Heavy Metal Toxicity earthref orgSCC Scripps Classroom Connection

Heavy Metal Toxicity earthref. org/SCC Scripps Classroom Connection

Defining Water Pollution • Water pollution: degradation of water quality • Water Quality My Be Evaluated Based on: 1. Use 2. Change from Norm 3. Drinking Quality earthref. org/SCC Polluted water in India Scripps Classroom Connection

Water Uses Agriculture Industrial Processes Power Generation Home Use (Domestic) earthref. org/SCC Scripps Classroom Connection

Sources of Pollutants to Water Direct Sources Runoff Leaks Seepage into groundwater Air transport Indirect Sources Population size- leads to more pollution overall earthref. org/SCC Scripps Classroom Connection

Categories of Pollutants earthref. org/SCC Scripps Classroom Connection

Water Requirements for Home Use Water must be free from: Fine sediment Insecticides Pesticides Pathogens Heavy metals Should also taste good, be odorless, not damage plumbing earthref. org/SCC Scripps Classroom Connection

Heavy Metals in the Environment “Heavy” metals: high atomic weight Human released Natural earthref. org/SCC Scripps Classroom Connection

Effects Of Metals on Health Direct Effects Physiological- metals can inhibit basic body functions Indirect Effects Stored in tissues over time- initial dose might be ok, but can accumulate over time (bioaccumulation) Example: Mercury “Mad hatter”- mercury used in hat making earthref. org/SCC Scripps Classroom Connection

Health Effects from Toxic Metals: Minamata, Japan Mercury release from 1932 - 1968. Bioaccumulation in shellfish 2, 265 victims were reported and 1, 784 of them had died Mercury poisoning earthref. org/SCC Scripps Classroom Connection

Heavy Metal Uptake Pathways Humans Consumers Plants Phytoplankton Water earthref. org/SCC LAND WATER Humans Metals Soil Metals Scripps Classroom Connection

Example: Lead (Pb) Contamination Mt. Pleasant, Michigan: contaminated with lead (4 x EPA standards). The highest concentrations were found near homes built before 1930. Why? Leaded paint and gasoline Seep into groundwater earthref. org/SCC Scripps Classroom Connection

Example: Copper in San Diego Bay Copper levels in San Diego Bay are much higher than in neighboring Mission Bay. Why? San Diego Bay earthref. org/SCC Mission Bay Scripps Classroom Connection

Sources of Copper to San Diego Bay Anti-fouling paint on boat hulls Run-off- brake pads, storm water earthref. org/SCC Scripps Classroom Connection

The Effects of Copper in San Diego Bay Damaging to plant and fish life Fish, mussels, kelp Ultimately un-healthy for humans Recreational activities in the bay- such as fishing meso. spawar. navy. mil earthref. org/SCC Scripps Classroom Connection

Studying the Effects of Anti-fouling Paint on Cu Concentrations in San Diego Bay Copper regulations Anti-fouling paint Why so much copper? Type of paint Boat cleaning methods earthref. org/SCC Scripps Classroom Connection

Copper Leach Rates from Anti-fouling Paint Copper Concentration (µg/L) 200 180 160 Control 140 Scrubbed 120 100 80 60 40 20 0 0 earthref. org/SCC 10 20 30 40 Time (min) 50 60 70 Scripps Classroom Connection

Conclusions Water pollution: degradation of water quality from its original state Depends on use Heavy metals: harmful pollutants Dangerous to human health Toxic to marine life Heavy metal contamination Recent decline Some remain a problem: copper earthref. org/SCC Scripps Classroom Connection