A risk-based approach for developing standards for irrigation with reclaimed water.

A generalised quantitative risk assessment (QRA) is developed to assess the potential harm to human health resulting from irrigation with reclaimed water. The QRA is conducted as a backward calculation starting from a pre-defined acceptable risk level at the receptor point (defined as an annual infection risk of 10-4 for pathogens and by reference doses (RfD) for chemical hazards) and results in an estimate of the corresponding acceptable concentration levels of the given hazards in the effluent. In this way the QRA is designed to inform the level of water treatment required to achieve an acceptable risk level and help establish reclaimed water quality standards. The QRA considers the exposure of human receptors to microbial and chemical hazards in the effluent through various exposure pathways and routes depending on the specific irrigation scenario. By considering multiple pathways and routes, a number of key aspects relevant to estimating human exposure to recycled water can be accounted for, including irrigation and crop handling practices (e.g., non-edible vs edible, spray vs. drip, withholding time) and volumes consumed (directly vs indirectly). The QRA relies on a large number of inputs, many of which were found to be highly uncertain. A possibilistic approach, based on fuzzy set theory, was used to propagate the uncertain input values through the QRA model to estimate the possible range of hazard concentrations that are deemed acceptable/safe for reclaimed water irrigation. Two scenarios were considered: amenity irrigation and irrigation of ready-to-eat food crops, and calculations were carried out for six example hazards (norovirus, Cryptosporidium, cadmium, lead, PCB118 and naphthalene) and using UK-specific input values. The human health risks associated with using reclaimed water for amenity irrigation were overall deemed low, i.e. the calculated acceptable concentration levels for most of the selected hazards were generally far greater than levels typically measured in effluent from wastewater treatment plants; however the predicted acceptable concentration levels for norovirus and Cryptosporidium suggested that disinfection by UV may be required before use. It was found that stricter concentration standards were required for hazards that are more strongly bound to soil and/or are more toxic/infectious. It was also found that measures that reduce the amount of effluent directly ingested by the receptor would significantly reduce the risks (by up to 2 orders of magnitude for the two pathogens). The results for the food crop irrigation scenario showed that stricter concentration standards are required to ensure the effluent is safe to use. For pathogens, the dominant exposure route was found to be ingestion of effluent captured on the surface of the crops indicating that risks could be significantly reduced by restricting irrigation to the non-edible parts of the crop. The results also showed that the exposure to some organic compounds and heavy metals through plant uptake and attached soil particles could be high and possibly pose unacceptable risk to human health. For both scenarios, we show that the predicted acceptable concentration levels are associated with large uncertainty and discuss the implications this has for defining quality standards and how the uncertainty can be reduced.

Community-driven research on environmental sources of H. pylori infection in arctic Canada.

The role of environmental reservoirs in H. pylori transmission remains uncertain due to technical difficulties in detecting living organisms in sources outside the stomach. Residents of some Canadian Arctic communities worry that contamination of the natural environment is responsible for the high prevalence of H. pylori infection in the region. This analysis aims to estimate associations between exposure to potential environmental sources of biological contamination and prevalence of H. pylori infection in Arctic Canada. Using data from 3 community-driven H. pylori projects in the Northwest and Yukon Territories, we estimated effects of environmental exposures on H. pylori prevalence, using odds ratios (OR) and 95% confidence intervals (CI) from multilevel logistic regression models to adjust for household and community effects. Investigated exposures include: untreated drinking water; livestock; dogs; cats; mice or mouse droppings in the home; cleaning fish or game. Our analysis did not identify environmental exposures associated clearly with increased H. pylori prevalence, except any exposure to mice or mouse droppings (OR = 4.6, CI = 1.2-18), reported by 11% of participants. Our multilevel models showed H. pylori clustering within households, but environmental exposures accounted for little of this clustering; instead, much of it was accounted for by household composition (especially: having infected household members; number of children). Like the scientific literature on this topic, our results do not clearly implicate or rule out environmental reservoirs of H. pylori; thus, the topic remains a priority for future research. Meanwhile, H. pylori prevention research should seek strategies for reducing direct transmission from person to person.

What do we know about benefits of H. pylori treatment in childhood?

Policy analysis shows that H. pylori test and treat strategies targeting adults at moderate to high risk of H. pylori-induced disease is likely to be cost-effective for preventing digestive diseases responsible for a large global disease burden. Little is known, however, about health benefits to children from eliminating this infection. We conducted a systematic review of the evidence regarding health benefits to children from treatment to eliminate H. pylori infection.   We systematically searched Ovid MEDLINE for pertinent review articles published through 2012. We excluded reviews focused on treatment efficacy and scrutinized reference lists of selected reviews to identify additional eligible reviews. Fifteen reviews met specified inclusion criteria. Overall, they show that few reported studies investigating pediatric health effects of treatment for H. pylori infection were well designed with adequate statistical power. Thus, there is insufficient evidence for drawing conclusions about health benefits to children from treatment to eliminate H. pylori infection.

Oceans of opportunity or rough seas? What does the future hold for developments in European marine policy?

The management of European seas is undergoing a process of major reform. In the past, oceans and coastal policy has traditionally evolved in a fragmented and uncoordinated manner, developed by different sector-based agencies and arms of government with competing aims and objectives. Recently, the call for integrated and ecosystem-based approaches has driven the conceptualization of a new approach. At the scale of Europe through the Integrated Maritime Policy and Marine Strategy Framework Directive and in national jurisdictions such as the Marine and Coastal Access Act in the United Kingdom, ecosystem-based planning is becoming the norm. There are major challenges to this process and this paper explores, in particular, the opportunities inherent in building truly integrated approaches that cross different sectors of activity, integrate across scales, incorporate public involvement and build a sense of oceans citizenship.

Nurses' perceptions of hospice palliative care volunteers.

A total of 50 nurses (hospital and home care) responded to a survey designed to measure: (1) their attitudes toward, and knowledge of, hospice palliative care volunteers; (2) the types of tasks they felt it was appropriate for volunteers to perform; and (3) how valuable they felt different members of the hospice palliative care team are. In addition, they were asked to respond to some open-ended questions (eg, "Do you feel that it is appropriate for hospice palliative care volunteers to know patient medical information?"). The nurses' responses to the "Attitude/Knowledge" part of the survey revealed that they generally held positive attitudes toward volunteers. The majority of the nurses felt that it was appropriate for volunteers to perform most of the tasks listed, except for hands-on patient care. Nurses rated the value of nurses, family members, doctors, and pharmacists significantly higher than volunteers. Fifty-three percent of the nurses felt that volunteers should know patient medical information, and 77% thought that volunteers should have the opportunity to provide input regarding patient care. Also, 75% of the nurses felt that volunteers made their jobs easier, and 56% felt that volunteers should be included in team meetings. When asked to list the topics covered in a hospice palliative care volunteer training program, 73% of the nurses indicated that they were not sure or did not know what topics were covered, indicating a lack of knowledge regarding volunteer training.