DEAR JOAN: I want to wade in on the discussion about cigarette filters. Besides the fact that they are ugly and pollute, they are also full of toxins.

There was a nest in my front entrance and I saw a cigarette butt among the nesting materials. Cigarette butts also get into the waterways and harm the fish.

If you do smoke, please don’t throw the finished cigarette on the ground. Please be aware of how your actions affect the animals we share this fragile planet with.

Eva Lowe, Hayward

DEAR EVA: Cigarette butts do create an environmental hazard, and the filters might be the biggest offenders. Because they contain mostly plastic, they do not biodegrade and can lie around for decades, filled with nasty chemicals.

Of the 6 trillion cigarettes smoked worldwide each year, about 4 trillion end up tossed into the environment, researchers say.

When those cigarettes get into waterways, the concentrates of nicotine and chemicals create a powerful and deadly solution, killing fish and other water creatures. Studies have shown that just one cigarette butt soaked in a liter of water for 96 hours leaches out enough toxins to kill half the fresh or salt-water fish exposed to it.

Cigarettes aren’t just dangerous to marine life. Animals, as well as small children, can be tempted to eat or chew them, which releases their deadly concoction.

The ironic thing is that those filters don’t even protect smokers. They originally were designed to keep tobacco from getting into the smoker’s mouth. Later, they were marketed as a device to reduce the amount of harmful chemicals being inhaled — but they don’t. The U.S. National Cancer Institute reported that filters do not provide any health benefits for smokers.

They aren’t good for plants, either. Tobacco from discarded cigarettes, or on the hands of smokers, can spread tobacco mosaic virus, which pretty much means you’ve got serious problems with your tomatoes and other plants.

Sounds like giving up smoking would be a good thing for the smoker, the environment and for animals.

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DEAR JOAN: We adopted two beautiful Maine coon cats from ARF several years ago. They were indoor cats at first, but after his brother died from a heart attack, we didn’t have the heart to keep (the remaining cat) in the house alone. He loves being outdoors and is far happier now.

Early the other night, just after dark, I was on the computer, heard a noise and went to the door. He was standing there, wanting in with a tail three-times as fat as it normally is. I’ve seen this on other cats we have had over the years, but this is the first time I have seen him with it.

Are they trying to look larger and fiercer than normal to fend off a threatening animal?

Mike Johnson, Lafayette

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Concerned Saratoga residents putting water out for wildlife but it’s not a good idea DEAR MIKE: Cats puff up their tails and their entire bodies when they are frightened or angry. As you suggest, they do it in an attempt to make themselves look larger.

Considering your cat was wanting in, I’m guessing he was frightened.

I know you think your cat is happier outdoors, but obviously something upset him. If it was a coyote or a large dog, you’re lucky that you got him back at all.

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