability of Al, Fe, and La in the modified DWTR. These results demonstrated that solid-liquid separation was not the key step for DWTR modification and that the developed simple modification method was feasible for La loading to DWTR, promoting the beneficial recycling in environmental remediation.


Assuntos
Água Potável/análise , Recuperação e Remediação Ambiental/métodos , Lantânio/química , Purificação da Água/métodos , Adsorção , Animais , Disponibilidade Biológica , Lantânio/farmacocinética , Lantânio/farmacologia , Metais/farmacocinética , Reciclagem , Caramujos/efeitos dos fármacos
17.
Ecotoxicol Environ Saf ; 167: 242-249, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30342357

RESUMO

The ecotoxicological effects of dietary exposure to sublethal concentration (1/20 LC50) of abamectin (ABM) and thiamethoxam (TMX) for two weeks exposure and one week recovery on oxidative stress parameters; lipid peroxidation (LPO), reduced glutathione (GSH), catalase (CAT) and glutathione S-transferase (GST), Deoxyribonucleic acid (DNA) damage as well as immunological parameters; cell death, phagocytosis, lysosomal membrane stability (LMS), lectins, superoxide anion (O2-) generation, phenoloxidase (PO), peroxidase (POD) and hemocyanin (Hc) of the land snail, Theba pisana were examined. The results showed that both tested compounds significantly increased DNA damage, LPO content, the activity of CAT and GST, cell death, POD activity, Hc level, whereas, significantly declined in phagocytic activity, LMS, lectins level, O2- generation, PO activity, and GSH content compared to the controls after two week exposure. After one week of recovery, the measured biochemical parameters of treated snails were slightly repaired but their levels were still less than that of the level of untreated animals. Overall, based on acute toxicity endpoints, ABM appeared to be more harmful than TMX against this animal. Indeed, the different patterns of endpoint responses could represent a useful picture to characterise exposure to these pesticides in the land snail, T. pisana. This battery of snail endpoints might be a promising option to biomonitor the health of the terrestrial ecosystem and to offer valuable insights to the pesticides toxicity mechanisms.


Assuntos
Ivermectina/análogos & derivados , Praguicidas/toxicidade , Caramujos/efeitos dos fármacos , Tiametoxam/toxicidade , Animais , Catalase/metabolismo , Dano ao DNA/efeitos dos fármacos , Ecossistema , Ecotoxicologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Imunidade Celular/efeitos dos fármacos , Ivermectina/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo
18.
Artigo em Inglês | MEDLINE | ID: mdl-30528701

RESUMO

This work aimed to study in the freshwater gastropod Planorbarius corneus the effects of acute (2 days) and subchronic (14 days) exposures to an environmental concentration of the organophosphate azinphos-methyl on different reproductive parameters, offspring survival and B-esterase activities in gonads and in the whole organism soft tissue. The acute exposure inhibited only carboxylesterase activity in both tissues while the subchronic exposure also inhibited cholinesterase activity, decreased the number of hatched-eggs and increased offspring lethality (92%). On the other hand, B-esterases in gonads were more effective biomarkers than B-esterases in the whole organism due their inhibition appeared earlier in time (cholinesterase activity) and their activity remained inhibited for a longer time (carboxylesterase activity) when recovery studies were performed. We concluded that B-esterases and reproductive parameters can be used as effect biomarkers of aquatic contamination with azinphos-methyl. Our studies showed that a 14 days exposure to an environmental concentration of azinphos-methyl produced severe signs of toxicity in adult organisms, egg masses and juveniles that could cause negative effects at the population level in contaminated environments.


Assuntos
Azinfos-Metil/toxicidade , Inseticidas/toxicidade , Caramujos/efeitos dos fármacos , Animais , Azinfos-Metil/administração & dosagem , Bioensaio , Esquema de Medicação , Esterases/metabolismo , Inseticidas/administração & dosagem , Longevidade , Reprodução/efeitos dos fármacos , Caramujos/enzimologia , Caramujos/fisiologia
19.
Environ Toxicol Pharmacol ; 65: 9-13, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30468972

RESUMO

The available information on the interplay between low-dose cadmium intake and copper, manganese, and iron homeostasis in invertebrates is limited. We have currently studied the accumulation of these trace metals in the hepatopancreas of adult snails, Cantareus aspersus, following 14 and 28 days of exposure to low doses of dietary cadmium, up to 1 mg/kg dw (dry weight). The cadmium dose, but not the duration of exposure, had a significant effect on hepatopancreas copper deposition, the values being significantly elevated compared to controls. A significant peak in manganese levels at 14 days was found in snails administered the lowest cadmium dose. These increases occurred even in the absence of cadmium increase in the hepatopancreas. Our data suggest that low dose cadmium feeding can produce a transient disturbance in hepatopancreas copper and manganese homeostasis. Such responses may serve as early biomarkers of physiological changes occurring during the initial stages of cadmium intoxication.


Assuntos
Metais Pesados/metabolismo , Metais Pesados/toxicidade , Caramujos/efeitos dos fármacos , Animais , Dieta , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Homeostase/efeitos dos fármacos , Caramujos/metabolismo
20.
Physiol Plant ; 165(2): 209-218, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30144087

RESUMO

Metal defence against insect herbivory in hyperaccumulator plants is well documented. However, there are contradictory results regarding protection against snails. According to the joint effects hypothesis, inorganic and organic defences cooperate in plant protection. To test this hypothesis, we explored the relationships between snail (Cantareus aspersus) feeding and multiple inorganic and organic leaf components in the Cd hyperaccumulator plant Noccaea praecox. Plants grouped by rosette size growing in nutrient solution supplemented or not with 50 µM Cd were offered to the snails. After 3 days of snail feeding, the plants and snails were analysed. In addition to Cd concentrations, we analysed leaves for nutritional factors (sugar and protein), defence-related compounds (glucosinolates, phenolics, tannins, salicylic acid and jasmonate) and essential mineral nutrients. Cadmium concentrations in the snails and in snail excrements were also analysed. Snails preferentially fed on plants grown without Cd. Medium-sized plants exposed to Cd were the least consumed. Snail excrements from this trial weighed less and had higher Cd concentrations than those from other treatments. Cadmium increased salicylate and jasmonate production. A positive relationship between jasmonate levels and the number of attacked leaves was found. Principal component analysis revealed that leaf sugar concentration was the main factor positively affecting snails' leaf consumption, while leaf Cd had a negative but weaker influence. In conclusion, leaf sugar concentration mainly governs snails' feeding preferences. High leaf Cd concentrations do not deter herbivores from attacking leaves, but they do reduce leaf consumption. Our results clearly support the joint effects hypothesis.


Assuntos
Metais/toxicidade , Caramujos/fisiologia , Açúcares/metabolismo , Animais , Biomassa , Brassicaceae/metabolismo , Herbivoria/efeitos dos fármacos , Folhas de Planta/metabolismo , Análise de Componente Principal , Caramujos/efeitos dos fármacos
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