I. Air Pollution – Components

F. Lead (Pb)1. Sources

• Formerly motor vehicles• Transition to unleaded gasoline virtually

eliminated this source• Industrial plants

• Smelters• Battery manufacturers

• Human exposure mostly through inhalation of lead in air and dust• Food• Paint• Water

I. Air Pollution – Components

F. Lead (Pb)2. Effects

• Not readily excreted by body• Accumulates in tissues, especially kidneys, liver,

nervous system, bones• Health

• Anemia• Kidney disease• Reproductive disorders• Neurological problems (seizures, mental

retardation, behavioral disorders)• Birth defects (CNS damage, retarded growth)• High blood pressure heart disease

• Environment• Deposition on leaves of plants is hazardous to

grazing animals and humans (ingestion of meat)

Lead1990-2010: Pb emissions down 60%

Comparison of growth measures and emissions, 1990-2010

**Ozone and PM2.5 shown relative to standards revised in 2008 and 2006, respectively**

Comparison of National Levels of the Six Criteria Pollutants to the Most Recent NAAQS, 1990-2010

Number of People Living in Counties with Air Quality Concentrations Above the Level of the NAAQS in 2010

www.epa.gov/air/airtrends/2011/index.html

Number of Days on Which Air Quality Index (AQI) Values Were Greater than 100 During 2002-2010

www.epa.gov/air/airtrends/2011/index.html

II. Air Pollution – Regulation & Legislation

• History – “Pollution is the price of progress”A. Air Quality Act (1967)

• Authorized secretary of HEW to establish air quality regions

• States given responsibility of adopting and enforcing pollution control standards

• Controversial – Air pollution doesn’t stop at regional boundaries

• Failure – Only a few regions were established, and no state had established a full pollution control program

B. Clean Air Act (1970)• Established National Ambient Air Quality Standards

(NAAQS)• Typically annual average concentration or daily

maximum concentration• Established statutory deadlines for compliance• EPA (federal agency) responsible for recommending

policy to Congress and monitoring/enforcing policy

II. Air Pollution – Regulation & Legislation

B. Clean Air Act (1970)• Local enforcement left to state governments

• States allowed to have more stringent pollution standards than EPA

• “Command and Control”• EPA established standards and technology used to

achieve standards• Non-compliance heavy fines

C. Clean Air Act Amendments (1990)• Market-based approach to achieving NAAQS

• “Cap and Trade” system• Examples

• Time frames for compliance based on designation of “nonattainment areas” (marginal to extreme)

• Tailored to specific situations• Established possibility of emissions trading

• Allows economic and technological flexibility

III. Water Pollution – Sources and Effects

A. Background• Oceans – 97% of world’s water• Ice & permanent snow – 2%• Ground water – 0.6%

• Provides drinking water for 50% of people in US• Sources of water pollution tend to be less centralized and

identifiable, compared to sources of air pollution• Relatively few pollutants characterized

B. Sources1. Pollution

a. Point sources• Discharge directly into receiving waters• Easier to characterize and regulate than NPS’s

b. Non-point sources• Pollutants from diffuse sources• May vary regionally and seasonally• Ex – Chloride from salting streets in winter• May be difficult to distinguish natural from anthropogenic

effects