BIOAVAILABILITY OF HEAVY METALS IN PRESSURE TREATED WOOD

加压处理木材中重金属的生物利用度

• 批准号: 2608520
• 负责人: Terry Gordon
• 金额: $ 22.15万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-12-15 至 1998-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2608520
• 关键词: arsenic; chemical binding; chromium; copper; crosslink; dust; environmental toxicology; laboratory rat; lung injury; pesticide biological effect; pesticides; phagocytes; tissue /cell culture; toxin metabolism

(Adapted from the Investigator~s Abstract): To prolong the life of wood used in the construction industry, toxic chemical have been used since the 1930's to impregnate and protect the wood. These chemicals have been highly successful in protecting wood against termites, other insects, fungus, and rot. Nearly 300 million cubic feet of pressure- treated wood are reduced and used each year. The most common chemical treatment is the impregnation of the wood with chromated copper arsenate (CCA). Although these metals possess a wide range of toxic properties, the U.S. EPA ruled in 1984 that CCA pressure- treated wood is safe for interior use, play structures, garden edging, and vegetable stakes. This ruling was based on the tight,'irreversible' binding of the metals to the wood fibers as reported by the trade association of pressure-treated wood manufacturers. Although small amounts of the metals are extracted in aqueous solutions common to fresh and salt water environments, no research efforts has examined the bio-availability of these metals upon inhalation of the airborne wood particles generated at construction sites. This research proposal will examine the bioavailability of these metals after the CCA wood encounters, and is processed by, phagocytic cells. The hypothesis is that the hostile intracellular environment of phagocytic cells (e.g., vacuoles containing proteolytic enzymes and increased acidity) will release the toxic metals bound to the wood fibers. This hypothesis will be examined by studying the ability of pressure-treated wood dust to induce: 1) cytotoxicity in arsenic-sensitive cells (arsenic bio- availability); 2) metallothionein (arsenic and copper bio-availability); and 3) DNA-protein crosslinks (chromium bio-availability) in phagocytic cells. Observation of positive findings in the these endpoints would provide direct evidence that the intracellular environment of phagocytic cell is able to reverse the ~irreversible~ nature of the heavy metal binding to wood fibers and thus, suggest that inhalation of pressure-treated wood dust poses an occupational hazard.

（改编自调查员摘要）：延长木材的寿命 自从建筑行业中使用，有毒化学物质已被使用 1930年代浸渍和保护木材。 这些化学物质具有 在保护木材免受白蚁的保护方面非常成功，其他 昆虫，真菌和腐烂。 近3亿立方英尺的压力 - 每年都会减少处理的木材。 最常见的 化学处理是木材的浸渍 铜砷（CCA）。 尽管这些金属范围很广 在有毒特性中，美国EPA在1984年裁定CCA压力 处理的木材安全可用于室内使用，游戏结构，花园边缘， 和蔬菜赌注。 该裁决是基于紧密的“不可逆” 贸易报告的金属对木纤维的结合 经过压力处理的木材制造商协会。虽然很小 在共有的水溶液中提取的金属量 新鲜和盐水环境，没有研究工作研究 这些金属吸入空气木的生物可用性 在施工地点产生的颗粒。 这项研究建议将 检查CCA木材后这些金属的生物利用度 相遇，并由吞噬细胞处理。该假设是 吞噬细胞的敌对细胞内环境（例如 含有蛋白水解酶的液泡和酸度增加）将 释放与木纤维结合的有毒金属。 这个假设将会 通过研究压力处理的木尘的能力来检查 诱导：1）砷敏感细胞的细胞毒性（砷生物 - 可用性）; 2）金属硫蛋白（砷和铜生物可用性）； 3）DNA-蛋白交联（铬生物利用度） 吞噬细胞。 观察这些积极发现 终点将提供直接证据表明细胞内 吞噬细胞的环境能够扭转不可逆的〜 重金属结合与木纤维的性质，因此表明 吸入压力处理的木尘会带来职业危害。