Rainbow Trouts

As one of the most domesticated fish, rainbow trout can spawn successfully in captivity at water temperatures between 2 to 15°C. The timing of gonadal recrudescence, maturation and spawning maturation is controlled by the seasonally changing cycle of day length (photoperiod). The rainbow trout population in India usually spawns in autumn-winter (November to January) associated with decreasing water temperatures. Under normal conditions, one batch of eggs is produced each year and stripped on a single occasion. Each female can shed anywhere from 1000 to 4000 large eggs (with an average fecundity of about 2000 eggs per kilogram body weight). The normal stripping practice is to run off eggs from multiple females and fertilize it with milt from

Rain washes the pesticides that are used in our Australians households and then become run-off in drains and sewers. They then make their way into nearby water bodies, wether that be creeks, rivers or even oceans and settle within the soil by sticking to small particles, including tiny living organisms like phytoplankton (M. Barwick, 2003, pp. 471-502). Small fish consume these tiny organisms, which may then be eaten by a larger organism and this continues until the top order consumer is reached. The concentration that first began in the phytoplankton and has multiplied sufficiently as it moves along the food chain. The amount of the pesticide has reached a highly toxic level in the top order predator, whether that is birds or even humans. As a result of the biomagnification of pesticides and other chemical the marine environment and the organisms that live within it are heavily affected. The build up of heavy metals, for example, it interferes with the formation of red blood cells, creates liver and kidney implications and forms reproductive defects in many organisms. This hinders an organism’s ability to survive and reproduce and can create a decline in species

River water near the spill showed elevated levels of lead and thallium, Mercury and arsenic cadmium and lead exceeding Clean Water Act standards designed to protect aquatic life as well as humans who come in contact with the water. Which can cause birth defects and nervous and reproductive system disorders?

For example, the chemicals could leak into a local water supply through surface runoff and eutrophication could occur. This is where an algae bloom takes place resulting in the depletion of oxygen disabling plants such as pondweed to respire and therefore die. These then decompose and with a high build up of toxic chemicals the fish of the freshwater lake or pond then die too.

The study compared the crab tissue of Vieques crabs and Puerto Rican mainland crabs. Fiddler crabs collected in the firing range contained significantly higher concentrations of copper, zinc, nickle, cobalt, and cadmium. The crabs were found to have up to 20 times the normal levels of cadmium and cobalt, both carcinogenic metals, which means exposure, increases the risk of getting several cancers. Both birds and humans eat crabs. Human ingestion of cadmium, which isn’t easily digestible, may cause hypertension or nausea. Prior to 1979, cancer, birth defects, and mortality rates were lower in Vieques than in the mainland. From 1985-86 the incident ratios for Vieques exceeded alert levels, surveillance done by the Agency for Toxic Substances and Disease Registry. From 1990-1995, the likely hood of giving birth to underweight babies is 65.3% more than on the mainland. In 1997, the mortality rate was 47% greater than the mainland’s mortality rate.

A lot of local waste water and waste dumps use fossil fuels containing some copper particles to produce fertilizers and other natural sources like vegetation’s and sprays. Thus, copper is very prevalent in the environment. There was about “1,400,000,000 pounds of copper released into the environment in the year 2000”. As copper is being released it binds strongly to organic material in the soil. Meaning there is cooper compounds that get into the ground water and eventually reached rivers and lakes. The indoor effect of copper comes mostly from the burning of things like heaters and propane tanks that use copper tubing to get indoors. Basic copper does not break apart in the

The environmental effects of gold mining are that cyanide is extremely toxic to birds and mammals drawn to these ponds in search of water. The ponds can also leak or overflow, posing threats to underground drinking water supplies and fish and other forms of life nearby lakes and streams. Snow and heavy rains washed out an earthen dam on one end of a cyanide leach pond at a gold mine in Romania. Several hundred thousand people living along these rivers were told not to fish or to drink or withdraw water from affected rivers or from wells along the

Based on the results of the present work, one may be tempted to infer that hepatopancreas levels as low as 50 µg/g dw may be life threatening to C. aspersus juveniles. This metal was not only frequently reported to accumulate to higher concentrations in the hepatopancreas of different land snail species without causing lethality, but it is also homeostatically regulated in eukaryotes (Balamurugan and Schaffner, 2006), thus drastically limiting the use of gastropod soft tissue levels as a toxicicity biomarker. Therefore, such reference values are difficult to be used for assessing the environmental hazard of soil copper. However, recent data provide evidence that rhogocytes from the hepatopancreas of land pulmonates may function as a sensitive endpoint for this purpose. These cells contain Cu in granular form, which unlike the metallothionein-bound form, is responsive to overphysiological uptake (Dallinger et al., 2005). As a result, future studies should be conducted for assessing tissue levels over which it can induce toxic effects on terrestrial gastropods. It is also necessary to identify the precise contribution of various additional factors (e.g., chemical form, snail age, species, and metabolic status, etc.) on the degree to which this metal accumulates in land snails and the corresponding toxic effects. Moreover, it is suggested to develop molecular biological techniques to strengthen and facilitate this research. Emphasis should be on gene(s) involved in synthesizing the specific metallothioneins and gastropod homologues of genes for copper tolerance in other invertebrates (Nica et al., 2013). Such fundamental work must be accomplished before standardizing a targeted ecotoxicological test with C. aspersus juveniles

Lead and sodium tungstate were studied for their effect on earthworms and other organisms. Lead was found to be the most lethal and harmful of the low levels and sodium tungstate. The sodium tungstate was much less toxic but it completely went against their reproductive process and

This experiment was carried out to understand how Gammarus are exposed to Zinc over a duration of 60minutes. The LC50 was calculated to understand if there is lethal concentration to 50% morality of organisms. In this experiment zinc was used as the toxic product and the organism used was Gammarus. LC50 values were at 45 minutes and 60 minutes. The LC50 value for 45 minutes was 36mg/L and the LC50 value for 60 minutes was 20mg/L.

Ground water forms a large percent of all the used water on the earth. And as it cannot be seen, it is usually overlooked or ignore when considering all the water on the earth. Since aquifer is valuable source, protecting it form pollution and managing its use carefully will guarantee its future as an important part of eco-system and human activity. Recently, industrial applications of toxic heavy metals have caused dangerous environmental problems. This essay will show the effect of aquifer polluted by some contaminants such as Cr (III), Fe(III), Cu(II), Cd(II), and Pb(II) or radioactive materials on people, plants and animals. In addition, it will demonstrate the best treatment and preventative methods. Furthermore, it will argue that the pretreatment of industrial wastes is the best way to prevent the pollution in ground water.

P. oceanica meadows are met in transparent and pure waters of Mediterranean area. The prevalence of Posidonia meadows in clear water is a useful tool for biomonitoring the clearness of the desired area. Along with Mytilus galloprovincialis, the Mediterranean mussel, Posidonia is a natural reservoir of different metals acquired from the environment. These metals are released from industrial, agricultural and urban activities in the coastal area and are one of the most persisting pollutants in the environment (Bethoux et al. 1990). Due to its sessile property, Posidonia is an ideal organism for biomonitoring. In a study conducted to compare the bioaccumulation level between M. galloprovincialis and P. oceanica, for cadmium, cobalt, chromium, nickel and lead, P. oceanica

In a sample of 200 fish from the Madre de Dios River near mining operations, 56% of the fish had mercury levels which exceeded the World Health Organization’s acceptable guidelines by 0.5 mg kg-1 subsequently posing a health hazard to local communities (Diringer et al., 2015).

One of the challenges surrounding scholarly work on toxicity and cancer is related to the number of variables that may also contribute to cellular death. In addition, cancers from environmental toxicity may take years or decades to fully develop, and some types of toxicity mimic other afflictions. One such example is in the maternal transfer of heavy metals during fetal development that

Chronic cadmium poisoning can result in nephrotoxicity, osteoporosis, cardiovascular diseases, testicular necrosis, prostatic and testicular cancers, renal failure and neurodegenerative conditions (Yu et al., 2007). Moreover, it was reported that spermatogenesis is disturbed by free radical toxicity (Aruldhas et al., 2005) . It depletes many essential metal antioxidants including selenium in the body (Sato and Takizawa, 1982). Apparently, its exposure results in decreases of glutathione (GSH) levels which causes an increase in reactive oxygen species leading to increase in lipid peroxidation, change intercellular stability, damage deoxyribonucleic acid (DNA), membranes and consequently inducing cell death (Stohs et al., 2000). The metal accumulates in human body affecting negatively several organs: liver, kidney, lungs, bones, placenta, brain and central nervous system (Castro-González and Méndez-Armenta, 2008). Therefore, the maximum concentration limit for cadmium (II) ions in drinking water must be strictly regulated. The World Health Organization (WHO), set a maximum guideline concentration of 0.003 mg/L for cadmium (II) in drinking water (WHO, 2008). Hence, there is great interest regarding the removal of cadmium from wastewater streams.