Cu)-based pesticides, with exceptions for certain industrial uses. And, due to this phase-out of arsenic preservatives, Cu-based preservatives are expected to dominate the residential treated wood market. Arsenic, chromium (Cr) and copper from the treated wood can be released to the environment or indirectly routed to humans by many different mechanisms, including direct touching of wood, the inhaling of wood dust during cutting, or through contamination of water and soil by leachates produced when the wood is in contact with rainfall and moisture. Each of these three elements has negative impacts on the environment and human health, and each is characterized by different toxicity levels to targeted species. In some cases, treated wood is inadvertently recycled as mulch or as fuel for the production of energy. These recovered forms of treated wood are believed to leach metals more quickly and thus efforts are needed to avoid contamination of recycled wood with treated wood. The research Over the last decade, numerous studies conducted by researchers with the University of Florida and the University of Miami, Coral Gables, have looked to uncover the environmental impacts of using, and disposing of, pressure-treated wood products. The focus of these projects I t's resistant to decay and annoying insects. Suitable for countless ground and non-ground-contact applications, such as decking, fencing, sills, railings, joists, posts, wood foundations, building poles, retaining and pilings; it can also last as much as 10-to 20-times longer than untreated lumber. However, unlike regular wood, which has an abundance of post-consumer end-uses, pressure-treated wood can only be reused in specific post-consumer applications, including use as aggregate particles in concrete, in some forms of commercial landscaping, as agricultural fencing, or as a raw material in the manufacture of such wood materials as particleboard. Treated wood manufactured throughout North America, as well as in other countries, is produced by impregnating the timber with certain pesticides, and can be done via numerous processes, including brushing, spraying, dipping, soaking, steeping or by means of hot and cold bath. The most notable process for protecting wood from biological deterioration, however, involves the pressurized injection of pesticides into the wood – giving the lumber a retention level between 0.25 to 2.5 pounds of preservative per cubic foot of wood. Historically, the most common preservative utilized for such processes was arsenic (As)-based chromated copper arsenate (CCA). However, at the end of 2003, the wood treatment industry, in a voluntary agreement with the U.S. Environmental Protection Agency, stopped treating residential lumber with CCA, and began to phase out Knock on wood

العنوان

Dataset · May 2009

الناشر

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بلد الناشر

فلسطين

نوع المنشور

Both (Printed and Online)

المجلد

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السنة

2009

الصفحات

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