www.czechglobe.cz
Physics and Health
Global Change Research Institute CASGlobal Change Research Institute CAS
February 2018
Jan Hollan,
Public Health Departement
Faculty of Medicine, Masaryk
University
film Wake up, Freak out (12 min)
● The ever increasing (and huge already)
influence on public health: climate change
● caused by global warming
● which is caused by the fact that greenouse
effect became stronger
● and that mainly due to CO2 from fossil fuels
1. Climate change
Why is our Earth warming?
The greenhouse effect became stronger...
Greenhouse effect: A process in which
the planet surface is irradiated not just by the Sun, but by the
radiation emitted by the planetary atmosphere as well
The essence of greenhouse effect is the higher transmissivity of the air for solar
radiation (of wavelengths mostly below 3 μm) than for the radiation of Earth
surface and of the air itself (mostly over 3 μm, i.e., longwave infrared).
In case of a greenhouse, the additional downward radiation is emitted by the glass
or plastics transparent to solar radiation. In case of the atmosphere, the emitting
substances are just such gases, whose molecules are composed by more than 2
atoms – the greenhouse gases.
The process can be viewed from the opposite direction as well:
radiation escaping to the space comes mostly not from the warm
surface, but from the very cold air at large heights.
(Radiation of the Sun, as well as that of the parts of the Earth – of the air, soil or sea
is caused by their temperatures. As all radiation, it is a heat transport.)
source: Veronica, designer Olga Pluháčková;
please study the fully readable czech/english pdf file
version of the poster
How strong is the downward
radiation of the atmosphere?
A square metre of the surface gets, in average, third
of a kilowatt of this (longwave) infrared radiation
Absorbed Solar radiation per metre square of Earth
surface is twice lower!
The natural greenhouse effect is very
strong indeed:
twice stronger than sunshine absorbed by
Earth surface
and so its, actually rather small, one-per-cent
increase, caused by us adding greenhouse gases
(carbon dioxide from fossil fuels mainly) to the
atmosphere,
causes a never-seen warming of the planet
More information on physics of that warming, its manmade
causes, impacts of climate change and the
mitigation of the warming see at:
http://amper.ped.muni.cz/gw/activities/
Here we limit ourselves to its health effects.
Drought
● in Czechia, just the profits in agriculture are
affected, and some discomfort for inhabitants may
happen
● in regions which were always rather dry, but still
quite productive in recent past, thanks to winter
precipitation, the decline of precipitation
together with temperature increase results in
disruption
● that's the case of Syria with a series of dry winters
2007-2010 (did not happen 1000 years before)
● disruption due to drought affected Somalia, Sudan,
Afghanistan, drought expells people from Mexican
countryside
Loss of livelihood leads to
● conflits, up to a civil war
● disassembly of state structures
● migration inside the region
● emigration of the strongest ones or those who
are subsidised by relatives in a hope that they
might be able to send back enough money in
future, so that the families remaining in their
original countries may be able to live there
decently
Another deterioration or loss of
livelihoods
● deluges nad floods (long-lasting, uncommonly strong
monsune precipitation, short and extremelly intense
ones from hurricanes-typhoones-cyclones)
● devastation by extreme wind
➢ in both cases, loss of access to potable water and
resulting morbidity and mortality (see
The Conversation, 2018-01-25)
● “merely” altered weather patterns, making food
production (common for many preceding generations)
more complicated up to impossible
● less food from sea (warming, acidification, anoxia)
● and sea level rise
Stable climate – the most important
natural source
● functioning the whole Holocene (>10 000 a)
● enabled the developement of civilisation in
various Earth regions
● but we have lost it already, due to our emissions
● further loss can – should – has to be slowed
down
● we are not doing that, just wishing:
Paris Agreement…: keep global warming well
below 2 K, as close to 1,5 K as possible
● but we have warmed the Earth by >1 K already
Any consuption,
if fed by fossil fuels
and not being indispensable,
is immoral
● This concerns almost all heating, travel, electricity
● and also production of anything (how much fossil carbon
has been cosumed for it is reflected by the product price).
● Production depends on discarding and repeated
buying of new products.
Addendum:
we did not speak about emissions of methane and
nitrous oxide. To lower them, a grand reduction of milk
products and meat is needed, implying a much larger
proportion of vegetable-based food. This would be
beneficial to health directly as well. Anybody who is not a
vegan can contribute to such transition...
From an encyclical letter Laudato si'
of Pope Francis
on Care for our Common Home
14. I urgently appeal, then, for a new dialogue
about how we are shaping the future of our
planet. We need a conversation which includes
everyone, since the environmental challenge we
are undergoing, and its human roots, concern
and affect us all. …
(see its full text on the Vatican site – if you did
not study it yet, please do it now; it is the most
thorough view of the problems of our world,
available in many languages)
51. ...There is a pressing need to calculate the use
of environmental space throughout the world for
depositing gas residues which have been
accumulating for two centuries and have created a
situation which currently affects all the countries of
the world. The warming caused by huge
consumption on the part of some rich countries
has repercussions on the poorest areas of the
world, especially Africa, where a rise in
temperature, together with drought, has proved
devastating for farming. ...
and a quote by Prince Charles:
„The efforts to lower the amount of greenhouse
gases through international agreements is
welcome, but they come, unfortunately, ten
years too late.“
and a quote by Prince Charles:
„The efforts to lower the amount of
greenhouse gases through international
agreements is welcome, but they come,
unfortunately, ten years too late.“
● the quote is from a leaflet on Greenhouse Effect
issued by the Okologie-Institut in Austria in...
1991
A concrete problem: Heat waves
● Czech etc. problem is, we are not accustomed to
them (they are dangerous for old people mainly)
● in hot, rich countries an evident rise of mortality
(see an article from 2014 on Arizona)
● in very hot and humid regions, an emergence of
situations when people die from overheating
even when avoiding any physical activity (their
basal metabolism produces more heat than
evarporative cooling can carry away)
● (basal metabolism: ~ 100 W)
● „wet bulb temperature“ - what is it? (preparation
and observation)
Up-to-date overview: The Lancet
The Lancet Countdown on health and climate
change:
from 25 years of inaction to a global
transformation for public health
➢ a 2017-10-30 article, register (or just log-in, if
you are registered already) to get the full text
2. CO2 not just as an indicator of
air purity indoors
● Metabolism: oxidation of ingested sugars, fats,
proteins
● Its main products: CO2 a H2O in exhaust air
● - both about 40 g/h
● water vapour goes away together with odours
and salt by skin too (perspiratio invisibile)
● another stuff is expelled as a part of urine
Keeling curve
CO2 concentration was
0.28 ‰ centuries ago,
now it went over 0.4 ‰.
It was always below
0.30 ‰ during
Quarternary
an animated graph of CO2 - see
www.esrl.noaa.gov/gmd/ccgg/trends/history.html
Curiously, >1 ‰ of CO2 has a health
effect in itself
● how is that possible?
● if we breath out...
how many per cent of carbon dioxide?
Curiously, >1 ‰ of CO2 has a health
effect in itself
● how is that possible?
● if we breath out 5 % of carbon dioxide?
● sometimes we hear that “the oxygen is
consumed” – but its amount in the exhaled air is
whole 16 % (from the original 21, minus 5 from
carbon oxidation), so its partial pressure is like
in 2500 m height in mountains (Alps etc.)
● (see ev. https://en.wikipedia.org/wiki/Breathing)
● on oxygen in the Earth atmospehre see a chapter 7.2, A
question to contemplate: Do we need trees to produce oxygen?
– in a book Climate and Flows of Substances (2015)
Curiously, >1 ‰ of CO2 has a health
effect in itself
● 2 experiments in the US showed that even such
a very low concentration in the inhaled air
affects cognitive performance – the experiments used
a generous ventilation with or without an added CO2. See a
paper from 2012 and (incl. different ventilation rates) from 2016
● the main issue is still that CO2 is a proxy for
odours which cause sleepiness and decline of
attention
● and a proxy for possible pathogens from
infectious persons
● relative humidity is less suitable as a proxy, as building
materials and furniture buffer its variation
3. What to do during heatwaves
● Don't go outside in the afternoon
● Take siesta as people in southern countries
● Minimalise physical activity
● (Announce heat holidays)
● Drink generously (be aware that old people
have no lust to do so – how should we help?)
● Avoid heat intrusion indoors – how?
● Cool the interior by intense ventilation late at
night and early morning
Protecting indoors against heat
● Let just that much sun in, what is needed for
illuminantion (blue sky is preferred)
● That needs movable shades at window exteriors
● Sky-lights, when high enough (so that direct sunlight
remains there together with heated air) are very good
for that
● Afternoon ventilation just through „Komfortlüftung“, a
device shifting the heat from inlet air stream to outlet
one (so-called heat recovery, better known from its
winter use)
● Just fans agitating the air instead of open windows
drauht (know the ceiling ones? And the „computer“
ones at <12 V?)
What hinders a generous nighttime
ventilation?
● Institute rules
● Draught is difficult to achieve in appartement
houses at windstill weather
● Fears that something or somebody will com
through open doors or windows (how to avoid it
without compromising ventilation?)
● Lack of being used to do that
● We have „air conditon“, so what? (what it is in
fact, what harm it does)
4. The notion of
„room temperature“
● Having a constant temperature may suite a laboratory
(together with humidity, eventually).
● Is it a reasonable target for living rooms and so on?
● Is it practical, comfortable and healthy to maintain the
same indoor temperature both during frosts and heat
waves?
● What temperatures used to be at home and in offices
100 years ago in the course of the day and year?
● What are the „temperatures in various directions“ in
common rooms during frosts?
● Temperatures of what? Of the „bulb“... affected by what?
Passive standard for buildings
● means winter interiors without significant
temperature gradients
● without cold air draughts
● and so without a need of very warm surfaces
(radiators, stoves) – let's realise that in warmer
periods, when even sub-standard buildings
have no cold windows and corners, we don't
need such heating surfaces, even if the indoor
air is cooler than it is commonly in winter
What are the thermometer readings
in the rooms used by you?
● (discussion, reports on leaflets)
● animals in our latitudes adapt seasonally to
differing temperatures
● people did so too, in the past
● the advantage of that was a larger basal
metabolism in cold periods
● (mediated by a shortening daylight length, too,
probably)
● most of us don't have this seasonal adaptation
now
~18 °C is enough
Heating homes to at least 18 °C in winter poses
minimal risk to the health of a  sedentary person,
wearing suitable clothing.
Daytime recommendations
- The 18  °C threshold is particularly important for people
over 65yrs or with preexisting medical conditions.
Having temperatures slightly above this threshold may be
beneficial for health.
- The 18  °C threshold also applies to healthy people (1 –
64)*. If they are wearing appropriate clothing and are
active, they may wish to heat their homes to slightly less
than 18  °C
Evolution of average temperatures of British
interiors
● more see
http://amper.ped.muni.cz/pasiv/standardy/kTeplotam_zimnich_interieru.pdf
and references from there.
Staying in (common long ago) cool
environments increases the amount
of Brown Adipose Tissue and so the
ability to heat oneself when
appropriate
● Not only is the life more comfortable during
winter (cold is often not perceived as
unpleasant)
➢ see Human whole body cold adaptation,
(Temperature, 2016-02-22)
● but it can be a way to counter overweight and
obesity
More on heat and cold
● see Encyclopaedia of Occupational Health and
Safety 4th Edition, http://www.ilocis.org/
(English and French)
● and its Chapter 42, Heat and Cold
● (I recommend some other chapters, like that
50 on vibrations as well – but the chapter on Light
completely neglects its harmful effects at night – the
disruption of circadian rhythm and sleep; the Encyclopedia
is partly outdated)
5. What relative humidities do we
encounter; which ones are harmful
● relative humidity: ratio of water vapour content
to that one, when the air would be saturated
● absolute humidity: grammes of vapour in one
cubic metre of air
● during frosts, the abs. humidity is very low,
during hot days it can be high
● when a very cold air comes indoors and is
heated, its relative humidity plummets
● a reliable measurement of rel. humidity: a pair
of thermometres, one of them being wet
When the high relative humidity
harms
● during heat waves (sultriness) – it is
preferable to dehumify it before letting it indoors
➢ how? cooling it low enough
➢ the humidity won't be really low, like below
65 %, but that's OK already
● in bad (that is, those not obeying the passive
standard) intensely inhabited buildings during
frosts: dampness of cold areas of walls, mainly
in corners and behind furniture; mold grow
➢ easy symptomatic (non-causal) help -
ventilation
Low winter humidity is always bad
● how it comes to existence indoors? - discussion
● an unequivocal factor promoting flu incidence,
see Flu Weather: It's Not the Cold, It's the
Humidity,
www.wunderground.com/cat6/flu-weather-its-not-cold-its-humidity
(2018-02-09)
● history of temperature and dew point from Feb 20. to 25, 2018,
Brno-Tuřany (airport); other periods see
www.wunderground.com/cat6 and its history link
Prevention of dry air indoors in
winter
● let not ventilation be the more vigorous the
stronger the frost
● that is: having the building envelope tight
enough
● in passive houses: the blower-door test (by
pressure difference of 50 Pa just 0,6 of air
volume can be exchanged with the exterior;
practice shows, that the air-tightness can be
even several times better)
● making existing building enough air-tight is not
difficult, the comfort gain is wonderful (discuss)
6. What should be considered a
pollutant?
● Pollutant – an ugly word...
● Pollution – a religious notion only, long ago
● Now (starting with Silent Spring - 1962 book) –
anything we add to the natural environment
● chemicals, radiation, heat
● need not be just stuff not existing there before,
or additions which we are aware of as harming
somebody/something
● enough, if the state of environment is changed
from the natural one
● as that is the proper one – paradigm of Eden
7. What is PM, which component of it
acts most toxically?
● PM – Particulate Matter. That is, non-gaseous
particles in the air, aerosol other than fog (other
than pure water droplets).
● An index is added, meaning what amount of the
pollutant is smaller than so many micrometres
● Legal limits and commmon measurement
concerns PM10; PM2,5 is beginning to be
monitored. Both are given as microgrammes
per cubic metre
● But PM1 a PM0,1 are more important – a
preferred way is to report numbers per cm3
.
Particles around 10 μm
● agitated dust from fields and roads
● causes respiratory problems
● sediments quickly again
● A Czech example from the CHMI:
Particles below 1 μm
● staying long time in the air
● forming also from gaseous emissions of nitrous
and sulphur oxides
● the worst ones are from noncomplete burning –
nanoparticles: carbon graphitic cores with giant
relative sufrace, to which cancerogenic toxins
like PAH (polyaromatic hydrodarbons) are
adsorbed; so-called Black Carbon
● they travel down to alveolae and from them to
the blood and inside cells
● main producer: diesel engines and solid fuels
in small devices (households)
Measures against them
● at least, get rid of diesels whose particle filters
don't work as well as they did when new
● European towns announced end of personal
diesel cars within their territories in a few years
● see also the 2012 WHO European Office study
Health Effects of Black Carbon
8. Harmful electromagnetic radiation
● ionising (from nuclides, mainly from radon – not
just gamma, beta and alpha too)
● solar (UV, but also macular degeneration of
retina due to blue component after a long-year
exposure) – how much sun is enough for Dvitamine
production?
● man-made: Light at Night
(in extenso: see the slides for the 5th grade)
Light themes
● discussion: do you have enough darkness for
sleep? How do you protect yourserves from
light if it disturbs you?
● How long do you sleep in various situations
(response on leaflets)
● Why the sleep is so important, even for
studying...
● light measurement below the table, by the wall,
by the window, outside, to the eyes
● yellow glasses influence
Light as a pollutant
● Light pollution – no heavy issue?
● Outdoors: any light added artificially
(at night) alters its natural state
● Indoors? It has no natural state, being artificial
itself. As long as we light it on purpose:
● light which could harm our health...
Darkness: a basic attribute of night
● Darkness, what's that?
● Less light than short ago
or in adjacent area.
● Common in daytime too...
● There is light outdoors in nature at night,
● but less of it below a roof or in a forest.
● No light: just totally enclosed spaces.
Day and night alteration:
the basic rhytm of our world
- sunny day, winter to summer, flat terrain:
30 thousand to 100 thousand lux
- 1/1000 lx at night
- overcast: 3x to 30x less
- day/night ratio: 3 millions to 1000 millions
- full moon night – 1/10 lx
(the ratio day/night diminishes 100x)
log (horizontal illuminance / 1 lx)
clear sky, with/out Moon
And indoors?
● Orders of magnitude less light than outdoors –
originally
● Now, tens to hundreds lux at night
● Often more than during daylight...
Brno, Kuhberg
● Clear sky: 1 to 2 centilux
instead of 1 millilux
● Overcast: decilux levels
Circadian rhythm, melatonin
● natural night and melatonin production is 11 h in
average (more in winter, less in summer)
● our electric culture shortened it to the sleeptime
● breast and prostate cancer, obesity, diabetes
Stevens, R.G. Electric power use and breast cancer: a hypothesis. Am. J.
Epidemiol. 125, 556 (1987).
Stevens, R.G. Light-at-night, circadian disruption and breast cancer:
assessment of existing evidence. International Journal of Epidemiology 38, 963
-970 (2009):
Background Breast cancer incidence is increasing globally for largely unknown
reasons. The possibility that a portion of the breast cancer burden might be
explained by the introduction and increasing use of electricity to light the night
was suggested >20 years ago.
Methods The theory is based on nocturnal light-induced disruption of circadian
rhythms, notably reduction of melatonin synthesis. It has formed the basis for a
series of predictions including that non-day shift work would increase risk, blind
women would be at lower risk, long sleep duration would lower risk and
community nighttime light level would co-distribute with breast cancer incidence
on the population level.
Results Accumulation of epidemiological evidence has accelerated in recent
years, reflected in an International Agency for Research on Cancer (IARC)
classification of shift work as a probable human carcinogen (2A). There is also a
strong rodent model in support of the light-at-night (LAN) idea.
Conclusion
If a consensus eventually emerges that LAN does increase risk, then the
mechanisms for the effect are important to elucidate for intervention and
mitigation. The basic understanding of phototransduction for the
circadian system, and of the molecular genetics of circadian rhythm
generation are both advancing rapidly, and will provide for the
development of lighting technologies at home and at work that minimize
circadian disruption, while maintaining visual efficiency and aesthetics. In
the interim, there are strategies now available to reduce the potential for
circadian disruption, which include
● extending the daily dark period,
● appreciate nocturnal awakening in the dark,
● using dim red light for nighttime necessities,
● and unless recommended by a physician, not taking melatonin
tablets.
Kloog, I., Haim, A., Stevens, R.G., Barchana, M. & Portnov, B.A.
Light at Night Co-distributes with Incident Breast but not Lung
Cancer in the Female Population of Israel.
Chronobiology International 25, 65-81 (2008).
Kloog, I., Haim, A., Stevens, R.G. & Portnov, B.A.
Global Co-Distribution of Light at Night (LAN) and Cancers of
Prostate, Colon, and Lung in Men.
Chronobiology International 26, 108-125 (2009).
Kloog, I., Portnov, B.A., Rennert, H.S. & Haim, A.
Does the Modern Urbanized Sleeping Habitat Pose a Breast Cancer
Risk?
Chronobiol Int 28, 76-80 (2011)
Basic rules for outdoor lighting
(like in Slovenia and most of
Italy)
No emissions horizontally and upwards
Using just that much light, what's necessary
for the task, no more than 1 cd/m2
or 10 lx
Ads max. 10 x more luminance than
surroudings (3 x is enough)
Yellow, faint light (lux to dekalux)
for night work
and just centilux/millilux levels
for moving during sleeptime
should become a norm
Technical measures
● replace old lights by new, fainter, better aimed
ones
● dimming,
● filtering,
● shading (help yourself to sleep well – i.e.,
employ protecive aids)
Can you spoil your eyes by faint
light?
● Did you ever hear „light up! don't damage your
vision“?
● What physiology mechanism could do that?
● All creatures, do they have their vision spoiled? Do
just the happy people supplied with electricity see
really well when old?
● Faint light does not contract eye pupils, so the
vision is to be properly in focus. People over 50
have to use various glasses, cheap ones are OK,
but more than 1 or 2 are needed
● Very faint light implies more effort for the brain only,
so we are tired and go to sleep sooner – OK!
Light: Good Servant, but
a Bad Lord!
http://amper.ped.muni.cz/light/declaration/
9. Noise toxicity
● http://www.cochlea.org/en/noise
● http://www.cochlea.eu/en/pathology/presbycusis
● (on hair cells:
http://www.cochlea.eu/en/hair-cells)
● (on noise in detail, see the slides 5. grade)
Noise then and now
● how to get back to harmless levels?
Noise - various meanings
● strong sound
● sound with no recognizable tones, no
melody
● any sound we don't want to hear
● antipode of silence
● Noise – the same root as Nausea
Noise / Sound
● Sound pollution?
● (sound: OK, good, healtny, reasonable...)
● Therefore: Noise pollution
● or, better, Acoustic pollution
More noise targeting us
● Natural phenomena
● Anthropogenic sources, preindustrial
● Its new sources in the 20-th century
● … and in the 21-st one...
Weber-Fechner law
Weber-Fechner law
● what we perceive, is the ratio of inputs
● - i. e., the increment of the
● logarithm
Quantification
● L
p
= 10 dB · log(p
2
/p
0
2
)
p
0
= 2 · 10
−5
Pa
● L
I
= 10 dB · log( I / I
0
)
I0
= 10
−12
W/m
2
● That's for 1000 Hz...
What's 1000 Hz?
● and what spectral compositon the real
sounds have,
● like speech?
Some loudness levels
● pneumatic chipper at 1 metre 115
● hand-held circular saw at 1 metre 115
● power lawn mower at 1 metre 92
● diesel truck 50 km/h at 20 metres 85
● passenger car 60 km/h at 20 metres 65
● conversation at 1 metre 55
● quiet room 40
● … and what about less?
Ten times, two times, three
times..
●
● How many decibels it amounts to?
5 dB, that is some ratio of energy
fluxes
● and further 5 dB the same ratio
● together, it is 10 dB, that is 10x more
● so, 5 dB is a square root of that, or roughly
3:1 ratio:
● 5 dB more means (just a bit more than) 3x more
Health effects
● en.wikipedia.org/wiki/Noise_health_effects
● hearing impairment – over the aging-dependent one
(high frequencies most affected, loss of speech
recognition)
● tinnitus
● hypertension
● cardiovascular
● discomfort, anger
● sleep disturbance
Sleep well?
● Darkness
and silence
are a must
Technical measures
against noise
● barriers to its propagation
● emission reduction
● protect yourself!