Common Contaminants in Urban Watersheds - Urban Watersheds: Geology, Contamination, and Sustainable Development - page 247

• Zinc is essential for good health in small amounts. Too little zinc can cause hair
and weight loss. Harmful effects do no usually occur until levels of ingestion
exceed 10-15 times the recommended amount. Effects of overexposure to zinc
include stomach cramps, nausea, and vomiting (ATSDR 2005d).
7.8 Other Contaminants
The remaining contaminants encountered in urban areas span a wide variety of organic
and inorganic compounds and substances. These contaminants include the following:
• Pesticides and herbicides
• Fertilizers such as nitrates, phosphorus, and potassium
• Pharmaceuticals
• Bacteria such as coliform bacteria
• Viruses
• Cyanide
• Asbestos
• Acids
• Bases
• Radioactive compounds
• Dioxins
• Contaminants present only in the air such as
• Greenhouse gases including carbon dioxide, methane, nitrous oxides, and
others
• Carbon monoxide
• Particulates (dust)
• Radon
• Ozone
• Many others
• Emerging contaminants
• And others
7.8.1 Pesticides and Herbicides
Many of the compounds previously discussed including several VOCs, SVOCs, and
arsenic are/were used or are/were ingredients contained in pesticides and herbi-
cides. Simply put, pesticides and herbicides are manufactured to kill things. USEPA
(2009) defines a pesticide as preventing, destroying, repelling, or mitigating any pest.
A herbicide is defined as a substance used to kill unwanted plants commonly referred
to as weeds.