Pesticides
• Let’s look at the reading guide…. What questions do you have???
• Pros and Cons…• Pesticide Treadmill• Circle of Poison
Pesticides – Let‘s Practice
1. An integrated pest-management approach to pest control emphasizes which of the following?
a. Eradication of the pest populationb. Reliance on spraying broad-spectrum pesticidesc. Reduction of crop damage to an economically
tolerable leveld. Use of plant monocultures to simplify sprayinge. Elimination of the use of second-generation
pesticides.
Pesticides – Let’s Practice
2. An insect population in an agriculture field is affected by monthly applications of a pesticide but soon begins to increase in population. A likely cause of the overall increase in the insect population over time isa. An increase in the population of insect predatorsb. An increase in average temperature over the summerc. An increase in soil salinityd. The survival of increase ing numbers of resistant
insects.
Pesticides – Let’s Practice3. Which of the following practices is consistent with the production of organic crops according to the U. S. Department of Agriculture?a. Using sodium nitrate as a fertilizer on green leafy vegetables.b. Using strychnine to prevent buildup of aphid population s in
field cropsc. Using chemicals known as pheromones to disrupt insect
mating cyclesd. Using genetically modified plant varieties that kill insects
that chew their leaves.
Pesticides – Let’s Practice
4. Although the use of DDT was banned in the United States in 1972, a test of the body tissue of an average U.S. resident today would most likely reveal the presence of DDT becausea. DDT is the breakdown product of some newer
pesticides on the marketb. DDT is water solublec. Other countries that export produce to the U.S. still
use DDTd. Many farmers in the U.S. are still using DDT illegally.
Sewage Treatment
Physical and biological treatment
Thirsty Anyone?
Let’s Practice
Which of the following components of a wastewater treatment plant is designed to facilitate the decomposition of organic material by aerobic microorganisms?a. Activated –sludge tankb. Grit-settling tankc. Chlorination tankd. Ultraviolet-light array
Solid Waste
• Facts to know:– Which country generates the most solid waste per
capita?– Which country is second in generating the most
solid waste per capita?– Every man, woman, and child in the U.S. produces
an average of ______ pounds of solid waste per day. – That corresponds to a total of ________tons of
solid waste in the year 2000.
Solid Waste
• Describe the plight of the garbage barge and tugboat Break of Dawn.
• Describe the plight of the Bahamian ship Khian Sea.• Distinguish between municipal solid waste and non-
municipal solid waste.• Which of the two types of solid waste in question
#5 is generated most?• List the composition of municipal solid waste and
the per cent for each category.
Solid Waste
• Identify 4 ways to dispose of solid waste.• What are 4 problems that open dumps have
that sanitary landfills do not have to the same extent.
• What is leachate?• Describe a sanitary landfill.
Solid Waste
• What happens to the waste in a state that has more solid waste than it can handle?
• What are factors that determine the location of an “ideal” sanitary landfill.
• List AND explain four problems with sanitary landfills.• What is NIMBY?• How long does a sanitary landfill have to be monitored
after it is closed?• What are two materials that represent special problems
for sanitary landfills.
Solid Waste
• What is photodegradable?• What is biodegradable • Give two positive things that are accomplished
with solid waste is incinerated (burned).• What is a waste–to-energy incinerator?• Why should batteries, thermostats, and
fluorescent lights be removed before burning?
Solid Waste
• What are the pros and cons of burning paper?• What are the pros and cons of burning
plastics?• What are the pros of burning tires?• What type of air pollutants do incinerators
possibly produce?
HAZADORUS WASTE!!!!
Love’s Canal• Landfill near Niagara Falls, NY• Hooker Chemicals and Plastics Corporation put wastes in
abandoned canal, covered it, deeded 16 acres to Niagara Falls Board of Education in 1953.
• Elementary school built on site; houses built around school
• 1976—chemicals leaking into basements• Environmental emergency declared in 1978• State and federal gov’ts bought >500 contaminated
houses in 1980; 1989 people began to return
HAZADORUS WASTE!!!!• Hazardous (toxic waste) – any discarded chemical that
threatens human health or the environment– 1% of the solid waste in the U.S.– May be solids, liquids, or gases– Includes chemical that are dangerously reactive, corrosive,
explosive or toxic ---- more 700,00 different chemicals are known to exist
– Only 7% of the 3,000 chemicals used in large quantities have been tested for health and environmental effects
– The greatest threat to human health from toxic waste sites comes from drinking water laced with toxic contaminants.
– Table 23.1 --examples
HAZADORUS WASTE!!!!• Dioxins– What are they?– Human sources?– Natural sources?– How are they transferred?– Effects?
HAZADORUS WASTE!!!!• PCB’s– What are they?– Uses?– Effects?– Properties that make them useful in industry?– How are they transferred?– They have been banned by the EPA. Why are they still a
problem?– How can they be destroyed? List 3 ways.
•
HAZADORUS WASTE!!!!• Management of Hazardous Waste– Emergency Response Notification System (ERNS)– Principle of inherent safety – industrial processes
are redesigned to involve less toxic material so that dangerous accidents are prevented
– Resource Conservation and Recovery Act (RCRA)
•
HAZADORUS WASTE!!!!• Instructs EPA to identify which is hazardous
and to provide guidelines and standards to states for hazardous waste management programs.
• Bans hazardous waste from land disposal unless it has been treated to meet EPA’s standards of reduced toxicity.
HAZADORUS WASTE!!!!• Comprehensive Environmental Response.
Compensation, and Liability Act (CERCLA) • Commonly known as the Superfund Act• Established a program to tackle the huge
challenge of cleaning up abandoned and illegal toxic waste sites across the United States.
• •
HAZADORUS WASTE!!!!– A piece of industrial or commercial property that
is abandoned or underused and often environmentally contaminated, and could be considered as a potential site for redevelopment is know as a brownfield.
– Estimates run as high as 400,000 seriously contaminated sites in the United States, not counting military bases and nuclear weapons facilities.
HAZADORUS WASTE!!!!– Superfund National Priorities List – sites that pose the
greatest threat to public health.– Of the 1400 sites on the Superfund National Priority List,
only about 250 have been clean up and 656 other sites have been partially cleaned up.
– There is urgency to clean up these sites because of the growth of cities in rural dump sites.
– Federal government, current land owners, prior owners, anyone who has dumped waste on the site, and anyone who has transported waste to a particular site share in the cost.
HAZADORUS WASTE!!!!• Bioremediation – the use of bacteria and other microorganisms to
break down hazardous waste• Phytoremediation – the use of plants to absorb and accumulate
toxic material from the soil.• Three keys ways to manage current toxic waste
– source reduction• environmental chemistry – green chemistry
– conversion to less hazardous materials• using high heat
– long-term storage• uses several layers of clay and high density plastic liners at the
bottom of the landfill
HAZADORUS WASTE!!!!• International waste management – hazardous waste is transported to developing countries.– Basel Convention (1992)– formed to restrict the
international transport of hazardous waste.• Integrated waste management – The 3 “R”• Reduce, Reuse, Recycle• Throw- away society– high input society– voluntary simplicity
Let’s Practice1.Most municipal solid waste in the United States is disposed of ina. The oceansb. Sanitary landfillsc. Open dumpsd. Abandoned mines