The potential human health hazard of nitrates in drinking water: a media discourse analysis in a high-income country.

BACKGROUND: Recent studies linking low levels of nitrate in drinking water to colorectal cancer have raised public concerns over nitrate contamination. The aim of this study was to analyze the media discourse on the potential human health hazard of nitrates in drinking water in a high-income country with a large livestock industry: New Zealand (NZ). METHODS: Searches of media sources ("major newspapers") held by the Factiva database for the NZ setting in the five-year period 17 December 2016 to 20 December 2021. RESULTS: The largest number of media items was observed for 2017 (n = 108), the year of a NZ general election, with a notable decrease in 2020 (n = 20) that was likely due to the Covid-19 pandemic, which dominated health media. However, the percentage of these media items with a health focus steadily increased over time, from 11.1% of all articles in 2017 to 51.2% in 2021. The most commonly mentioned health hazard was colorectal cancer, followed by methemoglobinemia. The temporal pattern of media items suggests that the release of scientific studies and scholarly blogs was associated with the publication of subsequent media items. Major stakeholders involved in the discourse included representatives of local and central government, environmental and recreational interest groups, researchers, local residents, agricultural interest groups, and health organizations. Maori (Indigenous New Zealanders) values or perspectives were rarely mentioned. CONCLUSIONS: Analysis of major newspapers for a five-year period indicated that a wide range of expert comment and opinions were made available to the public and policy makers on the issue of nitrates in water. While many different stakeholder views were captured in the media discourse, there is scope for the media to better report the views of Maori on this topic. There is also a need for articles detailing the health issues to also refer to the environmental, recreational, and cultural aspects of protecting water quality to ensure that the public, policy makers, and regulators are aware of co-benefits.

Potential effect of real-world junk food and sugar-sweetened beverage taxes on population health, health system costs and greenhouse gas emissions in New Zealand: a modelling study.

Poor diet is a major risk factor for excess weight gain and obesity-related diseases, including cardiovascular diseases, type 2 diabetes mellitus, osteoarthritis and several cancers. This paper aims to assess the potential impacts of real-world food and beverage taxes on change in dietary risk factors, health gains (in quality-adjusted life years (QALYs)), health system costs and greenhouse gas (GHG) emissions as if they had all been implemented in New Zealand (NZ). Ten taxes or tax packages were modelled. A proportional multistate life table model was used to predict resultant QALYs and costs over the remaining lifespan of the NZ population alive in 2011, as well as GHG emissions. QALYs ranged from 12.5 (95% uncertainty interval (UI) 10.2 to 15.0; 3% discount rate) per 1000 population for the import tax on sugar-sweetened beverages (SSB) in Palau to 143 (95% UI 118 to 171) per 1000 population for the excise duties on saturated fat, chocolate and sweets in Denmark, while health expenditure savings ranged from 2011 NZ$245 (95% UI 188 to 310; 2020 US$185) per capita to NZ$2770 (95% UI 2140 to 3480; US$2100) per capita, respectively. The modelled taxes resulted in decreases in GHG emissions from baseline diets, ranging from -0.2% for the tax on SSB in Barbados to -2.8% for Denmark's tax package. There is strong evidence for the implementation of food and beverage tax packages in NZ or similar high-income settings.

Modelling the impacts of tobacco denicotinisation on achieving the Smokefree 2025 goal in Aotearoa New Zealand.

AIM: To provide preliminary high-level modelling estimates of the impact of denicotinisation of tobacco on changes in smoking prevalence in Aotearoa New Zealand relative to the New Zealand Government's Smokefree 2025 goal. METHODS: An Excel spreadsheet was populated with smoking and vaping prevalence data from the New Zealand Health Survey and we projected business-as-usual trends. Using various parameters from the literature (New Zealand trial data, New Zealand EASE-ITC Study results), we modelled the potential impact of denicotinisation of tobacco (with no other tobacco permitted for sale) out to 2025. In addition to the base case (considered most likely), Scenario 1 used estimates from a published expert knowledge elicitation process, and Scenario 2 considered the addition of extra mass-media campaign and Quitline support to the base case. RESULTS: With the denicotinisation intervention, adult daily smoking prevalences were estimated to decline to under 5% by 2025 for the European/Other ethnic grouping (in the base case and both scenarios) and in one scenario (Scenario 1) for Maori (2.5%). However, prevalence did not fall below 5% in the base case for Maori (7.7%) or in Scenario 2 (5.2%). In the base case, vaping was estimated to increase to 7.9% in the adult population by 2025, and up to 10.7% in one scenario (Scenario 1). CONCLUSIONS: This preliminary high-level modelling suggests that mandated denicotinisation has a plausible chance of achieving the New Zealand Government's Smokefree 2025 goal. The probability of success would increase if supplemented with interventions such as mass-media campaigns offering Quitline support (especially if predominantly designed for a Maori audience). Nevertheless, there is much uncertainty with these results and more sophisticated modelling is forthcoming.

Prescribing Smartphone Apps for Physical Activity Promotion in Primary Care: Modeling Study of Health Gain and Cost Savings.

BACKGROUND: Inadequate physical activity is a substantial cause of health loss worldwide, and this loss is attributable to diseases such as coronary heart disease, diabetes, stroke, and certain forms of cancer. OBJECTIVE: This study aims to assess the potential impact of the prescription of smartphone apps in primary care settings on physical activity levels, health gains (in quality-adjusted life years [QALYs]), and health system costs in New Zealand (NZ). METHODS: A proportional multistate lifetable model was used to estimate the change in physical activity levels and predict the resultant health gains in QALYs and health system costs over the remaining life span of the NZ population alive in 2011 at a 3% discount rate. RESULTS: The modeled intervention resulted in an estimated 430 QALYs gained (95% uncertainty interval 320-550), with net cost savings of 2011 NZ $2.2 million (2011 US $1.5 million) over the remaining life span of the 2011 NZ population. On a per capita basis, QALY gains were generally larger in women than in men and larger in Maori than in non-Maori. The health impact and cost-effectiveness of the intervention were highly sensitive to assumptions on intervention uptake and decay. For example, the scenario analysis with the largest benefits, which assumed a 5-year maintenance of additional physical activity levels, delivered 1750 QALYs and 2011 NZ $22.5 million (2011 US $15.1 million) in cost savings. CONCLUSIONS: The prescription of smartphone apps for promoting physical activity in primary care settings is likely to generate modest health gains and cost savings at the population level in this high-income country. Such gains may increase with ongoing improvements in app design and increased health worker promotion of the apps to patients.

A survey of the smokefree status of pedestrian-only spaces in 10 New Zealand local government areas.

AIM: To describe the smokefree status and signage of outdoor pedestrian-only plazas/malls/boulevards in 10 New Zealand local government (council) areas. METHODS: The 10 council areas were a convenience sample. Council websites were examined for smokefree policies, and a systematic attempt was made to identify the five largest pedestrian-only sites with permanent seating in each council area (10 sites each for two larger cities). Field visits were conducted to all selected sites during January-May 2021. RESULTS: Smokefree policies with components covering smokefree outdoor plazas/malls/boulevards were common (80%; 8/10 councils), albeit with some gaps (eg, around signage and vaping policy). A total of 60 relevant pedestrianised sites with permanent seating were identified and surveyed. Of these, 63% were officially designated smokefree. Smokefree signage was only present in 15% (9/60) of all the sites and in 24% (9/38) of the designated smokefree sites. In these designated sites, the average number of smokefree signs was only 1.4 (range: 0 to 14). Issues identified with the signs included small size, being only a small part of a larger other sign, limited use of te reo Maori wording and not covering vaping. At sites where tables were present, 12% had ash trays on the tables (none at smokefree sites). CONCLUSIONS: Smokefree plazas/malls/boulevards in this survey had multiple policy and signage deficiencies that are inconsistent with achieving the national Smokefree 2025 goal. There is scope to address these issues with an upgrade to the national smokefree law.

Should prioritising health interventions be informed by modelling studies? The case of cancer control in Aotearoa New Zealand.

In this viewpoint, we suggest that policymakers should prioritise health interventions by using evidence around health gain, impact on equity, health-system costs and cost-effectiveness. We take the example of the new cancer control agency in New Zealand, Te Aho o Te Kahu, and argue that its decision-making can now be informed by many methodologically compatible epidemiological and health economic analyses. These analyses span primary prevention of cancer (eg, tobacco control, dietary and physical activity interventions and HPV vaccination), cancer screening, cancer treatment and palliative care. The largest health gain and cost-savings from the available modelling work for New Zealand are seen in nutrition and tobacco control interventions in particular. Many of these interventions have potentially greater per capita health gain for Maori than non-Maori and are also found to be cost saving for the health sector. In summary, appropriate prioritisation of interventions can potentially both maximise health benefits as well as making best use of government funding of the health system.

Methaneseleninic acid is a substrate for truncated mammalian thioredoxin reductase: implications for the catalytic mechanism and redox signaling.

Mammalian thioredoxin reductase is a homodimeric pyridine nucleotide disulfide oxidoreductase that contains the rare amino acid selenocysteine (Sec) on a C-terminal extension. We previously have shown that a truncated version of mouse mitochondrial thioredoxin reductase missing this C-terminal tail will catalyze the reduction of a number of small molecules. Here we show that the truncated thioredoxin reductase will catalyze the reduction of methaneseleninic acid. This reduction is fast at pH 6.1 and is only 4-fold slower than that of the full-length enzyme containing Sec. This finding suggested to us that if the C-terminal Sec residue in the holoenzyme became oxidized to the seleninic acid form (Sec-SeO(2)(-)) that it would be quickly reduced back to an active state by enzymic thiols and further suggested to us that the enzyme would be very resistant to irreversible inactivation by oxidation. We tested this hypothesis by reducing the enzyme with NADPH and subjecting it to high concentrations of H(2)O(2) (up to 50 mM). The results show that the enzyme strongly resisted inactivation by 50 mM H(2)O(2). To determine the redox state of the C-terminal Sec residue, we attempted to inhibit the enzyme with dimedone. Dimedone alkylates protein sulfenic acid residues and presumably will alkylate selenenic acid (Sec-SeOH) residues as well. The enzyme was not inhibited by dimedone even when a 150-fold excess was added to the reaction mixture containing the enzyme and H(2)O(2). We also tested the ability of the truncated enzyme to resist inactivation by oxidation as well and found that it also was resistant to high concentrations of H(2)O(2). One assumption for the use of Sec in enzymes is that it is catalytically superior to the use of cysteine. We and others have previously suggested that there are reasons for the use of Sec in enzymes that are unrelated to the conversion of substrate to product. The data presented here support this assertion. The results also imply that the redox signaling function of the thioredoxin system can remain active under oxidative stress.