Water quality directly impacts human health. Even in regulated supplies, contaminants can enter the system, meaning waterborne illness should never be overlooked. Recognizing a problem requires paying attention to both the body’s physical reactions and changes in the water itself. Identifying these signs is the first step in determining if your drinking water is the source of unexplained sickness.
Health Symptoms Indicating Illness
Gastrointestinal symptoms frequently serve as the primary warning signal against contaminated drinking water. Exposure to pathogenic microorganisms often results in acute gastroenteritis, presenting as watery diarrhea, abdominal cramping, and persistent nausea. Vomiting may also occur, which can rapidly lead to dehydration, especially in young children or the elderly.
Water contaminants can also trigger dermatological issues. Skin irritation, dryness, and unexplained rashes may arise from bathing or washing with water containing high levels of certain chemicals or minerals. Heavy metals or excessive chlorine can compromise the skin’s natural barrier, leading to chronic discomfort or allergic reactions.
For some contaminants, the effects are systemic, developing over prolonged exposure. High levels of nitrates pose a serious risk to infants, causing methemoglobinemia, known as “blue baby syndrome,” which reduces the blood’s capacity to carry oxygen. Long-term exposure to heavy metals, such as lead or arsenic, can contribute to chronic fatigue, cognitive impairment, or neurological issues, which can be particularly damaging to vulnerable populations.
Visual and Sensory Indicators of Contamination
The water’s appearance provides immediate clues about potential contamination. Cloudy or turbid water often contains suspended solids like silt, clay, or organic matter, which can harbor harmful microorganisms. Discoloration, such as a brown or orange tint, suggests high levels of iron or rust from aging pipes.
Sensory changes involving taste and smell can point toward specific issues in the water supply. A distinct metallic taste is linked to elevated concentrations of heavy metals like copper or lead, which may have leached from plumbing materials. A soapy or chemical taste suggests the presence of industrial runoff or excessive treatment chemicals.
An unusual smell should prompt immediate concern. A scent similar to rotten eggs is a telltale sign of hydrogen sulfide gas, often produced by sulfur bacteria in the water source or well system. While clear water is expected, many serious contaminants, including bacteria and most dissolved chemicals, are entirely odorless, colorless, and tasteless.
Common Contaminants Causing Sickness
Waterborne sickness is often caused by biological pathogens, which are living organisms that cause acute illness upon ingestion. These include bacteria (E. coli, Salmonella), viruses (Norovirus), and protozoa (Giardia, Cryptosporidium). These microorganisms typically enter the water supply through system breaches or from agricultural and septic runoff mixing with groundwater or surface water.
Chemical contaminants represent a different threat, often leading to chronic health effects from long-term exposure. These substances include pesticides and herbicides that can leach into groundwater from agricultural fields. Industrial solvents, such as volatile organic compounds, can infiltrate the water supply through improper waste disposal.
Heavy metals are a major category of concern, originating from both natural deposits and aging infrastructure. Arsenic can occur naturally and dissolve into groundwater, while lead and copper enter drinking water through the corrosion of older household plumbing and service lines. Nitrates, which derive from fertilizer use and septic systems, are converted to harmful nitrites in the body, directly impacting oxygen transport.
Next Steps: When and How to Test Your Water
If you experience unexplained illness or notice a sudden change in your water’s appearance, taste, or smell, stop using it for drinking or cooking immediately. Switching to an alternative safe source, such as bottled water, minimizes further exposure. If you are supplied by a public water system, promptly notify the local health department or water utility to report the issue.
For individuals who rely on private wells, the responsibility for testing falls entirely on the homeowner. Private wells should be tested at least annually for total coliform bacteria and nitrates, and more frequently if there are nearby changes in land use or unexplained sickness. After an event like a flood, which increases the risk of microbial contamination, testing for bacteria is important.
Water testing should be conducted by a state-certified laboratory rather than relying on less comprehensive at-home kits. Professional laboratories can perform detailed analyses for a wide range of contaminants, including heavy metals and specific organic chemicals. Contacting the local health department can help identify which contaminants are most common in your area, ensuring the laboratory runs the most relevant tests.