14 research outputs found
High levels of sewage contamination released from urban areas after storm events: A quantitative survey with sewage specific bacterial indicators
Background
Past studies have demonstrated an association between waterborne disease and heavy precipitation, and climate change is predicted to increase the frequency of these types of intense storm events in some parts of the United States. In this study, we examined the linkage between rainfall and sewage contamination of urban waterways and quantified the amount of sewage released from a major urban area under different hydrologic conditions to identify conditions that increase human risk of exposure to sewage.
Methods and findings
Rain events and low-flow periods were intensively sampled to quantify loads of sewage based on two genetic markers for human-associated indicator bacteria (human Bacteroides and Lachnospiraceae). Samples were collected at a Lake Michigan estuary and at three river locations immediately upstream. Concentrations of indicators were analyzed using quantitative polymerase chain reaction (qPCR), and loads were calculated from streamflow data collected at each location. Human-associated indicators were found during periods of low flow, and loads increased one to two orders of magnitude during rain events from stormwater discharges contaminated with sewage. Combined sewer overflow (CSO) events increased concentrations and loads of human-associated indicators an order of magnitude greater than heavy rainfall events without CSO influence. Human-associated indicator yields (load per km2 of land per day) were related to the degree of urbanization in each watershed. Contamination in surface waters were at levels above the acceptable risk for recreational use. Further, evidence of sewage exfiltration from pipes threatens drinking water distribution systems and source water. While this study clearly demonstrates widespread sewage contamination released from urban areas, a limitation of this study is understanding human exposure and illness rates, which are dependent on multiple factors, and gaps in our knowledge of the ultimate health outcomes.
Conclusions
With the prediction of more intense rain events in certain regions due to climate change, sewer overflows and contamination from failing sewer infrastructure may increase, resulting in increases in waterborne pathogen burdens in waterways. These findings quantify hazards in exposure pathways from rain events and illustrate the additional stress that climate change may have on urban water systems. This information could be used to prioritize efforts to invest in failing sewer infrastructure and create appropriate goals to address the health concerns posed by sewage contamination from urban areas
Use of time in chronic obstructive pulmonary disease: Longitudinal associations with symptoms and quality of life using a compositional analysis approach.
Background and objectivesThis study explored whether, for people with chronic obstructive pulmonary disease (COPD), changes to the 24-hour composition of physical activity (PA), sedentary behaviour (SB) and sleep were associated with changes in symptoms and health-related quality of life (HRQoL); and how time re-allocations between these behaviours were associated with changes in outcomes.MethodsThis study pools data on people with COPD drawn from two previous studies: a randomised controlled trial of cognitive behavioural therapy and pulmonary rehabilitation and a usual care cohort. Participants recalled behaviours and completed symptom and HRQoL assessments at baseline (T0) and four months (T1). Linear mixed-effects models (pooled control/intervention samples) predicted changes in outcomes from T0 to T1 with a change to the 24-hour behaviour composition; compositional isotemporal substitution predicted change in outcomes when re-allocating time between behaviours.ResultsValid data were obtained for 95 participants (forced expiratory volume in one second %predicted = 49.6±15.3) at T0 and T1. A change in the 24-hour behaviour composition was associated with a change in anxiety (pConclusionTo improve the overall health and wellbeing of people with COPD, intervention approaches that optimise the composition of PA, SB and sleep may be beneficial
Improving physical activity, sedentary behaviour and sleep in COPD: perspectives of people with COPD and experts via a Delphi approach
Background Little is known about how to achieve enduring improvements in physical activity (PA), sedentary behaviour (SB) and sleep for people with chronic obstructive pulmonary disease (COPD). This study aimed to: (1) identify what people with COPD from South Australia and the Netherlands, and experts from COPD- and non-COPD-specific backgrounds considered important to improve behaviours; and (2) identify areas of dissonance between these different participant groups. Methods A four-round Delphi study was conducted, analysed separately for each group. Free-text responses (Round 1) were collated into items within themes and rated for importance on a 9-point Likert scale (Rounds 2–3). Items meeting a priori criteria from each group were retained for rating by all groups in Round 4. Items and themes achieving a median Likert score of ≥7 and an interquartile range of ≤2 across all groups at Round 4 were judged important. Analysis of variance with Tukey’s post-hoc tested for statistical differences between groups for importance ratings. Results Seventy-three participants consented to participate in this study, of which 62 (85%) completed Round 4. In Round 4, 81 items (PA n = 54; SB n = 24; sleep n = 3) and 18 themes (PA n = 9; SB n = 7; sleep n = 2) were considered important across all groups concerning: (1) symptom/disease management, (2) targeting behavioural factors, and (3) less commonly, adapting the social/physical environments. There were few areas of dissonance between groups. Conclusion Our Delphi participants considered a multifactorial approach to be important to improve PA, SB and sleep. Recognising and addressing factors considered important to recipients and providers of health care may provide a basis for developing behaviour-specific interventions leading to long-term behaviour change in people with COPD
High levels of sewage contamination released from urban areas after storm events: A quantitative survey with sewage specific bacterial indicators.
BACKGROUND:Past studies have demonstrated an association between waterborne disease and heavy precipitation, and climate change is predicted to increase the frequency of these types of intense storm events in some parts of the United States. In this study, we examined the linkage between rainfall and sewage contamination of urban waterways and quantified the amount of sewage released from a major urban area under different hydrologic conditions to identify conditions that increase human risk of exposure to sewage. METHODS AND FINDINGS:Rain events and low-flow periods were intensively sampled to quantify loads of sewage based on two genetic markers for human-associated indicator bacteria (human Bacteroides and Lachnospiraceae). Samples were collected at a Lake Michigan estuary and at three river locations immediately upstream. Concentrations of indicators were analyzed using quantitative polymerase chain reaction (qPCR), and loads were calculated from streamflow data collected at each location. Human-associated indicators were found during periods of low flow, and loads increased one to two orders of magnitude during rain events from stormwater discharges contaminated with sewage. Combined sewer overflow (CSO) events increased concentrations and loads of human-associated indicators an order of magnitude greater than heavy rainfall events without CSO influence. Human-associated indicator yields (load per km2 of land per day) were related to the degree of urbanization in each watershed. Contamination in surface waters were at levels above the acceptable risk for recreational use. Further, evidence of sewage exfiltration from pipes threatens drinking water distribution systems and source water. While this study clearly demonstrates widespread sewage contamination released from urban areas, a limitation of this study is understanding human exposure and illness rates, which are dependent on multiple factors, and gaps in our knowledge of the ultimate health outcomes. CONCLUSIONS:With the prediction of more intense rain events in certain regions due to climate change, sewer overflows and contamination from failing sewer infrastructure may increase, resulting in increases in waterborne pathogen burdens in waterways. These findings quantify hazards in exposure pathways from rain events and illustrate the additional stress that climate change may have on urban water systems. This information could be used to prioritize efforts to invest in failing sewer infrastructure and create appropriate goals to address the health concerns posed by sewage contamination from urban areas
High levels of sewage contamination released from urban areas after storm events: A quantitative survey with sewage specific bacterial indicators - Fig 2
<p>(A) Streamflow (upper panel) and corresponding HB, Lachno2, ruminant, <i>E</i>. <i>coli</i>, and enterococci indicator concentrations (lower panel) measured during a combined sewer overflow in the Milwaukee estuary in Milwaukee, Wisconsin from 4/9/2015–4/13/2015 and (B) streamflow (upper panel) and corresponding HB, Lachno2, ruminant, <i>E</i>. <i>coli</i>, and enterococci indicator concentrations (lower panel) measured during two rain events in the Milwaukee estuary in Milwaukee, Wisconsin from 6/11/2015–6/13/2015 (event 8) and 6/14 /2015–6/16/15 (event 9). Vertical black dashed lines represent the beginning and ending dates and times that were defined for each event. HB, human <i>Bacteroides</i>; Lachno2, human Lachnospiraceae.</p
Scatter plot of log10-transformed <i>E</i>. <i>coli</i> culture results and the HB genetic marker.
<p>Quadrants were defined as <i>E</i>. <i>coli</i> above and below the water quality advisory limit of 235 CFU/100 mL, and the regression line value of HB at this limit. Interval confidence (dashed lines) have been calculated using a linear model with an r-squared of 0.27. HB, human <i>Bacteroides</i>.</p
Sampling site and flow monitoring station locations, drainage areas, and land use in Milwaukee, Wisconsin.
<p>Flow monitoring stations in the KK River and Milwaukee estuary were at the sampling locations. Map inset represents the entire Milwaukee estuary drainage area in relation to the state of Wisconsin. Base data comes from the National Land Cover Database (2011) Land Cover dataset [<a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1002614#pmed.1002614.ref034" target="_blank">34</a>]. The map was generated using GIS. GIS, geographic information system; KK, Kinnickinnic.</p
Mean daily fluxes, mean daily yields, and mean daily fluxes per unit urban area of HB and Lachno2 in the KK River, MN River, and MKE River for 11 rain events and four low-flow periods collected in Milwaukee, Wisconsin in 2014 and 2015.
<p>Y-axis is plotted on a log scale. HB, human <i>Bacteroides</i>; KK, Kinnickinnic; Lachno2, human Lachnospiraceae; MKE, Milwaukee; MN, Menomonee.</p
Peak instantaneous concentrations and maximum 24-hour mean concentrations of human <i>Bacteroides</i> (HB) and human Lachnospiraceae (Lachno2), total rainfall, and mean streamflow of storm events sampled in the Milwaukee estuary in Milwaukee, Wisconsin in 2014 and 2015.
<p>Peak instantaneous concentrations and maximum 24-hour mean concentrations of human <i>Bacteroides</i> (HB) and human Lachnospiraceae (Lachno2), total rainfall, and mean streamflow of storm events sampled in the Milwaukee estuary in Milwaukee, Wisconsin in 2014 and 2015.</p