Letters: October 2019

A risk at all hazards

Austria’s decision to ban glyphosate outright (Chemistry World, August 2019, p17) suggests its parliament is lacking in scientific expertise, in particular as to the distinction between ‘hazard’ and ‘risk’.

Since I consider glyphosate to present a hazard, I would avoid the ‘prolonged exposure’ to it experienced by those individuals who were awareded damages after being diagnosed with cancer.

Similarly, I question the wisdom of large-scale agricultural spraying of residual crops to allow re-use of the land. But I would judge the occasional use of a few drops applied carefully to a recalcitrant weed in the garden to be of very low risk – and very convenient. Similarly, we can hardly ban the use of electricity as plainly careless handling can be fatal but it presents very little risk if used with the appropriate precautions.

John Davis FRSC
Harpenden, UK

Power ≠ energy

Loose use of the terms ‘power’ and ‘energy’ is common in the general media, but perhaps unwelcome and confusing in Chemistry World. The article ‘Hydrogen storage gets real’ states: ‘…liquifying hydrogen takes 12kWh of power per kilo of hydrogen, equivalent to 25% of the energy that hydrogen would release in a fuel cell’ (Chemistry World, September 2019, p51). A kWh is a unit of energy, the unit of power being the kW. Perhaps as the article relates to vehicles, the power unit used should be horse power (0.75kW)?

Peter Baker CChem FRSC
Great Missenden, UK

Stay away from the vent

The article ‘Bubbly beginnings for life’s first molecules’ (rsc.li/bubbly) on the recent work by Dieter Braun’s group published in Nature includes a quote from Bill Martin stating: ‘This is another piece of evidence in favour of life’s origins at hydrothermal vents, which some of us have been saying for a long time,’ and ‘…but their findings do shift the focus from UV-based chemistry at the Earth’s surface to hydrogen based chemistry in the deep subsurface’.

At no point in the Nature paper do the authors mention a location for the prebiotic studies they carried out. The term hydrothermal is mentioned, but with reference to ‘system’, ‘settings’ and ‘activity’, not hydrothermal vents. The porous volcanic rock the authors invoke (komatiites), would be expected to be found on the deep ocean floor but equally so at shallow submarine and surface locations.

Furthermore, the authors state: ‘At shallow depths bubbles are formed by gases dissolved in water,’ which would, if anything, seem to rule out deep-sea vents. Indeed, the authors specifically avoid advocating any one particular location for their model system because they are unable to do so from the data they have acquired (Braun, personal communication). I feel your readers should be made aware of these points. 

Dougal Ritson
Cambridge, UK

Careful who you ask

Rebecca Trager reports a study that confirms what has been known anecdotally for a long time – that women tend to ask fewer questions than men in conferences and other public events (Chemistry World, August 2019, p13). There have been other studies showing the same thing.^1,2

At the Cheltenham Science Festival we have been aware of this for several years. We have found that when a woman is chosen to ask the first question, there are far more likely to be additional questions from women. Our advice would be that this should be made standard practice at departmental seminars, conferences and public engagement events.

Marieke Navin
Head of Cheltenham Science Festival

Vivienne Parry
Chair of Cheltenham Science Festival

Helen Czerski, Mark Maslin, Mark Miodownik and Andrea Sella
Advisory board of Cheltenham Science Festival, UK

References

1 A J Carter, A Croft, D Lukas, G M Sandstrom, PLoS One, 2018, 14, e0212146 (DOI: 10.1371/journal.pone.0212146)

2 M Kuo, Science, 2017, DOI: 10.1126/science.caredit.a1700010

We are scientists 

I read Nessa Carson’s article (Chemistry World, September 2019, p47) with interest and empathy. I think she is applying far too narrow a definition of ‘scientist’, and one unnecessarily influenced by the intellectual snobbery (sorry) of the academic community. It does not matter in the slightest what you do for a living. If you believe that the definition of a scientist is somebody who constantly asks the question ‘How do you know?’; if you believe that evidence-based knowledge is the only knowledge worthy of respect; if you believe that a scientist is somebody who is constantly prepared to be proved wrong: then you are a scientist and you should be proud of it.

Norman Kean FRSC
Kilbrittain, Ireland

Don’t blame the flask

Mark Gilligan’s criticism that chemists are not buying expensive ‘flow’ equipment is unfair (Chemistry World, September 2019, p5). Chemists have used continuous reactors and processes in many laboratories and manufacturing sectors for over 100 years to gather data or make materials. ‘Flow’ is a new term applied to a well-established technology.

The new flow equipment for use in the laboratory does have some uses, with notable pros and cons. However, the reactor tool should be selected to meet needs based on the chemical and physical characteristics of an experiment: kinetics, phases, auxiliary reagents/solvents, hazards, as well as data required, material quantity and time. The chemist could select a reactor for batch, semi-batch, plug-flow or continuous reaction in round-bottomed flasks, straight sided flasks or tanks, loop reactors, pipes or coils, NMR-tubes, etc.

A round-bottomed flask is fine for many reactions and wholly inappropriate for others. A lack of reproducibility comes from a failure to understand and control critical parameters and from the selection of inappropriate conditions and equipment. This is as true for round-bottomed flasks as it is for flow equipment.

Substituting a round-bottomed flask for complex electronic flow equipment can be an unnecessary waste of time and resources. Flow equipment will not replace round-bottomed flasks: both have a useful role in the chemist’s tool kit along with other reactor systems.

David A Jackson
Helmshore, UK