GAC

Granular activated carbon is a highly adsorbent material used to remove contamination from water. Activated carbon has been known as a miracle filter media by many researchers because of its unique ability to remove offensive tastes, odors, color, chlorine and volatile organic chemicals, pesticides and trihalomethanes (a group of suspected carcinogens)

Briefly, activated carbon acts like a sponge, with a large surface area to absorb contaminants in the water. The surface area of one pound of activated carbon is equal to 125 acres. Many scientists believe this is a result of an affinity that these chemicals have for carbon because of Van Der Waal forces. Activated carbon is the preferred treatment and method recommended by the EPA to remove a host of potentially hazardous and possibly carcinogenic chemicals in drinking water. A partial list of chemicals that are reduced or removed by activated carbon are: 


The chart below shows partial contaminants regulated for public water systems by the Safe Drinking Water Act, and the maximum contaminant levels, source, health effects and treatment options for each.
 

Organic

MCL

Source/Industrial occurrence

Health effect

Treatment

Chlorobenzene

0.1

Used as a solvent for paint and metal manufacturing. Also used in insecticides.
Affects nervous system, kidneys and liver.

Activated carbon

CIS-1,2  Dichloroethylene              

0.07

 Used as an industrial solvent in the manufacturing of dyes, perfumes  and lacquers.
Affects liver, and a nervous and circulatory systems. Probable cause of cancer.

Activated carbon

Dibromochloropropane

0.0002

Soil fumigant on soybeans, and cotton. Canceled in 1997
Cancer

Activated carbon

Dichloromethance

0.005

Paint stripper, metal degrease, propellant.
Cancer

Aeration

Dioxin

0.00000003

Chemical production by-product; impurity in herbicides.
Affects lungs, liver and kidney. Probable cause of cancer.

Activated carbon

Epichlorohydrin

0

Used in epoxy resins and coating and in flocculants used in treatment.
Affect nervous system, kidney and liver.

Activated carbon

Ethlbenzene

0.7

Used in the manufacturer of gasoline, insecticides and  asphalt. Probable cause of cancer.

Activated carbon

Ethylene Dibromide

0.00005

Used as a gasoline additive and soil fumigant. Affects nervous system, kidney and liver.

Activated carbon

Monochlorobenzene

0.01

Used in manufacture of pesticides and as a metal cleaner and industrial solvent.

Cancer

Activated carbon

PAHs

0.0002

Coal tar coating, burnings organic matter, volcanoes, fossil fuels.

Cancer

Activated carbon

Phthalate

(di(2-ethylhexyl))

0.006

PVC and other plastics. Affects skin and liver. Causes nausea. Probable cause of cancer.

Activated carbon

Polychlorinated

Biophenyts (PCBs)

0.0005

Used in electrical transformers, Affect nervous system, kidneys and liver.

Activated carbon

Styrene

0.01

Used in manufacturing plastic, resins and foams. Affects nervous system. Probable cause of cancer and anesthesia.

Activated carbon

Tetrachloroethylene

0.005

Used in dry cleaning and as a degreasing agent for metals. Also used for manufacturing rubber, waxes, paints and inks. Affects nervous system, liver and kidneys. Causes narcosis. Irritant to respiratory system.

Activated carbon

Toluene

1

Used in gasoline, paint thinners, lacquers and adhesives.

Cancer

Activated carbon, ozonation

Total Trihalomethanes
(THMs):
Chloroform
Bromoform
Bromodichloromethane
Dibromochloromethane

0.01

Formed when water containing organic matter is treated with chlorine. Affects nervous system and muscles. Probable cause of cancer.

Activated carbon, aeration, ultra filtration (20-90%), RO (20-90%)

1,1 Dichloroethylene

0.007

Used in manufacturing dyes, plastic, perfumes, paints and adhesives Affects kidneys and liver and can cause nausea.

Activated carbon

1,1,2-Trichloroethane

0.005

Solvent in rubber products, chemical production waste. Kidney, liver, nervous system damage

Activated carbon, aeration

1,1,1-Trichloroethane

0.02

Used in manufacturing of pesticides, plastic and metals. Affects nervous system. Causes narcosis and probably cancer.

Activated carbon

1,2 Dichlorobenzene

0.6

Used in the manufacturing of fumigants, insecticides, waxes, resins, rubber and asphalt. Affects lungs, liver and kidneys.

Activated carbon

1,2 Dichloroethane

0.005

Used in the manufacturing of gasoline, paint, varnish, metal degreasers and insecticide fumigants. Damage kidney and liver can cause nausea.

Activated carbon

1,2 Dichloropropane

0.005

Used in insecticide fumigants, dry cleaning fluids and in manufacturing of resins, waxes and petroleum products Affects lungs, liver and kidneys.

Activated carbon

1,2,4-Trichlorobenzene

0.07

Herbicide production; dye carrier. Liver, kidney damage

Activated carbon, aeration

1,4 Dichlorobenzene

0.075

Used in moth repellent, germicides, pesticides and soil fumigants. Affects nervous system, liver and kidneys. Probable cause of cancer.

Activated carbon

Acrytamide

0

Flocculants used in sewage and wastewater treatment. Affect nervous system, probable cause of cancer.

Activated carbon

Adipates

0.4

Synthetic rubber, food packaging, cosmetics. Decreased body weight; liver and testes damage.

Activated carbon, aeration

Benzene

0.005

Used in fuels and as a solvent in manufacturing pharmaceuticals, plastics, pesticides and paints. Often traced to leaking underground storage tanks. Leukemia, anemia and possibly cancer.

Activated carbon

Trans-1,2

Dichloroethylene

0.1

Used as an industrial solvent in the manufacturing of dyes, perfumes, lacquers and rubber. Affects liver, and nervous and circulatory systems.

Activated carbon, ozonation with UV irradiation.

Trichloroethylene

0.1

Used in dry cleaning and as a degreasing agent. Also used for manufacturing rubber, paints, adhesives, resins, oils and fumigants. Irritates body tissue. Affects nervous system. Probable cause of cancer.

Activated carbon

Vinyl Chloride

0.005

Used as a plastic adhesive and refrigerant. The main component of PVC pipe Affects nervous system. Probable cause of cancer.

Activated carbon

Xyienes

0.002

Used in manufacturing paint, ink, petroleum and detergents. Affects nervous system, kidneys, lungs, liver and mucous membranes.

Activated carbon

Pesticides

Aldicarb
Aldicarb Sulfone
Aldicarb Sulfoxide
Carboturan

10

0.003

0.002

0.004

Agricultural insecticide Affects nervous system, respiratory system, kidneys and liver. Probable cause of cancer.

Activated carbon

Chlordane

0.04

Used on rodents, insects, birds. Restricted since 1980. Affects nervous system, respiratory system, kidneys and liver. Probable cause of cancer.

Activated carbon

Endrin

0.0002

Agricultural insecticide. Liver, kidneys, heart damage.

Activated carbon

Heptachlor

0.0004

Agricultural insecticide. Converts to expoxide by soil and water organisms Affects nervous system, respiratory system, kidneys and liver. Probable cause of cancer.

Activated carbon

Heptachlor Expoxide

0.0002

Pesticide production by-product. Affects nervous system, respiratory system, kidneys and liver. Probable cause of cancer.

Activated carbon

Hexachlorobenzene

0.001

Pesticide production by-product. Cancer

Activated carbon

Hexachlorocyclopentadiene

0.05

Agricultural insecticide. Cancer

Activated carbon, aeration

Lindane

0.0002

Agricultural insecticide. Affects nervous system, respiratory system, kidneys and liver. Probable cause of cancer.

Activated carbon

Methoxychlor

0.04

Insecticide used on apples, potatoes, tomatoes. Affects nervous system, respiratory system, kidneys and liver. Probable cause of cancer.

Activated carbon

Oxamyl   Agricultural insecticide. Kidney damage.

Activated carbon

Herbicides

2,4-D
2,4,5-TP (silvex)
Alachlor
Alrazine

0.07

0.05

0.002

0.003

Agricultural  herbicides Affect nervous and reproductive system, respiratory system, kidneys, liver and heart. Causes anesthesia. Probable cause of cancer.

Activated carbon

Dalapon

0.2

Herbicide used on orchards, beans, coffee, lawn, roads and railway. Liver, kidney damage.

Activated carbon

Dinoseb

0.007

Runoff of herbicide from crop and non crop applications. Thyroid, reproduction organ damage.

Activated carbon

Diquat

0.02

Runoff of herbicide on land and aquatic weeds. Liver, kidneys, eye effects.

Activated carbon

Endothall

0.01

Used on crops, land and aquatic weeds. Liver, kidney and gastrointestinal damage.

Activated carbon

Glyphosphate

0.7

Used on grass, weeds, brush Liver, kidney damage

Activated carbon

Pentachlorophenol

0.001

Agricultural herbicide and wood preservative. Affects nervous and reproductive system, respiratory system, kidneys, liver and heart. Causes anesthesia. Probable cause of cancer.

Activated carbon

Picloram

0.5

Used on broadleaf and woody plants. Kidney, liver damage.

Activated carbon

Simazine 0.004 Used on grass sod, some crop, aquatic algae. Cancer.

Activated carbon

The contaminants or other substances removed or reduced by this unit are not necessarily in your water.

Source: Water Technology, Directory Issue / 1995