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General Compounds particularly associated with industrial areas include metals (see metal monitoring in water and sediments), Polychlorinated biphenols (PCB), Polyaromatic Hydrocarbons (PAH), Organochlorines (OC), and Organophosphates (OP). Polychlorinated biphenyls, PCBs - were manufactured by one company - Monsanto Chemical - starting in the 1930s. They were promoted as a nearly indestructible replacement for hydraulic oil, pump oil, and the oil bath for electrical transformers and capacitors. It was known even in the 1930s, when production began, that they were extremely toxic. PCB oil was used to transfer heat. Transformers used for transmission of electricity are ubiquitous, and millions of gallons of PCB oil were used to transfer heat from the transformer coils to the heat sink - the metal can surrounding the coils and holding the oil. Inevitably, both during manufacture of the transformers, in auto and weather accidents, and in the disposal of defective or damaged transformers, millions of gallons of PCB oil has leaked out and found its way into waterways. PCBs are mixtures of synthetic organic chemicals with the same basic chemical structure and similar physical properties ranging from oily liquids to waxy solids. Due to their non-flammability, chemical stability, high boiling point and electrical insulating properties, PCBs were used in hundreds of industrial and commercial applications including electrical, heat transfer, and hydraulic equipment; as plasticizers in paints, plastics and rubber products; in pigments, dyes and carbonless copy paper and many other applications. Between the 1930s and the 1970s, when PCB manufacture was halted, over 3 billion pounds were manufactured. It is estimated that approximately 1% of this has leaked into the environment. PCB molecules are nearly indestructible, and evaporate and migrate towards the poles. When PCBs are burned, even more toxic dioxins and furans are formed. It is believed that PCBs and dioxins are the major cause of reduction of sperm count in human males worldwide. PCB fact sheet http://www.oag.state.ny.us/pcb/pcb.html Risk assessment for Dioxins and PCBs http://www.ktl.fi/dioxin/general.html#burning Organochlorines (OCs) Definitions http://www.r1.fws.gov/ecoservices/envicon/pim/reports/contaminantinfo/contaminants.html General information on OCs (New Zealand) http://www.mfe.govt.nz/issues/hazardous/contaminated/organochlorines.html The presence of dioxins (a class of OCs) in the environment has attracted considerable attention in recent years from the public and scientific community. These compounds are not intentionally produced, but a variety of industrial and combustion sources have been identified. The toxic nature of dioxins at extremely low concentrations poses a very difficult problem for scientists and regulators to address. Typical analytical detection limits for water samples collected using conventional sampling methods ranges from one to ten parts per quadrillion (ppq). Polycyclic Aromatic Hydrocarbons (PAHs) Also known as: Polynuclear Aromatic Hydrocarbons, PNA, Polyaromatic
Hydrocarbons PAHs are a group of approximately 10,000 compounds, a few of which are listed above. Most PAHs in the environment are from incomplete burning of carbon-containing materials like oil, wood, garbage or coal. Many useful products such as mothballs, blacktop, and creosote wood preservatives contain PAHs. They are also found at low concentrations in some special-purpose skin creams and anti-dandruff shampoos that contain coal tars. Automobile exhaust, industrial emissions and smoke from burning wood, charcoal and tobacco contain high levels of PAHs. In general, more PAHs form when materials burn at low temperatures, such as in wood fires or cigarettes. High-temperature furnaces produce fewer PAHs. Fires can form fine PAH particles. They bind to ash particles and can move long distances through the air. Some PAHs can dissolve in water. PAHs can enter groundwater from ash, tar, or creosote that is improperly disposed in landfills. US EPA Fact Sheet – PAH Compound Illinois EPA - PAH background study (Family of compounds) Organophosphates (OPs) General information on organophosphates US – Toxic chemicals and health UK – Pesticides News Total Environment Centre Media Release Call to ban toxic organophosphates
A variety of sources indicate Collect bottom water column samples three or four times during
the year to determine water column concentrations for different
seasonal flow regimes (e.g., Summer low flow, Spring high flow periods).
Summer sampling should be concurrent with sediment and biota sampling.
In addition to dissolved and particulate concentrations of organic
contaminants (PCBs, PAHs, OCs, OPs), measure Dissolved Organic Carbon
(DOC), Particulate Organic Carbon, suspended solids, pH, and salinity. Standard Methods for the Examination of Water and Wastewater (20th
Edition) Published by the American Public Health Association, Pesticide Residue Test Kit US EPA Test Methods Costs Approx. $100 per water sample Case study Managing pesticides in NSW CSIRO Sewage Sludge Central and North Western NSW Pesticides Study US Geologic Survey – PAHs in sediments People contacts Australian Pesticides and Veterinary Medicines Authority http://www.apvma.gov.au/index.html Organisation contacts NSW EPA – How pesticides work Advanced references Stormwater detention ponds (Canada) Dioxin in the US US Geologic Survey – Organic compounds in groundwater |
Internal Links Constructed Wetland Monitoring Desktop Monitoring Using Satellite Data Fish Monitoring for Water Quality Gross Pollutant Trap Monitoring |
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