Hazardous Chemicals:

1
Chapter 20

• Hazardous Chemicals
• Pollution and Prevention

2
Toxicology Threshold Levels
The threat of a toxic substance is related to its
concentration and the time of exposure. Chemical
hazards include ignitability, corrosivity,
reactivity, and toxicity
3
Toxicity Sources
Toxic chemicals can be released into the
environment at any point in their life cycle.
4
Toxicity Types

• Heavy Metals lead, mercury, arsenic, cadmium,
  tin, chromium, zinc, copper (affect brain and
  enzyme function)
• Persistent Organic Pollutants petroleum based
  synthetic organics (interact with enzymes and
  do not degrade in the body)

5
Mismanagement

• Deep Well Injection inserting toxins below
  groundwater
• Surface Impoundment keeping toxins in a lined
  surface reservoir until treatment
• Landfills haphazard burying (secure landfill
  is lined to prevent leaching)
• Midnight Dumping abandoning barrels in obscure
  places, leaving them in orphan sites

6
Cleaning Up
Clean up efforts focus on assuring safe drinking
water, remediating groundwater, and taking care
of Superfund sites
7
New Wastes

• Clean Air Act discharge permits for industry
• Clean Water Act Control of Point Source
  pollution
• Resource Conservation and Recovery Act permits
  for landfills, pretreatment of waste to
  non-leachable forms, indefinite tracking of all
  chemical waste

8
New Wastes

• Underground Storage Tanks regulations for
  monitoring and remediation
• Department of Transporation Regulations
  placards for hazardous materials (at left)
• Occupational Safety and Health Act workers
  right to know
• Superfund Amendments and Reauthorization Act
  complete accounting of all industrial chemicals
• Toxic Substances Control Act pre- manufacturin
  g reports for new chemicals

9
New Wastes Overview
10
Future

• Too many regulations?
• Too few regulations?
• Pollution Avoidance
• changing production practices to avoid harmful
  chemicals
• minimizing pollution
• substituting non-hazardous chemical for hazardous
  ones
• reuse of hazardous chemicals instead of dumping

11
Summary

• Toxicology thresholds, sources, metals, POPs
• Mismanagement deep well injection, surface
  impoundment, landfills, midnight dumping
• Clean Up drinking water, groundwater,
  Superfund
• New Wastes Clean Air Act, Clean Water Act,
  Resource Conservation and Recovery Act, UST,
  DOT, OSHA, SARA, TSCA
• The Future too many or too few regulations,
  pollution avoidance