The pH scale measures how acidic or basic a substance is, ranging from 0 to 14. A pH of 7 is neutral, while values below 7 indicate increasing acidity. Values above 7 denote increasing alkalinity. Low pH, meaning an acidic substance or environment, can have widespread negative consequences for living organisms, man-made structures, and natural ecosystems.
How Low pH Harms Human Health
Low pH directly impacts human health, primarily through drinking water and internal processes. Acidic drinking water can corrode pipes, especially older ones, leading to the leaching of heavy metals like lead and copper into the water supply. Ingesting these metals can cause various health issues, including nausea, vomiting, organ damage, and developmental delays in children.
Direct consumption of acidic substances can contribute to acid reflux, heartburn, and dental enamel erosion. The body maintains a tightly regulated blood pH, typically between 7.35 and 7.45. When blood pH drops too low, a condition known as acidemia or acidosis occurs, a severe medical concern. Acidosis can impair enzyme function, affect glucose utilization in brain cells, and, if left untreated, may lead to symptoms like nausea, vomiting, fatigue, confusion, shock, coma, or death.
The skin is also susceptible to low pH. Healthy skin maintains a slightly acidic pH, typically between 4.7 and 5.75, which helps protect its moisture barrier and fight off harmful bacteria. When the skin’s pH shifts too far into the acidic range, it can disrupt this protective acid mantle, leading to increased dryness, irritation, redness, and sensitivity.
Environmental Harm from Low pH
Low pH levels damage natural environments and ecosystems. Aquatic life is particularly vulnerable, as acidic water bodies harm fish, especially during critical life stages like egg and fry development. Fish and macroinvertebrates can experience decreased reproduction, stunted growth, increased susceptibility to disease, and mortality in acidic conditions. Low pH also mobilizes and leaches toxic metals, such as aluminum, from soil and sediment into water, increasing toxicity to aquatic organisms.
Extreme pH levels can impede biological enzyme functions essential for ecosystem functions. Photosynthesis in plants and decomposition by microorganisms can be disrupted, disturbing natural nutrient cycles. Acidic soil, often a result of acid rain, can leach essential minerals and nutrients, making them unavailable for plant uptake, mobilizing toxic elements like aluminum that damage root systems.
Environmental acidity also affects various materials in the natural world and human constructions. Acid rain can corrode natural stone monuments, statues, and historical buildings made of limestone and marble. It can also damage paint on outdoor structures and corrode metals such as bronze, nickel, zinc, copper, and carbon-steel.
Low pH’s Impact on Homes and Structures
Low pH water poses significant threats to household plumbing and structures, leading to costly damage and maintenance issues. Acidic water corrodes metal pipes and plumbing fixtures, often resulting in leaks and a reduced lifespan. This corrosion manifests as blue-green stains on sinks, tubs, and fixtures, particularly with copper piping. If iron pipes are present, rust stains may appear.
Beyond visible staining, the corrosive action of low pH water can impart a metallic or sour taste to tap water. It also reduces the efficiency and shortens the lifespan of water-using appliances, including water heaters, dishwashers, and washing machines, by corroding their internal components and seals. This accelerated wear can lead to frequent repairs or premature replacement.
Why pH Drops and What Can Be Done
Low pH in water sources can arise from both natural occurrences and human activities. Naturally, decomposition of organic matter, volcanic activity, and certain rock formations like granite can contribute to water acidity. Rainwater is naturally slightly acidic due to dissolved carbon dioxide, around pH 5.6.
Human-made causes are substantial contributors to low pH issues. Industrial emissions, particularly sulfur dioxide and nitrogen oxides from the burning of fossil fuels in power plants and vehicles, are primary culprits in the formation of acid rain. Agricultural runoff, chemical waste discharge, and mining activities also release acidic substances into water systems.
To mitigate low pH, solutions are employed. Water treatment facilities adjust pH by adding alkaline substances to neutralize acidity. For individual homes, neutralizer tanks containing crushed limestone (calcite) can be installed to raise the water’s pH as it flows through. Chemical feed pumps that inject soda ash are another method for treating acidic water. These measures help protect plumbing, appliances, and overall water quality.