Spending time in natural environments can benefit health and well-being, but exposure-response relationships are under-researched. We examined associations between recreational nature contact in the last seven days and self-reported health and well-being. Participants (n = 19,806) were drawn from the Monitor of Engagement with the Natural Environment Survey (2014/15–2015/16); weighted to be nationally representative. Weekly contact was categorised using 60 min blocks. Analyses controlled for residential greenspace and other neighbourhood and individual factors. Compared to no nature contact last week, the likelihood of reporting good health or high well-being became significantly greater with contact ≥120 mins (e.g. 120–179 mins: ORs [95%CIs]: Health = 1.59 [1.31–1.92]; Well-being = 1.23 [1.08–1.40]). Positive associations peaked between 200–300 mins per week with no further gain. The pattern was consistent across key groups including older adults and those with long-term health issues. It did not matter how 120 mins of contact a week was achieved (e.g. one long vs. several shorter visits/week). Prospective longitudinal and intervention studies are a critical next step in developing possible weekly nature exposure guidelines comparable to those for physical activity.

Introduction Proximity and access to water have long been central to human culture and accordingly deliver countless societal benefits. Over 200 million people live on Europe's coastline, and aquatic environments are the top recreational destination in the region. In terms of public health, interactions with ‘blue space’ (eg, coasts, rivers, lakes) are often considered solely in terms of risk (eg, drowning, microbial pollution). Exposure to blue space can, however, promote health and well-being and prevent disease, although underlying mechanisms are poorly understood. Aims and methods The BlueHealth project aims to understand the relationships between exposure to blue space and health and well-being, to map and quantify the public health impacts of changes to both natural blue spaces and associated urban infrastructure in Europe, and to provide evidence-based information to policymakers on how to maximise health benefits associated with interventions in and around aquatic environments. To achieve these aims, an evidence base will be created through systematic reviews, analyses of secondary data sets and analyses of new data collected through a bespoke international survey and a wide range of community-level interventions. We will also explore how to deliver the benefits associated with blue spaces to those without direct access through the use of virtual reality. Scenarios will be developed that allow the evaluation of health impacts in plausible future societal contexts and changing environments. BlueHealth will develop key inputs into policymaking and land/water-use planning towards more salutogenic and sustainable uses of blue space, particularly in urban areas. Ethics and dissemination Throughout the BlueHealth project, ethics review and approval are obtained for all relevant aspects of the study by the local ethics committees prior to any work being initiated and an ethics expert has been appointed to the project advisory board. So far, ethical approval has been obtained for the BlueHealth International Survey and for community-level interventions taking place in Spain, Italy and the UK. Engagement of stakeholders, including the public, involves citizens in many aspects of the project. Results of all individual studies within the BlueHealth project will be published with open access. After full anonymisation and application of any measures necessary to prevent disclosure, data generated in the project will be deposited into open data repositories of the partner institutions, in line with a formal data management plan. Other knowledge and tools developed in the project will be made available via the project website (www.bluehealth2020.eu). Project results will ultimately provide key inputs to planning and policy relating to blue space, further stimulating the integration of environmental and health considerations into decision-making, such that blue infrastructure is developed across Europe with both public health and the environment in mind.

Various epidemiological studies have suggested associations between environmental exposures and pregnancy outcomes. Some studies have tempted to combine information from various epidemiological studies using meta-analysis. We aimed to describe the methodologies used in these recent meta-analyses of environmental exposures and pregnancy outcomes. Furthermore, we aimed to report their main findings.

Exposure to total trihalomethanes in drinking water has been associated with several adverse birth outcomes relating to fetal growth and prematurity. We carried out a systematic review and meta-analysis of epidemiologic studies featuring original peer-reviewed data on the association of total trihalomethane exposure and health outcomes related to fetal growth and prematurity. A comprehensive literature search yielded 37 studies, 15 of which were selected for the extraction of relative risks relating adverse birth outcomes to trihalomethane exposure. Sufficient data were available for meta-analyses to be carried out for 4 adverse birth outcomes: low birth weight (LBW), term low birth weight (term LBW), preterm delivery, and small for gestational age (SGA) (including intra uterine growth retardation). We found little or no evidence for associations between third trimester trihalomethane exposure and LBW (odds ratio per 10 microg total trihalomethane/L = 1.00 [95% confidence interval = 0.97-1.03]), term LBW (1.03 [0.93-1.15]), or preterm delivery (0.99 [0.98-1.00]), but some evidence for SGA (1.01 [1.00-1.02]). There was little or no evidence for associations between total trihalomethane concentration and adverse birth outcomes relating to fetal growth and prematurity, with the possible exception of SGA. We discuss these findings and the uncertainties-relating particularly to exposure-that may have affected them.

ObjectivesThe aim of this study was to review epidemiologic evidence, provide summary risk estimates of the association between exposure to chlorination disinfection by-products (DBPs) and congenital anomalies, and provide recommendations for future studies.Data sources and extractionWe included all published epidemiologic studies that evaluated a relationship between an index of DBP exposure (treatment, water source, DBP measurements, and both DBP measurements and personal characteristics) and risk of congenital anomalies. When three or more studies examined the same exposure index and congenital anomaly, we conducted a meta-analysis to obtain a summary risk estimate comparing the highest exposure group with the lowest exposure group. When five or more studies examined total trihalomethane (TTHM) exposure and a specific congenital anomaly, we conducted a meta-analysis to obtain exposure–response risk estimates per 10 μg/L TTHM.Data synthesisFor all congenital anomalies combined, the meta-analysis gave a ...

[acf field=ehp_author_refs] [toggle title=Author Affiliations float=left width=100% margin=0 20px 20px 0 status=closed] [acf field=ehp_author_affiliations] [/toggle] [acf field=ehp_pdf] [tabgroup] [tab title=Abstract] [acf field=ehp_abstract] [/tab] [tab title=About This Article] [acf field=ehp_about_article] [text-blocks id=62755 plain=1] [/tab] [tab title=Supplemental Material] [...