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Reproductive Toxiciity
- 1. Effect on male and female reproductive systems:
- - Male: a) affect division of sperm cells
- b) development of healthy sperm
- - Female: Affects:
- a) the endocrine system
- b) the brain
- c) the reproductive track
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Immunotoxicity:
- - Toxic affects on the immune system include:
- a) the lympth system
- b) the blood cells
- c) antibodies in the blood
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Neurotoxicity 5
- 1. The toxic effects on the nervous system
- a) the CNS - Central Nervous System
- b) the PNS - Peripheral Nervous System
- 2. CNS includes brain and spinal cord
- 3. PNS includes the remaining nerves - Sensory and Motor
- 4. Neurotoxic Effects - two basic types
- a) Destruction of nerve cells
- b) interference with neurotransmiters
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Lethal Dose or Lethal Concentrations
- 1. Concentration of toxicant at which a specific percent of test animals die.
- 2. Expressed as the mass of toxicant per unit mass of test animal LD50 implies 50% of animals died.
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Pathogens 6
- 1. Many infectious diseases caused by ...
- 2. Found in fecal wastes
- 3. Transmitted and transfered through wastewater
- 4. Some shellfish concentrate pathogenic organism in tissue -> toxic
- 5. Pathogens: some protozoa, viruses, helminths (worms )
- 6. Not all microorganisms are pathogens. Some are useful in wastewater treatment.
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Nephrotoxicity 8
- 1. Excrete ammonia as urea getting rid of metabolic wastes
- 2. Maintain blood pH by exchanging hydrogen ions for Sodium ions as needed
- 3. Maintain ion and water balance by excreting ions and water
- 4. Secrete hormones to regulate blood pressure
- 5. Like the liver, the kidneys detoxify
- 6. Lead, Mercury, Cadmium - cause cell function death -- metals can be stored in kidneys interfering with functioning enzymes.
- 7. Chloroform and other organic material -> cell dysfunction, death, cancer.
- 8. Ethylene Glycol can cause renal failure from obstruction of normal flow of liquid through kidneys.
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Microbe Categories 4
- 1. Phototrophes - rely only on the Sun for energy
- 2. Chemotrophs - extract energy from organic or inorgaic oxidation/Reduction
- 3.Organotrophs - use organic materials
- 4. Lithotrophs - oxidize inorganic compounds
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Bacteria Growth - More efficient temperatures
- 1. Most microorganisms in wastewater treatment processes : Bacteria
- 2. Treatment plant conditions so: Chemoheterotrophs predominate
- 3. Bacteria type ---> Best temp range 4 growth
- psychrophiles -----> below 68 degrees F (20 C)
- mesophiles -----> 68 deg F (20C) to 113 F (45F)
- thermophiles --> 113 deg F (45 C) to 140 F (60 C )
- stenothermofiles -> avove 140 deg F ( 60 C)
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Heterotrophs vs. Autotrophs
- Heterotrophs - Use organic material as a carbon supply
- Autotrophs -Require only carbon dioxide to supply their carbon needs
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Toxic Effects o Eye
- 1. Wide variety of Toxic Substances
- 2. Through contact with Cornea cause damage to eye
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Carcinogen Toxicants 5
- 1. No apparent threshold
- 2. Any dose is considered to have an effect. May be unmeasured at low doses
- 3. No safe exposure level
- 4. Linear relationship ( Dose Response )
- 5. Lead is an example of such a toxicant
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Dose - Response Relationships 3
- 1. Relates the response of an organism to increasing levels of Toxicants
- 2. Toxicity Test Objectives: Establish Dose Response Curve.
- 3. Dose Response Curves
- a) Response: The Ordinate - y axis
- b) Dose: The abscissa - x axis
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Features of the Dose Response Curve:
- 1. No Observed Effect - upper end range Threshold.
- - the No affect level (NEL) or No observed effect level (NOEL)
- 2. Lowest Observed Effect - The dose where minor effects can first be measured (LOEl)
- 3. No Observed Adverse Effect - where effects related to the response being measured 1st can be measured. (NOAEL)
- 4. Lowest Observed Adverse Effect - Where effects 1st measured similar to higher doses (LOAEL)
- 5. Frank Effect - where max effects are observed with little change for change in dose (FEL)
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Heterotrophic Bacteria
- 1. Use organic material as both an energy source and a carbon source.
- 2. Subdivided depending on free O2 use:
- a) Aerobes - Obligate Aerobes require free dissolved O2.
- b) Anaerobes - Obligate Anaerobes oxidize in complete absence of O2.
- c) Facultative Bacteria -
- - use dissolved O2 when available
- - behave anaerobicly inarobic conditions
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