Filter A: Compressed Activated Carbon
What does active carbon filters remove and reduce?
Activated carbon can be effective in reducing hundreds of substances including contaminants and other chemicals from the tap water. However, the most cited studies by EPA and NSF claim effective removal of between 60-80 chemicals, effective reduction of another 30 and moderate reduction for 22.
According to EPA (the Environmental Protection Agency in the United States) Activated Carbon is the only filter technology recommended to remove
- all 32 identified organic contaminants including THMs (by-products from chlorine).
- all 14 listed pesticides (this includes nitrates as well as pesticides such as glyphosate also referred to as roundup)
- the 12 most common herbicides.
These are the specific contaminants and other chemicals that charcoal filters remove.
Most public tap water in Europe and North America is highly regulated, tested and certified for drinking. However, to make it safe, chlorine is added which may make it taste and smell bad. Activated Carbon filters are excellent at removing chlorine and related poor taste and odor. High quality activated carbon filters can remove 95% or more of the free chlorine.
Chlorine should not be confused with Chloride which is a mineral combined by sodium and calcium. Chloride may actually increase slightly when the water is filtered with activated carbon.
The most common concern about tap water is by-products (VOCs) from chlorine such as THMs that are identified as potentially cancerous. Activated carbon is more effective than any other filter technology in removing these. According to EPA it removes the 32 most common chlorine by-products. The most common measured in tap water reports is total THMs.
Chloride is a natural mineral that helps maintain proper blood volume, blood pressure, and pH of body fluids. However, excessive Chloride in water may cause a salty taste. Chloride is a natural component of tap water without any negative health aspects. It’s a part of the chlorination process of drinking water from harmful bacteria and viruses. It does not need to be filtered or removed but activated carbon typically reduces chloride by 50-70%. In exceptional cases chloride may actually increase.
Pesticides are substances that are meant to control pests, including weeds that end up in groundwater, lakes, rivers, the oceans and sometimes tap water despite treatment. Activated Carbon is tested to remove the 14 most common pesticides including Chlordane, Chlordecone (CLD/Kepone), Glyphosate (Round-up), Heptachlor, and Lindane. This also includes Nitrate (se below).
Herbicides also commonly known as weedkillers, are substances used to control unwanted plants. Activated Carbon is tested to remove 12 of the most common herbicides including 2,4-D and Atrazine.
Nitrate is one of the most important compounds for plants. It is a rich source of Nitrogen, which is essential for plant growth. Nitrate has no known harm-effect on adults unless it’s extremely high amounts. However, excessive Nitrate in water can cause Methemoglobinemia, or “blue baby” disease (Lack of oxygen).
Nitrate in tap water primarily originates from fertilizers, septic systems, and manure storage or spreading operations. Activated carbon typically reduces nitrate by 50-70% depending on the quality of the filter.
PFOS is a synthetic chemical used in e.g. fire-fighting foam, metal plating and stain repellents. Over the years it has ended up in the environment and drinking water sources with a couple of major incidents in North America and Europe. According to a 2002 study by the Environmental Directorate of the OECD “PFOS is persistent, bioaccumulative and toxic to mammalian species.” Activated Carbon has been found to effectively remove PFOS including PFAS, PFOA and PFNA.
Phosphate, like nitrate, is essential for plant growth. Phosphate is a strong corrosion inhibitor. High concentration of Phosphate has not shown any health risks for humans. Public water systems (PWSs) commonly add phosphates to the drinking water to prevent the leaching of lead and copper from pipes and fixtures. High quality charcoal filters typically remove 70-90% of phosphates.
Lithium occurs naturally in drinking water. Although it exists at very low rate, Lithium is actually an antidepressant component. It has shown no harmful effects on the human body. Lithium can be found in continental brine water, geothermal waters, and oil-gas field brines. Charcoal filters such as TAPP reduce 70-90% of this element.
The ubiquitous use of pharmaceuticals has resulted in a relatively continuous discharge of pharmaceuticals and their metabolites into wastewater. Current observations suggest that it is very unlikely that exposure to very low levels of pharmaceuticals in drinking-water would result in appreciable adverse risks to human health, as concentrations of pharmaceuticals detected in drinking-water are several orders of magnitude lower than the minimum therapeutic dose. Pharmaceuticals may be released into water sources in the effluents from poorly controlled manufacturing or production facilities, primarily those associated with generic medicines. High quality carbon block filters remove 95% of pharmaceuticals.
Microplastics are the result of plastic waste in different kinds of sources. The precise effect of microplastics on human health is difficult to determine for a variety of reasons. There are many different types of plastics, as well as different chemical additives that may or may not be present. When plastic waste enters waterways, it does not degrade as natural materials do. Instead, exposure to the suns rays, reaction to oxygen, and degradation from physical elements such as waves and sand cause plastic debris to break down into tiny pieces. The smallest microplastics identified in public reports is 2.6 micron. A 2 micron carbon block removes all microplastics larger than than 2-microns.