Last weekend, I spent a great couple days hiking through the lush and scenic Columbia River Gorge area that straddles Oregon and Washington.

Our trek led some friends and I through dense forests and past several amazing waterfalls that seem to spill out of every nook and cranny throughout this stretch of the Cascades.

The path up to one popular waterfall featured lots of interpretative Park Service signs about the local wildlife, plants, ecosystems, and environment. I always stop and read those signs and learn stuff I never knew. (For instance, the Cascades are home to fat, squeaky, rabbit-like rodents called pikas.)

It was from one of these park service signs that I learned just how destructive cigarette butts are to the environment. Many people wrongly think that these butts biodegrade quickly, which may be why they're the most littered item in the world. But the sad fact is that cigarette filters are made primarily of plastic, which takes decades to degrade.

Meanwhile, irresponsible smokers constantly toss out their butts, treating the planet as if it were their own personal ashtray.

The problem is that littered cigarette butts ultimately become toxic to the environment. In other words, second-hand smoke isn't just dangerous to co-workers and babies.

According to CigaretteLitter.org, a not-for-profit group that runs educational campaigns on the issue, billions of butts are flicked out each day on to beaches, nature trails, gardens, and public parks. Yes, they're ugly. Even worse is that they harm or kill fish, birds, and little pikas out there in the wild.

Experts at Healthy Waterways say that threat is especially high for aquatic animals, such as fish, birds, and whales, who mistake the floating butts in the water for food. They ingest the butts, and become poisoned by the chemicals. The plastic fragments from those butts regularly turn up in the stomachs all kinds of marine creatures. Seems that fish and mammals don't react terribly well to stuff like benzene, formaldehyde, ammonia, acetone, and tar.

The other problem is that the same chemicals leach into the environment, and contaminate the water or soil. Thanks to wind and weather, the butts often end up in waterways, causing all those toxins to jeapordize water supplies.

Meanwhile, if you know a cigarette litterer, introduce them to a issue by sending an anonymous e-mail. It's designed to alert them to the impact that their careless flick of the wrist might have on the planet. And on all those hapless little pikas.