Our friends at Earth911 have recently alerted me anew to the hazards of mercury in products we might need to discard or recycle. I recall, as a child, having a small, but very heavy jar of liquid mercury that we thought was neat stuff and played with on occasion. It puddled in fun ways or could turn a copper penny silver by rubbing it on the surface, for example.

The EPA has a good website that describes in detail the kinds of neurological problems this sort of mishandling of mercury can cause, and the conditions under which a person is most vulnerable. I will leave it to others to decide how much I was personally affected.

In any case, the stuff can be absorbed through the skin, or inhaled as an invisible, odorless, and very toxic vapor (it will evidently evaporate in room conditions, but, of course, heating it for any reason, accelerates that process). Combined with inorganic chemicals, it can form salts that are used in photography and wood preservation.

When it combines with organic compounds, it forms methylmercury, which is a highly toxic environmental pollutant sometimes released by coal-burning power plants and is also the form found in seafood, about which we are regularly warned.

In the home, mercury has most often been found in mercury thermometers, where it is not a problem until the thermometer breaks. Cleanup is then very difficult, so the best route is to deliver any such device you still have to Household Hazardous Waste Day before it breaks. Note that, if the liquid in your thermometer is any color other than silver, it is not mercury, so is safe to use. Most thermometers today are actually digital and contain no liquid at all, but a few of the older ones still exist.

Room thermostats were the other big source of mercury in the home. Those are not programmable, and should probably be replaced for fuel savings, but if there is a small glass bulb inside, with silver liquid in it, that is likely mercury, and the device should be handled as Hazardous Waste.

A few years ago, we were all encouraged to switch to Compact Fluorescent Lightbulbs to save energy. These all contain mercury, as well as some other hazardous chemicals, so they need to be handled carefully, especially if they break.

The EPA has some detailed procedures for handling broken bulbs, but it’s better to take them back to the store before they break. Places like Lowes and Home Depot have bins where you drop them off — each in a tightly sealed plastic bag, like the ones the newspapers come in on rainy days — and the stores dispose of them as the sort of hazardous waste they are.

You cannot put these devices in the trash. LED bulbs do not have these issues, and last longer as well.

Electronics can also contain mercury switches or displays that contain mercury, as well as a wide variety of recoverable, and sometimes highly valuable, other materials. None can be safely put into the trash, but all can be recycled by taking them to a staffed office of Goodwill or returning them to the store from which they were purchased.

Finally, Earth911 reminds us that mercury was much more widely used in the past, so even things as seemingly benign as old mirrors, vases, or pendulum clocks can contain significant amounts of mercury. All need to be discarded in a responsible manner that ensures they are disassembled and recycled, not dumped someplace where their toxins can spread.

The Recycle Bin is a weekly column on what to recycle, what not to recycle, and why, in Brunswick. The public is encouraged to submit questions by email to brunsrecycleinfo@gmail.com. Harry Hopcroft is a member of the Brunswick Recycling and Sustainability Committee. This column is a product of his own research.

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