Concentrations and isomer profiles for 24 per- and polyfluoroalkyl substances (PFASs) were monitored over 5 months (February-June, 2010) in municipal landfill leachate. These data were used to assess the role of perfluoroalkyl acid (PFAA) precursor degradation on changes in PFAA concentrations over time. The influence of total organic carbon, total suspended solids, pH, electrical conductivity (EC), leachate flow rates, and meteorological data (precipitation, air temperature) on leachate PFAS concentrations was also investigated. Perfluoropentanoate and perfluorohexanoate were typically the dominant PFASs in leachate, except for March-April, when concentrations of perfluorooctane sulfonate, perfluorooctanoate, and numerous PFAA-precursors (i.e., (N-alkyl) perfluorooctane sulfonamides and fluorotelomer carboxylic acids) increased by a factor of 2-10 (~4 μg/L to ~36 μg/L ΣPFASs). During this time, isomer profiles of PFOA became increasingly dominated by the linear isomer, likely from transformation of linear, telomer-manufactured precursors. While ΣPFAA-precursors accounted for up to 71% of ΣPFASs (molar basis) in leachate from this site, leachate from a second landfill displayed only low concentrations of precursors (<1% of ΣPFASs). Overall, degradation of PFAA-precursors and changes in leachate pH, EC, and 24-h precipitation were important factors controlling PFAS occurrence in leachate. Finally, 8.5-25 kg/yr (mean 16 kg/yr) of ΣPFASs was estimated to leave the landfill via leachate for subsequent treatment at a wastewater treatment plant.
Halving food waste by 2050 as per the Sustainable Development Goal 12.3 is key to securing a food system that is sustainable. One approach to reducing household food waste is through education campaigns. We recruited 501 households divided into three types of intervention groups and compared with a control group to better understand the efficacy of diverse education campaign approaches. Food waste interventions included a passive approach (handouts), a community engagement approach, and a gamification approach. We conducted waste audits, household surveys (pre- and post-intervention), and a focus group at the end of the campaign. The passive and gamification groups had similarly high levels of participation, while participation in the community group was very low. The passive group and the gamification group had higher self-reported awareness of food wasting after the campaign and lower food wastage than the control group. Waste audits found marginally significant differences between the game group and the control (p = 0.07) and no difference between the other campaign groups and the control group in edible food wasted. Frequent gamers were found to generate less edible food waste than infrequent gamers. We conclude that the evidence about the potential for gamification as an effective education change tool is promising and we recommend further study.
Objective
To assess the acceptability of using self-collection as a method of sampling for human papilloma virus testing in rural China.
Methods
174 women from the national cervical cancer screening programme in Xiangyuan County, China, were enrolled in our study and underwent self-collection, clinician collection, colposcopy examination and were administered questionnaire. The questionnaire assessed the patients' preference and acceptability of collection method.
Results
The mean overall acceptability score for self-collection, although significantly less than the overall score for clinician collection (p<0.01), still is well above 4 (4.33 of 5), indicating high acceptability. The acceptability scores for self-collection and clinician collection were not significantly different on scales measuring comfort and convenience (p>0.05). The scores were significantly lower for self-collection on scales measuring trust, ability to collect specimen and perceived effects of testing compared with clinician collection (p<0.01). 74% of participants preferred clinician collection, and of these participants, 86% preferred it because they thought the results were more accurate.
Conclusions
The study shows that self-collection was highly acceptable and that self-collection and clinician collection were equally comfortable and convenient; however, the participants still preferred clinician collection because of lack of trust in the results of self-collection. This indicates that self-collection is an acceptable potential method for screening but education programmes about the validity of self-collection that target general population may be needed prior to implementation.
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