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Toxins in our Environment, in us…

Toxins in our Environment, in us…. APES Fall 2008. Why should you care about Toxins?. We will address these topics today:. Movement, distribution, and fate of toxins How do we minimize the toxic effects? How do we measure toxicity?.

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Toxins in our Environment, in us…

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  1. Toxins in our Environment, in us… APES Fall 2008

  2. Why should you care about Toxins?

  3. We will address these topics today: • Movement, distribution, and fate of toxins • How do we minimize the toxic effects? • How do we measure toxicity?

  4. We need to consider this from three levels, or factors: • Factors relating to the toxin itself • Factors related to exposure to the toxin • Factors relating to the organism

  5. The Toxic Agent • What’s its composition? • It’s reactivity with the environs? • It’s solubility and state of matter (S,L,G, P) • Presence of impurities/contaminants • Availability of a vehicle to carry it • Movement of agent thru body tissues/cells

  6. Factors Related to Exposure • Dose received by victim • Route, rate and site of exposure • Duration of exposure • Frequency of exposure • Time of exposure (day, season,year)

  7. Factors Related to the Organism • Resistance to uptake, storage, cell permeability • Ability to metabolize, inactivate, sequester, or eliminate agent • Tendency to activate other substances to toxicity • Concurrent health issues/stresses • Species and genetic characteristics • Nutritional status of subject • Age, sex, wt, immune system status, maturity

  8. Factors to consider when dealing with Toxins: • Solubility • Bioaccumulation • Biomagnification • Persistence • Chemical interactions

  9. Solubility • As water solubility of the toxin goes up, danger goes up! It moves around faster In the body And in our World.

  10. Solubility Oil-Fat soluble toxins Are harder to move around And then once in the body Accumulate in the fat. They can just hang out There and do damage for a Long time…..slowly leaking into the body.

  11. Bioaccumulation and Biomagnification Bioaccumulation Absorption and storage of molecules. Biomagnification The accumulation of toxins low in the tropic levels works it’s way up the food chain.

  12. Persistence • Some toxins degrade rapidly, others hold their chemical structure. • Some things are engineered to hold structure…that’s what we value! It’s bad tho if they are dangerous…and get out in the water…..imagine.

  13. Chemical Interactions Antagonistic reactions • Interference with effects of or break down other chemicals (antioxidants) Additive effects • Effects get emphasized (lead and arsenic) Synergistic effects • One substance exacerbates the effects of another (asbestos and smoking)

  14. Research on lead and arsenic • Asbestos study

  15. How can we minimize the effects? • Metabolic degradation and excretion • Repair mechanisms

  16. Your liver, your filter for toxins

  17. Protection built in to your body! • Cells reproduce quickly to slough off and protect themselves this way. • Irritants (smoking and drinking) reduce the body’s ability to do this effectively. • We were not meant to live as long as we do that’s why we don’t have a resistance to cancer.

  18. How do we measure toxicity? Can you eat too many bananas? Isn’t it the perfect food?

  19. Paracelsus-German scientist “The dose makes the poison”

  20. Animal Testing

  21. More human methods include: • Computer simulations • Cell cultures We still use animal testing despite the options. WHY? Our policies are based on these tests. So politics runs this show.

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