Expert answers to eight varied concerns

Is the chlorine in my swimming pool safe? Are there non-chemical alternatives I can use to disinfect my pool?

Anyone who swims in a chlorinated pool knows that the chemical reddens the eyes, dries out the hair and skin, and smells bad. According to holistic doctor Andrew Weil, chlorine is also harmful to the respiratory passages and lungs. Studies have shown that children who frequently swim in chlorinated pools may be at increased risk of developing asthma. For example, a 2009 study from Belgium discovered that the more time teens spent swimming in chlorinated pools, the greater the incidence of asthma. The teens who swam the most were also more likely to suffer from hay fever and other allergies.

Only chlorine disinfects bacteria, kills algae, and oxidizes the pool (that is, gets rid of urine, sweat, and other body byproducts) and does so consistently throughout the area of the pool. However, there are alternatives that can reduce the amount of chlorine needed. All are more expensive than chlorine, and some require the water to be circulating, which means you have to run the pump continuously, upping your electrical use and bill.

Bromine, a chemical related to chlorine, doesn’t irritate the eyes and is a good sanitizer. But it doesn’t oxidize the pool as well as chlorine. Foamy water with a green tinge means bromine has been used in combination with chlorine. Bromine is roughly twice as expensive as chlorine.

Another option is an ionizer, which is a device that uses a low-voltage DC current to send either copper or silver into the water. This triggers a positive charge that attracts bacteria, germs and algae, which are then removed in the filtration system. However, with an ionizer the pump must be run continuously. An ionizer treating up to 40,000 gallons of water costs $300; the metals, which need to be replaced each season, run $129.

An ozonator, which inserts ozone gas into the pool through the filtration plumbing line, uses either UV light or a corona discharge generator to kill pathogens. It can reduce chlorine usage up to 90 percent and doesn’t require much power. However, the pump has to run continuously. An ozone generator is also expensive: a device treating 25,000 gallons costs $1200.

Only one alternative eliminates the use of chlorine entirely: PHMB (polyhexamethylene biguanide). The chemical punches through bacteria walls and wraps the dead pathogens in a gel, which sinks to the bottom and is sucked up by the vacuum. However, since PHMB only disinfects, it must be used in combination with hydrogen peroxide, which oxidizes the pool. Unfortunately, hydrogen peroxide has its own risks. PHMB chemicals cost about $725 a season for a 10,000-gallon pool.

In Europe, where people aren’t so finicky about germs, natural pools that don’t use chemicals have found a niche market. First introduced by Biotype, a company based in Austria in 1985, the chemical-free pools are designed with a section that’s filled with plants, which feed off of organic matter and hence filter the water. At least one company, Germany-based BioNova, is selling in the U.S., although the products are actually a kind of hybrid that combines the look of a natural pool with water that’s chlorinated or otherwise treated.

An eighteenth-century stone house I’ve fallen in love with and would like to purchase is located on a busy road. Is there any way I could mitigate the traffic noise?

Insulating the house will help. Replacing single-pane windows with double-paned glass and using sound-transmission-rated glass will help a lot. Installing window inserts on the inside of the windows will also help reduce noise penetration (as long as your windows aren’t open, of course).

If you have a huge yard, the most effective way to reduce noise levels is to create an earth berm. The berm would ideally be twelve feet high — above the level of the cars and trucks — which means the base would have to be 72 feet wide to meet state DOT regulations. That’s obviously way too big for most private spaces.

A solid, six-foot-high wall of stucco-covered concrete, brick, or stone is the most effective barrier to traffic noise, provided the house is within 300 feet of the road. (Generally, if you can see the source of the noise, you’ll hear it, so you’d probably have to build a higher wall to keep out the roar of trucks.)

A stockade or board fence is next best. The boards should reach all the way to the ground, since sound will travel through any gaps. Traffic typically measures 60 to 70 decibels, and the six-to-ten-decibel reduction caused by an eight-foot-high barrier is equivalent to replacing the screech of an old dishwasher with a refrigerator hum.

Planting vines along the wall or fence would serve to absorb noise that bounces off the stark surface or travels through the holes or slits in the barrier. However, a tall wall might suggest a prison yard. Putting in a low stone or brick wall will obviously not be as effective, though it can lessen the swoosh of tires.

Planting trees and shrubs also helps muffle sound, though a hedge would have to be 50 feet to absorb it completely. Plant tall, dense evergreens, such as spruce or fir, along the outer border of your property, then add shrubs of varying heights, such as juniper, holly, lilac and spirea. Obviously, the plants you choose must be adapted to the light, soil and drainage conditions of the site. Attractively planted vegetation will not keep out much of the noise, but it may seem like it, thanks to a positive psychological effect that makes the traffic seem farther away that it is, as the new field of psycho-acoustics has revealed.

Another option is to create a distraction by establishing a soothing continuous sound in the foreground, such as a fountain. (The sound of running water in one’s garden was particularly popular with the ancient Romans — maybe a reaction to the noisy carts in the street?)

How can I be a better recycler?

Stop putting plastic bags in your recycling bins. Representatives from both the Ulster County and Dutchess County resource recovery agencies said the bags are the biggest culprit in gumming up the machinery used to sort the recyclable plastic, metal, glass, paper and cardboard items. Plastic bags are a huge problem, which the counties might be better off banning. Bill Calogero, executive director at the Dutchess agency, said the bags are too lightweight to justify the cost of transfer, so they can’t be recycled. Ditto for Styrofoam peanuts and clamshells, which also should not be thrown in your bins.