Hazard Remediation Research Articles

Synthesis of PAN Fibre-Supported Visible Light-Activated Carbon-Doped TiO<sub>2</sub> for Toluene Degradation of Interior Wall Paints

Polyacrylonitrile (PAN) fibre-supported carbon (C)-doped TiO2 (PCT) was fabricated by electrospinning C-doped TiO2/PAN/N,N-dimethylformamide mixtures. C doping was found to be a promising method for enabling visible photoactivation of TiO2 using graphite and PAN fibres as carriers. The fibrous PAN not only facilitated visible light-activated harvesting of TiO2 but also enabled the incorporation of C into the TiO2 lattice during the preparation process. Such composite fibres endowed TiO2 with high photocatalytic activity, and they were utilised to degrade toluene from interior wall paints with excitation at 440 nm. Given the maximum removal efficiency of 96.8% within 1 h, the developed photocatalysts can be considered to have paint hazard remediation properties.

Propagation network of tailings dam failure risk and the identification of key hazards

The tailings dam system is complex, and the dam structure changes continuously over time, which can make it difficult to identify key hazards of failure and characterize the accident formation process. To solve the above problems, based on complex network theory, the paper uses the identified hazards and the relationship between hazards to construct the propagation network of tailings dam failure risk (PNTDFR). The traditional analysis methods of network centrality usually focus on one aspect of the information of the network, while it cannot take into account to absorb the advantages of different methods, resulting in the difference between identified key nodes and real key hazards. To find the key hazards of tailing dam failure, based on the characteristics of multi-stage propagation of failure risk, the paper proposes a multi-stage collaborative hazard remediation method (MCHRM) to determine the importance of hazard nodes by absorbing the advantages of different centrality methods under different hazard remediation (deletion) ratios. The paper applies the above methods to Feijão Dam I. It can be found that when the priority remediation range is increased to 45%, the key hazards obtained by the MCHRM will cover all the causes of accidents proposed by the Dam I failure investigation expert group. Besides, the paper compares the monitoring data, daily inspection results and safety evaluation information of key hazards with the ‘Grading standards of hazard indicators’, and obtains the formation process of the Dam I failure and 30 key hazards in trigger state.

Oxidative removal of thallium(I) using Al beverage can waste with amendments of Fe: Tl speciation and removal mechanisms

The emerging occurrence of thallium (Tl) in environments arouses the imposition of effective technology for its remediation. Due to the low solubility of Tl(III), the oxidation-precipitation of Tl(I) is considered as an promising removal method. Here, we recycled Al beverage can powder (AlCP) as the substitute for zero-valent Al to conduct the Fenton-like reaction for Tl(I) oxidation and subsequently induced the Tl(III) precipitation via the alkalinization at pH 9.5. The Tl(I) removal mechanisms in AlCP systems with amendments of Fe(III) or Fe(II) were determined in relation to its speciation for both dissolved and solid phases. Results showed that although additions of Fe(III)/Fe(II) prompted the Tl(I) oxidation as compared with the pure AlCP system, they were detrimental to the Tl removal upon the alkalinization. While the greatest removal efficiency was ~ 92% in AlCP/Fe(III)/Fe(II) systems, up to 99.8% of total Tl could be removed from the pure AlCP system. The Tl-XANES data indicated that although Tl(III) dominated the Tl inventory (92 – 95%) on all solids collected upon the alkalinization, it preferred to precipitate as stable Tl2O3 in pure AlCP system but as labile Tl(III) in AlCP/Fe(III)/Fe(II) systems, which might sorb on precipitated Al (hydr)oxides. Such sorbed Tl(III) is subject to reduction and the further dissolution, accounting for the lower removal efficiency for Tl in the presence of Fe(III)/Fe(II). This study corroborated the comparable Tl(I) removal efficiency of AlCP to that of state-of-the-art (nano)composites, providing a niche opportunity to give consideration to both interests in hazard remediation and the waste reduction/reuse.

Summer rainstorm associated with a debris flow in the Amarilla gully affecting the international Agua Negra Pass (30°20′S), Argentina

Fil: Lauro, Carolina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mendoza. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales; Argentina

Predictive analysis of landslide susceptibility under climate change conditions — A study on the Chingshui River Watershed of Taiwan

Among the most critical issues, climatic abnormalities caused by global warming also affect Taiwan significantly for the past decade. The increasing frequency of extreme rainfall events, in which concentrated and intensive rainfalls generally cause geohazards including landslides and debris flows. Based on the rainfall data, this study employs rainfall frequency analysis together with the atmospheric general circulation model (AGCM) downscaling estimation to understand the temporal rainfall trends, distributions, and intensities in the Chingshui River watershed, a major watershed in central Taiwan. Rainfall estimates from the rainfall frequency analysis and AGCM were used in the susceptibility model to produce landslide susceptibility maps for various rainfall scenarios, including abnormal climate conditions. These results can be used for hazard remediation, mitigation, and prevention plans for the Chingshui River watershed.

Hazard remediation and recycling of tea industry and paper mill bottom ash through vermiconversion

Considerable amount of bottom ash (BA) is produced by tea and paper factories in Northeast India. This significantly deteriorates soil and surface water quality through rapid acidification, releasing sulfur compounds and heavy metals. The present investigation endeavoured to convert this waste to organic manure through vermicomposting by Eisenia fetida. Substantial increment in bioavailability of N, P, K, Fe, Mn and Zn along with remarkable decline in toxic metal like Cr due to vermicomposting was noteworthy. Furthermore, vermicomposted mixtures of Tea Factory BA (TFBA) or Paper Mill BA (PMBA) with organic matter (OM) attributed profuse pod yield of French Bean (Phaseolus vulgaris L.). Hence, bioconversion of TFBA and PMBA is highly feasible through vermicomposting and the converted materials can be utilized as potential organic fertilizer.

Public Health and Law Collaboration: The Philadelphia Lead Court Study

We determined whether Philadelphia Lead Court is effective in enforcing lead hazard remediation in the homes of children with elevated blood lead levels. We created a deidentified data set for properties with an initial failed home inspection (IFHI) for lead hazards from January 1, 1998, through December 31, 2008, and compared compliance rates within the first year and time to compliance for lead hazard remediation between 1998 and 2002 (precourt period) and between 2003 and 2008 (court period). We evaluated predictors of time to compliance. Within 1 year of the IFHI, 6.6% of the precourt and 76.8% of the court cases achieved compliance (P < .001) for the 3764 homes with data. Four years after the IFHI, 18% had attained compliance in the precourt period compared with 83.1% for the court period (P < .001). A proportional hazard analysis found that compliance was 8 times more likely in the court than the precourt period (P < .001). Lead court was more effective than precourt enforcement strategies. Most properties were remediated within 1 year of the IFHI, and time to compliance was significantly reduced. This model court could be replicated in other cities with similar enforcement problems.

HOME INJURY HAZARDS AND HOME INJURY IN NEW ZEALAND

BackgroundAlthough the home is a major setting for injury morbidity and mortality, there are few proven effective interventions for reducing home injury risk.AimsTo develop measurement protocols for assessing home injury...

Accidental Occupational Injuries to Endoscopy Personnel in a High-Volume Endoscopy Suite During the Last Decade: Mechanisms, Workplace Hazards, and Proposed Remediation

Scant data exist about accidental occupational injuries in endoscopy suites. This work systematically analyzes injuries, identifies workplace hazards, and proposes hazard remediation to potentially reduce risks. A retrospective study was performed on 14 previously unreported injuries among 120 endoscopy suite personnel in a high-volume endoscopy suite during 2000-2010, identified by medical records, employee records, and interviews. Injuries, mechanisms, outcomes, and workplace hazards were analyzed. Seventeen endoscopy personnel suffered occupational accidents in an endoscopy suite, including three previously reported cases of tripping on exposed wires (rate = 1.35/100 worker-years). The 14 newly reported accidents include: hand crushed against narrow doorway while transporting patients, 4; striking head against ceiling-mounted video monitors, 3; slip and fall on wet floor, 3; injury while breaking patient's fall, 2; injury while turning patient during colonoscopy, 1; and tripping over misplaced wheelchair, 1. Injuries included: hand-crush injury, 4; myofascial back strain, 2; scalp laceration, 2; knee contusion, 2; and other, 4 (mean = 6.1 ± 15.5 lost workdays, 6.1 ± 10.1 restricted workdays). Two gastroenterologists suffered a torn tendon or coccyx fracture from slip and falls while working in the hospital. Proposed hazard remediation includes: replace bulky, heavy CRT video monitors with sleek, light LCD-flat-panel-screens to reduce likelihood and impact of head collisions; eliminate sharp edges on video monitor supports; widen doorways to accommodate extra-wide stretchers; slip-resistant flooring for rooms with frequent liquid spills; and parking wheelchairs away from traffic areas. Potentially correctable design flaws may frequently contribute to accidents in endoscopy suites, including: bulky overhead video monitors, too narrow doors for extra-wide stretchers, absence of slip-resistant flooring, and wires exposed above the floor.

Legislation without Implementation: Mandatory Lead Paint Hazard Inspection and Remediation of Housing Rented in New Jersey

This article examines the current legislative and administrative scheme for the regulation of lead hazards in houses rented or sold in New Jersey, and makes comparisons with Massachusetts' statutory scheme. This article also investigates other states' attempts to achieve prevention of residential lead poisoning. This article ultimately proposes that to effectuate the goals of its lead prevention legislation, New Jersey should implement surveillance systems and standardized procedures to ensure that housing is properly inspected and remediated for lead hazards prior to issuing certificates of occupancy of rental homes.

Magnetic Response of Clustered UXO Targets

The objective of many recent UXO surveys has been described as “wide-area assessment” with the purpose of obtaining better definition of a known problem area. The targets of interest are clusters of ordnance, fragments and debris which are all indicators of greater contamination, higher risk of UXO hazard and higher remediation or construction costs. This is a different problem from the detection and discrimination of individual anomalies. This paper provides a definition of a “cluster” based on the amount of overlap between individual dipole signatures. In total field surveys, magnetic anomalies overlap significantly and show an increased amplitude response once the individual sources are spaced closer than 0.5 times the sensor height. When this condition is extended over a large area, such as the center of a target site, the result can be comparable to a horizontal sheet of dipoles. The equations to simulate a horizontal sheet are derived, and from these the relative density of targets may be calculated from the measured data by assuming a nominal target moment. Two field tests support both the qualitative and quantitative predictions. Extending this concept to field practice, we examine some of the implications for standard operational procedures. For example, if we accept that QA/QC metrics should represent the targets of interest, then we should require wide-area assessment surveys to create impractically large grids of surface frag. Likewise, for detection of clusters the concepts of detection probability and search radius based on single items are irrelevant. Discrimination techniques that rely on dipole fitting will be extremely inaccurate. Instead, QA parameters and models suitable for horizontal sheets will have to be derived.

Environmental and social impacts of electricity utilization: broadening the debate

Exposure of small laboratory animals to power-frequency high-voltage electric fields was reported to have endocrinological effects, including changes in pineal melatonin levels. It has been assumed that these results are directly attributable to electric-field effects, but this article suggests that air ionization, produced by corona activity at the animals’ body surfaces, may have been biologically active and could be relevant to the interpretation of some epidemiological and other studies. Although presently a matter of dispute, there is evidence that atmospheric ionization may be biologically active and could provide an alternative explanation for at least some apparent electromagnetic field interactions with biological subjects. Consideration of the electricity utilization environment as a whole, rather than one selected component, could allow the introduction of lower-cost, precautionary and putative hazard remediation measures.

Environmental Applications of Sub-Audio Magnetics

Sub-Audio Magnetics (SAM) is a method by which a total-field magnetic sensor may be used to simultaneously acquire both total magnetic intensity (TMI) and total-field electromagnetic induction (TFEMI) responses from buried metal. In situations where public safety is involved, regulators, such as the U.S. Environmental Protection Agency, can mandate the use of both magnetic and electromagnetic sensors for the detection of potentially hazardous items such as unexploded ordnance (UXO) and metal drums. SAM has now completed a program of evaluation and certification as a state-of-the-art technology, acceptable for application in the litigation-sensitive environmental hazard remediation market.During its certification program, SAM was applied to controlled U.S. test sites at the Aberdeen Proving Ground, Maryland, McKinley Range, Alabama, Waikoloa, Hawaii, and at the Newholme facility in Australia. It was also applied to situations in Montana where live UXO was present. In these demonstrations, a direct comparison was made between SAM results and common, state-of-the-art alternative geophysical detecting technologies. Based on demonstrations at these sites, it has been possible to quantify the key performance parameters: level of effort, detection performance as a function of depth and target size, false-alarm rejection achieved through dual-mode sensing, and the cost-benefit ratio of SAM compared with contemporary sensor technologies such as the Geonics EM61 and EM63 electromagnetic detectors, and G-tek’s TM-5EMU electromagnetic detector and TM-4 total field magnetometer.SAM has proven to be very successful in detecting a wide range of metallic UXO items to depths exceeding achievable detection by all contemporary sensors. In the Montana live sites, where the smallest item of UXO was a 76 mm projectile, false-alarm rates were reduced from 7 per UXO, using TMI only, to 0.7 per UXO using combined SAM TMI and TFEMI data, without diminishing the probability of UXO detection. Survey cost per hectare using SAM was determined to be less than one quarter that of conducting TMI plus EMI surveys separately.The application of SAM to extremely magnetic lava flows at Waikoloa in Hawaii showed that SAM cannot yet compete with the ground-balancing capability of the TM-5EMU in this environment. Advanced signal-processing development may reduce this present limitation.

Using Historical Documents for Landslide, Debris Flow and Stream Flood Prevention. Applications in Northern Italy

Landslides, debris flows and stream floods are common natural processes inNorthern Italy. Their occurrence can be correctly assessed in space and timeonly through a sound basis of knowledge acquired by the scientific use of alarge number of historical documents. Over the last 30 years, the CNR IRPIInstitute of Turin has made archive data utilisation one of its main points ofscientific research, through the collection of hundreds of thousands of recordscontained in published and unpublished documents and historical reports onnatural damaging events over the last 500 years, particularly since XIX Century. The historical data, interpreted and selected on a scientific basis, have beenorganised in a database and utilised for landscape planning and hydrogeologicalprevention. In co-operation with public organisations, the IRPI Institute hassupplied information (type, location, magnitude, frequency and effects) abouthazardous events in Northern Italy. To give an example, in the last 4 yearsabout 4,500 failure events have been detected along the road network of theTurin Province and many debris flow, rockfall, landslide and flood events inthe Lombardy Region. These data are reported as points linked to the relevantevent-card on technical cartography (scale 1:10,000 or 1:25,000), so that theycan be immediately utilised either on paper or digitally (e.g., GIS, Arcview software). The present day elaboration of archival data permit the possible analytical applications for structural interventions in natural hazard remediation in built-up areas. In all cases, the results of research allow public awareness of natural danger and the correct layout of civil protection strategies.

The effect of lead-based paint hazard remediation on blood lead levels of lead poisoned children in New York City

Despite the widespread use of lead paint hazard control for children with lead poisoning, few controlled studies that estimate the effect of such control on children's blood lead levels have been published. This retrospective follow-up study examined the effects of lead hazard remediation and its timing on the blood lead levels of lead-poisoned children. From the New York City child blood lead registry, 221 children were selected who had an initial blood lead level of 20–44μg/dL between 1 July 1994 and 31 December 1996; were 6 months to 6 years of age; had a report of a follow-up blood lead test between 10 and 14 months after the initial test; had a lead-based paint hazard identified in the primary dwelling unit prior to the 10- to 14-month follow-up blood lead test; had resided or spent time at only one address with an identified lead-based paint hazard; and were not chelated. The decline in geometric mean blood lead levels from baseline to 10–14 months later was compared for children whose homes were remediated and whose homes were not remediated during the follow-up period. Regardless of remediation, geometric mean blood lead levels declined significantly from 24.3μg/dL at the initial diagnosis to 12.3μg/dL at the 10- to 14-month follow-up blood lead test (P<0.01). Among the 146 children whose homes were remediated the geometric mean blood lead levels declined 53% compared to 41% among the 75 children whose homes were not remediated by the follow-up blood lead test, a remediation effect of approximately 20% (P<0.01). After adjusting for potential confounders, the remediation effect was 11%, although it was no longer significant. Race was the only factor that appeared to confound the relationship: Black children had higher follow-up blood lead levels even after controlling for other factors, including the natural logarithm of the initial blood lead level. The effect of remediation appeared to be stronger for younger (10 to <36 months old) than for older (36 to 72 months old) children (P=0.06). While children in homes with earlier remediation (within less than 3 months) appeared to have greater declines in blood lead levels at the follow-up test than children in homes with later remediation (after 3 or more months), this trend was not significant when controlling for confounding factors. The findings of this study suggest that early identification of lead-poisoned children and timely investigation and abatement of hazards contribute to reducing blood lead levels. However, the apparent effect is modest and further research is needed to systematically test and improve the effectiveness of lead hazard controls.

Prevention of childhood lead poisoning.

Although past national public health efforts have reduced lead exposure significantly, lead poisoning remains the most common environmental health problem affecting American children. Currently, lead exposure occurs predominantly through ingestion of lead-contaminated household dust and soil in older housing containing lead-based paint; exposure can be increased with housing deterioration or renovation. Environmental prevention efforts focus on improvement in risk assessment, development of housing-based standards for lead-based paint hazards, and safe and cost-effective lead hazard remediation techniques. Educational efforts address parental awareness of lead exposure pathways, hygiene, and housekeeping measures to prevent ingestion of dust and soil. Blood lead screening is recommended either universally at ages 1 and 2 years or in a targeted manner where local health departments can document a low prevalence of elevated blood lead levels. Nutritional interventions involve provision of regular meals containing adequate amounts of calcium and iron and supplementation for iron deficiency. Lead chelation should complement environmental, nutritional, and educational interventions, when indicated. Collaboration of multiple federal agencies in a new strategy to eliminate childhood lead poisoning should further prevention efforts.

Residential lead-based-paint hazard remediation and soil lead abatement: their impact among children with mildly elevated blood lead levels.

This prospective study describes the impact of residential lead-based-paint hazard remediations on children with mildly elevated blood lead levels. Changes in blood lead levels were observed following paint hazard remediation alone and in combination with soil abatement. After adjustment for the confounding variables paint hazard remediation alone was associated with a blood lead increase of 6.5 micrograms/dL (P = 0.5), and paint hazard remediation combined with soil abatement was associated with an increase of 0.9 microgram/dL (P = 36). Lead-based-paint hazard remediation as performed in this study, is not an effective secondary prevention strategy among children with mildly elevated blood lead levels.

Retrospective study of the impact of lead-based paint hazard remediation on children's blood lead levels in St. Louis, Missouri.

A retrospective follow-up study was conducted to evaluate the effectiveness of lead-based paint hazard remediation in reducing children's blood lead levels. The authors reviewed existing St. Louis, Missouri, City Health Department records, identified 185 children younger than age 6 years who had blood lead levels > or = 25 micrograms/dl during 1989 or 1990, and compared changes in blood lead levels among children whose dwellings did and those whose dwellings did not undergo remediation. Among 54 children who had not moved or received chelation therapy and whose blood lead levels were measured 10-14 months after diagnosis, the geometric mean blood lead level decreased 23% among children living in remediated dwellings (n = 37) and 12% among children in nonremediated dwellings (n = 17) (p = 0.07, t test). The estimated size of the remediation effect was similar using multiple regression (-13%; 95% confidence interval (CI) -25 to 1; p = 0.06) and an approach based on generalized estimating equations (-16%, 95% CI -25 to -7; p = 0.002), when adjusted for covariates. The effect of remediation was greater among children whose blood lead levels at diagnosis were > or = 35 micrograms/dl (-22%) than among those whose blood lead levels at diagnosis were between 25 and 34 micrograms/dl (-1%). Among lead-poisoned children in St. Louis, children whose dwellings undergo lead-based paint hazard remediation have a greater decline in geometric mean blood lead level than do children whose dwellings do not, but the effect of remediation may be influenced by the blood lead level at diagnosis.

SELF‐ADMINISTERED WRITTEN PROMPTS TO TEACH HOME ACCIDENT PREVENTION SKILLS TO ADULTS WITH BRAIN INJURIES

This study evaluated the use of written checklists and task analyses as self-administered prompts to teach home accident prevention skills to 4 adults with brain injuries. Subsequent to baseline, participants used written checklists that identified potential in-home hazards but did not prompt behaviors necessary for hazard remediation. Written individualized task analyses, incorporating specific behavioral steps for correcting hazards that participants had failed to remediate during the checklist phase, were used to prompt appropriate responding when necessary. These were subsequently faded to transfer stimulus control to the natural conditions. A multiple probe technique across participants and settings was used. Results indicated that the checklist alone was sufficient to increase appropriate responses to many of the potential hazards. Individualized task analyses, when needed, resulted in appropriate remediation of all potential hazards. Generalization to untrained potential hazards occurred to some degree for all participants. Follow-up results showed that most skills trained were maintained over a 1-month period.