User:Gabyruelas/New sandbox

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Governing Policies on Environmental Toxicity[edit]

U.S Policies[edit]

To protect the environment, The National Environmental Policy Act (NEPA) was written[1]. The NEPA act focused on sure that all of the branches of government take into consideration the environment before any huge federal actions. Since some federal actions could potentially affect the environment, it was crucial to restrict the government from taking actions that could negatively affect the environment. This law was passed in 1970 and also founded the Council on Environmental Quality (CEQ).[2] The importance of CEQ was that it helped further push policy areas.

CEQ created helpful environmental programs that were very beneficial. Some include, the Federal Water Pollution Control Act (RCRA), Toxic Substance Control Act, Resources Conservation and Recovery Act (RCRA and the Safe) .[3] CEQ was essential in creating the foundation for most of the recent environmental legislation. The only exception was for Superfund and asbestos control legislation.[2]

Some initial impacts of NEPA pertain to the interpretation within Courts. Not only did Courts interpret NEPA to expand over direct environmental impacts from any projects, specifically federal, but also indirect actions from federal projects.[2]

Toxic Substance Control Act[edit]

TSCA, also known as the Toxic Substance Control Act, is a federal law that regulates industrial chemicals that have the potential to be harmful to humans and the environment.[4] TSCA specifically targets areas such as use, storage, degradation of chemicals in commercial use, manufacture and importation.[4] The EPA allows the following to be done:"1. Pre-manufacture testing of chemicals to determine health or environmental risk 2. Review of chemicals for significant risk prior to the start of commercial production 3. Restriction or prohibition on the production or disposal of certain chemicals 4. Import and export control of chemicals prior to their entering or leaving the USA."[4]

The Clean Air Act[edit]

The Clean Air Act was aided by the signing of the 1990 amendments. These amendments protected reducing acid, the ozone layer, improving air quality and toxic pollutants.[5] The Clean Air Act was actually revised and with, support from President George H.W Bush, it was signed in.[5] The biggest major threats that this act targets are: urban air pollutions, toxic air emissions, stratospheric ozone, acid rain etc. Apart from targeting these specific areas, it also established a national operating that allows programs to create the law in order for it to be more workable. Not only this, but it also strengthened enforcement to aid in ensuring better compliance with the act.[5]

Regulations and Enforcement Actions on PCBs[edit]

PCBs pertain to a group of human-produced organic chemicals known as Chlorinated hydrocarbons.[6] The chemical and physical properties of a PCS determine the quantity and location chlorine and unlike other chemicals, they have no form of identification.[7]The range of toxicity is not consistent and because PCBs have certain properties ( chemical stability, non-flammability) they have been used in a colossal amount of commercial and industrial practices. Some of these industrial practices include, heat transfer, rubber products and pigments, dyes and carbonless copy paper, plasticizers in paints, and electrical.[8]


Though the United States did ban the use of PCBs, there is the possibility that they are present in products made before the PBC band in 1979. The Environmental Protection Agency released its ban on PCBs on April 19th, 1979.[9]According to the US Environmental Protection Agency, "Although PCBs are no longer being produced in this country, we will now bring under control the vast majority of PCBs still in use," said EPA Administrator Douglas M. Castle. By doing so, it would help prevent further contamination of our water, food supplies, and air from a toxic and very persistent man-made chemical.[10]

PCBs has been tested on laboratory animals and have caused cancer and birth defects. PCB is suspected of having certain effects on liver and skin of humans. They are also suspected of causing cancer as well. EPA, estimates around 150 million pounds of PCBs are thrown out throughout the environment, which can potentially contaminate air and water supplies. Another 290 million pounds are located in landfills of the country.[11] Again, even though they have been banned, there is still a large amount of PCBs are circulating within the environment and are possibly causing effects on the skin and liver of humans.

There were some cases in which people or companies that disposed of PCBs incorrectly. Up until now, there have been four cases in which EPA had to take legal actions against people/companies for their methods of disposal. The two cases involving the companies, were fined $28,600 for improper disposal. It is unknown what fined was charged against the three people for, "illegally dumping PCBs along 210 miles of roadway in North Carolina."[12]

Though PCBs were banned, there are some exceptions where they are being used. The area in which it has been completely prohibited is, " the manufacture, processing, distribution in commerce, and "non-enclosed" (open to the environment) uses of PCBs unless specifically authorized or exempted by EPA. "Totally enclosed" uses (contained, and therefore exposure to PCBs is unlikely) will be allowed to continue for the life of the equipment."[13] In terms of electrical equipment containing PCBs is allowed under specific controlled conditions. Out tof the 750 million pounds of PCBs, electrical equipment represents 578 million pounds. Any new manufacture of PCB is actually prohibited though[14].

Metals Toxicity The most known or common types of heavy metals include zinc, arsenic, copper, lead, nickel, chromium and cadmium. All of these types cause certain risks on human and environment health.

Though certain amount of these metals can actually have an important role in, for example, maintaining certain biochemical and physiological, "functions in living organisms when in very low concentrations, however they become noxious when they exceed certain threshold concentrations."[15] Heavy metal are a huge part of environmental pollutions and their toxicity is a problem of increasing significance for ecological, evolutionary, nutritional and environmental reasons.[16]

Person has been exposed to Arsenic poisoning through contaminated water
Arsenic[edit]

Arsenic, one of the most important heavy metals, causes health problems within ecological and humans. It is, a semimetallic property, and a very present toxic and carcinogenic. Arsenic is also available in the form of calcium, copper, oxides or sulfides, iron etc. [17] Not only that, but it is also the most abundant element here on earth and its specific inorganic forms are very dangerous to living creatures (animals, plants, and humans) and the environment.

Effects of Arsenic on humans is that they can cause cancer in the bladder, skin, lungs and liver. One of the major areas in which humans are exposed to arsenic is through contaminated water which is a problem in more than 30 countries in the world.

Humans tend to encounter arsenic through industrial sources or natural means. They can also encounter them through unintended/ unknown sources.[18] Water can become contaminated by arsenical pesticides or just natural arsenical chemicals. There are some cases in which arsenic has been used in suicidal attempts and can result in acute poisoning. Arsenic, is a protoplasmic poison which means that arsenic can can damage or kill living cells. It mostly affects the sulphydryl group of cells and that causes the malfunctioning of cell respiration, mitosis cell and enzymes.[19]

Lead[edit]

Another extremely toxic metal, lead can and has been known to cause environmental contamination and extensive health problems in many parts of the world.[1] The physical appearance of lead is bright and silver colored metal. Some sources of lead pollution in the environment include Metal plating and fishing operations, soil waste, factory chimneys, smelting of ores, wastes from batter industries, fertilizers and pesticides and many more. Unlike, other metals such as copper, lead only plays a physiological aspect and no biological functions. In the US, "more than 100 to 200,000 tons of lead per year is being released from vehicle exhausts" and some can be brought in by plants, flow in water or fixation into the soil.[19]

Humans come in contact with lead through mining, fossil fuel burning. In burning, lead and its compounds are exposed into air, soil, and water. Lead can have different effects on the body and effects the central nervous system. Someone who has come in contact with lead can have either acute or chronic lead poisoning. Those who experience acute poisoning have symptoms that include, appetite, headache, hypertension, abdominal pain, renal dysfunction, fatigue, sleeplessness, arthritis, hallucinations and vertigo.[16] Chronic exposure on the other hand, can cause more severe symptoms such as, "mental retardation, birth defects, psychosis, autism, allergies, dyslexia, weight loss, hyperactivity, paralysis, muscular weakness, brain damage, kidney damage and may even cause death."[16]

Mercury[edit]

Equally as toxic as the previous heavy metals, Mercury, A shiny silver-white, can transform into a colorless and odorless gas when heated up. [16] Mercury highly affects the marine environment and there have been many studies conducted on the effects on the water environment. The biggest sources of mercury pollution include, discharges of industrial wastewater, mining, incineration, municipal wastewater discharges, and agriculture are all connected to water.[16] Due to their connection to water, they have very hight chance of getting mercury contamination.

Mercury exists in three different forms and all three posses different levels of bioavailability and toxicity. The three forms include, organic compounds, metallic elements and inorganic salts. As stated above, they are present in water resources such as oceans, rivers and lakes.[16] They are absorb by microorganism, and go through, biomagnification causing significant disturbance to aquatic lives. [15]

Mercury hurts marine life but can also be very hurtful towards humans' nervous system. Higher levels of mercury exposure can change many brain functions. It can affect memory problems, irritability, changes in vision or hearing, shyness.[15]

Cadmium[edit]

According to, ATSDR ranking, cadmium is the 7th most toxic heavy metal. Cadmium is interesting in that once it is exposed to humans (at work) or animals in their environment, it will accumulate inside the body throughout the life of the human/animal.[20] Though cadmium was used as replacement for tin in WWI and pigment in paint industries back in the day, now day it is seen mostly in rechargeable batteries, tobacco smoke and some alloys production.

As stated by the Agency for Toxic Substance and Disease Registry, more than 500,000 workers in the U.S. get exposed to toxic cadmium each year. It is also stated that the highest exposure to Cadmium can be seen in China and Japan. [15]

The effects of Cadmium on the kidney and bones is huge. It can cause bone mineralization the process of laying down minerals on a matrix of the bone"[21] . This can happen through renal dysfunction or bone damage.

Chromium[edit]

The 7th most abundant element, Chromium, can occur naturally when one burns oil and coal and is release into the environment through sewage and fertilizers. Chromium usage can be seen in, industries such as electroplating, production of paints and pigments, metallurgy, tanning, wood preservation, chemical production and pulp and paper production.[15]Chromium toxicity affects the biological processes in some plants such as wheat, maize, barley, vegetables, cauliflower, and citrullus. Chromium toxicity causes chlorosis and necrosis in plants. [15]

Pesticides[edit]

Pesticides are a major source of environmental toxicity. These chemically synthesized agents have been known to persist in the environment long after their administration. The poor biodegradability of pesticides can result in bioaccumulation of chemicals in various organisms along with biomagnification within a food web. Pesticides can be categorized according to the pests they target. Insecticides are used to eliminate agricultural pests that attack various fruits and crops. Herbicides target herbal pests such as weeds and other unwanted plants that reduce crop production.


DDT Example

Though DDT was banned in 1972, some of the pesticide (as well as other chemical) lingered in the environment. This lingering of toxic material led tto the near extinction of peregrine falcon. There was high levels of DDT were found in many areas such as tissues, eggs, and fat of the bird.[22] The government . worked with conservation groups in helping them breed out of the contaminated area. Finally, in 1999 the birds were taken off the U.S endangered species list.[22]

Sulfuryl fluoride[edit]

Sulfuryl fluoride is an insecticide that is broken down into fluoride and sulfate when released into the environment. Fluoride has been known to negatively affect aquatic wildlife. Elevated levels of fluoride have been proven to impair the feeding efficiency and growth of the common carp (Cyprinus carpio).[10] Exposure to fluoride alters ion balance, total protein and lipid levels within these fish, which changes their body composition and disrupts various biochemical processes.[10]

Cyanobacteria and cyanotoxins[edit]

Cyanobacteria, or blue-green algae, are photosynthetic bacteria. They grow in many types of water. Their rapid growth ("bloom") is related to high water temperature as well as eutrophication (resulting from enrichment with minerals and nutrients often due to runoff from the land that induces excessive growth of these algae). Many genera of cyanobacteria produce several toxins.[23][24] Cyanotoxins can be dermatotoxic, neurotoxic, and hepatotoxic, though death related to their exposure is rare.[23] Cyanotoxins and their non-toxic components can cause allergic reactions, but this is poorly understood.[25]: 589  Despite their known toxicities, developing a specific biomarker of exposure has been difficult because of the complex mechanism of action these toxins possess.[26]

Occurrence of Cyanotoxins in Drinking Water[edit]

The occurrence of this toxin in drinking water depends on a couple of factors. One, is the drinking water's level in raw source water and secondly, it depends on the effectiveness of removing these toxins from water when drinking water is actually being produced.[27] Due to being no data on the absence/presence of these toxins in drinking water, it is very hard to actually monitor the amounts that are present in finished water. This is a result of the U.S not having an state or federal programs in place that actually monitor the presence of this toxins in drinking water treatment plants.[27]

Effects of Toxins on Humans[edit]

Though data on the effects of these two toxins are limited, from what is available it suggests the toxins attack the liver and kidney. There was an hepatoenteritis-like outbreak in Palm Island, Australia (1979) due to the consumption of water that contained, "C. raciborskii, a cyanobacteria that can produce cylindrospermopsin."[27] Most cases (typically involving children) have required they be taken to a hospital. The results of hospitilation include: Vomiting, kidney damage (due to lose of water, protein and electrolytes) fever, bloody diarrhea, and headaches.[27]



  1. ^ US EPA, OA (2013-02-22). "Summary of the National Environmental Policy Act". US EPA. Retrieved 2019-03-03.
  2. ^ a b c US EPA, OA. "1988 Article on NEPA: Past, Present, and Future". 1988-article-nepa-past-present-and-future.html. Retrieved 2019-03-03.
  3. ^ US EPA, OA. "1988 Article on NEPA: Past, Present, and Future". 1988-article-nepa-past-present-and-future.html. Retrieved 2019-03-07.
  4. ^ a b c Schwartz, Dell'Aglio, Nickle, Hornsby-Myers, Michael D, Damon M, Richard, Jenniffer (15 July 2014). "Federal Environmental and Occupational Toxicology Regulations and Reporting Requirements: A Practical Approach to What the Medical Toxicologist Needs to Know, Part 1". Journal of Medical Toxicology : Official Journal of the American College of Medical Toxicology. 10 (3): 319–330. doi:10.1007/s13181-014-0410-7. PMC 4141923. PMID 25023223.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. ^ a b c [.https://www.epa.gov/clean-air-act-overview "Overview of the Clean Air Act and Air Poullution"]. {{cite web}}: Check |url= value (help)
  6. ^ US EPA, OSWER (2015-08-19). "Learn about Polychlorinated Biphenyls (PCBs)". US EPA. Retrieved 2019-03-10.
  7. ^ US EPA, OSWER (2015-08-19). "Learn about Polychlorinated Biphenyls (PCBs)". US EPA. Retrieved 2019-03-10.
  8. ^ US EPA, OSWER (2015-08-19). "Learn about Polychlorinated Biphenyls (PCBs)". US EPA. Retrieved 2019-03-10.
  9. ^ US EPA, OA. "EPA Bans PCB Manufacture; Phases Out Uses". epa-bans-pcb-manufacture-phases-out-uses.html. Retrieved 2019-03-10.
  10. ^ US EPA, OA. "EPA Bans PCB Manufacture; Phases Out Uses". epa-bans-pcb-manufacture-phases-out-uses.html. Retrieved 2019-03-10.
  11. ^ US EPA, OA. "EPA Bans PCB Manufacture; Phases Out Uses". epa-bans-pcb-manufacture-phases-out-uses.html. Retrieved 2019-03-10.
  12. ^ US EPA, OA. "EPA Bans PCB Manufacture; Phases Out Uses". epa-bans-pcb-manufacture-phases-out-uses.html. Retrieved 2019-03-10.
  13. ^ US EPA, OA. "EPA Bans PCB Manufacture; Phases Out Uses". epa-bans-pcb-manufacture-phases-out-uses.html. Retrieved 2019-03-10.
  14. ^ US EPA, OA. "EPA Bans PCB Manufacture; Phases Out Uses". epa-bans-pcb-manufacture-phases-out-uses.html. Retrieved 2019-03-10.
  15. ^ a b c d e f Jaishankar, Monisha; Tseten, Tenzin; Anbalagan, Naresh; Mathew, Blessy B.; Beeregowda, Krishnamurthy N. (2014-6). "Toxicity, mechanism and health effects of some heavy metals". Interdisciplinary Toxicology. 7 (2): 60–72. doi:10.2478/intox-2014-0009. ISSN 1337-6853. PMC 4427717. PMID 26109881. {{cite journal}}: Check date values in: |date= (help)
  16. ^ a b c d e f Jaishankar, Monisha; Tseten, Tenzin; Anbalagan, Naresh; Mathew, Blessy B.; Beeregowda, Krishnamurthy N. (2014-6). "Toxicity, mechanism and health effects of some heavy metals". Interdisciplinary Toxicology. 7 (2): 60–72. doi:10.2478/intox-2014-0009. ISSN 1337-6853. PMC 4427717. PMID 26109881. {{cite journal}}: Check date values in: |date= (help)
  17. ^ Jaishankar, Monisha; Tseten, Tenzin; Anbalagan, Naresh; Mathew, Blessy B.; Beeregowda, Krishnamurthy N. (2014-6). "Toxicity, mechanism and health effects of some heavy metals". Interdisciplinary Toxicology. 7 (2): 60–72. doi:10.2478/intox-2014-0009. ISSN 1337-6853. PMC 4427717. PMID 26109881. {{cite journal}}: Check date values in: |date= (help)
  18. ^ Jaishankar, Monisha; Tseten, Tenzin; Anbalagan, Naresh; Mathew, Blessy B.; Beeregowda, Krishnamurthy N. (2014-6). "Toxicity, mechanism and health effects of some heavy metals". Interdisciplinary Toxicology. 7 (2): 60–72. doi:10.2478/intox-2014-0009. ISSN 1337-6853. PMC 4427717. PMID 26109881. {{cite journal}}: Check date values in: |date= (help)
  19. ^ a b Jaishankar, Monisha; Tseten, Tenzin; Anbalagan, Naresh; Mathew, Blessy B.; Beeregowda, Krishnamurthy N. (2014-6). "Toxicity, mechanism and health effects of some heavy metals". Interdisciplinary Toxicology. 7 (2): 60–72. doi:10.2478/intox-2014-0009. ISSN 1337-6853. PMC 4427717. PMID 26109881. {{cite journal}}: Check date values in: |date= (help)
  20. ^ Jaishankar, Monisha; Tseten, Tenzin; Anbalagan, Naresh; Mathew, Blessy B.; Beeregowda, Krishnamurthy N. (2014-6). "Toxicity, mechanism and health effects of some heavy metals". Interdisciplinary Toxicology. 7 (2): 60–72. doi:10.2478/intox-2014-0009. ISSN 1337-6853. PMC 4427717. PMID 26109881. {{cite journal}}: Check date values in: |date= (help)
  21. ^ "Bone Mineralization Process". Bone and Spine. 2013-08-27. Retrieved 2019-03-10.
  22. ^ a b Wilkinson, Allie (2019-02-14). "50 years ago, DDT pushed peregrine falcons to the edge of extinction". Science News. Retrieved 2019-04-03.
  23. ^ a b Carmichael, Wayne (2008). "Chapter 4:A world overview--one-hundred-twenty-seven years of research on toxic cyanobacteria--where do we go from here?". In Hudnell, H. Kenneth (ed.). Cyanobacterial Harmful Algal Blooms: State of the Science and Research Needs. Advances in Experimental Medicine and Biology. Vol. 619. pp. 105–125. doi:10.1007/978-0-387-75865-7_4. ISBN 978-0-387-75865-7. PMID 18461766.
  24. ^ Agrawal, Anju; Gopal, Krishna (2013). Biomonitoring of Water and Waste Water. Springer, India. pp. 135–147. doi:10.1007/978-81-322-0864-8_13. ISBN 9788132208631.
  25. ^ Azevedo, Sandra MFO; Chernoff, Neil; Falconer, Ian R; Gage, Michael; Hilborn, Elizabeth D; Hooth, Michelle J; Jensen, Karl; MacPhail, Robert; Rogers, Ellen; Shaw, Glen R; Stewart, Ian (2008). "Chapter 26: Human Health Effects Workgroup Report". In Hudnell, H. Kenneth (ed.). Cyanobacterial Harmful Algal Blooms: State of the Science and Research Needs. Advances in Experimental Medicine and Biology. Vol. 619. pp. 579–606. doi:10.1007/978-0-387-75865-7_26. ISBN 978-0-387-75865-7. PMID 18461784.
  26. ^ van der Merwe, Deon (2014). "Chapter 31: Freshwater Cyanotoxins". In Gupta, Ramesh C. (ed.). Biomarkers in Toxicology. Elsevier. pp. 539–548. doi:10.1016/b978-0-12-404630-6.00031-2. ISBN 9780124046306.
  27. ^ a b c d EPA (June 2015). "Drinking Water Health Advisory for the Cyanobacterial Toxin Cylindrospermopsin" (PDF). {{cite journal}}: Cite journal requires |journal= (help)
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