Imidazolinone herbicides are extensively used in recent years to control the growth of weeds in rice field area and improve its productivity. The herbicide used in the rice field is the combination of imazapyr (17.5%) and imazapic (52.5%) from the imidazolinone family plus inert ingredient (30%). Its persistence in soil media may pose severe ecological and human impacts through drifting or leaching. Since dietary intake is the main route for human exposure, fish can be the main contributor to the herbicide intake in human beings. Several studies have demonstrated a clear correlation between the frequency of fish consumption and the level of contaminant in human tissues, serum and milk.
In general, the determination of these herbicides in fish involves extraction of the analytes, removal of co-extracted lipids, concentration and chromatographic analysis. The most crucial steps are the extraction of target analytes from the bulk of the matrix and clean-up of the analytes from the matrix co-extractives. To date several extraction techniques have been applied such as liquid-liquid extraction (LLE), solid-liquid extraction (SLE), Soxhlet extraction (SE), matrix solid-phase dispersion (MSPD), microwave assisted extraction (MAE), ultrasonic assisted extraction, pressurized liquid extraction (PLE), supercritical fluid extraction (SFE) and accelerated solvent extraction (ASE).
Another extraction method of interest is solid phase extraction (SPE) techniques which is capable of extracting the polar compounds like the imidazolinone herbicide. SPE technique have been proven successful to determine imazapyr, imazathapyr, imazaquin, imazamox in water and soil media only. However, to our knowledge, no extraction method has been fully developed...
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...erbicides. Retrieved December 7, 2012, from http://www.epa.gov/caddis/ssr_herb_int.html
Ulbrich, A. V., J. R. P. Souza, et al. (2009). "Persistence and Carryover Effect of Imazapic and Imazapyr in Brazilian Cropping Systems1."
Wang, D., Yu, W., et al. (2013). “ Organochlorine pesticides in fish from Taihu Lake, China, and associated human health risk assessment.” .” Ecotoxicology and Environmental Safety 98: 383-389
Wu, C-X., Wang, J-J., et al. (2011). “Adsorption and Desorption of Methiopyrsulfuron in Soils.” Pedosphere 21(3):380-388
Wu, C., Zhang, S., et al. (2011). “Adsorption and desorption herbicide monosulfuron-ester in Chinese soils.” Journal of Environmental Sciences 23(9): 1524-1532
Yania, D., and Elsharkawy, E. E. (2014). “Multi pesticide and PCB residues in Nile tilapia and catfish in Assiut city, Egypt.” Science of the Total Environment 466-467: 306-314
The objective of this experiment was to perform extraction. This is a separation and purification technique, based on different solubility of compounds in immiscible solvent mixtures. Extraction is conducted by shaking the solution with the solvent, until two layers are formed. One layer can then be separated from the other. If the separation does not happen in one try, multiple attempts may be needed.
Añasco, N., Uno, S., Koyama, J., Matsuoka, T., Kuwahara, N. (2010): Assessment of pesticide residues in freshwater areas affected by rice paddy effluents in Southern Japan.
Pesticides in ground watrer seems to be a continual problem with people now days, because they think that the pesticides dont soak into the ground water. They believe that when a pesticide is sprayed on a plant the leaves are what pick up the pesticide but thats false, the roots pick up the pesticides which proves that the pesticides have to soak at least a few feet into the ground.
Ronad A. Hites, Jeffery A. Foran, David O. Carpenter, M. Coreen Hamilton, Barbara A. Knuth, Steven J. Schwager (2004) study: Global assessment of organic contaminants in farmed salmon, Science 303:226-229.
They are classified by many different factors. Included are target organisms, which are herbicides, fungicides, and insecticides. Another is their chemical structure, organic, inor...
Söffker M, Tyler CR (2012) Endocrine disrupting chemicals and sexual behaviors in fish – a critical review on effects and possible consequences. Critical Reviews in Toxicology 42(8), 653-668
The effects of temperature on the distribution of organic contaminants between different phases in the subsurface soil was demonstrated by Davis 1997. Calculations were carried out using the data of Heron et al. (1996) for tri-chloro ethane (TCE) at 90°C. The results indicated that raising the temperature to 90°C caused significant increase in the concentration of contaminant in the air phase under both high and low soil organic matter conditions and significantly decreased the amount that is associated with the solids. Only small amounts remain in the liquid phase. The researchers concluded that if the high organic matter content soil is under water saturated conditions, the amount of TCE in the water would approximately double as the temperature increased from 20°C to 90°C, but 82 percent of the TCE would remain adsorbed to the solids. Under low organic matter and water saturated conditions, there would be approximately a 30 percent increase in the amount of TCE in the water phase with an increase in temperature from 20°C to 90°C, leaving approximately 25 percent
Evidence provided to support these claims of human and wildlife harm is largely from laboratory studies in which large doses are fed to test animals, usually rats or mice, and field studies of wildlife species that have been exposed to the chemicals mentioned above. In laboratory studies, high doses are required to give weak hormone activity. These doses are not likely to be encountered in the environment. However the process of bioaccumulation can result in top-level predators such as humans to have contaminants at levels many million times greater than the environmental background levels (Guilette 1994). In field studies, toxicity caused by endocrine disruption has been associated with the presence of certain pollutants. Findings from such studies include: reproductive disruption in starfish due to PCBs, bird eggshell thinning due to DDT, reproductive failure in mink, small penises in alligators due to DDT and dicofol (Guillette 1994, Colburn et al 1996). In addition, a variety of reproductive problems in many other species are claimed to be associated with environmental contamination although the specific causative agents have not been determined. One recent discovery that complicates the situation is that there are many naturally occurring "phytoestrogens", or chemicals of plant origin that exhibit weak estrogenic properties.
Pesticides and Fertilizer run off from farms causes an overwhelming negative effects on the environment. Pesticides contaminate the water and poison fish both killing them and causing biological magnification in the fish that are higher up in the food chain. When humans eat these fish the risk of being harmed by pesticides is increased. Tobacco plants were engineered to express a gene that detoxifies 2,4-dichlorophenoxyacetate ( 2,4-D), one of the most commonly used pesticides world wide, and removes it from the soil.
The BaP concentrations and exposure regime were adapted with modification from a previous study finding multigenerational effects of benzo(a)pyrene exposure in zebrafish (Corrales et al. 2014b). To prepare the spiked diet, 36 g of decapuslated brine shrimp eggs were spiked with 27 mL of acetone containing BaP (0, 0.01667, 0.1667, or 1.667 μg/L). The spiked diets were air dried and stored in amber jars at room temperature. F0 females were housed at a density of 5 fish per 9.4 L aquarium (Pacific Coast Distributing, Inc., Phoenix, AZ, USA) with hanging filters, with three replicate tanks per treatment group. Water quality and photoperiod were maintained as above. Fish were allowed to acclimate for a week while being transitioned to a diet of untreated decapsulated brine shrimp eggs. The first day of the acclimation period and the day
Pesticides and herbicides are toxins that are used to kill of unwanted animals and plants. These may be collected by rainwater runoff and carried into steams, rivers, lakes, and e...
Presently, Monsanto is commonly known for its potent herbicide named Roundup. As the biggest-selling weed killer in the world, Roundup accounts for 17 percent of Monsanto’s total annual sales of $9 billion (Arax, 1997). The main ingredient of Roundup is glyphosate. Glyphosate is the eighth most commonly used herbicide in U.S. agriculture and the second most commonly used herbicide in nonagricultural settings (Cox, 1995). It’s estimated annual use according to the U.S. EPA is between 15 and 20 million pounds in agriculture and between 4 and 6 million pounds elsewhere (Arax, 1997). Monsanto claims that Roundup breaks down quickly in the soil, so that little or no toxic byproduct accumulates in plant or animal tissue - a viewpoint often disputed.
There are many pathways available by which pharmaceutical waste can find its way into our river, lakes, and groundwater. It has also become a growing concern because it harms the environment as a whole along with its various ecosystems. However, researchers have tried to find methods that can be implemented to eliminate this growing issue, and more tests have been done through the years to ensure a positive result in the water quality. Many scientists and researchers have been testing samples of water in rivers, surface water and wastewater plants all across the world to ensure that the pharmaceutical waste present in the water does not rise to a level at which it becomes extremely hazardous to the aquatic environment, agricultural livestock and ourselves.
There are 2.5 billion pounds of pesticides being applied to agricultural products each year in the United States. This is ten times more than was applied forty years ago. It is still unknown as to what type of exact effects these chemicals may have on individuals. Some farmers that have been using pesticides in their fields and developed leukemia are finding that the cause of their disease is from inhaling pesticides. These chemicals are still in use today and most of them have never been tested for the short or long-term effects that they may have on humans.
Pesticide is a chemical used to prevent, wipe out and control the pest problem in agriculture. The use of pesticides have become a common practice around the world, and used almost everywhere, such as agricultural fields, homes, park and school, and so on. Most pesticides are insecticides, herbicides and fungicides that have distinct purposes. Insecticides are used to control insects; herbicides are used to destroy plants; fungicides are used to prevent molds and mildews. Most commonly pesticides contain highly toxic chemical such as Acid copper chromate (ACC), Acephate and Chlorpyrifos, and so on. One of example of insecticides, Chlorpyrifos, sprays widely on a variety of food and golf courses in order to control pests in a cornfield. However, “Chlorpyrifos can cause cholinesterase inhibition in humans; that is, it can over stimulate the nervous system causing nausea, dizziness, confusion, and at very high exposures (e.g., accidents or major spills), respiratory paralysis and death.” (EPA GOV) In the market has thousands of products are similar as Chlorpyrifos.