1 / 23

Ecotoxicology

Ecotoxicology. The study of the effects of pollution on the environment Come from 2 words Eco – house Toxicum – poison Human activities are the main factor that are studied in this field. Contaminants.

glyn
Download Presentation

Ecotoxicology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ecotoxicology • The study of the effects of pollution on the environment • Come from 2 words • Eco – house • Toxicum – poison • Human activities are the main factor that are studied in this field

  2. Contaminants • Any type of substance or radiation that is likely to cause harm to one or more ecosystems • Ex.: Lead, arsenic, phosphorus, mercury, bacteria, uranium, insecticides, pesticides, PCBs • The toxicity of a contaminant depends mainly on 3 factors: • Concentration • Types of organisms it comes into contact with • Length of exposure

  3. Toxicology • The study of poisonous substances and their effects on living things • How much poison does it take to kill something living – Lethal dose • Toxicity threshold is the level of concentration above which a contaminant becomes harmful to an organism • Physical and neurological effects

  4. Dichlorodiphenyltrichloroethane DDT

  5. A Silent Spring http://www.cbsnews.com/news/the-legacy-of-silent-spring/

  6. Bioaccumulation • The tendency of certain contaminants to build up over time in living tissues • High levels of DDT in tissues are linked to several forms of cancer, diabetes and neurological disorders, specifically in babies that are fed contaminated breast milk • DDT is used to spraying crops in 3rd world countries and has decrease malaria significantly

  7. Bioconcentration • The concentration of contaminants in the living tissues tends to increase with each trophic level • Effects of mercury poisoning have been linked to impaired neurological development (especially in infants), cancer and death • Mercury seeps into our water because of runoff and gets into the food chain • Humans have the some of the highest concentrations of mercury because we occupy the highest orders of the food chain

  8. FYI- Biotechnological solutions BIOREMEDIATION • Using bacteria to break down organic toxins into inorganic material by a process called biodegradation PHYTOREMEDIATION • Using plants or algae to eliminate contaminants WASTEWATER TREATMENT • The process of removing from our water supply waste products such as microorganisms, decomposing waste, algae, chemicals, etc. • Use of septic tanks • Waste water treatment plants WHY NOT LIMIT THE POLLUTION WE PRODUCE?

  9. Soil (EST)

  10. Soil • The thin top layer of the Earth’s crust • Soil forms when rocks become broken up into smaller pieces and mixes with decomposing organic matter • Functions of soil: • Provide a place for plants to put down roots • Provide minerals, nutrients and moisture to plants • Home for microorganisms and decomposers • Soil is fertile when: • Sufficient minerals, adequate moisture & appropriate pH

  11. Buffering capacity • Buffer: substance that resists pH changes • Soil acts like a buffer, resisting changes in pH in order to maintain a hospitable living environment for many life forms • Finer soil = better buffer • Why should pH remain stable? • Ideal soil pH?

  12. Soil Depletion • The loss of soil’s fertility • Why it happens: • Farming practices cause the compaction of soil. • Compacted soil does not allow oxygen and water to be absorbed. • Nutrients and microorganisms essential for plant life run off the soil into lakes and rivers. http://www.youtube.com/watch?v=zumM4a3HI7U

  13. Soil Contamination • Can come from a variety of sources: • Radioactivity • Acid Rain (H2SO4 and HNO3 forming in the atmosphere from industrial processes) • Pesticides

More Related