Unit 7

• Heavy metal toxicity can manifest in neurological symptoms like tremors, headaches, decreased coordination, and memory issues.
• What are three heavy metals?

  lead, arsenic, mercury
• Acid deposition occurs when...

  burning coal and volcanic activity. This releases sulfur and nitrogen dioxide
• Sulfur and nitrogen dioxide are converted into sulfuric acid and nitric acid
• Acid deposition reduces the pH of water bodies and soil
• Coal burning facilities install coal scrubbers to prevent acid deposition.
• Describe the effects of acid deposition in aquatic organisms.

  Acidic rainwater contains aluminum, which flows into lakes. This messes with pH levels. Animals have different tolerances, but with a pH below 5, most fish eggs cannot hatch
• Describe the impacts of acid deposition on terrestrial biomes.

  Trees can die, and aluminum removes NPK nutrients from soil
• The four types of synthetic compounds are pesticides, pharmaceuticals, military compounds, and industrial compounds.
• Pesticides harm organisms because they biomagnify.
• Pharmaceuticals and perchlorates are endocrine disruptors.
• PCBs are sourced from poorly maintained waste sites through leaks, dumping, disposal, and combustion.
• PCBs can cause birth defects, nervous system, reproductive, and brain damage, learning disabilities, paralysis, ADD, feminization, and cancer.
• Bioaccumulation


  an increased chemical concentration of a chemical within an organism at a given time
• biomagnification


  increase in a chemical concentration as it goes up the food chain
• persistence


  the length of time a chemical remains in the environment
• Describe mercury's source.


  Released into atmosphere through burning of coal and garbage; once airborne it can enter water bodies
• Describe how to remove mercury.

  replacement of old pipes and paint, water filtration, laws and regulations
• describe arsenic's source

  earth's crust, dissolved groundwater
• describe how to remove arsenic

  water filtration
• what cancers can arsenic cause?

  Lung, skin, bladder, and kidney cancer.
• describe lead's sources

  lead-lined pipes in plumbing fixtures, paint, solder, brass fittings, older buildings
• describe how to remove lead

  replace old pipes and paint, water filtration, laws and regulations
• Lead exposure can cause nervous system, kidney, and brain damage.