What are Polychlorinated biphenyls (PCBs)?

Caulk containing high levels of PCBs (polychlorinated biphenyls) has been found in many schools and other buildings built or remodeled before 1978. Because PCBs can migrate from the caulk into air, dust, surrounding building materials, and soil, EPA is concerned about potential PCB exposure to building occupants.

Health impacts of PCB exposure

PCBs are man-made toxic chemicals that persist in the environment and bioaccumulate in animals and humans. PCBs were manufactured in the United States between 1950 and 1978, before their manufacture was banned by Congress due to concerns about their potential for adverse effects on human health and the environment. Exposure to PCBs can affect the immune system, reproductive system, nervous system, and endocrine system. In humans, PCBs are potentially cancer-causing.

Protect children and other building occupants

The preventive steps described below can help reduce exposure to PCBs in caulk until it can be removed.

  • Improve ventilation and add exhaust fans.
  • Clean frequently to reduce dust and residue inside buildings.
  • Use a wet or damp cloth or mop to clean surfaces.
  • Use vacuums with high-efficiency particulate air (HEPA) filters.
  • Do not sweep with dry brooms and minimize the use of dusters.
  • Wash hands with soap and water after cleaning and before eating or drinking.

Test for PCBs in buildings built between 1950 and 1978

If school administrators and building owners are concerned about exposure to PCBs and wish to supplement these steps, EPA recommends testing to determine if PCB levels in the air exceed EPA’s suggested public health levels. If testing reveals PCB levels above these levels, schools should attempt to identify any potential sources of PCBs that may be present in the building, including testing samples of caulk and looking for other potential PCB sources (e.g., old transformers, capacitors, or fluorescent light ballasts that might still be present at the school).

If elevated air levels of PCBs are found, schools should also have the ventilation system evaluated to determine if it is contaminated with PCBs. Although the ventilation system is unlikely to be an original source of PCB contamination, it may have been contaminated before other sources of PCB’s were removed from the school and may be contributing to elevated air levels. Contaminated ventilation systems should be carefully cleaned. Ideally, such cleaning should be planned in concert with removal of any sources of PCBs that are found to avoid re-contamination of the system.

During the search for potential sources, schools should be especially vigilant in implementing practices to minimize exposures and should retest to determine whether those practices are reducing PCB air levels. EPA will assist in developing a plan to reduce exposure and manage the caulk. Your EPA regional PCB coordinator can direct you to a PCB testing lab; see the back cover for more information.PCBs were not added to caulk after 1978. Therefore, in general, schools built after 1978 do not contain PCBs in caulk.

Avoid exposure to PCBs in building caulk

Caulk that is peeling, brittle, cracking, or deteriorating visibly in some way may have the highest potential for release of PCBs creating dust. In addition to inhalation from PCBs in the air or dust, exposure may occur when a person comes in contact with the caulk and any surrounding porous materials into which the PCBs may have been released (e.g., brick, concrete, wood). Exposure may also occur through contact with PCB-contaminated soil adjacent to buildings. Soil may become contaminated with PCBs when caulk weathers.

Protections during removals, renovations

Schools, building owners, and daycare providers in public and commercial buildings need to follow PCB-safe renovation practices to minimize potential exposures resulting from renovations to workers, teachers, and children.

It is important to manage the removal in a way that minimizes workers’ exposure to the PCBs (e.g., use protective clothing such as facemasks, gloves, etc.) and prevents the release of PCBs into the environment. The work practices described below can help reduce exposure to PCBs in caulk until it can be removed.

In addition to the safeguards mentioned above:

  • Wear appropriate protective clothing when conducting cleanup activities.
  • Dispose of all cleanup materials (mops, rags, filters, water, etc.) in accordance with all federal, state, and county regulations.
  • For caulk used on windows, walls, columns, and other vertical structures that people may come into contact with, use heavy-duty plastic and tape to contain the area so that caulk or dust and debris from the surrounding masonry do not escape. The plastic should cover the caulk and surrounding areas of masonry.

Source: USEPA Website