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).
Humans are among the many terrestrial mammals affected by the endocrine-disrupting capabilities of bisphenol A. The majority of human exposure comes from consumption of BPA from food products packaged in polycarbonate plastics (Crain et al., 2007). Laboratory studies done on mice indicate that exposure to high concentrations of BPA can cause pregnancy complications, reproductive organ defects, obesity, early puberty, and cancer (reviewed by Flint et al., 2012).
Sex reversal has been observed in reptile species that rely on temperature-dependent sex determination when exposed to high levels of BPA. An example of this can be seen in a study done by Stoker et al. (2003). Researchers found that eggs treated with 90ugBPA/egg produced females when incubated at the male-specific temperature (reviewed by Flint et al., 2012).
BPA pollution into aquatic environments occurs through two main routes: (1) direct dumping of BPA-containing plastics, and (2) efflue...
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...et al. (2011). Using fluorescent imaging, the researchers found evidence of abnormal vascularization, neuron branching, and neuromast cell development in zebrafish (Danio rerio) exposed to the known endocrine disruptor during early life stages. Aluru et al. (2010) determined that maternal exposure to BPA can cause multiple adverse effects on developing offspring. Unfertilized rainbow trout eggs were treated with three different concentrations, fertilized, and resulting juveniles were observed throughout development. Aluru et al. (2010) concluded that oocyte exposure to BPA leads to modified stress performance, delayed hatching times, and growth suppression in juvenile rainbow trout. The following image is taken from Aluru et al. (2010), showing both the decrease in body size and production of yolk observed in juvenile rainbow trout hatched from BPA-exposed oocytes.
Although pure BPA is not utilized in dental resins, it has been demonstrated that bis-DMA has the ability to be hydrolyzed into BPA by salivary esterases.1 This is a potential cause for concern due to the many adverse health effects associated with BPA. These effects are presumably due to the ability of BPA to bind to nuclear estrogen receptors and interfere with endocrine signaling.1 Thus, it is of interest to determine the estrogenic potential of dental resins over time.
Which means their obviously bad for the aquatic marine life environment & are cause many different forms of damage for them & us as one. On p.g. 23 of The New York Times upfront magazine “Birds,fish, sea turtles, & others are getting tangled in plastic bags or mistake them for food & choke”. Someone else might argue that they could the plastic bags in landfills instead of oceans. But that counter- argument is flawed because you’re just polluting by burning plastic which is bad on our part we’re not doing our part to support & taking care of the earth. Plastic in the ocean isn't just bad for plants & animals but for humans too because of the food chain some of us eat animals as a meat source such as aqua marine life like fish. If the fishermen catch fish that have been eating plastic then it's in our food supply if we eat that fish it's gonna be bad for us so many will end up getting sick from the plastic inside of the fish then what will we do our aqua marine food supply will go down the drain we couldn’t eat the fish since it's basically contaminated with plastic that we’re dumping there instead of trying to fix it & getting rid of plastic bags for good for the good of the earth. We’re causing damage towards the earth by dumping all that plastic into the ocean which damages our water supply it’ll poison us although we clean the water it depends on how big the plastic particles are, it’ll make us sick & sense it’s been lying in the oceans could bring in new pathogens &
Today people are using pesticides and hormones in many of the items that we use each day and it’s affecting our society in various ways. Pesticides are used in many different ways including: keeping insects away from plants, controlling weeds, and controlling the spread of diseases to plants. Hormones make animals grow faster and/or produce leaner meat for food. Although some people believe that pesticides and hormones should be used to help crops and livestock, they can be very harmful to others as well as the environment.
Neurobehavioral and developmental deficits occur in newborns and through school-aged children who had in utero exposure to PCBs.
Everyday millions of Americans come in contact with many different forms of plastics and think nothing about it. Whether its drinking from water bottles purchased at your local super market to eating leftovers from food storage containers in your refrigerator, plastics are everywhere in the world and it seems as if they’re here to stay. But have you heard of the chemical Bisphernol-A? Also known as BPA, this chemical compound is found in just about every plastic that you come in contact with and has created quite the uproar in the media over the last several years in question on its safety for consumer use. Scientists from around the world believe that BPA is the cause of many adverse health effects found in infants and adults, but the scientists aren’t the only ones voicing their opinions on the subject. Many concerned consumers in light of recent studies on the controversial BPA chemical are worried about what they themselves and their families are ingesting and exactly how it is affecting them. This problem amongst consumers has been so great that many companies such as Wal-Mart have demanded the removal of baby and infant products that contain the controversial chemical BPA from their store shelves.
Every year, an estimated 8 million tons of plastic waste enters our environment, severely polluting oceans, beaches, forests, and even the towns and cities we live in. In the ocean alone, it is believed that 5.25 trillion pieces of plastic pollutes the waters (“Plastic Statistics”, Ocean Crusaders).The majority of plastic pollution can be traced back to single-use items, such as grocery bags, bottles, and plastic packaging. According to United Nations Environment, “At the rate we are dumping items such as plastic bottles, bags and cups after a single use, by 2050 oceans will carry more plastic than fish…” (“UN Declares War on Ocean Plastic”, UN Environment). This pollution is a major problem and endangers not only the environment, but human
The general function of the endocrine system is gland based to produce hormones that help with metabolism, growth, tissues, and reproduction. The structure between the nervous system and endocrine system are very similar the basics of both systems involve triggering glands throughout the body from receptors. The function on the other hand is a little different because the nervous system makes a fast response through specific glands and muscles. While the endocrine system is more widespread it also works at a slower pace.
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.
Most individuals are exposed through diet via BPA leaching from food containers, food packaging or plastic bottles, while there is still risk from air, dust, and water (National Institute of Environmental Health Sciences, 2013). There are many reason why there needs to be stricter guidance and regulations on the release of BPA in household items such as baby bottles, plastic food containers, and canned goods to name a few. Some reasons why these countries are banning BPA are due to its ill effect on people. BPA is considered to be an endocrine-disruptive chemical, which have been linked through laboratory testing to developmental issues, diabetes, cancer and other ailments (Bardelline, 2011). Canada, most of the European Union, China, South Africa and Malaysia have all collectively banned BPA usage in different forms.
There have been plenty of recent studies of the affects of BPA. The enzymatic chemical is released in...
CHEMICHALS: Scientist have defined hundreds of chemicals that can cause cancer in animals. These chemicals are also a cancer hazard for human beings if they become widespread in food supply, the general environment, or the living and working environment. In most cases, a chemical carcinogen enters the food supply as a food addi...
Most people fear that BPA will have negative effects on their health, such as reproductive issues and cancer.... ... middle of paper ... ...2014. The 'Standard' of the 'Standard'. http://www.onlineeducation.net/bottled_water/water_full.jpg>.
Sul, Juliana A. Ivar Do, and Monica F. Costa. "The Present and Future of Microplastic Pollution in the Marine Environment." Environmental Pollution (2013): n. pag. Print.
You might recall first hearing about the toxic chemical BPA, back in the late 2000s when it was found that many common plastic items contained this toxin [http://www.bbc.com/news/science-environment-39217985]. These plastics containing BPA release a synthetic estrogen, creating serious health-related issues [https://www.bcm.edu/news/molecular-and-cellular-biology/potentially-safer-substitutes-for-bpa]. Unfortunately, later testing revealed that even plastics such as polypropylene, that claimed to be BPA-free, still test positive for leaking synthetic estrogens
Fertilization (conception) is the moment in which the sperm cell enters the oocyte and merges with it. From this moment, the cell division begins: at each division the number of cells is doubled in the fertilized egg. About two days after fertilization, the fertilized egg migrates the remaining way of the fallopian tube down to the uterus, where the implantation takes place. So that it can even come to the fertilization, some conditions are necessary, which will all together lead to the sperm and egg cell coming together. This is how fertilization works: After ovulation, the ovum migrates in the fallopian tube towards the uterus. In the next twelve to 24 hours she is fertile. The sperm arriving at the ovum try to drill through its shell. Fertilization