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How are Chemicals Getting in My Water?

How are the Chemicals Getting in my Water?

Chemicals from water treatment and distribution reach drinking water by the most direct route. They fall into three broad categories:

  1. Substances resulting from the addition of chemicals used in the treatment process for coagulation and disinfection – these chemicals are intentionally added and can give rise to residues or by-products.
  2. Disinfectants that are deliberately added to maintain a residual effect in distribution, usually to the tap – these chemicals may also give rise to by-products
  3. Substances that leach from materials used in distribution or plumbing, or that arise from the corrosion products of pipes.

Most chemicals that end up in our water are a result of being directly added or from runoff. It is important that water supply agencies properly manage any chemicals that they use. In many cases, the best method of control is through management practices, such as optimization of the treatment process, and regulation of materials and chemicals that come into contact with drinking water, rather than through monitoring and chemical analysis.

water treatment plant chemicals

Water Treatment Plants are the source of the majority of chemicals that are added to our water

What Kind of Chemicals are used in Water Treatment?

Disinfectants and disinfection by-products are the categories of chemicals generally added to treat water. Coagulants, Algaecide, and nutritional additives like fluoride are also chemicals that can be added to your water.

The three chemicals most commonly used as primary disinfectants are chlorine, chlorine dioxide and ozone. Monochloramine, usually referred to as chloramine, is used as a residual disinfectant for distribution.


Chlorine is the most widely used primary disinfectant and is also often used to provide residual disinfection in the distribution system. Monitoring the level of chlorine in drinking water entering a distribution system is normally considered to be a high priority (if it is possible), because points in the distribution system is sometimes used to check that there is not an excessive chlorine demand in distribution that may indicate other problems in the system, such as ingress of contamination. Chlorine reacts with naturally occurring organic matter in raw water to form a range of unwanted by-products. Guideline values have been established for a number of these byproducts. The compounds most widely considered as representatives of chlorination byproducts for setting standards and monitoring are the trihalomethanes (THMs) which include chloroform, bromodichloromethane, chlorodibromomethane, and bromoform. Haloacetic acids (HAAs), such as monochloroacetate, dichloroacetate, and trichloroacetate, can also be formed as the result of a reaction of chlorine with organic matter contained in raw water. Some countries monitor HAAs as well as THMs, but HAAs are much more difficult and expensive to analyze than THMs. THMs and HAAs continue to develop within the distribution system; thus, monitoring can be complex. Optimizing coagulation and filtration is most important in helping to remove the precursors of these by-products and will, in turn, reduce the formation of THMs, HAAs and other unwanted by-products. To ensure the microbial safety of drinking water, disinfection should never be compromised in trying to meet guidelines for any disinfection by-products.

Chlorine dioxide uses in Water Systems:

Chlorine dioxide breaks down to leave the inorganic chemicals chlorite and chlorate. These are best managed by controlling the dose of chlorine dioxide applied to the water. Chlorite can also be found in hypochlorite solution that has been allowed to age. There is no guideline value for chlorate because of limited data on its toxicology, but this chemical is less toxic than chlorite and is present at lower concentrations. Controlling chlorite will generally also adequately control chlorate.

What is Ozone?

Ozone, used as a primary disinfectant, unfortunately, it cannot be monitored in drinking water because it leaves no residual trace. Ozonation in the presence of inorganic bromide, which can occur naturally in raw water, can give rise to low concentrations of bromate. The analysis of bromate is difficult and expensive because several other inorganic substances that interfere with the analysis may be present. It is considered, therefore, that bromate monitoring is a low priority, and that management should instead involve controlling the conditions of ozonation.

What are Monochloramines?

Monochloramine, used as a residual disinfectant for distribution, is usually formed from the reaction of chlorine with ammonia. Careful control of monochloramine formation in water treatment is important to avoid the formation of di- and trichloramine's because these can cause unacceptable tastes and odors. The formation of nitrite because of microbial activity in biofilms in the distribution system is a possibility when monochloramine is used as a residual disinfectant, particularly if ammonia levels are not sufficiently controlled.

Is Algaecide Harmful to Drink or Swim in?

Generally, Algaecide is made from copper sulfate. It is considered safe for humans but can be toxic for fish and some domestic animals. So obviously discharging this stuff into the environment is not good. They have also been using Hydrogen Peroxide as a method to control algae but its not as effective as copper sulfate.

What are Coagulants and what do they do?

Coagulation and flocculation are important barriers to microbiological contaminants and are key processes for reducing naturally occurring organic matter and turbidity, which can seriously affect the efficiency of disinfection. Chemicals used as coagulants in drinking-water treatment include aluminum and iron salts, such as aluminum sulfate, polyaluminum chloride, or ferric sulfate. No health-based guideline values have been set for aluminum and iron because neither is of significance to health when used under normal circumstances in water treatment. However, both substances can give rise to problems of discoloration and deposition of sediment in distribution if present in excessive amounts. The concentrations in drinking water above which problems are likely to occur are 0.3 mg/l for iron and 0.2 mg/l for aluminum. This concentration of aluminum should be achievable by any water treatment works, but a well-run large treatment works should be able to achieve a routine average residual value of 0.1 mg/l. The best management strategy for both aluminum and iron when used in treatment is to ensure that coagulation is optimized to prevent excessive amounts remaining in the drinking water. Sometimes organic polymers, known as coagulant aids, are used to assist with coagulation. These polymers may contain residual acrylamide or epichlorohydrin monomers. Monitoring for these chemicals in drinking water is not normally appropriate, because measurement in water is very difficult. Instead, these chemicals are managed by specifying a maximum amount of residual monomer in the polymer and a maximum concentration of polymer that can be added to the treatment process. The World Health Organization Guidelines for Drinking-water Quality give additional guidance on the approval and control of chemicals and materials in contact with drinking water. 

chemicals in water

Chemicals should not be added to our drinking water when there are better solutions to the problems chemicals address.

What Other Chemicals and Materials are Used in Water Treatment?

Several other chemicals may be added to the treatment. These include substances such as sodium hydroxide for adjusting pH and, in certain circumstances, chemicals for the fluoridation of drinking water. In all cases, it is appropriate to specify the quality of the chemicals added so that the final water does not contain unacceptable concentrations of unwanted contaminants. Ensuring that chemicals used are of appropriate quality is generally best managed by product specification rather than by monitoring drinking water. The World Health Organization) has a section on approval and control of chemicals and materials for use in contact with drinking water that guides product specification. Ion-exchange resins and more advanced treatment processes based on membranes are increasingly used in drinking-water treatment. It is possible that chemicals can leach from the materials used in the manufacture of these systems; therefore, these too should be managed by appropriate product and materials specifications.

Chemicals that Treat Scale in Water Systems?

Phosphoric Acid

Phosphoric Acid is sold under several different brand names but is always marketed as a Water Treatment Chemical. Phosphate water treatment chemicals are primarily used as an integral part of corrosion control processes used by municipal drinking water authorities or other industries to purify and improve the quality of drinking water as it is distributed to the public. Controlling staining (red water caused by iron-based impurities and black water caused by manganese-based impurities), controlling copper, and controlling lead release to the public is the primary application of phosphate-based products. The main benefits of using phosphate products are the following:

1. Extends the operating life of the water distribution system by reducing corrosion and scale formation.

2. Eliminates and/or minimizes the presence of lead, copper, iron, and manganese impurities in municipal drinking water.

3. Increases the water quality by preventing rusty and dirty water, discoloration, staining, mineral buildup, or leaching of heavy metals.

Phosphates are also generally consumed by the public in multiple products. It is found in toothpaste, cola-based products, cheeses, as well as leavening agents in baking. Phosphoric acid can be found in many popular soft drinks. The warning labels on most of these products should be a cause for alarm. With this chemical already being consumed in the above-mentioned products. I would prefer it not be added to my water considering the following paragraph.

What Chemicals are Used to Treat Scale and Corrosion in Water Systems?

Phosphate and Orthophosphate products are generally the go-to for dealing with scale chemically. Phosphoric acid is clear, homogeneous acidic solution.

Note that it has a markedly corrosive action on all body tissues and should be handled with care. Even dilute solutions may be acidic and may have a destructive effect on tissue after prolonged contact.

Inhalation of mists can cause damage to the upper respiratory tract. Ingestion can cause sore throat, abdominal pain, nausea, and severe burns of the mouth, throat, and stomach. The liquid products have a specific gravity of about 1.2-1.6 g/ml. They are of acidic pH (is chemical is commonly used to treat scale and corrosion issues in water systems.

Muriatic Acid is another approved chemical used to treat scale in drinking water systems. You might be more familiar with its other name Hydrochloric acid. This is a very dangerous substance and its being used in our drinking water systems. Hydrochloric acid is corrosive to the eyes, skin, and mucous membranes. Acute (short-term) inhalation exposure may cause eye, nose, and respiratory tract irritation and inflammation and pulmonary edema in humans. Another chemical that we should not be drinking or discharging into the environment. Especially when there are superior methods of treating scale in domestic water systems that don’t require the use of chemicals.

What are the Health and Environmental Effects of Descaling Chemicals?

The health effects of phosphate and orthophosphate products and other acid-based products are mainly due to their corrosive properties. They are corrosive to skin, eyes, or respiratory tract. Contact with skin may cause redness, pain, and severe skin burns. Contact with eyes may cause redness, pain, blurred vision, eye burns, and permanent eye damage. In applications where dust, vapors, or mist are created, inhalation may irritate the respiratory tract. Symptoms may include coughing and shortness of breath. Ingestion may cause sore throat, abdominal pain, nausea, and severe burns of the mouth, throat, and stomach. Severe exposures can lead to shock, circulatory collapse, and death.

Phosphates are slowly and incompletely absorbed when ingested. If ingested symptoms may include vomiting, lethargy, diarrhea, blood chemistry effects, heart disturbances, and central nervous system effects (seriously and you’re adding this to our water?) The toxicity of phosphates is because of their ability to sequester calcium.

Phosphate and Orthophosphate products are expected to be toxic to aquatic life when present in high concentrations, mainly due to their acidic nature. When released into the soil, this material may leach into groundwater. When released to water, natural water hardness minerals may readily reduce acidity. The phosphate, however, may persist indefinitely. During transport through the soil, phosphoric acid will dissolve some of the soil material carbonate-based materials. The acid will be neutralized to some degree. However, significant amounts of acid will remain for transport down toward the groundwater table. Since it is an inorganic compound and contains no degradable functional groups, it exerts no biological oxygen demand.

There are options other than chemicals to treat water systems for scale and corrosion. There is no excuse to allow this old way of thinking to be the main tool for water treatment. Chemicals are bad for us and the environment. We all know this, but municipalities and corporations are either too lazy or too scared to change how this is done. Our health depends on them getting with the times and stop thinking that old solutions are the best and only solution. Innovate your mind and understanding with what we now know as facts.

Distribution Systems can be the Source of Chemicals in your Water.

Basically, this means the pipes that bring the water to your home are contaminating your water. The most widely used metal for pipes and fittings in distribution systems is iron, which may give rise to corrosion products. These products can cause discoloration at the tap if the distribution system is not managed correctly. Monitoring for corrosion products is not appropriate; instead, it is necessary to manage the problem of corrosion and the accumulation of corrosion products in distribution. In some circumstances, iron hand pumps can give rise to discolored water if they are corroded by water that is too acidic. In such cases, it may be appropriate to screen the raw water for low pH and, where a low pH is detected, consider using alternative materials for the pumps. The corrosivity of water is a function of many factors, including pH, low alkalinity, chloride, and sulfate ions, sediment, and microbial activity.

Lead, copper, and sometimes zinc may be present in drinking water, because of the use of these metals in pipework in public, commercial and domestic buildings. Monitoring is complicated by the fact that both occurrence and concentration will vary from building to building and at different times of the day. Concentrations will usually be greater the longer the water is standing in the pipe, so first-draw water will usually have higher levels than water from a fully flushed system. Copper and zinc are less likely than lead to occur at levels of concern, except in very new buildings or where highly corrosive water is supplied; however, concentrations may be increased in some circumstances when copper piping is used as a means of earthing the electrical system in a building. Lead frequently occurs at concentrations greater than the guideline value in situations where lead pipes and solders are present. Lead is also a component of brass, bronze, and gun-metal, which are used in fittings in plumbing systems. In some circumstances, fittings made of these metals can be a significant contributor to the concentrations of lead at the tap. Monitoring of metals from plumbing is difficult because of variations in concentration with time and the fact that the levels are frequently property-specific.

Where lead pipes are present in many buildings, the most important requirements are public health surveillance (to ensure that there is no significant public health problem) and identification of the buildings that have lead piping. Consideration of lead in drinking water should be part of an overall lead-reduction strategy because lead exposure from other sources may be more significant. There are several possible approaches to reducing lead levels in drinking water, ranging from targeted replacement of lead pipes to central control of corrosion to reduce the possibility that lead will dissolve in water. Lead can also arise if lead solder is used in the installation of copper piping. A control measure, in this case, would normally be to avoid the use of lead solders for applications involving drinking water.

Polyvinyl chloride (PVC) plastic pipe is also widely used in distribution systems. Lead has been used as a stabilizer in unplasticized PVC pipe and may give rise to elevated lead levels in drinking water for a time after a new installation. Such pipe is normally of large diameter; thus, the dilution effect of the water flowing through the pipe will reduce the concentration of lead and may result in lead concentrations below the guideline value. There have been cases where the levels of vinyl chloride monomer remaining in the plastic have been higher than desirable.

We know there are safe, more effective, less costly alternatives to dealing with the issues that chemicals address. If you want to learn more, please follow the link. Want an alternative to water treatment that doesn’t use Chemicals?