EPA Offers Exposure Guidance on PCBs in Caulk of Older Buildings
October 12, 2009 // Published as a news service by IHS
The U.S. Environmental Protection Agency (EPA) will offer guidance to building owners and school administrators on how to reduce exposure to polychlorinated biphenyls (PCBs) that may be found in caulk in buildings constructed or renovated between 1950 and 1978.
The EPA is also conducting new research to better understand the risks posed by caulk containing PCBs.
Although Congress banned the manufacture and most uses of PCBs in 1976 and they were phased out in 1978, there is evidence that many buildings across the country constructed or renovated from 1950 to 1978 may have PCBs at high levels.
These PCBs are found in the caulk around windows and door frames, between masonry columns and in other masonry building materials, according to the EPA.
Exposure to these potentially cancer-causing PCBs may occur as a result of their release from the caulk into the air, dust, surrounding surfaces and soil and through direct contact, EPA experts said.
EPA calculated public health levels that maintain PCB exposures below the "reference dose" - the amount of PCB exposure the EPA does not believe will cause harm. Those levels vary depending on the age group and use assumptions about potential PCB exposures from other sources, such as diet.
If buildings were erected or renovated between 1950 and 1978, the EPA recommends that owners implement steps to minimize exposure to potentially contaminated caulk including cleaning air ducts and improving ventilation.
The EPA also recommends that owners test peeling, brittle, cracking or deteriorating caulk directly for the presence of PCBs and remove the caulk if PCBs are present at significant levels. The building owner can also assume the PCBs are present and proceed directly to remove deteriorating caulk.
Building owners and facility managers should also consider testing to determine if PCB levels in the air exceed the EPA's suggested public health levels, experts said. If testing reveals PCBs in the air above these levels, building owners should implement and monitor ventilation and hygienic practices to minimize exposures.
Owners and managers are encouraged to retest PCB levels in air to determine whether these practices are reducing the potential for PCB exposures. If these practices do not reduce exposure, EPA experts said caulk and other known sources of PCBs should be removed.
The EPA is doing research to determine the sources and levels of PCBs in buildings in the U.S. and to evaluate different strategies to reduce exposures. The results of this research will be used to provide further guidance to building owners as they develop and implement long-term solutions.
More information including test methods for evaluating PCBs can be found at http://www.epa.gov/pcbsincaulk.
Source: U.S. Environmental Protection Agency (EPA).