Dear Umbra,

I have been cutting out old cushions, filling them with dirt, and planting them for some years now. I found the first two floating in the river (while canoeing). Since then, I’ve gotten them from the trash; I don’t pay anything for them. I use them to grow everything from herbs to prairie plants to succulents to water plants. I have even used cut-up, leftover cushions in bog gardens (in the bottom part along with newspaper and cat litter). Most cushions contain mold- and fire retardants, and I understand there was a problem with one fire retardant showing up in breast milk. How bad or good are my cushions from an environmental point of view?

Columbus, Ohio

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Dearest Cindy,

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I just have to ask: Do you ever lounge around on your planters? Are they aesthetically pleasing?

As for your question — well, there seems to be a shortage of research on the environmental effects of gardening with cushions. Go figure. But you’re certainly winning on several counts: removing waste from the waste stream; reducing your consumption of new planter pots (with their associated manufacturing and shipping impacts); cleaning up unsightly detritus; and nurturing air-filtering plants. So far, so good.

But now for the bad news: Polybromo diphenyl ethers, a class of fire retardants, persist in the environment and have recently been found almost everywhere — not only in human breast milk, but also in fish, other aquatic life, and fatty tissues of all sorts. Little is known about them, but they are suspected of causing cancer and reproductive-system damage. The European Union instituted a precautionary ban on PBDEs in 2001, and some scientists are calling them the new PCBs. Sounds bad, but to date, there’s been very little definitive research on the possible dangers.

Like PCBs and DDT before them, PBDEs accumulate in the food chain. They are almost certainly present in your cushions; if so, by using the cushions as planters, you are coming closer to ingesting them than was intended (or imagined) by the manufacturer. Presumably you aren’t munching on your cushions while you weed, but it is possible that fire retardants or other chemicals from the cushion are leaching into the soil, and from there into the plants’ roots. Growing edibles in these novel receptacles is probably hazardous. Even if you stick to ornamentals, you’re not entirely in the clear: As the cushions degrade, the PBDEs are likely released into the soil and taken up by local insects, and from there it’s just a matter of time until they make their way up the food chain (and throughout your garden). To be on the safe side, keep away from the cushions — but by all means carry on with your imaginative scavenging.

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