Identifying Water Contaminants

The scope of water contamination increases with additional testing, studies and publications on water quality in Canada and across the globe. Some water contaminants are widely known and others are not mainstream. While detailed, this is not a comprehensive summary of all potential water contaminants, as there are too many to possibly list, with new contaminants emerging that are not fully comprehensible with current research.

To assist with understanding levels and testing results, the recommended Canadian Drinking Water Regulations are shown for each contaminant as a guideline for drinking water quality. This document is meant to be a summary of the more common contaminants, their potential effects and what is generally considered acceptable methods to properly treat each contaminant. 

Can be naturally produced by the oxidation of nitrogen by microorganisms and as a byproduct of lightning strikes. Can be a product of discharges from industrial processes and motor vehicles, or a chemical found in agricultural and lawn fertilizer. Nitrates are formed when waste materials such as manure or septic system effluent decompose. High levels can be attributed to thyroid dysfunction, certain types of cancer, baby blue syndrome and birth defects. 

Caused by atmospheric deposition and stream bank erosion, urban runoff, non-agricultural rural runoff and seepage from individual sewage treatment systems. Too much phosphorus can cause increased growth of algae and large aquatic plants, which can result in eutrophication. High levels of phosphorus can also lead to algae blooms that produce algal toxins such as blue green algae.

This contaminant is very soluble in water. The contamination source is from road salt, septic systems, landfill leaching, natural deposits, animal waste or other wastes. Chloride is important as a measure of human influence on a water source. 

TREATMENT: Reverse Osmosis, Distillation

Originates in water supplies from natural sources, sewage, urban and agricultural runoff and industrial wastewater. They’re composed of inorganic salts and small amounts of organic matter which are dissolved in water. They can be from salts used for road de-icing. 

TDS can be used as a benchmark for changing patterns in a water source or time indicating human influence on a water source. Surface water under the influence of groundwater is more likely to have elevated levels.

TREATMENT: Reverse Osmosis, Distillation

Heath Canada has issued an aesthetic objective of <500 mg/L for total dissolved solids. Since 1 GPG of hardness is equal to 17.1 ppm, then if you live in an area with high water hardness levels (ie >30gpg) it is likely that your total dissolved solids level will exceed the recommended guideline for the Canadian drinking water standards. 

Escherichia coli (E. coli) is a species of bacteria that is naturally found in the intestinal system of humans and animals. It is present in feces in high numbers and can be easily measured in water, which makes it a useful indicator of fecal contamination within water sources. It can enter surface and groundwater water through sewage and industrial effluents, septic systems, leaking sanitary sewers, runoff from agricultural, and urban and natural areas. This bacteria can cause gastrointestinal illness, skin, ear, respiratory, eye, neurologic, and wound infections. The most commonly reported symptoms are stomach cramps, diarrhea, nausea, vomiting, and low-grade fever.

TREATMENT: Chlorination, Ultra Violet Disinfection

Viruses that can multiply in the gastrointestinal tract of humans or animals are known as enteric viruses. According to new studies it has been proven that these viruses exist in water with more than 200 variations. Of these 200, approximately 140 are currently known to infect humans. They have been found throughout surface and groundwater supplies according to a recent Health Canada publication. Approximately 70% of Canadian regional aquifers that provide drinking water to citizens are fractured bedrock and therefore susceptible to surface water runoff and septic effluent leaching. To this point, studies have reported that 35% to 78% of private wells with septic systems nearby have shown viral detection in water sources.

TREATMENT: Chlorination, Ultra Violet Disinfection

As the name suggests, microplastics are tiny pieces of plastic that are ubiquitous in the environment and have been detected in a broad range of concentrations in marine water, wastewater, fresh water, food, air and drinking-water, both bottled and from the tap. 

They are tiny particles or fibres of plastic 5 mm or less in diameter, which is down to a microscopic level. Mostly plastic based, microfibres are tiny synthetic fibres from garments, cleaning cloths, and other consumer products.                                                                             

TREATMENT: Reverse Osmosis, Distillation, Nano Filtration

Without proper testing it is not possible to know if any of these contaminants are present in a water supply. Further complicating this issue, most of the testing requires an accredited laboratory to perform the testing to ensure proper results.

When present in drinking water, arsenic can lead to nerve, heart, skin, and blood vessel damage. Inorganic arsenic is naturally present at high levels in groundwater throughout many countries. Research has established that consuming water that is contaminated with arsenic increases the risk of skin cancer and several internal cancers such as lung, bladder, and kidney cancer, as well as cardiovascular disease and other adverse outcomes.

TREATMENT: Reverse Osmosis, Distillation, Specialized Medias

Lead is a toxic heavy metal that was, for many years, widely used in a variety of products. These included cosmetics, paint, solder, pipes, valves, fittings and plumbing. Canadian municipalities began phasing out the use of lead in service piping to properties in the 1960's. The National Plumbing Code permitted the use of lead until 1975 and lead solder until 1986. 

Lead is toxic and can be harmful to human health, even in small amounts. It can pose a significant public health risk if ingested or dissolved in drinking water.

Per- and polyfluoroalkyl substances (PFAS) are a group of over 4700 human made synthetics, commonly known as “forever chemicals” due to their persistence in the environment and collection in living tissues. With origins dating back to the 1940’s, this group of chemicals has been used in a wide variety of industrial and consumer products such as adhesives, cleaning products, nonstick pans, food wrapping containers, clothing, electronics, cosmetics and fire fighting foams. They are also used in water, stain and oil repellent coatings for paper products and fabric. 

Recent studies have identified PFAS in surface water, groundwater, wastewater and rainwater sources in Canada. 

Contaminants of Emerging Concern (CEC’s) are synthetic or naturally occurring chemicals as well as any microorganisms that are not commonly monitored but have potential to cause adverse ecological and/or human health effects. They consist of, but are not limited to: pesticides, pharmaceuticals, industrial chemicals, cleaning detergents and personal care products; all of which are consistently found in various important water sources. 

These include groundwater, surface water, municipal wastewater, drinking water, and a variety of food sources. Medications, antibiotics, hormones, endocrine-disrupting compounds and other pharmaceutical compounds (anti inflammatory, antidiabetic, and antiepileptic drugs) are also classified as CEC’s.

TREATMENT: Reverse Osmosis, Distillation

Understanding the full scope of water contamination for any water sources is complex, and adding to the confusion  is the varying nature of water sources and the origins of incoming contaminants. Proper laboratory testing for individual contaminants is the only way to accurately identify potentially harmful levels that may be present.

Not all treatment equipment removes every contaminant from water. Consult a water treatment professional for recommendations on the proper equipment to treat the water within your home, cottage or business.