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There is an old Mexican Proverb that says:

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What is pollution ?

Biohazard - bio-damage: How do we monitor?

Sensitive species vs. Community Response

Food Chain/Ecological Structure (xenobiotics - foreign to living tissue)

Bioaccumulation (in single organisms)

Concentration/enrichment factor (biota/water),

Biomagnification in several levels of food-chain.

Eutrophication - BOD, COD

Human Effects (e.g., cancer, birth defects, endocrine disruption, respiratory)

Soap Opera

Sources and Pathways (Recall concept of Reservoir, Residence Time, etc.)

Point, non-point, primary, secondary (Table 30.2, Libby), synergism

Chemical Transformation

Chemical Equilibrium (Ions and Complexes)

A Pollutant may be transformed to less harmful or more harmful forms

Toxicology - damage to biological systems.

Biochemical susbtances (proteins, carbohydrates, lipids) in cells are reactants, products or catalysts of cell function.

Proteins are large polymers of amino acids linked by peptide bonds (this bonding determine protein identity). Secondary and tertiary bonds (hydrogen, electrostatic, disulfide bonds) allow secondary and tertiary structures leading to folds and helixes. With phosphate and pentose sugar (deoxyribose) form DNA.

Carbohydrates -sugars (CH2O). Lipids - fat, oil, waxes, steranes.

Enzymes are proteins whose secondary and tertiary structures enable them to function as catalysts (they have active sites that bind substrate to the enzyme) of very specific reaction needed for proper cell function.

What are we concerned about?

• Toxins can destroy the effectiveness of enzymes (denature the active site or block the site using compunds that have similar structure as substrate). Same damage can be done to co-enzymes.

• The genetic code of DNA is contained in so-called base templates (sequence of amines in the DNA structure). Mutagens, tertogens (birth defects) could alter that base sequence.

• Endocrine disruptors.

Maximum Contaminant Level Goal (MCLG)

• Zero (0) for all carcinogens
• Non-enforceable goal set to prevent known or anticipated health effects with a WIDE margin of safety.

Maximum Contaminant Level (MCL) Table 1.5, Fetter

• Enforceable limit set as close as possible to MCLG, but consider water treatment technology and cost.
• Primary – health risk
• Secondary – aesthetics

Related Parameters: BOD (O₂ consumption of microbially mediated rxn – 5 day consumption), COD (O₂ consumption during dichromate oxidation)

Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) <–> "Superfund"

• If cancer risk is 1 in 1,000,000 (10^-6) or lower, no clean-up required.
• If cancer risk is 100 in 1,000,000 (10^-4) or higher, clean-up required.
• If cancer risk is between 10^-6 and 10^-4 clean-up determined by State.

Categories of Contaminant Sources

Septic systems are a means of disposal of household wastewater for homes that are connected to a public sewer system. Household sewage is a combination of wastewater from toilets, showers, tubs, sinks, washing machings, dishwashers and garbage disposals. The toilet is the largest source of wastewater in most households.

About 60 % of all land applications are agricultural.

Less of a problem because of natural vegetation retard transport.

Underground Storage Tanks (USTs)

The definition given by the EPA of an UST is any tank and associated underground piping that has at least 10% of its volume underground.

WHAT IS THE COMPOSITION OF A LANDFILL?

• the natural hydrogeologic setting,
• a bottom liner,
• a leachate collection system,
• and a cover.

• Bacteria
• All human feces are comprised of a significant portion of bacteria, about 25%.

• Bacteria can produce acids that can "eat" away the concrete pipe, and cause other damage.