GEMAS – soil, geology
and health implications
Anna Ladenberger
“All substances are poisons; there is none
which is not a poison. The right dose
differentiates a poison and a remedy”
(Source: http://gnosticwarrior.com/wp-content/uploads/2013/07/paracelsus.jpg)
Paracelsus (1493-1541)
Soil composition and health implications:
Rocks and minerals → food, water, air → human body;
Soil is a direct source of nutrients,
micro-elements and macro-elements – so called mineral elements;
Geochemical mapping: detection of geochemical anomalies and
establishing natural background level, at continental and regional scale;
GEMAS results can be used to elaborate the relationship between natural
geological factors and health in humans and animals;
GEMAS results improve the understanding of the influence of ordinary
environmental factors on the geographical distribution of health problems;
GEMAS results can be used in environmental medicine, environmental
geochemistry, medical geology, etc.
Macronutrients
e.g., Ca, Fe, K, Mg, P, S
(required in large amounts in diet)
Micronutrients
e.g., B, Cu, Co, Cr, F, I, Li, Mn, Mo, Ni,
Se, V, Zn
Examples of toxic
elements:
As, Be, Cr, Cd, Hg, Pb, Tl
(Source: http://www.growthproducts.com/images/pHChart.jpg)
Sixteen trace elements are
established as being essential
for good health
• bone and membrane structure (Ca)
• water and electrolyte balance (Na, K, Cl)
• metabolic catalysis (Zn, Cu, Se, Mg, Mo)
• oxygen binding and transport (Fe)
• hormone effects (I, Cr)
PATTERNS OF INFLUENCE OF THE ELEMENTS
assimilation increase
MACRONUTRIENTS
deficit
good
no difference
(B, Cu, Co, Cr, F, I, Li, Mn, Mo, Ni, Se, V, Zn)
MICRONUTRIENTS
deficit
(Ca, Fe, K, Mg, P, S)
good
NON-ESSENTIAL
toxic
lethal
(As, Be, Cd, Pb, Sb, Sn, Ti)
tolerable
toxic
lethal
(From Siegel, 2002)
Element (bio)availability
Soil varies widely in concentrations of macro- and micro(trace) elements, even without human induced environmental
contamination and agriculture.
Soil (or sediment) horizons can have high concentrations of:
• Ions released from weathering;
• Ions introduced as fertilisers (P, K, S);
• Environmental pollutants (heavy metals, etc.).
High concentrations do not mean that the element
is ’available’!
Zinc
Zinc (Zn) is an essential micronutrient
Zinc deficiency is widespread in soil
Nearly 50% of the soil on which cereals
are grown have levels of available Zn low
enough to cause Zn deficiency
(From Reimann et al., 2014, Fig. 11.63.2, p.462)
(Alloway, 2008)
(Map of Zinc deficiency in World crops
From Alloway, 2008, Fig. 6.5, p.109)
250 mg/kg
60 mg/kg
10 mg/kg
The median in Ap soil is 45
mg/kg with a typical range
from 10 to 200 mg/kg.
(From Reimann et al., 2014, Fig. 11.63.4, p.463)
Zinc
Zinc
• essential for over 300 enzymes
• antioxidant
(From Mann et al., 2014, Fig. 13.17, p.219)
Symptoms of Zn deficiency include:
poor plant growth
loss of appetite (anorexia)
decreased immune function
(From Reimann et al., 2014, Fig. 11.63.5, p.465)
Zinc
(Source: http://farmprogress.com/story-tissue-sample-yellow-corn-9-100085 )
Once identified, zinc-deficient soil can be easily
treated with fertilisers containing zinc to provide
an adequate supply of zinc to crops!
Arsenic
toxicity: arsine gas > inorganic (As3+)
> organic (As3+) > inorganic (As5+) >
organic (As5+) > As0
(From Reimann et al., 2014, Fig. 11.9.2, p.149)
up to 60% of arsenic in soil can be
bioavailable!
keratosis, skin lesions
cancerogenic (skin,
lungs, bladder, kidney,
liver)
(From: Centeno & Finkelman, 2007, Photo 2b, p.64)
10 mg/kg
(From Reimann et al., 2014, Fig. 11.9.4, p.150)
Arsenic
(From Reimann et al., 2014,
Fig. 11.9.5, p.152)
(From Reimann et al., 2014, map on DVD)
Cornwall, UK, up to 2%
As in soil
Massif Central, high As
in soil (young volcanism,
Au, Pb-Zn deposits)
Lazio region, high
As in groundwater
(25-80 µg per l),
used for crop
irrigation
(From Reimann et al., 2014,
Fig. 11.9.5, p.153)
On the local scale
(From Ladenberger et al., 2013, p.18)
Black shale Natural source of As
(black shale is often enriched in
trace elements, such as arsenic,
cadmium; some are essential,
others are not)
Skellefte mining district High As in soil and
groundwater
Environmental and health problems?
To summarise…..
GEMAS data can be applied to soil quality assessment
GEMAS data show the geographical distribution
of potential hazard areas at the continental scale
GEMAS data highlight the potential links between soil
chemistry and health issues
GEMAS data can be used for risk characterisation
and identification of areas prone to element deficiency
Thank you
anna.ladenberger@sgu.se
Mercury
- elemental (Hg0)
- inorganic (mercurous, Hg1+ or mercuric, Hg2+)
- organic (methyl-, ethyl-, or phenylmercury)
(From Ottesen et al., 2014, Fig. 4, p.4)
Residential SGV
Allowed limit according to
Natural Protection Agency
Background
(Source: http://www.grida.no/graphicslib/detail/mercury-pollution-transport-and-cycle_595d#)
Mercury
Hg:
in food (fish);
exposure from dental amalgam fillings;
disinfectant, antibacterial, antiparasitic;
crop fungicide (methyl mercury);
vaccine preservative, nasal spray.
Health effects:
neurobehavioral disorders;
severe mental retardation;
coma;
pneumonitis, respiratory failure;
kidney failure;
acrodynia (painful extremities, apathy,
pink colour, photofobia).
(Source: http://www.counterthink.com/Seafood_Mercury_Warning.asp)
(From Ottesen et al., 2013, Fig. 8,
p.10, based on data from Wheeler
& Ummel, 2008)
(From Reimann et al.,
2014, Fig. 11.29.5,
p.267)
(From Reimann et al., 2014, Fig. 11.29.2, p.264)
(From Ottesen et al., 2013, Fig. 6, p.8)
(Source: http://whyfiles.org/201mercury/)
Selenium
mobile under oxidising alkaline conditions (pH>7.5)
binds to organic matter
immobile under reducing conditions
immobile under low pH – forms complexes with Fe oxides
dietary source of Se: mushroom, garlic, sea food, liver and kidneys, fish, flour,
whole-grain products
Essential element
(enzymes, antioxidant)
Anticancer activity
Narrow range between
dietary deficiency
(<40 µg per day)
and toxicity (>400 µg
per day)
0.6 mg/kg
0.4 mg/kg
(From Reimann et al., 2014, Fig. 11.50.4, p.389)
Selenium
Selenosis in Limerick (cattle, horses)
Se toxicity in
drinking water
(Reggio)
(From Reimann et al., 2014, Fig. 11.50.5, p.391)
(From Reimann et al., 2014, map on DVD)
High in Se: black shale, phosphatic rocks, sulphides, coal, humus rich soil in coastal
regions, volcanic ashes (tuffs), fine-grained sediments
Anthropogenic Se: burning fossil fuels, smelting, sewage sludge, manure, pesticide,
phosphate fertilisers, photocopier, anti-fungal pharmaceuticals, lubricating oils, ink
Selenium
Se deficiency:
common in Sweden, Finland, Denmark
heart disease (Keshan disease)
bone and joint disease, rheumatics
poor growth and development
weak immune respond
(Photo courtesy: Gerald F. Combs, USDA)
Se toxicity:
Se excess causes hair loss, nerve and
liver damage, caries, garlic smell of
breath, blue staining of nails;
(Photo courtesy: Gerald F. Combs, USDA)
Population can adapt to high selenium intake without
showing major clinical symptoms.