Atrazine, an herbicide is one the most toxic and sustaining pollutants in aquatic environment. It is detectable in surface water and in underground sources of drinking water. Many studies indicate that atrazine might be a potent endocrine-disrupting xenobiotic. There are limited studies have revealed that the effects of atrazine on sex steroids hormones, vitellogenin and induction of aromatase, gonadosomatic index and hepatosomatic index. In this study, juveniles Poecilia sphenops fish was exposed to three different (0.83ppm, 1.25ppm and 2.5ppm) concentration of atrazine for 100 days. Changes in plasma and gonadal content and concentrations of sex steroids and vitellogenin protein in poecilia sphenops under laboratory conditions were assessed. The low level of the Atrazine show estrogenic effect in males, as determined by a shortage of testosterone induction. Present study suggests that low induction of plasma vitellogenin and aromatase in male fish become suitable biomarkers of exposure to estrogenic chemicals.
Keywords: Poecilia sphenops, Atrazine, sex steroid disruption, vitellogenin and aromatase
Herbicides are extensively used in agriculture, sanitation, gardens and weed control. Terrestrial and aquatic environments are mainly polluted by indiscriminately used agriculture products [1]. They contaminate the food chains and display toxic effects in animals and the human population. In the last 60years, atrazine (2-chloro-4-ethylamino-6- isopropylamino-s-triazine) has been one of the most extensively used herbicides in agriculture and roadways, which has been considered as an endocrine disruptor, causing adverse effects on reproductive function mainly by altered sex hormone levels and gonadal abnormalities [2-6]. Possible intera...
... middle of paper ...
...ner [11]. Mature male Atlantic salmon are affected by atrazine with a significant reduction of 11-KT. male sex steroid metabolism seems to be disrupted by atrazine exposure [23]. However, only limited information is available on the effect of atrazine on VTG production, aromatase activity and sex hormone levels in fish. Hence, fish can be used as experimental models in studies of endocrine disruption effects and also can serve as an early-warning signal. Therefore, the objectives of this study were to elucidate the effects of atrazine on plasma and gonadal hormones, Gonadosomatic index and hepatosomatic index in Poecilia sphenops. Further the present study probe on sensitive markers like vitellogenin and aromatase in fish Poecilia sphenops. The information obtained may be useful to explore the potential biomarkers for atrazine biomonitoring in aquatic environments.
To begin the lab, the variable treatment was prepared as the Loggerlite probe, used to later measure oxygen consumption, warmed up for approximately 10 minutes. To prepare the variable treatment, 200ml of Sodium and Ammo-lock water was measured in a container and a pre-prepared “tea bag” of tobacco was steeped in the room temperature treated water until a light yellow color was visible. After preparing the tobacco solution the preparation for the live goldfish began as two beakers were filled with 100 ml of treated water. Each beaker was weighed before addi...
The purpose of this lab was to study the response of the genus Daphnia to chemical stimuli and to examine human responses to different stimuli. A stimulus is an incentive; it is the cause of a physical response. Stimuli can have a physical or chemical change; an example of a physical change is a change in temperature and sound. An example of chemical change would be changes in hormone levels and pH levels. Muscular activity or glandular secretions are responses that occurs when stimulus information effects the nervous and/or hormone system. Daphnia is a genus; it is a small crustacean that lives in fresh water. The body of the daphnia is visible and its internal organs are clearly seen thus it was chosen for this exercise. The
The pesticide DDT banned in 1987 was a detrimental to the environment leading to it to be banned in 1987. DDT remains in the soils for a long period of time. The chemicals affect the ecology of the soil and water run off causing contamination of livestock and native animals and aquatic species. Studies indicated a range of human health impacts from DDT including cancers, infertility, miscarriage and nervous system impairment. The social and economic impact of DDT use in viticulture was significant.
There are many issues regarding the raising and producing of various livestock animals, and the use of pesticides on various types of crops. The movie Food.Inc does a good job explaining these issues, but in a very biased way. It makes agriculturists look like terrible people, when this is not the case.
In the early development process of many organisms, it is important to be able to minimize exposure to agents of stunted or arrested development. By decreasing the mortality rate for a generation of a species, that species is given an advantage in later reproduction; by increasing the number of organisms of the same species within a limited environment, more organisms of the same species are able to reproduce, resulting in an augmented overall population ("Reproduction and Development", 2013). However, when toxins are introduced to an environment, an embryo’s viability can decrease. Mortality rates for the generation of the species can increase, and defects that are harmful to the reproductive cycle can emerge. Thus, it is necessary to measure and observe the effects of certain toxins on embryonic development. The North American brine shrimp, or Artemia Franciscana (Artemia Salina), is subject to changes in its environment. Toxins introduced to its hatching environment, such as ethanol (in concentrations of 0.1%, 0.15%, and 0.2%), can have significant impact for the hatching process and embryonic development. The experiment sought to explore the relationship between birth defects and exposure to ethanol at early developmental stages through the use of American brine shrimp. However, to be able to fully comprehend the impact that certain toxins would have on the embryonic development of the North American brine shrimp, it is first important to be versed in its specific hatching process.
In a study conducted by Louis J. Guillette Jr. of the University of Florida and Ana M. Soto of Tufts University School of Medicine in Boston, hormonal activity of water from sites located both upstream and downstream of feedlots in Nebraska were tested by adding the water samples to cells that “react in various ways to hormonal steroids” (Raloff, 2002, para 17-18). The study (as cited in Raloff) found that:
Ross, P. R., Jeffries, S. J., Yunker, M. B., Ikonomou, M. G., & Calambokidis, J. C. (2004). Harbor seals (Phoca vitulina) in British Columbia, Canada, and Washington State, USA, reveal a combination of local and global polychlorinated biphenyl, dioxin, and furan signals. Environmental Toxicology and Chemistry, 23(1), 157-165. Retrieved from http://onlinelibrary.wiley.com/doi/10.1897/03-85/abstract?deniedAccessCustomisedMessage=&userIsAuthenticated=false
Chemical pollution into the environment can cause both genotypic and phenotypic changes in many organisms, including humans. More specifically, environmental pollutants like BPA can act as xenoestrogens (estrogen imitators), ultimately affecting hormonal activity and production in an organism. This alteration in activity and production can be termed as endocrine disruption. The endocrine system regulates a variety of processes responsible for growth and development, including gonadal formation and function, digestion, metabolism, sex differentiation, and embryonic development (reviewed by Flint et al., 2012). Chemicals that interfere with the function or structure of the endocrine system can be defined as endocrine disrupting compounds (EDCs) (US Environmental Protection Agency, 2007).
U.S. Food And Drug Administration (2013, July 23). An overview of Atlantic salmon, its natural history, aquaculture, and genetic engineering. Retrieved May 1, 2014, from http://www.fda.gov/AdvisoryCommittees/CommitteesMeetingMaterials/VeterinaryMedicineAdvisoryCommittee/ucm222635.htm
middle of paper ... ... sk for cancer. There is no need to be alarmed with high levels of contaminants when it comes to consuming any kind of salmon. What we do need to be alarmed about is the media reporting and their level of contaminants! 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.
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.
To help keep crops from being destroyed, conventional farmers use many methods such as pesticides, herbicides, and fungicides. Nearly 1 billion pounds of these chemicals are used every year (“pesticides”). Because of this excessive use, some scientists express concern that using artificial chemicals in the farming process could produce unhealthy crops. People who ate it over a long period of time could suffer from degraded health and stunted growth (“Organic Foods”). For example, in 1989, the EPA banned the use of Alar which was a chemical used to ripen apples (“Farming, Organics”). This chemical proved to be carcinogenic after causing tumors in mice after several laboratory tests (“Organic Food”). As a result of these findings there was a dramatic increase of the sales for organic food (“Organic Food”). Another study found that Atrazine (one of the most widely used herbicides in the United States) has the potential of being carcinogenic and reducing sperm counts in males (“Organic Food”). This was further proven when evidence was found that chemicals u...
Schramm, 2011). Another article had study on morphological development and characterization of aromatase and estrogen receptors alpha and beta in fetal ovaries of cattle. In this study the aim was to understand the role of estradiol-17β in fetal ovarian development, presence an localization of cytochrome p450 aromates (P450arom) and estrogen receptors alpha and beta proteins characterized in fetal ovaries of cattle. In the day of 110 of the experiment ovarian structures within different lobes appeared to be different morphological development stages. At the end of this experiment morphological development had analyzed that in granulosa cell growing of oocytes of follicles. Also both ERα and ERβ protein was observed in overigerous cords and granulosa cells and oocytes of follicles. (Burkart, 2009) Similar research had done by Celine Ferre, was “comparison of early morphological and molecular changes induced by 17-alpha-methytestosterone and estradiol benzoate in rat ovary.”(Ferre, 2013) The goal of this experiment was to identify early events and linked to morphological change in the ovary by exposure t...
An example of an additive is di-butyl phthalate and biphenyl A (BPA), these substances are incorporated while the plastics are being manufactured to provide tensile flexibility and tensile strength. The microplastics tend to accumulate and adsorb toxic materials from the seawater around them, such as organic pollutants and heavy metals. The chemicals are not bound to the microplastic surface, and as a result, when ingested they tend to leach into the animal tissues (Do Sul, J. A. I, 2014). The impacts from such chemical leaches include hepatic stress in fish, mortality, and endocrine
Nitrification leads to the production of nitrite and nitrate from the oxidation of ammonia. Ammonia and nitrite are inherently toxic to fish; however, the sensitivity to these nitrogenous compounds varies by species. It was suggested that in Cyprinus carpio, or common catfish, ammonia is regulated at the gill interface by Na+/K+-ATPase. With nitrite, fish are most sensitive in the early stages of growth; this is most often observed as poor gill structure and inflammation of muscle tissue (Kroupova et al., 2010). In a separate review, Dolomatov, et al., 2011, concluded that the most critical times for nitrite regulation are during the incubation of eggs; larvae rearing; and wintering fish.