scholarly journals Effects of Chlorpyrifos Ethyl on Cholinesterase and Growth of Silver Barb (Barbonymus gonionotus)

Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2885
Author(s):  
Nguyen Van Cong ◽  
Dinh Thai Danh ◽  
Tran Sy Nam
Keyword(s):  
Pesticide Exposure ◽  
Mekong Delta ◽  
Lethal Concentration ◽  
Effect Concentration ◽  
Risk Of Exposure ◽  
Rice Fish ◽  
Chlorpyrifos Ethyl ◽  
The Brain ◽  
Silver Barb ◽  
Local Farmers

Chlorpyrifos ethyl is a popular insecticide widely used in agriculture within the Vietnamese Mekong delta, including for rice farming. Here, local farmers often apply pesticides at very high rates which leads to contamination of the surrounding environment. Silver barb (Barbonymus gonionotus) is a fish species indigenous to the delta, which resides in a variety of water bodies and is also commonly cultivated in rice–fish systems. As a result, this species is at high risk of exposure to chlorpyrifos ethyl. This study aims to determine the lethal concentration (LC50) of chlorpyrifos ethyl, as well as the effects of sub-lethal concentrations on the activity of cholinesterase and growth of Silver barb. Lethal concentration testing was conducted in a static non-renewed system. Three concentrations of chlorpyrifos ethyl (1%, 10% and 20% LC50-96 h) were conducted in triplicate to assess the effects of chlorpyrifos ethyl on the brain cholinesterase (ChE) of fingerling fish for 15 days, and on their growth for 60 days. Results showed that chlorpyrifos ethyl was highly toxic to fingerling Silver barb with a LC50-96 h of 0.119 ppm. The lowest observed effect concentration (LOEC) was 1%LC50-96 h for ChE and 10%LC50-96 h for growth. No observed effect concentration (NOEC) of chlorpyrifos ethyl for growth was 1%LC50-96 h. The result from this study suggests that ChE activity is significantly inhibited at environmentally realistic concentrations in the Vietnamese Mekong delta and can be used as a biomarker of pesticide exposure. Further study in the rice fields as well as in the canals or rivers is required.

Factors affecting farmers’ adoption of integrated rice-fish farming systems in the Mekong delta, Vietnam

2012 ◽  
Vol 4 (3) ◽  
pp. 178-190 ◽  
Author(s):  
Roel H. Bosma ◽  
Dang K. Nhan ◽  
Henk M. J. Udo ◽  
Uzay Kaymak
Keyword(s):  
Mekong Delta ◽  
Farming Systems ◽  
Fish Farming ◽  
Factors Affecting ◽  
Rice Fish

scholarly journals Neurodegeneration in zebrafish embryos and adults after cadmium exposure

2017 ◽  
Vol 61 (4) ◽  
Author(s):  
Antonio Monaco ◽  
Teresa Capriello ◽  
Maria C. Grimaldi ◽  
Valentina Schiano ◽  
Ida Ferrandino
Keyword(s):  
Cell Death ◽  
Acridine Orange ◽  
Time Dependent ◽  
Lethal Concentration ◽  
Zebrafish Embryos ◽  
Adult Zebrafish ◽  
Essential Metal ◽  
Fluoro Jade B ◽  
Whole Mount ◽  
The Brain

<p>Cadmium is a biologically non-essential metal. It is also toxic to many organs including the brain. The aim of this study was to analyse the neurodegenerative effects of this metal in embryos and adults of zebrafish exposed to sub-lethal concentrations of cadmium. The study was performed by cytochemical stainings. Six hours after fertilisation (hpf) zebrafish embryos were treated for 24 hours with 9 μM of cadmium and subsequently stained with Acridine orange in whole mount to detect apoptosis in the brain. Adult zebrafish were treated for 16 days with the same concentration of cadmium, and cell death in the brain was detected by Fluoro-Jade B staining at 2, 7 and 16 days of treatment. An increase in cell death was observed only at 16 days of treatment in adults, while an increase in apoptotic events was revealed in the brain of embryos after 24 h of treatment. This evidence is indicative that cadmium, even at a sub-lethal concentration, induces cell death in the brain of embryos but also in adults of zebrafish in which the phenomenon appears time-dependent. </p>

Pesticides in the Homes of Farmworkers

2006 ◽  
Vol 34 (2) ◽  
pp. 335-353 ◽  
Author(s):  
Pamela Rao ◽  
Sara A. Quandt ◽  
Alicia M. Doran ◽  
Beverly M. Snively ◽  
Thomas A. Arcury
Keyword(s):  
Pesticide Exposure ◽  
Policy Recommendations ◽  
Scientific Debate ◽  
Perceptions Of Risk ◽  
Latino Women ◽  
Course Of Action ◽  
Risk Of Exposure ◽  
Low Levels ◽  
And Behavior ◽  
Depth Interviews

Pesticide exposure has been linked with immediate and delayed health effects. Anyone who lives in a farmworker household may be exposed to pesticides. Studies with farmworkers have found generally low levels of awareness of pesticide exposure and prevention. Less is known about the perceptions of nonfarmworkers living with farmworkers. This article presents the results of 41 in-depth interviews conducted with Latino women in farmworker households regarding their knowledge of pesticides and perceptions of risk to their children's health. Their perceptions and behavior differ from scientific understanding and policy recommendations for exposure management, resulting in behaviors that may increase children's risk of exposure and subsequent health problems. Because the level at which exposure becomes harmful remains a subject of scientific debate, the wisest course of action is to minimize exposure (the precautionary principle). Families living in farmworker households would benefit from health education programs that target their specific needs.

Estimating Exposure to Three Commonly Used, Potentially Carcinogenic Pesticides (Chlorolathonil, 2,4-D, and Glyphosate) Among Agricultural Workers in Canada

2020 ◽  
Author(s):  
Cheryl E Rydz ◽  
Kristian Larsen ◽  
Cheryl E Peters
Keyword(s):  
At Risk ◽  
Occupational Exposure ◽  
Crop Production ◽  
Pesticide Exposure ◽  
Agricultural Workers ◽  
Agricultural Industry ◽  
Adverse Health Outcomes ◽  
Farm Type ◽  
Risk Of Exposure ◽  
2,4 Dichlorophenoxyacetic Acid

Abstract Objectives Certain pesticides have been associated with adverse health outcomes including cancer and reproductive harms. However, little is known about the prevalence of occupational pesticide exposure among agricultural workers in Canada. The purpose of this study was to estimate the prevalence and likelihood of occupational exposure to pesticides in Canada’s agricultural industry, using three commonly used, potentially carcinogenic pesticides [chlorothalonil, 2,4-dichlorophenoxyacetic acid (2,4-D), and glyphosate] as an example. Methods Estimates were calculated using the Canadian Census of Population and the Census of Agriculture. The number of workers and the proportion of farms applying ‘herbicides’ or ‘fungicides’ by farm type was estimated using survey data from the Census of Agriculture. These values were multiplied to yield the potential number of workers at risk of exposure. Likelihood of exposure (i.e. exposed, probably exposed, and possibly exposed) was then qualitatively assigned using information on crop type, primary expected tasks, crop production practices, and residue transfer data. Additional agricultural workers who are at risk of exposure but not captured by the Census of Agriculture were identified using the 2016 Census of Population. Results An estimated range of 37 700–55 800 workers (11–13% of agricultural workers) were exposed to glyphosate in Canada while 30 800–43 600 workers (9–11%) and 9000–14 100 (2.9–3.2%) were exposed to 2,4-D and chlorothalonil, respectively. Approximately 70–75% of workers at risk of exposure were considered probably or possibly exposed to any of the pesticides. Glyphosate exposure was most common among workers in oilseed (29% of oilseed farm workers exposed) and dry pea/bean farms (28%), along with those providing support activities for farms (31%). 2,4-D exposure was most common in corn (28%), other grain (28%), and soybean farms (27%), while chlorothalonil exposure was more likely among greenhouse, nursery, and floriculture workers (42%), workers on farms (28%, for occupations not captured by the Census of Agriculture, specifically), and those providing support activities for farms (20%). Regional variations broadly reflected differences in farm types by province. Conclusions This study estimated the prevalence of occupational exposure to three pesticides in Canada. Seasonal and temporary agricultural workers, which were captured by the Census of Agriculture, contributed to many additionally exposed workers. A large percent of the workers who were considered at risk of exposure were considered probably or possibly exposed, indicating a need for enhanced data collection and availability on pesticide use data in Canada. The study’s methods can be applied to estimate workers’ exposures to other pesticides within the agricultural industry.

scholarly journals Neonicotinoid exposure affects foraging, nesting, and reproductive success of ground-nesting solitary bees

2020 ◽  
Author(s):  
D. Susan Willis Chan ◽  
Nigel E. Raine
Keyword(s):  
Reproductive Success ◽  
Food Production ◽  
Pesticide Exposure ◽  
Sublethal Effects ◽  
Environmental Stressors ◽  
Crop Pollination ◽  
Pollination Services ◽  
Risk Of Exposure ◽  
First Time ◽  
Ground Nesting

Despite their indispensable role in food production1,2, insect pollinators are threatened by multiple environmental stressors, including pesticide exposure2-4. Although honeybees are important, most pollinating insect species are wild, solitary, ground-nesting bees1,4-6 that are inadequately represented by honeybee-centric regulatory pesticide risk assessment frameworks7,8. Here, for the first time, we evaluate the effects of realistic exposure to systemic insecticides (imidacloprid, thiamethoxam or chlorantraniliprole) on a ground-nesting bee species in a semi-field experiment. Hoary squash bees (Eucera (Peponapis) pruinosa) provide essential pollination services to North American pumpkin and squash crops9-14 and commonly nest within cropping areas10, placing them at risk of exposure to pesticides in soil8,10, nectar and pollen15,16. Hoary squash bees exposed to an imidacloprid-treated crop initiated 85% fewer nests, left 84% more pollen unharvested, and produced 89% fewer offspring than untreated controls. We found no measurable impact on squash bees from exposure to thiamethoxam- or chlorantraniliprole-treated crops. Our results demonstrate important sublethal effects of field-realistic exposure to a soil-applied neonicotinoid (imidacloprid) on the behaviour and reproductive success of a ground-nesting solitary bee. To prevent potential declines in ground-nesting bee populations and associated impoverishment of crop pollination services, soil must be considered a possible route of pesticide exposure for bees, and restrictions on soil-applied insecticides may be justified.

scholarly journals Intranasal Glyphosate-Based Herbicide Administration Alters the Redox Balance and the Cholinergic System in the Mouse Brain

2019 ◽  
Author(s):  
Cristina Eugenia Gallegos ◽  
Mariana Bartos ◽  
Fernanda Gumilar ◽  
Rita Raisman-Vozari ◽  
Alejandra Minetti ◽  
...  
Keyword(s):  
Pesticide Exposure ◽  
Cholinergic Neurons ◽  
Redox Balance ◽  
Medial Septum ◽  
Brain Areas ◽  
Anterior Olfactory Nucleus ◽  
Psychomotor Disorders ◽  
Thiol Content ◽  
Glutamatergic Pathways ◽  
The Brain

ABSTRACTPesticide exposure is associated with cognitive and psychomotor disorders. Glyphosate-based herbicides (GlyBH) are among the most used agrochemicals, and inhalation of GlyBH sprays may arise from frequent aerial pulverizations. Previously, we described that intranasal (IN) administration of GlyBH in mice decreases locomotor activity, increases anxiety, and impairs recognition memory. Then, the aim of the present study was to investigate the mechanisms involved in GlyBH neurotoxicity after IN administration. Adult male CF-1 mice were exposed to GlyBH IN administration (equivalent to 50 mg/kg/day of Gly acid, 3 days a week, during 4 weeks). Total thiol content and the activity of the enzymes catalase, acetylcholinesterase and transaminases were evaluated in different brain areas. In addition, markers of the cholinergic and the nigrostriatal pathways, as well as of astrocytes were evaluated by fluorescence microscopy in coronal brain sections. The brain areas chosen for analysis were those seen to be affected in our previous study. GlyBH IN administration impaired the redox balance of the brain and modified the activities of enzymes involved in cholinergic and glutamatergic pathways. Moreover, GlyBH treatment decreased the number of cholinergic neurons in the medial septum as well as the expression of the α7-acetylcholine receptor in the hippocampus. Also, the number of astrocytes increased in the anterior olfactory nucleus of the exposed mice. Taken together, these disturbances may contribute to the neurobehavioural impairments reported previously by us after IN GlyBH administration in mice.

Experiment on an integrated rice-fish polyculture system.

2020 ◽  
Author(s):  
Nhut Salem
Keyword(s):  
Common Carp ◽  
Cost Benefit ◽  
Total Body Weight ◽  
Market Prices ◽  
Fish Yield ◽  
Cost Benefit Ratio ◽  
Rice Fish ◽  
Supplementary Feed ◽  
The Cost ◽  
Silver Barb

Abstract An experiment was carried out in Vietnam on an integrated rice-fish polyculture system with three species: common carp (Cyprinus carpio), Nile tilapia (Oreochromis niloticus) and silver barb (Barbonymus gonionotus). Agricultural by-products were used as supplementary feed at a rate of 2-3% total body weight of fish per day. The total fish yield (823 kg ha-1) and fish production (988 kg ha-1 yr-1) at 2 fish m-2 were significantly higher (p<0.05) than at 1 fish m-2 (453 kg ha-1 and 544 kg ha-1 yr-1, respectively). The cost : benefit ratio (1.80) and the cost : profit ratio (1.75) for farm household income at 1 fish m-2 were lower than at 2 fish m-2 (2.08 and 2.02, respectively). This system should be adopted by aquaculture extension programmes to improve rural farmers' income when the market prices for common carp, tilapia and silver barb are sufficiently high to obtain a benefit at the end of the culture cycle.

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