Clean water is essential for drinking, as well as for use in food and beverage production. Only 3% of water in the world is fresh, but fresh water sources can contain chemical contaminants, like perfluorooctanoic acid (PFAS) and arsenic, as well as microbiological contaminants, and pathogens. Even after the treatment process, residual chemicals and contaminants in drinking water can exceed safe and legal levels. Municipalities, private water treatment stations, and food and beverage production facilities must regularly test their water supply to ensure chemical and microbiological contaminant levels are kept at or below compliance levels set by regulatory agencies. With a growing global population, the demand for fresh water is predicted to increase by 40% by 20301, With increased demand, maintaining efficiency and accuracy in water testing will provide a constant challenge.
Any industry that produces, uses, or processes drinking water must comply with national regulations and perform regular tests to ensure that drinking water is free of chemical and microbiological contaminations. Common chemical contaminants include aluminum, ammonium, bromate, iron, manganese, chloride, nitrate, nitrite, sulfate, chromium, and other metals.
Additional testing is performed when certain industrial environmental pollutants may be present. Volatile organic compounds (VOCs) are often used during manufacturing, including the production of petroleum products, adhesives, pharmaceuticals, paints, or refrigerants. VOCs are also used as gasoline additives, solvents, hydraulic fluids, and dry cleaning agents. VOC contamination is a human-health concern because many are toxic and are known or suspected human carcinogens.
Fresh water supplies can also be a source of pathogens, leading to the spread and transmission of diseases without microbiological control. Testing the water supply for every pathogens is expensive and time consuming, so indicator organisms are used as assays to detect fecal and other contaminations. Coliforms, Escherichia coli, and Klebsiella pneumoniae are typically used for testing for fecal contamination.
Microbiological testing of commercial beverages and water products is essential to ensure that they are safe to drink, but also to prevent spoilage. Bacteria, yeasts, molds, and pathogens that occur in raw materials or during the production process can decrease the quality and safety of finished products. Both municipal and commercial water supplies are frequently tested to meet regulatory requirements.
Disinfection of drinking water reduces the risk of pathogenic infections, but the process can leave behind residues and disinfection byproducts (DBPs) that can pose risk to human health. Additionally, organic and inorganic pollutants may be naturally present in our water supply at its source. The identification of pollutants and DBPs is essential to ensure safe consumption.
Since contaminated water is harmful to humans and the environment, regulatory agencies, like the U.S. Environmental Protection Agency (USEPA), require the use of official standardized methods (e.g., ISO, EPA, AOAC) for testing drinking water and wastewater. These techniques include quantitative testing, chromatography, spectrophotometry, reflectometry, physical parameter measurements (e.g., cloud point, color, hardness, pH, odor), and pathogen testing (molecular or cell culture-based). These quality control tests are done both at the input source, after in-process filtration steps like flocculation and clarification, and also at post-filtration outputs, including tap sampling.