Testing Needed for PCBs in Indoor Air
Posted by Rebecca McDaniel on Mon, Dec 14, 2009 @ 06:31 AM
By Jason Atwood, Field Service Manager
In recent months, public scrutiny surrounding the presence of PCB's in materials commonly used in public school building construction prior to 1978 has been mounting. Media coverage and an onslaught of resulting attention have forced this issue to the forefront of public health and safety concerns pertaining to our environment. Typically - this focus has been aimed at the presence of the contaminated caulking itself: in window glazing/caulking, interior and exterior joint compounds, in Univent construction, paints, etc.
While building inspections and intensive sampling plans will certainly illustrate the cause of concern (I.E. The presence of PCB contaminated material is the crux of the issue), the true effect may not become evident without a stringent air monitoring / sampling plan. PCBs do not become an immediate hazard until they are ingested into the human body, be it through consumption, absorption or inhalation.
The latter may be the issue of greatest concern in the context of classroom hazards. PCBs have the ability to volatilize - that is tiny particles of the material can vaporize from the solid state and become airborne, a process that is expedited with the presence of heat. Window caulking and glazing subject to extended exposure to the sun, PCB ballast material that may leak inside of fluorescent lighting and PCB containing material within or immediately around HVAC systems all pose a significant risk for volatilization. Once airborne, PCB particles mix with other sources of airborne dust and can be directly inhaled, or can deposit on horizontal surfaces and then be ingested or absorbed.
To ensure your school department engages in a robust and encompassing risk assessment plan, it is imperative that they focus not only on potentially impacted materials, but also on the byproducts of those materials in the form of airborne PCB concentrations and associated surface dusts. The EPA has established guidelines for acceptable PCB concentrations for both of these medias, taking into account all potential sources of human ingestions of PCBs and how those risks align with the risks outlined herein. These guidelines can be found here.
As with all environmental concerns, effective assessment is essential in the development of a risk management plan. PCBs in building materials, air, dusts, and soil are all manageable risks that can mitigated through effective remediation efforts. As public scrutiny surrounding this issue has intensified, so also has our ability in the environmental services industry to protect families from future exposure and the resulting detrimental health effects.