Craig A. McKinstry

Development of an Environmental Relative Moldiness Index for Us Homes

Objective: The objective of this study was to establish a national relative moldiness index for homes in the United States. Methods: As part of the Housing and Urban Developments American Healthy Homes Survey, dust samples were collected by vacuuming 2 m2 in the bedrooms plus 2 m2 in the living rooms from a nationally representative 1096 homes in the United States using the Mitest sampler. Five milligrams of sieved (300 &mgr;m pore, nylon mesh) dust was analyzed by mold-specific quantitative polymerase chain reaction for the 36 indicator species in 1096 samples. Results: On the basis of this standardized national sampling and analysis, an “Environmental Relative Moldiness Index” was created with values ranging from about −10 to 20 or above (lowest to highest). Conclusions: The Environmental Relative Moldiness Index scale may be useful for home mold-burden estimates in epidemiological studies.

Relative moldiness index as predictor of childhood respiratory illness.

The results of a traditional visual mold inspection were compared to a mold evaluation based on the Relative Moldiness Index (RMI). The RMI is calculated from mold-specific quantitative PCR (MSQPCR) measurements of the concentration of 36 species of molds in floor dust samples. These two prospective mold evaluations were used to classify the mold condition in 271 homes of infants. Later, the development of respiratory illness was measured in the infants living in these homes and the predictive value of each classification system was evaluated.The binary classification of homes as either moldy or non-moldy by on-site visual home inspection was not predictive of the development of respiratory illness (wheeze and/or rhinitis) (P=0.27). Conversely, a method developed and validated in this paper, using the RMI index fit to a logistic function, can be used to predict the occurrence of illness in homes and allows stake-holders the choice among various levels of risk.

Higher Environmental Relative Moldiness Index (ERMIsm) values measured in Detroit homes of severely asthmatic children.

Sieved vacuum bag dust from the homes of 143 children in Detroit was analyzed by mold specific quantitative PCR (MSQPCR) and the Environmental Relative Moldiness Index (ERMIsm) was calculated for each home. Children living in these homes were grouped as non-asthmatic (n=83), moderately asthmatic (n=28) and severely asthmatic (n=32) based on prescription medication usage for their asthma management (none, occasional and daily, respectively). The mean ERMI for each group of homes was 6.2 for non-asthmatic, 6.3 for moderately asthmatic and 8.2 for severely asthmatic children. The ERMI values in the homes of severely asthmatic children were significantly greater compared to the non-asthmatics (p=0.04 in Wilcoxon Rank-sum test). Aspergillus niger and Aspergillus unguis were the primary mold species that distinguished severely asthmatic childrens homes and non-asthmatic childrens homes (p<0.05; Wilcoxon Rank-sum test). The determination of the homes ERMI values may aid in prioritizing home remediation efforts, particularly in those children who are at increased risk for asthma exacerbation.

Correlation between ERMI Values and Other Moisture and Mold Assessments of Homes in the American Healthy Homes Survey

The main objective of this study was to evaluate the correlation between the Environmental Relative Moldiness Index (ERMI) values in the Department of Housing and Urban Development American Healthy Homes Survey (AHHS) homes and an alternative analysis frequently used in mold investigations, i.e., the inspector’s “walk-through” assessment of visual or olfactory evidence of mold combined with occupant’s answers to a questionnaire about mold odors and moisture. Homes in the highest ERMI quartile were in agreement with visual inspection and/or occupant assessment 48% of the time but failed to detect the mold in 52% of the fourth quartile homes. In about 7% of lowest ERMI quartile homes, the inspection and occupant assessments overestimated the mold problem. The ERMI analysis of dust from homes may be useful in finding hidden mold problems. An additional objective was to compare the ERMI values in inner city east-Baltimore homes, where childhood asthma is common, to the AHHS randomly selected homes.

Derivation of Mortal Injury Metric for Studies of Rapid Decompression of Depth-Acclimated Physostomous Fish

In 2005 the U.S. Army Corps of Engineers (USACE) began a study to investigate the response of hatchery and run-of-the-river (ROR) juvenile Chinook salmon to the effects of rapid decompression during passage through mainstem Federal Columbia River Power System (FCRPS) Kaplan turbines. In laboratory studies conducted by Pacific Northwest National Laboratory (PNNL) for USACE since 2005, juvenile fish have been exposed to rapid decompression in a barometric pressure chamber. An initial study considered the response of juvenile Chinook salmon bearing radio transmitters to rapid decompression resulting from exposure to a pressure time history simulating the worst case condition that might be experienced during passage through an operating turbine. The study in 2005 found that acclimation depth was a very important treatment factor that greatly influenced the significantly higher incidence of injury and mortality of rapidly decompressed Chinook salmon bearing radio telemetry devices. In 2006 we initiated a statistical investigation using data in hand into derivation of a new end-point measure for assessment of the physiological response of juvenile Chinook salmon to rapid decompression. Our goal was a measure that would more fully utilize both mortality and injury data while providing a better assessment of the most likely survival outcome for juvenile physostomous fish exposed to rapid decompression. The conclusion of the analysis process was to classify fish as mortally injured when any of the 8 injuries are present, regardless of whether the fish was last observed alive or not. The mortally injured classification has replaced mortality as the end point metric for our rapid decompression studies. The process described in this report is an example of how a data set may be analyzed to identify decision criterion for objective classification of test fish to a specific end-point. The resulting list of 8 mortal injuries is applicable to assess injuries from rapid decompression and is currently being applied to ongoing studies. We intend to update this analysis as more data becomes available and to extend it to ROR Chinook salmon smolt. The method itself is applicable to other injury and mortality data for juvenile salmonids from laboratory and field studies related to all dam passage routes and for collision, strike, and shear injuries in addition to decompression.

Fall Chinook Salmon Spawning Activity Versus Daylight and Flow in the Tailrace of a Large Hydroelectric Dam

Abstract We deployed an acoustic system during the spawning season for fall Chinook salmon Oncorhynchus tshawytscha in 2001 to determine whether fall Chinook salmon spawning activity in a hydroelectric dam tailrace area was affected by daylight or river flow. Our study design allocated sampling effort nearly equally between hours of darkness and hours of daylight throughout each 24-h period. The acoustic system recorded sounds of fall Chinook salmon spawning activity in two index areas downstream of Wanapum Dam on the Columbia River in Washington State. One index area was a deepwater spawning site located in 9–11 m of water. The other index area was a moderate-depth midchannel bar, where water depths ranged from 2.5 to 6 m. We defined the rate of spawning activity in digs per minute. Fall Chinook salmon spawning activity rates in the Wanapum Dam tailrace were influenced by both daylight and river discharge, which had a pronounced nonlinear effect on spawning activity rates. To account for nonlinearity, a ...

Screening Tools to Estimate Mold Burdens in Homes

Objective: The objective of this study was to develop screening tools that could be used to estimate the mold burden in a home which would indicate whether more detailed testing might be useful. Methods: Two possible screening methods were considered for mold analysis: use of vacuum cleaner bag dust rather than the standard protocol dust samples and reducing the number of molds needed to be quantified resulting in the creation of an alternative mold burden scale. Results: Vacuum bag dust analysis placed the estimate of mold burden into the upper or lower half of the Environmental Relative Moldiness Index scale. Mold burdens estimated by only 12 species produced an index, the American Relative Moldiness Index, with a correlation of &rgr; = 0.80 with the Environmental Relative Moldiness Index. Conclusions: Two screening tools were developed for estimating the mold burden in homes.

Prediction of power system balancing requirement and tail event

This paper presents a methodology for the prediction of power system balancing requirement and the probability of tail event (large imbalance between generation and load). Maintaining sufficient balancing reserves to match the difference between hourly generation schedule and real-time variable load and intermittent resources becomes more and more challenging with the increasing penetration of intermittent energy sources. The presented methodology uses yearly distributions and hourly distributions of balancing requirement and tail events to provide a high level look at the issue and warn system operators of those hours when problems are most likely to occur. For real-time prediction, a Bayes net model is constructed to model the statistical relationships between system imbalance and forecast errors, generation schedule control errors and other influential factors. The methodology will be able to provide reference information to system operators in determining the sufficiency of system balancing reserve and taking appropriate control actions.

Evaluating virulence of waterborne and clinical Aeromonas isolates using gene expression and mortality in neonatal mice followed by assessing cell culture’s ability to predict virulence based on transcriptional response

Aims:  To assess the virulence of Aeromonas spp. using two models, a neonatal mouse assay and a mouse intestinal cell culture.

Low Probability Tail Event Analysis and Mitigation in the BPA Control Area

This report investigated the uncertainties with the operations of the power system and their contributions to tail events, especially under high penetration of wind. A Bayesian network model is established to quantify the impact of these uncertainties on system imbalance. The framework is presented for a decision support tool, which can help system operators better estimate the need for balancing reserves and prepare for tail events.