Gateway effects and electronic cigarettes: a response to J-F Etter

This is a response to an essay by J-F Etter published in Addiction in 2017 (see reference #1 in the article). It was sent to Addiction which offered a 500 word letter. The full response is posted her

The Gateway Effect of E-cigarettes: Reflections on Main Criticisms

The recent spread of e-cigarette use has spurred not only enthusiasm about their harm reduction and smoking cessation potential but also concerns about possible risks from long-term use, and stalled cessation through dual use.1 Another main concern is that e-cigarette use is increasing among tobacco-naive youth2 than among only adult smokers who are using them for cessation and expectation of risk reduction.1 With youth smoking at all-time lows in several nations with advanced tobacco control programs,3–5 there are therefore concerns that e-cigarettes may stall or reverse these declines as youth who were likely to never use any form of nicotine become familiar with it, and start experimenting with other forms of nicotine delivery. These concerns were strengthened by the recent publication of a meta-analysis of longitudinal studies showing that e-cigarettes can serve as a gateway to later cigarette smoking among nicotine-naive youth.6 They were also emphasized by the 2018 report of the National Academies of Sciences, Engineering, and Medicine (NASEM),7 which concluded that such studies “provided “strong evidence of plausibility and specificity of a possible causal effect of e-cigarette use on smoking…” with the Committee “consider[ing] the overall body of evidence of a causal effect of e-cigarette use on risk of transition from never to ever smoking to be substantial” (pp. 16–32). By contrast, Public Health England concluded, “Despite some experimentation with these devices among never smokers, e-cigarettes are attracting very few young people who have never smoked into regular use”.8 Given the importance of putative gateway or “catalyst”9 effects in assessing the population impact of e-cigarettes, proponents of e-cigarettes were quick to criticize such evidence and their underlying gateway hypothesis.10–13 In the context of this debate, the gateway hypothesis is adapted to denote the use of less harmful forms of nicotine delivery (eg, e-cigarettes), leading to the use of more harmful ones (eg, combustible cigarettes).7,10–13 We here present and respond to three major criticisms that have been made of e-cigarettes’ gateway potential based on currently available evidence

Nitrogen deposition effects on ecosystem services and interactions with other pollutants and climate change

Ecosystem services are defined as the ecological and socio-economic value of goods and services provided by natural and semi-natural ecosystems. Ecosystem services are being impacted by many human induced stresses, one of them being nitrogen (N) deposition and its interactions with other pollutants and climate change. It is concluded that N directly or indirectly affects a wide range of provisioning, regulating, supporting and cultural ecosystem services, many of which are interrelated. When considering the effects of N on ecosystem services, it is important to distinguish between different types of ecosystems/species and the protection against N impacts should include other aspects related to N, in addition to biodiversity. The Working Group considered the following priorities of ecosystem services in relation to N: biodiversity; air quality/atmosphere; ecosystem changes; NO3 leaching; climate regulation and cultural issues. These are the services for which the best evidence is available in the literature. There is a conflicting interest between greenhouse gas ecosystem services and biodiversity protection; up to some point of increasing N inputs, net greenhouse gas uptake is improved, while biodiversity is already adversely affected