24. Indoor Air pollution 室内空气污染
① Priscilla Ouchida's "energy-efficient"house turned out to be a horrible dream.When she and her engineer husband married,they built a $100,000,three bedroom home in California.Tightly sealed to prevent air leaks,the house was equipped with small double-paned windows and several other energy-saving features.Problem began as soon as the couple moved in,however,Priscilla's eyes burned.Her throat was constantly dry.She suffer from headaches and could hardly sleep.It was as though she had suddenly developed a strange illness.
② Experts finally traced the cause of her illness.The level of formaldehyde gas in her kitchen was twice the maximum allowed by federal standards for chemical workers.The source of the gas ? Her new kitchen cabinets and wall-to-wall carpeting.
③The Ouchidas are victims of indoor air pollution,which is not given sufficient attention partly because of the nation's drive to save energy.The problem itself isn't new."The indoor environment was dirty long before energy conservation came alone,"says a pollution scientist in Maryland."Energy conservation has tended to worsen the situation in some case.
④ The problem appears to be more troublesome in newly constructed homes rather than old ones.Back in the days when energy was cheap,home builder didn't worry much about unsealed cracks.Because of such leaks,the air in an average home was replaced by fresh outdoor air about once an hour.As a result,the pollutants generated in most households seldom built up to dangerous levels.
