Environmental toxicology

Environmental toxicology is a multidisciplinary field of science concerned with the study of the harmful effects of various chemical, biological and physical agents on living organisms.

Harmful effects of such chemical and biological agents as toxicants from pollutants, insecticides, pesticides, and fertilizers can affect an organism and its community by reducing its species diversity and abundance.

[7] 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.

Apart from targeting these specific areas, it also established a national operating that "permits program to make the law more workable, and strengthened enforcement to help ensure better compliance with the Act.

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.

[13] 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.

In Canada, a study examined genetic diversity in wild yellow perch along various heavy metal concentration gradients in lakes polluted by mining operations.

In response to high heavy metal concentrations a Dipteran species, Chironomus riparius, of the midge family, Chironomidae, has evolved to become tolerant to cadmium toxicity in aquatic environments.

[17] Additionally, a case study in China looked at the concentrations of Cu (copper), Cr (chromium), Cd (cadmium), and Pb (lead) in the edible parts of the fishes Pelteobagrus fluvidraco, the banded catfish, and Cyprinus carpio, the common carp living in Taihu Lake.

[14] These metals were actively being released from sources such as industrial waste stemming from agriculture and mining and then going into coastal ecosystems and becoming stored in the local fish, especially their organs.

The most known or common types of heavy metals include zinc, arsenic, copper, lead, nickel, chromium, aluminum, and cadmium.

[21] Those natural processes release more aluminum into the freshwater environments than do humans, but anthropogenic impact has been causing values to rise above the recommended amount by the U.S. EPA and World Health Organization.

[21] Finally, the metal causes slow responses to arousal and other environmental stimuli, overall abnormal behavior, and changes with the neurotransmitters in their bodies such as adrenaline and dopamine.

It is "semimetallic property, is prominently toxic and carcinogenic, and is extensively available in the form of oxides or sulfides or as a salt of iron, sodium, calcium, copper, etc.

"[20] It is also one of the most abundant elements on earth and its specific inorganic forms are very dangerous to living creatures (animals, plants, and humans) and the environment.

Those who experience acute poisoning have symptoms such as appetite, headache, hypertension, abdominal pain, renal dysfunction, fatigue, sleeplessness, arthritis, hallucinations and vertigo.

[23] Because of these worrying side effects, there was a study done in the Pacific coast of Columbia to assess the levels of mercury in the environment and in the people living there from gold-mining.

[23] They also determined that approximately 44% of the total sites around the river had a moderate level of pollution, further emphasizing that more intervention programs should be conducted to curb the seepage of mercury into the environment.

[23] In the end, the highest levels of total airborne mercury were found to be in the gold shops downtown, further emphasizing the cost of gold-mining in such native communities and the need for better programs directed towards preventing its spread.

[20] Though cadmium was used as replacement for tin in WWI and pigment in paint industries back in the day, currently it is seen mostly in rechargeable batteries, tobacco smoke and some alloys production.

[citation needed] Pesticides in general have been shown to negatively impact the reproductive and endocrine systems of various reptiles and amphibians, so much that it is cautiously thought to be one of the main factors behind the decline in their populations all over the world.

[25] For example, a study done on male African clawed frogs show that exposure to atrazine led to smaller testicular size and lower testosterone levels.

[27] A build-up of lactate and ammonia also resulted, leading to liver failure, tissue hypoxia, lactic acidosis, muscle fatigue, and pain.

Following this discovery, DDT was widely used by farmers in order to kill agricultural pests such as the potato beetle, codling moth and corn earworm.

Exposure to fluoride alters ion balance, total protein and lipid levels within these fish, which changes their body composition and disrupts various biochemical processes.

The chemicals are also used in fracking, artificial grass, lubricants (mechanical, industrial and bicycle), food packaging, magazines, pesticides, refrigerants, and even surgically implanted medical devices.

Remediation of these "forever chemicals" has been attempted in hot spots around the world, by placing the contaminated soil in landfill or heating at extremely high temperature.

[40] These substances are found in pesticides, herbicides, and insecticides and were generally thought to be safe because they degrade quickly in the natural environment assuming there is sunlight, air, and soil.

[40] In a specific case study, organophosphate pesticides like chlorpyrifos, diazinon, fenitrothion, and quinalphos used in agriculture in the northwestern part of Bangladesh were found to have high or acute ecological risks on the surface water and soil for aquatic insects and crustaceans.

The results of hospitilation include: Vomiting, kidney damage (due to lose of water, protein and electrolytes) fever, bloody diarrhea, and headaches.