How Water Affects Children
Children interact with household water differently than adults. Understanding these differences helps inform thoughtful household decisions.
Kids & Household Water Guide
A parent-friendly guide to understanding how household water affects children and what you can be aware of.
Why Children Are Different
Children are not simply smaller adults. Their developing bodies absorb and process substances differently, they consume more water per pound of body weight, and their skin is thinner and more permeable. These biological differences mean children and adults experience the same household water in fundamentally different ways.
Exposure Per Pound of Body Weight
An infant who drinks formula mixed with tap water may take in significantly more water per pound of body weight than an adult drinking from the same tap throughout the day. This proportional difference means that any substance present in water — whether naturally occurring minerals, disinfection byproducts, or trace contaminants — is encountered at a higher ratio relative to body mass in children.
Public health researchers refer to this as a higher "dose-to-weight" ratio. Being aware of this difference can help parents make more informed choices about the water used for drinking, cooking, and preparing infant formula — particularly in households where water quality has not been recently tested.
Developing Biological Systems
Children's bodies are actively growing and developing. The kidneys, liver, digestive tract, and neurological pathways all undergo significant development during infancy and early childhood. Because these systems are still forming, children may process substances differently than adults.
This is a well-understood principle in pediatric science and is one reason why recommended guidelines for children often differ from those established for adults. Municipal water systems meet safety standards under the Safe Drinking Water Act, but understanding that developing bodies interact with their environment differently can help families approach household water with appropriate awareness.
Bath Frequency & Skin Sensitivity
Young children are typically bathed daily, involving extended full-body water contact. During bath time, children may swallow small amounts of water, and warm water can release volatile compounds like chlorine into enclosed bathroom air.
A child's skin is structurally different from adult skin — the stratum corneum is thinner and the skin barrier is still developing, making it more permeable. Combined with a higher surface-area-to-body-weight ratio, dermal contact is a more significant exposure pathway for children than adults.
Some families notice their children's skin appears drier or more irritated after bathing in water with higher mineral content or stronger disinfectant levels. This observation aligns with what we know about the developing skin barrier.
Plumbing-Related Lead Context
Lead in household water typically comes from plumbing, not the water source itself. Homes built before 1986 may have lead solder, lead pipes, or brass fixtures containing lead. When water sits in contact with these materials, small amounts can leach into the water — especially with hot water or overnight stagnation.
Young children are a population of particular interest because of their developmental factors. The EPA has set an action level of 15 parts per billion, while many public health organizations advocate for even lower thresholds when children are present. Knowing your home's plumbing age and materials is a practical first step.
Household Best Practices
Flush Cold Water Before Use
Let the cold tap run for 30 seconds to 2 minutes after periods of inactivity. This flushes water that has been in prolonged contact with plumbing materials. Always use cold water for cooking and formula — hot water leaches metals more readily.
Know Your Plumbing
Learn what materials are in your plumbing system, especially if your home was built before 1986. Your local water utility can tell you about lead service lines, and a plumber can identify materials within the home. Flush infrequently used taps periodically.
Stay Informed & Test
Review your utility's annual Consumer Confidence Report — it's free and details what's in your local supply. For a complete picture including what your home's plumbing contributes, consider professional water testing at the tap.
Request a Household Water Review
Knowing what's in your water is the first step to making informed decisions for your family.