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Jones AS, Marini J, Solo-Gabriele HM, Robey NM, Townsend TG. Arsenic, copper, and chromium from treated wood products in the U.S. disposal sector. WASTE MANAGEMENT (NEW YORK, N.Y.) 2019; 87:731-740. [PMID: 31109576 DOI: 10.1016/j.wasman.2019.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/23/2019] [Accepted: 03/03/2019] [Indexed: 05/20/2023]
Abstract
Construction and demolition (C&D) wood can be recycled as mulch for landscaping or cogeneration. Limitations to such recycling are dependent on metals concentrations in mulch (As, Cu, and Cr) from the inclusion of waterborne-preservative treated wood. The objective of this study was to evaluate the amount of waterborne-preservative treated wood (by wood volume and by mass of metal) that enters the C&D wood waste stream in the U.S. by utilizing a mass balance approach. A model was developed using wood treatment industry production statistics, estimated leaching rates of metal-based preservatives, and typical service lives of wood products. Outputs of the model indicate that the volumes of waterborne preservative treated wood disposed of may exceed 16 million m3 per year by 2030. The peak yearly metal mass disposed of corresponded to 18,400 metric tons for arsenic and 24,500 tons of chromium in 2013. Given the current trends in production, the mass of copper disposed of will increase to 20,900 tons by 2030. In order to meet regulatory guidelines regarding metals in recycled C&D wood, waterborne-preservative treated wood must be separated and removed. This separation mitigates environmental contamination from wood preservatives such as chromated copper arsenate (CCA).
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Affiliation(s)
- Athena S Jones
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL 33146-0630, USA.
| | - Juniper Marini
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL 33146-0630, USA.
| | - Helena M Solo-Gabriele
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL 33146-0630, USA.
| | - Nicole M Robey
- Department of Environmental Engineering Sciences, University of Florida, Gainesville, FL 32611-6450, USA.
| | - Timothy G Townsend
- Department of Environmental Engineering Sciences, University of Florida, Gainesville, FL 32611-6450, USA.
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Robey NM, Solo-Gabriele HM, Jones AS, Marini J, Townsend TG. Metals content of recycled construction and demolition wood before and after implementation of best management practices. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 242:1198-1205. [PMID: 30118908 DOI: 10.1016/j.envpol.2018.07.134] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 07/31/2018] [Accepted: 07/31/2018] [Indexed: 06/08/2023]
Abstract
A limitation to recycling wood from construction and demolition (C&D) waste is contamination of metals from the inadvertent inclusion of preservative treated wood, in particular wood treated with chromated copper arsenate (CCA) and newer copper-based formulations. To minimize contamination many regions have developed best management practices (BMPs) for separating treated from untreated wood. The objective of this study was to evaluate the fraction of preservative treated wood in recycled C&D wood after the implementation of BMPs, using Florida as a case study. Methods involved collecting recycled C&D wood samples from throughout the state, measuring metals concentrations (As, Cu, and Cr) in the samples to compute the fraction of recycled wood treated with waterborne wood preservatives, and comparing measurements with those taken prior to the formalization of BMPs. Metals concentrations were measured using two methods, one based on traditional laboratory digestion methods and another using a more rapid hand-held X-ray Fluorescence (XRF) device in the field. The proportion of waterborne preservative-treated wood in recycled wood products has reduced significantly in the intervening 20 years (from 6% to 2.9%), and the fraction of CCA-treated wood has been reduced even further, to 1.4%. The remaining fraction of waterborne preservative-treated wood is comprised of new formulations of copper-based preservatives. This suggests that restrictions from the wood preservation industry and best management practices implemented at recycling facilities have been effective in reducing heavy metal contamination from pressure treated lumber in recycled wood products.
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Affiliation(s)
- Nicole M Robey
- Department of Environmental Engineering Sciences, University of Florida, P.O. Box 116450, Gainesville, FL, 32611 - 6450, USA.
| | - Helena M Solo-Gabriele
- Department of Civil, Architectural and Environmental Engineering, University of Miami, P.O. Box 248294, Coral Gables, FL, 33146 - 0630, USA.
| | - Athena S Jones
- Department of Civil, Architectural and Environmental Engineering, University of Miami, P.O. Box 248294, Coral Gables, FL, 33146 - 0630, USA.
| | - Juniper Marini
- Department of Civil, Architectural and Environmental Engineering, University of Miami, P.O. Box 248294, Coral Gables, FL, 33146 - 0630, USA.
| | - Timothy G Townsend
- Department of Environmental Engineering Sciences, University of Florida, P.O. Box 116450, Gainesville, FL, 32611 - 6450, USA.
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Ferguson AC, Black JC, Sims IB, Welday JN, Elmir SM, Goff KF, Higginbotham JM, Solo-Gabriele HM. Risk Assessment for Children Exposed to Arsenic on Baseball Fields with Contaminated Fill Material. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15010067. [PMID: 29300352 PMCID: PMC5800166 DOI: 10.3390/ijerph15010067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 12/24/2017] [Accepted: 12/27/2017] [Indexed: 11/16/2022]
Abstract
Children can be exposed to arsenic through play areas which may have contaminated fill material from historic land use. The objective of the current study was to evaluate the risk to children who play and/or spend time at baseball fields with soils shown to have arsenic above background levels. Arsenic in soils at the study sites located in Miami, FL, USA showed distinct distributions between infield, outfield, and areas adjacent to the fields. Using best estimates of exposure factors for children baseball scenarios, results show that non-cancer risks depend most heavily upon the age of the person and the arsenic exposure level. For extreme exposure scenarios evaluated in this study, children from 1 to 2 years were at highest risk for non-cancer effects (Hazard Quotient, HQ > 2.4), and risks were higher for children exhibiting pica (HQ > 9.7) which shows the importance of testing fill for land use where children may play. At the study sites, concentration levels of arsenic resulted in a range of computed cancer risks that differed by a factor of 10. In these sites, the child’s play position also affected risk. Outfield players, with a lifetime exposure to these arsenic levels, could have 10 times more increased chance of experiencing cancers associated with arsenic (i.e., lung, bladder, skin) in comparison to infielders. The distinct concentration distributions observed between these portions of the baseball fields emphasize the need to delineate contaminated areas in public property where citizens may spend more free time. This study also showed a need for more tools to improve the risk estimates for child play activities. For instance, more refined measurements of exposure factors for intake (e.g., inhalation rates under rigorous play activities, hand to mouth rates), exposure frequency (i.e., time spent in various activities) and other exposure factors (e.g., soil particulate emission rates at baseball play fields) can help pinpoint risk on baseball fields where arsenic levels may be a concern.
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Affiliation(s)
- Alesia C Ferguson
- Environmental and Occupational Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
| | - Jennifer C Black
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL 33146, USA.
| | - Isaac B Sims
- Environmental and Occupational Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
| | - Jennifer N Welday
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL 33146, USA.
| | - Samir M Elmir
- Florida Department of Health at Miami-Dade County, Miami, FL 33056, USA.
| | - Kendra F Goff
- Florida Department of Health, Tallahassee, FL 32399, USA.
| | | | - Helena M Solo-Gabriele
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL 33146, USA.
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Gundupalli SP, Hait S, Thakur A. Multi-material classification of dry recyclables from municipal solid waste based on thermal imaging. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 70:13-21. [PMID: 28951147 DOI: 10.1016/j.wasman.2017.09.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 09/18/2017] [Accepted: 09/18/2017] [Indexed: 06/07/2023]
Abstract
There has been a significant rise in municipal solid waste (MSW) generation in the last few decades due to rapid urbanization and industrialization. Due to the lack of source segregation practice, a need for automated segregation of recyclables from MSW exists in the developing countries. This paper reports a thermal imaging based system for classifying useful recyclables from simulated MSW sample. Experimental results have demonstrated the possibility to use thermal imaging technique for classification and a robotic system for sorting of recyclables in a single process step. The reported classification system yields an accuracy in the range of 85-96% and is comparable with the existing single-material recyclable classification techniques. We believe that the reported thermal imaging based system can emerge as a viable and inexpensive large-scale classification-cum-sorting technology in recycling plants for processing MSW in developing countries.
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Affiliation(s)
- Sathish Paulraj Gundupalli
- Department of Mechanical Engineering, Indian Institute of Technology Patna, Bihta, Patna, Bihar 801103, India.
| | - Subrata Hait
- Department of Civil and Environmental Engineering, Indian Institute of Technology Patna, Bihta, Patna, Bihar 801103, India.
| | - Atul Thakur
- Department of Mechanical Engineering, Indian Institute of Technology Patna, Bihta, Patna, Bihar 801103, India.
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Vrancken C, Longhurst PJ, Wagland ST. Critical review of real-time methods for solid waste characterisation: Informing material recovery and fuel production. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 61:40-57. [PMID: 28139367 DOI: 10.1016/j.wasman.2017.01.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 12/16/2016] [Accepted: 01/15/2017] [Indexed: 06/06/2023]
Abstract
Waste management processes generally represent a significant loss of material, energy and economic resources, so legislation and financial incentives are being implemented to improve the recovery of these valuable resources whilst reducing contamination levels. Material recovery and waste derived fuels are potentially valuable options being pursued by industry, using mechanical and biological processes incorporating sensor and sorting technologies developed and optimised for recycling plants. In its current state, waste management presents similarities to other industries that could improve their efficiencies using process analytical technology tools. Existing sensor technologies could be used to measure critical waste characteristics, providing data required by existing legislation, potentially aiding waste treatment processes and assisting stakeholders in decision making. Optical technologies offer the most flexible solution to gather real-time information applicable to each of the waste mechanical and biological treatment processes used by industry. In particular, combinations of optical sensors in the visible and the near-infrared range from 800nm to 2500nm of the spectrum, and different mathematical techniques, are able to provide material information and fuel properties with typical performance levels between 80% and 90%. These sensors not only could be used to aid waste processes, but to provide most waste quality indicators required by existing legislation, whilst offering better tools to the stakeholders.
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Affiliation(s)
- C Vrancken
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK
| | - P J Longhurst
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK
| | - S T Wagland
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
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Gundupalli SP, Hait S, Thakur A. A review on automated sorting of source-separated municipal solid waste for recycling. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 60:56-74. [PMID: 27663707 DOI: 10.1016/j.wasman.2016.09.015] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 09/13/2016] [Accepted: 09/14/2016] [Indexed: 05/27/2023]
Abstract
A crucial prerequisite for recycling forming an integral part of municipal solid waste (MSW) management is sorting of useful materials from source-separated MSW. Researchers have been exploring automated sorting techniques to improve the overall efficiency of recycling process. This paper reviews recent advances in physical processes, sensors, and actuators used as well as control and autonomy related issues in the area of automated sorting and recycling of source-separated MSW. We believe that this paper will provide a comprehensive overview of the state of the art and will help future system designers in the area. In this paper, we also present research challenges in the field of automated waste sorting and recycling.
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Affiliation(s)
- Sathish Paulraj Gundupalli
- Department of Mechanical Engineering, Indian Institute of Technology Patna, Bihta, Patna, Bihar 801103, India.
| | - Subrata Hait
- Department of Civil and Environmental Engineering, Indian Institute of Technology Patna, Bihta, Patna, Bihar 801103, India.
| | - Atul Thakur
- Department of Mechanical Engineering, Indian Institute of Technology Patna, Bihta, Patna, Bihar 801103, India.
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Determination of Cu, Cr, and As in preserved wood (Eucalyptus sp.) using x-ray fluorescent spectrometry techniques. J Radioanal Nucl Chem 2015. [DOI: 10.1007/s10967-015-4669-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Tang Y, Gao W, Wang X, Ding S, An T, Xiao W, Wong MH, Zhang C. Variation of arsenic concentration on surfaces of in-service CCA-treated wood planks in a park and its influencing field factors. ENVIRONMENTAL MONITORING AND ASSESSMENT 2015; 187:4214. [PMID: 25512245 DOI: 10.1007/s10661-014-4214-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 12/01/2014] [Indexed: 06/04/2023]
Abstract
Wood preservatives can protect wood from dry rot, fungi, mould and insect damage, and chromated copper arsenate (CCA) has been used as an inorganic preservative for many years. However, wood treated with CCA has been restricted from residential uses in the EU from June 30, 2004, due to its potential toxicity. Such a regulation is not in place in China yet, and CCA-treated wood is widely used in public parks. A portable XRF analyser was used to investigate arsenic (As) concentration on surfaces of in-service CCA-treated wood planks in a popular park as well as the influencing field factors of age in-service, immersion and human footfall. With a total of 1207 readings, the observed As concentrations varied from below the detection limit (<10 mg/kg) to 15,746 mg/kg with a median of 1160 mg/kg. Strong variation of As concentrations were observed in different wood planks of the same age, on the surface of the same piece of wood, inside the same piece of wood, and different surfaces of walkway planks, hand rails and poles in the field. The oldest planks exhibited high As concentrations, which was related to its original treatment with high retention of CCA preservative. The effect of immersion in the field for about 4 months was insignificant for As concentration on the surfaces. However, a significant reduction of As was observed for immersion combined with human footfall (wiping by shoes). Human traffic in general caused slightly reduced and more evenly distributed As concentrations on the wood surfaces. The strong variation, slow aging and relatively weak immersion effects found in this study demonstrate that the in-service CCA-treated wood poses potential health risks to the park users, due to easy dermal contact especially when the wood is wet after rainfall. It is suggested that further comprehensive investigations and risk assessments of CCA-treated wood in residential areas in China are needed, and precautionary measures should be considered to reduce the potential risks to residents and visitors, especially children.
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Affiliation(s)
- Ya Tang
- Department of Environmental Sciences, School of Architecture and Environment, Sichuan University, Chengdu, Sichuan, 610065, China
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Hasan AR, Solo-Gabriele H, Townsend T. Online sorting of recovered wood waste by automated XRF-technology: part II. Sorting efficiencies. WASTE MANAGEMENT (NEW YORK, N.Y.) 2011; 31:695-704. [PMID: 21194917 DOI: 10.1016/j.wasman.2010.10.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 10/21/2010] [Accepted: 10/29/2010] [Indexed: 05/30/2023]
Abstract
Sorting of waste wood is an important process practiced at recycling facilities in order to detect and divert contaminants from recycled wood products. Contaminants of concern include arsenic, chromium and copper found in chemically preserved wood. The objective of this research was to evaluate the sorting efficiencies of both treated and untreated parts of the wood waste stream, and metal (As, Cr and Cu) mass recoveries by the use of automated X-ray fluorescence (XRF) systems. A full-scale system was used for experimentation. This unit consisted of an XRF-detection chamber mounted on the top of a conveyor and a pneumatic slide-way diverter which sorted wood into presumed treated and presumed untreated piles. A randomized block design was used to evaluate the operational conveyance parameters of the system, including wood feed rate and conveyor belt speed. Results indicated that online sorting efficiencies of waste wood by XRF technology were high based on number and weight of pieces (70-87% and 75-92% for treated wood and 66-97% and 68-96% for untreated wood, respectively). These sorting efficiencies achieved mass recovery for metals of 81-99% for As, 75-95% for Cu and 82-99% of Cr. The incorrect sorting of wood was attributed almost equally to deficiencies in the detection and conveyance/diversion systems. Even with its deficiencies, the system was capable of producing a recyclable portion that met residential soil quality levels established for Florida, for an infeed that contained 5% of treated wood.
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Affiliation(s)
- A Rasem Hasan
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL 33146-0630, USA
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Rasem Hasan A, Schindler J, Solo-Gabriele HM, Townsend TG. Online sorting of recovered wood waste by automated XRF-technology. Part I: detection of preservative-treated wood waste. WASTE MANAGEMENT (NEW YORK, N.Y.) 2011; 31:688-694. [PMID: 21186117 DOI: 10.1016/j.wasman.2010.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 10/04/2010] [Accepted: 11/10/2010] [Indexed: 05/30/2023]
Abstract
Waste wood is frequently contaminated with wood treatment preservatives including chromated copper arsenate (CCA) and alkaline copper quat (ACQ), both of which contain metals which contaminate recycled wood products. The objective of this research was to propose a design for online automated identification of As-based and Cu-based treated wood within the recovered wood waste stream utilizing an X-ray fluorescence (XRF) system, and to evaluate the detection parameters of such system. A full-scale detection unit was used for experimentation. Two main parameters (operational threshold (OT) and measurement time) were evaluated to optimize detection efficiencies. OTs of targeted metals, As and Cu, in wood were reduced to 0.02 and 0.05, respectively. The optimum minimum measurement time of 500 ms resulted in 98%, 91%, and 97% diversion of the As, Cu and Cr mass originally contained in wood, respectively. Comparisons with other detection methods show that XRF technology can potentially fulfill the need for cost-effective processing at large facilities (>30 tons per day) which require the removal of As-based preservatives from their wood waste stream.
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Affiliation(s)
- A Rasem Hasan
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL 33146, USA
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Janin A, Coudert L, Riche P, Mercier G, Cooper P, Blais JF. Application of a CCA-treated wood waste decontamination process to other copper-based preservative-treated wood after disposal. JOURNAL OF HAZARDOUS MATERIALS 2011; 186:1880-1887. [PMID: 21216528 DOI: 10.1016/j.jhazmat.2010.12.094] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Revised: 12/07/2010] [Accepted: 12/17/2010] [Indexed: 05/30/2023]
Abstract
Chromated copper arsenate (CCA)-treated wood was widely used until 2004 for residential and industrial applications. Since 2004, CCA was replaced by alternative copper preservatives such as alkaline copper quaternary (ACQ), copper azole (CA) and micronized copper quaternary (MCQ), for residential applications due to health concerns. Treated wood waste disposal is becoming an issue. Previous studies identified a chemical process for decontaminating CCA-treated wood waste based on sulfuric acid leaching. The potential application of this process to wood treated with the copper-based preservatives (alkaline copper quaternary (ACQ), copper azole (CA) and micronized copper quaternary (MCQ)) is investigated here. Three consecutive leaching steps with 0.1 M sulfuric acid at 75°C for 2 h were successful for all the types of treated wood and achieved more than 98% copper solubilisation. The different acidic leachates produced were successively treated by coagulation using ferric chloride and precipitation (pH=7) using sodium hydroxide. Between 94 and 99% of copper in leachates could be recovered by electrodeposition after 90 min using 2 A electrical current. Thus, the process previously developed for CCA-treated wood waste decontamination could be efficiently applied for CA-, ACQ- or MCQ-treated wood.
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Affiliation(s)
- Amélie Janin
- University of Toronto, Faculty of Forestry, 33, Willcocks St., Toronto, ON, M5S 3B3 Canada.
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Dubey B, Solo-Gabriele HM, Townsend TG. Quantities of arsenic-treated wood in demolition debris generated by Hurricane Katrina. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2007; 41:1533-6. [PMID: 17396637 PMCID: PMC2567428 DOI: 10.1021/es0622812] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The disaster debris from Hurricane Katrina is one of the largest in terms of volume and economic loss in American history. One of the major components of the demolition debris is wood waste of which a significant proportion is treated with preservatives, including preservatives containing arsenic. As a result of the large scale destruction of treated wood structures such as electrical poles, fences, decks, and homes a considerable amount of treated wood and consequently arsenic will be disposed as disaster debris. In this study an effort was made to estimate the quantity of arsenic disposed through demolition debris generated in the Louisiana and Mississippi area through Hurricane Katrina. Of the 72 million cubic meters of disaster debris generated, roughly 12 million cubic meters were in the form of construction and demolition wood resulting in an estimated 1740 metric tons of arsenic disposed. Management of disaster debris should consider the relatively large quantities of arsenic associated with pressure-treated wood.
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Affiliation(s)
- Brajesh Dubey
- Department of Environmental Engineering Sciences, University of Florida, PO Box 116450, Gainesville, Florida 32611-6450
| | - Helena M. Solo-Gabriele
- Department of Civil, Architectural and Environmental Engineering, University of Miami, Coral Gables, Florida 33124-0630
- Corresponding author phone: +1-305-284-2908; fax: +1-305-284-3492; e-mail:
| | - Timothy G. Townsend
- Department of Environmental Engineering Sciences, University of Florida, PO Box 116450, Gainesville, Florida 32611-6450
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