A French study shows that substantial numbers of smokers grossly underestimate their risk for lung cancer

© 2015 Peter Free

Citation

European Society for Medical Oncology, Survey shows that many live in ‘denial’ of the real risks of smoking even a small number of cigarettes a day, esmo.org (17 April 2015)

A discouraging finding

Public health numbers apply to the other guy:

Many people still dangerously underestimate the health risks associated with smoking even a few cigarettes a day, despite decades of public health campaigning, French researchers have reported at the European Lung Cancer Conference (ELCC) in Geneva, Switzerland.

[Dr. Laurent] Greillier [Hopital Nord, Marseille] and colleagues analysed data from a representative survey of 1602 French people aged between 40 and 75 years.

This ‘Edifice’ survey included 1463 people with no history of cancer, of whom 481 were former smokers and 330 were current smokers, with an average daily consumption of 14.2 cigarettes.

“[W]e thought that the risk might be minimised in smokers compared with never-smokers.”

Among the whole sample population, 34% wrongly considered that a daily consumption of up to 10 cigarettes was not associated with any risk of lung cancer . . . .

“This finding . . . . shows that relatively low cigarette consumption is considered as ‘safe’ for a lot of people.

In our study, only half of subjects answered that there is no ‘safe’ cigarette.”

Only half of current smokers considered themselves at higher risk of lung cancer than the average-risk population, and less than 40% of individuals were aware that the risk of lung cancer never disappears after smoking cessation.

“It seems that people are aware about the dangers of tobacco for health, but might consider that the risks are not for themselves, but only for other people,” Greillier said.

© 2015 European Society for Medical Oncology, Survey shows that many live in ‘denial’ of the real risks of smoking even a small number of cigarettes a day, esmo.org (17 April 2015) (extracts)

The moral? — People tend to believe what they want to

Which makes achieving rationality arguably impossible.

West African ebola virus disease outbreak is finally dying down — but with Guinea still smoldering

© 2015 Peter Free

Citation

World Health Organization, Ebola Situation Report – 15 April 2015, World Health Organization – Ebola (April 2015)

Given the mortality that occurred last year, the current numbers look good

But — if one thinks back to before this massive outbreak and our acclimatization to it, even the current numbers would be worrisome:

A total of 37 confirmed cases of Ebola virus disease (EVD) was reported in the week to 12 April, compared with 30 the previous week.

Case incidence in Guinea increased to 28, compared with 21 confirmed cases the previous week.

Sierra Leone reported 9 confirmed cases, the same total as in the previous week. Liberia reported no confirmed cases.

There have been a total of 25 791 reported confirmed, probable, and suspected cases of EVD in Guinea, Liberia and Sierra Leone . . . with [10 689] reported deaths (outcomes for many cases are unknown).

© 2015 World Health Organization, Ebola Situation Report – 15 April 2015, World Health Organization – Ebola (April 2015) (extracts)

The moral? — Ebola has completely dropped out of the American press, but it is still killing people

As usual — unacknowledged, courageous and skillful people on the ground are making the critical difference.

Is there too much agricultural insecticide in our planet’s mostly unmonitored agricultural surface waters? — A meta-analysis suggests so

© 2015 Peter Free

Citation — to study

Sebastian Stehle and Ralf Schulz, Agricultural insecticides threaten surface waters at the global scale, Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1500232112 (online before print, 13 April 2015)

Citation — to press release

Universität Koblenz-Landau, Insecticide contamination of global surface waters substantially higher than expected, AlphaGalileo (14 April 2015)

Scattering poison without paying attention

The problem appears to be four-fold — according to this meta-analysis:

The few agriculture-related water and sediment pesticide levels that have been measured are too frequently high.

More than 90 percent most of the planet’s agriculture-related waters and sediments are not monitored at all.

Aquatic life forms are reportedly sensitive to pesticide concentrations that are supposedly safe in drinking water — meaning that we are imposing the wrong regulatory standards with respect to ecology as a whole.

And regulators have ignored what might be happening to life forms, when multiple insecticides — present in water at relatively lesser levels — have synergistically toxic effects on aquatic life.

From the informative press release:

A study performed at the Institute for Environmental Science of the University of Koblenz-Landau evaluated for the first time comprehensive global insecticide contamination data for agricultural surface waters . . . .

[M]ore than 40% of the water-phase samples with a detection of an insecticide concentration, exceeded respective [regulatory threshold levels].

Concerning the exposure of sediments (i.e., deposits at the bottom of the surface water bodies), more than 80% of the insecticide concentrations exceeded RTLs [regulatory threshold levels]  . . . .

The meta-analysis performed by the researchers from the University Koblenz-Landau considered 28 insecticide compounds, of which the majority is currently authorised in the EU or the US, respectively, and it comprised in total 11,300 insecticide concentrations detected in more than 2,500 surface water sites located in 73 countries and that were reported between 1962 and 2012 in 838 peer-reviewed, scientific studies.

Overall, 8,166 insecticide concentrations were detected in the water-phase and 3,134 in sediments of global water bodies.

However, out of all 11,300 insecticide concentrations, more than 52% (5,915 cases, more than 68.5% of the surface water sites analysed) exceeded the RTL, in parts up to a factor of 10,000 and beyond.

[T]he actual situation in the field potentially is even worse:

First, insecticide contamination data could be retrieved for only about 10% of global agricultural surface waters, which indicates that there is no scientific knowledge on the insecticide contamination of surface waters in large parts of the world, especially concerning Russia or large parts of South America.

Moreover, insecticide concentrations in surface waters are very hard to detect as they occur even in highly contaminated surface waters only very briefly, i.e. only during a few days per year.

However, due to the high toxicity of insecticides for aquatic organisms, these short-term peak concentrations, which occur repeatedly each year in agricultural surface waters, lead to substantial and long-lasting adverse effects on aquatic communities.

[I]n more than 80% of the samples that were analysed for various pesticide compounds, more than one, in some cases even up to 30 further pesticides were detected.

Although the resulting adverse effects of these pesticide mixtures potentially are substantially higher compared to those of single compounds, they are, however, not considered in the regulatory risk assessment procedures.

In general, aquatic organisms are highly susceptible already to insecticide surface water concentrations far below benchmark levels defined, for example, those for drinking water.

However, as stated above, legally binding environmental quality criteria are available for only very few insecticide compounds.

© 2015 Universität Koblenz-Landau, Insecticide contamination of global surface waters substantially higher than expected, AlphaGalileo (14 April 2015) (extracts, underlines added)

The moral? — Don’t hold your breath waiting for humanity to respond inquisitively and appropriately

The destruction of the commons is not something that we humans are good at dealing with.

Supernovae Ia stars appear not to be equally colored or equally luminous — which means that Universe’s expansion velocity and dark energy may have been miscalculated

© 2015 Peter Free

Citation — to study

Peter A. Milne, Ryan J. Foley, Peter J. Brown, and Gautham Narayan, The Changing Fractions of Type Ia Supernova NUV-Optical Subclasses with Redshift, The Astrophysical Journal 803(1): 20, DOI:10.1088/0004-637X/803/1/20 (10 April 2015)

Citation — to press release

Daniel Stolte, Accelerating Universe? Not So Fast, University of Arizona (10 April 2015)

Talk about a possibly mistaken critical assumption

From the press release:

The team, led by UA astronomer Peter A. Milne, discovered that type Ia supernovae, which have been considered so uniform that cosmologists have used them as cosmic “beacons” to plumb the depths of the universe, actually fall into different populations.

The findings are analogous to sampling a selection of 100-watt light bulbs at the hardware store and discovering that they vary in brightness.

[T]he findings hint at the possibility that the acceleration of the expansion of the universe might not be quite as fast as textbooks say.

“Since nobody realized that before, all these supernovae were thrown in the same barrel. But if you were to look at 10 of them nearby, those 10 are going to be redder on average than a sample of 10 faraway supernovae.”

“We’re proposing that our data suggest there might be less dark energy than textbook knowledge, but we can’t put a number on it,” Milne said.

“Until our paper, the two populations of supernovae were treated as the same population. To get that final answer, you need to do all that work again, separately for the red and for the blue population.”

© 2015 Daniel Stolte, Accelerating Universe? Not So Fast, University of Arizona (10 April 2015) (extracts)

More specifically

From the abstract:

Ultraviolet (UV) and optical photometry of Type Ia supernovae (SNe Ia) at low redshift have revealed the existence of two distinct color groups, composed of NUV-red and NUV-blue events.

We show that the ejecta velocity of NUV-red supernovae (SNe) is larger than that of NUV-blue objects by roughly 12% on average.

This velocity difference can explain some of the UV/optical color difference, but differences in the strengths of spectral features seen in mean spectra require additional explanation.

Because of the slightly different  colors for these groups, NUV-red SNe will have their extinction underestimated using common techniques. This, in turn, leads to underestimation of the optical luminosity of the NUV-blue SNe Ia, in particular, for the high-redshift cosmological sample.

Not accounting for this effect should thus produce a distance bias that increases with redshift and could significantly bias measurements of cosmological parameters.

© 2015 Peter A. Milne, Ryan J. Foley, Peter J. Brown, and Gautham Narayan, The Changing Fractions of Type Ia Supernova NUV-Optical Subclasses with Redshift, The Astrophysical Journal 803(1): 20, DOI:10.1088/0004-637X/803/1/20 (10 April 2015) (at Abstract) (paragraph split)

The moral? — Always be aware that our  supposedly consistent markers may not be

From a statistical standpoint, given the Universe’s complexity and our tenuous abilities to penetrate it — especially across great distances of space and time — I have long been skeptical that Ias were all alike.  The team’s finding does not surprise me.

Increased atmospheric nitrogen deposition — as from fuel and biomass burning, as well as fertilizer and manure emissions — appears to correlate with lower ecologic plant diversity in Switzerland — a superbly communicated study and press release

© 2015 Peter Free

Citation — to study

Tobias Roth, Lukas Kohli, Beat Rihm, Valentin Amrhein, and Beat Achermann, Nitrogen deposition and multi-dimensional plant diversity at the landscape scale, Royal Society Open Science 2: 150017, DOI: 10.1098/rsos.150017 (April 2015)

Citation — to press release

Universität Basel, Nitrogen Deposition Reduces Swiss Plant Diversity, www.unibas.ch (08 April 2015)

Methods and findings

From the study:

Nitrogen (N) is an essential plant nutrient, and many species-rich ecosystems are adapted to conditions of low N availability. Increasing N availability in such ecosystems often favours a small number of highly competitive species, resulting in decreasing overall plant diversity through competitive exclusion.

Atmospheric N deposition leading to an increased N availability is therefore an important element of global change threatening biodiversity.

Main sources of human atmospheric N emissions are combustion of fuel and of biomass and emissions from fertilizer and manure.

Here, we used data on 381 randomly selected 1 km2 plots covering most habitat types of Central Europe and an elevational range of 2900 m.

We found that high atmospheric N deposition was associated with low values of six measures of plant diversity.

The weakest negative relation to N deposition was found in the traditionally measured total species richness.

The strongest relation to N deposition was in phylogenetic diversity, with an estimated loss of 19% due to atmospheric N deposition as compared with a homogeneously distributed historic N deposition without human influence, or of 11% as compared with a spatially varying N deposition for the year 1880, during industrialization in Europe.

Because phylogenetic plant diversity is often related to ecosystem functioning, we suggest that atmospheric N deposition threatens functioning of ecosystems at the landscape scale.

© 2015 Tobias Roth, Lukas Kohli, Beat Rihm, Valentin Amrhein, and Beat Achermann, Nitrogen deposition and multi-dimensional plant diversity at the landscape scale, Royal Society Open Science 2: 150017, DOI: 10.1098/rsos.150017 (April 2015) (at Abstract and first paragraph under Introduction) (extracts)

Brilliant lay science writing

I often think that German speakers do a better job of precise English writing than Americans do.

Consider the following from the Universität Basel’s press release. It clarifies what is ambiguous in the study’s abstract — underlines added:

The weakest relation was found in the traditionally measured species richness, which measures the number of plant species per plot.

The biologists found the strongest effect in the so-called phylogenetic diversity, a measure that compares DNA sequences. High nitrogen deposition thus leads to plant species being more strongly related to each other.

The study estimates the loss in phylogenetic plant diversity due to current human-induced nitrogen deposition at 19 percent.

As a reference value, the researchers used an estimated historic nitrogen deposition without human influence.

Compared to the historic reference value, the loss in traditionally measured plant species richness was 5 percent.

The researchers also compared the data to nitrogen deposition measures from 1880, during the industrialization in Europe. The loss in phylogenetic plant diversity in this case was still 11 percent.

Tobias Roth, Lukas Kohli, Beat Rihm, Valentin Amrhein, and Beat Achermann, Nitrogen deposition and multi-dimensional plant diversity at the landscape scale, Royal Society Open Science 2: 150017, DOI: 10.1098/rsos.150017 (April 2015) (paragraphs split, underlines added)

Thus, compared to the time when humans weren’t “screwing” things up, vegetative phylogenetic diversity was 19 percent higher in Switzerland (and presumably other similarly constructed places).

More on the team’s impressive methodology

Quoted at length, due to the team’s remarkable thoroughness and its obvious intent to communicate clearly and precisely:

Fieldwork took place between 2005 and 2009 in Switzerland.

About 70% of Switzerland is mountainous, including the Alps (about 60% of Switzerland) and the Jura Mountains (about 10% of Switzerland).

Plant data are from the Swiss biodiversity monitoring indicator ‘species richness in landscapes’ (Z7), which aims to monitor vascular plant diversity at the landscape scale. Based on the national coordinate system of 41 285 1 km2 cells, a sample grid of 428 regularly spaced study plots, each of 1 km2 size, was selected using a randomly chosen starting cell.

Excluding study plots of 100% water surface, as well as study plots that were too dangerous for fieldwork because of their ruggedness, plant data from 381 study plots were used for the current study.

Qualified botanists who received special training to reduce among-observer variation performed the surveys.

For each study plot, occurrences of vascular plants were surveyed along a 2.5 km transect that followed existing trails preferably near the diagonal of the study plots. If no trails existed, surveyors marked the transect route in the field and plotted it on a map.

Transects were inspected once in spring and again in summer, assuring that data collection spanned a large variation in flowering phenologies. On 19 sample plots with short vegetation period at high elevations, only one inspection per field season was conducted.

During each inspection, surveyors recorded all plant species (presence/absence) within 2.5 m to each side of the transects both on the way forth and back, respectively.

The overall detection error was relatively small with an average of 6.6% undetected presences per species as inferred in an earlier study using site-occupancy models. Overall, the plant surveys yielded 93 621 observations of 1768 plant species.

We calculated six measures of plant diversity for each study plot: (i) total species richness (Total SR), (ii) number of species typically found on nutrient-poor soils . . .  and (iii) number of target species for which Swiss agriculture has particular responsibility of conservation. . . .

We examined (iv) community uniqueness of a study plot by calculating the average Simpson dissimilarity index of species composition for the study plot paired with each other plot. A value close to one would indicate a plot with a high proportion of unique species (i.e. a high proportion of relatively rare species); a value close to zero would indicate a high proportion of common species.

Such a measure for community uniqueness is based on the concept of ‘differentiation diversity’ and can be interpreted as differences in species composition between plots while controlling for differences in species richness.

To calculate (v) functional diversity (FD), we selected traits from the LEDA database or Flora Indicativa that are important for competition and persistence: adult longevity, plant height, presence of reserve or storage organs, root depth, seed longevity and seed mass.

As a measure for the functional distances between the species present in a community, we used Gower distances that can be used with both continuous and binary data. Our measure of FD was the sum of functional distances between each pair of species at a study plot.

Finally, we calculated (vi) phylogenetic diversity (PD) as the sum of the branch lengths for the species present in a community. The branch lengths were obtained from the molecular phylogeny of Durka & Michalski that represents 4685 vascular plant species from Central Europe.

© 2015 Tobias Roth, Lukas Kohli, Beat Rihm, Valentin Amrhein, and Beat Achermann, Nitrogen deposition and multi-dimensional plant diversity at the landscape scale, Royal Society Open Science 2: 150017, DOI: 10.1098/rsos.150017 (April 2015) (at first three paragraphs under Materials and Methods — Plant Data) (paragraphs split)

Caveat

Obviously, the team’s estimate of the pre-industrial, atmospheric nitrogen deposition rate could be in error. Which would probably deemphasize the reduction in phylogenetic diversity that we reportedly see today.

The moral? — Further corroboration for the wide swath of the human footprint

This is the kind of pains-taking study that exemplifies conscientiously done science.