I was recently made aware of an issue regarding the oil used in the construction of certain high voltage capacitors made prior to the 1980's. These capacitors were filled with oil containing PCBs (Polychlorinated Biphenyls) - a known carcinogen and substance that is on the watch-list of several regulatory agencies including Environment Canada. It should be noted that it is unlawful to sell or import components containing this substance and - depending where you live - it may be unlawful to be in possession of components that contain PCBs.
What are PCBs? Polychlorinated Biphenyls were widely used in cooling and dielectric materials in the production of transformers and capacitors. They were also used in the production of cutting fluids for machining, lubricating oil, hydraulic fluid, paint and plastic additives and in carbon-less copy paper (NCR paper).
When were they banned? In the United States, PCB production was banned in 1979 and most other jurisdictions followed within a few years.
How can I identify components that may contain PCBs?
Most transformers, oil-filled capacitors, and fluorescent lamp ballasts manufactured before 1979 contain PCBs. Components manufactured without PCBs will actually be marked "NO PCB"
Common trade names for PCB Capacitors (not extensive):
Please see the side-bar for some links to identification resources.
What can I do if I have some PCB containing components?
If you suspect that you have any components that contain PCBs, you should place them in a sealed plastic bag. It's important to use latex or nitrile gloves when handling components that have (or are suspected of having) PCBs, especially if there is oil leaking out of the components. It goes without saying, that you should wash your hands thoroughly after handling any electronic components.
Next, contact your local environmental authorities. Here's where your good conscience will have to prevail over your desire to save money. Many jurisdictions do not offer a free pickup or disposal service and it is the responsibility of the owner to have the material safely transported and disposed of. Depending on how much material is involved, it can be costly.
Of course, the key to ensuring that you don't harm the environment, land in hot-water with the authorities, or spend hard-earned money on disposal of your capacitors is to not acquire them in the first place. Identifying them at the source of supply is important. This could be an auction, flea-market, estate sale, ham-fest, or even picking on trash-day. You should inform the sellers that they may be in violation of environmental law and in the process, putting themselves in danger. Encourage them to do the right thing.