In the past month I have spoken to no fewer than four parents of children who were likely poisoned by lead dust from their duct work.
Ducts (along with bathtubs, and gutters/ downspouts) are among the most overlooked sources of early childhood lead exposure, from what I can tell. Paint is tested, soil is tested, house-dust is tested – but it seems to be a rare hazard assessor that gets down there, takes off the vent grill (or the air return grill) and tests the metal for lead (with an XRF or taking a dust-wipe sample.) Over the past month I have seen duct work come in with ranges from 5,000 to 44,000 parts per million lead – and children in these homes testing positive with blood lead levels ranging from 4 micrograms per deciliter to 72 micrograms per deciliter.
In two of these cases the child was “fascinated with the ducts” and “liked to watch the air movement and play right next to the heating vents”!
We’re talking about a central heating system here – and microfine dust – so wherever those contaminated ducts are blowing heat, they are also likely spreading this lead-contaminated dust which is potentially poisoning young children.
- If you are having work done on your house, make sure the ducts and air-returns are sealed so no dust or debris can enter your HVAC system.
- Change your filters at least as frequently as recommended by the manufacturer – especially if you live in an older home.
- Whenever you have your ducts cleaned look for a duct cleaning firm that is EPA RRP Certified. They should be aware of the proper precautions to take in the presence of lead dust (if not done properly, when the ducts are “cleaned”, the cleaning process can potentially result in microfine lead-containing dust being spewed all over your home.)
- Consider having your ducts “sealed“ after they are cleaned. My understanding of what this is: a sealant is blown through the entire duct work system (not just the parts near the floor that you can peer into.) The sealant is in the urethane family of products and fills in the tiny pits in the metal that most ducts are made of – pits which can catch and retain lead dust.
- After ducts are sealed – “cook” your heating system (turn it on high heat for a day or two) – and stay away from the house during that time. This way the VOCs from the sealant off-gas more rapidly and dissipate and you and your children are not inhaling those.