“The most important step parents, doctors, and others can take is to prevent lead exposure before it occurs.”
- HealthChildren.Org, from the American Academy of Pediatrics
What is lead and where does it come from?
Lead is a naturally occurring toxic metal.
Lead in the environment mostly results from human activity including mining, smelting, manufacturing, and recycling. Lead’s also been used in paint and fuel, among many other products such as in lead-based solder, paint, glass, toys, jewellery.
From the extensive use of lead, it can be found in the water, air, soil, and inside buildings like our homes and schools.
How does lead get into our drinking water?
The most common sources of lead in drinking water are lead pipes, faucets, and fixtures. In homes with lead pipes that connect the home to the water main, also known as lead services lines, these pipes are typically the most significant source of lead in the water. Lead pipes are more likely to be found in older cities and homes built before 1986. Among homes without lead service lines, the most common problem is with brass or chrome-plated brass faucets and plumbing with lead solder.
Lead can enter your drinking water when plumbing materials that contain lead corrode. Corrosion is a dissolving or wearing away of metal caused by a chemical reaction between water and your plumbing.
Is there a safe level of lead in drinking water?
Both the US EPA and World Health Organization has stated that there is NO safe level of lead in water because lead can be harmful to human health even at low exposure levels.
The Safe Drinking Water Act (SDWA), the federal law that protects public drinking water supplies, states that the maximum allowable lead content is a weighted average of 0.25 percent calculated across the wetted surfaces of pipes, pipe fittings, plumbing fittings, and fixtures and 0.2 percent for solder and flux.
How can lead exposure hurt human health?
Pregnant women
Lead can accumulate in our bodies over time, where it is stored in bones along with calcium. During pregnancy, lead is released from bones as maternal calcium and is used to help form the bones of the fetus. This is particularly true if a woman does not have enough dietary calcium.
Lead can also cross the placental barrier exposing the fetus to lead. This can result in serious effects to the mother and her developing fetus, including:
Gestational hypertension
Spontaneous abortion
Low birth weight
Impaired neurodevelopment
Infants and new moms
Lead levels in breast milk tend to be low; breast milk is highly nutritious and the best choice for most babies.
Formula-fed infants who are exposed to lead through contaminated tap water are at higher risk for lead exposure because of the large volume of formula they drink compared to their body size.
Children
Behavior and learning problems
Lower IQ and hyperactivity
Slowed growth
Hearing problems
Anemia
In rare cases, ingestion of lead can cause seizures, coma and even death
Adults
Cardiovascular effects, increased blood pressure and incidence of hypertension
Decreased kidney function
Reproductive problems (in both men and women)
Further reading for physicians
Effects of Workplace Hazards on Female Reproductive Health (National Institute for Occupational Safety and Health)
Lead Screening during Pregnancy and Lactation (American College of Obstetricians and Gynecologists)
Guidelines for the Identification and Management of Lead Exposure in Pregnant and Lactating Women (Centers for Disease Control and Prevention)
Lead Exposure and Lead Poisoning (American Academy of Pediatrics)
Lead Poisoning in Children (American Family Physician of the American Academy of Family Physicians)
