The Science of the Total Environment 249 Ž2000. 243]256
Deposition and disease: a moss monitoring project as
an approach to ascertaining potential connections
O. WappelhorstU , I. Kuhn,
¨ J. Oehlmann, B. Markert
International Graduate School Zittau, Markt 23, 02763 Zittau, Germany
Abstract
In the years 1995 and 1996 the atmospheric deposition of elements in the EuroRegion Neisse ŽERN. was
determined in a biomonitoring project using mosses. The mosses Pleurozium schreberi and Polytrichum formosum
were chosen as biomonitors because of their wide distribution in the area studied. The moss samples were analysed
by ICP-MS and ICP-OES for their concentrations of 37 chemical elements. The results were shown in the form of
maps. The data from the moss monitoring project served as a basis for determining those elements in the deposited
material that promote the occurrence of disease. This was done by correlating the figures for the various diseases
with the appropriate element concentrations in the mosses. Indications were found that a connection exists between
the thallium content of mosses and the occurrence of cardiovascular disease and between Ce, Fe, Ga and Ge levels
in the mosses and the incidence of diseases of the respiratory system. Q 2000 Elsevier Science B.V. All rights
reserved.
Keywords: Atmospheric pollution; Biomonitoring; Deposition; Disease; Human health; Moss; Pleurozium schreberi; Polytrichum
formosum
1. Introduction
Air pollution is known to be detrimental to
human health, but it is very difficult to prove a
connection between a specific pollutant and a
disease. Such proof can only be furnished on the
U
Corresponding author.
E-mail address: [email protected] ŽO. Wappelhorst.
basis of data on atmospheric pollution and the
incidence of disease in a particular region.
In general, expensive and delicate measuring
instruments are used to ascertain the pollutant
input in a region. Such instruments have to be
installed in a measuring network, which ties up
personnel and is costly to use and maintain. As a
result, quantitative and qualitative monitoring of
the pollutants can only be carried out at a few
selected locations by this method. Biomonitoring
0048-9697r00r$ - see front matter Q 2000 Elsevier Science B.V. All rights reserved.
PII: S 0 0 4 8 - 9 6 9 7 Ž 9 9 . 0 0 5 2 1 - 5
244
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
Fig. 1. Paths by which pollutants are taken in by human beings and moss. Unlike mosses, human beings are exposed to pollutants in
numerous places and take substances in by several routes.
is a more elegant, indirect method of determining
the pollutants and their distribution. It makes use
of the plants’ ability to accumulate pollutant subs-
tances over a considerable period of time. This
makes it possible to determine pollution of the
environment at the site of a plant, e.g. a moss, as
Fig. 2. EuroRegion Neisse, where the three states Germany, Poland and the Czech Republic meet.
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
a function of time without the risk that the results
will be distorted by short-term fluctuations
ŽMarkert et al., 1999..
Besides damaging the environment, the deposition of chemical elements in all manner of forms
and compounds may also impair human health.
To determine which elements promote the occurrence of specific diseases it is necessary to compare the incidence of the disease with the element concentrations in atmospheric deposits. A
biomonitoring project using mosses was carried
out to measure this input of elements. To make it
easier to detect the differences in pollution within
the study area, the data were presented in the
form of contour maps.
Whereas atmospheric deposition is the main
source of the substances taken up by the mosses
used as biomonitors in this survey it is only one of
several paths by which such substances can be
taken in by human beings; its share of the overall
intake depends on the individual’s personal circumstances and way of life ŽFig. 1..
The EuroRegion Neisse ŽFig. 2. was chosen as
a model for the survey. It is situated at the point
where three countries } Germany, the Czech
Republic and Poland } meet. Until the early
1990s this area was infamous for its high pollution
level. The burden on the environment has since
been reduced considerably through the closing of
numerous industrial facilities and Hagenwerder
Power Station, the fitting of modern filters at the
brown coal power stations ŽBoxberg, Turow
´ . and
the replacement of old power station units by new
ones ŽBoxberg, Schwarze Pumpe. ŽWappelhorst et
al., 1999.. A further source of emissions is the
metal-working and glass industry in the Liberec
ˇ ´ Lıpa
and Ceska
´ area.
The plants chosen as biomonitors were the
mosses Pleurozium schreberi and Polytrichum formosum. The use of epiphytic plants as passive
biomonitors is an established method of determining atmospheric deposition. In Scandinavia, mosses have been used as biomonitors for
determining pollution with heavy metals since the
late 1960s ŽRuhling
and Tyler, 1968.. Numerous
¨
projects have since been carried out with mosses;
the method has been developed systematically
ŽEllison et al., 1976; Maschke, 1981; Engelke,
245
1984; Steinnes, 1984; Ross, 1990. and also used in
large-scale European studies ŽRuhling,
1994; Her¨
pin, 1997.. It is mainly the endohydric mosses
Pleurozium schreberi and Hylocomium splendens
that have been used in these studies.
The bryophytes can be divided into two groups
} the ectohydric and endohydric types } according to the manner in which they take up and
transport water ŽBuch, 1947a,b.. Ectohydric
mosses do not have differentiated internal conductive tissue. Water is transported by capillary
forces between the stem and the leaves closely
adhering to it. Such mosses have no cuticle. Endohydric mosses such as Polytrichum formosum
have an efficient internal water transportation
system and a thin cuticle. In both types, nutrients
are taken up in the same way as water ŽBuch,
1947a; Proctor, 1984.. Both ectohydric and endohydric mosses draw their nutrients almost solely
from precipitation and not from the soil through
their root-like rhizoids, which only serve to anchor the plants to the substrate.
Moss analyses were used to determine the occurrence and distribution of the elements Ag, Al,
Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga,
Ge, K, La, Mg, Mn, Mo, Na, Nd, Ni, Pb, Pr, Rb,
Sn, Sr, Ti, Tl, Th, U, V, Y, Zn and Zr in the
EuroRegion Neisse ŽERN. ŽWappelhorst, 1999..
Little is known about the environmental concentrations and distribution of some of these elements, such as Ce, La, Nd, Y and Zr, but their
industrial significance as constituents of alloys,
semiconductors and catalysts has increased in recent years.
2. Materials and methods
2.1. Sampling
The samples were collected over a period of 4
weeks from mid August to mid September in the
years 1995 and 1996. The sampling procedure
followed that of the pan-European moss monitoring project ŽRuhling,
1994., which requires that
¨
moss samples be taken from the soil in open
areas, preferably forest clearings. The sampling
sites should be at least 300 m from the nearest
246
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
major road, townrvillage or industrial facility and
at least 100 m from smaller country roads and
individual houses. To avoid the direct influence of
water dripping from the leaf canopy, the minimum distance from the nearest tree must be 5 m.
Several sub-samples were taken in an area of
50 = 50 m at each sampling site. PE gloves were
worn to prevent contamination during sampling
and further work on the plants.
In the laboratory the dirt adhering to the samples was removed and the green and brown parts
of the plants were separated. In the case of Pleurozium schreberi the green parts are the growth of
the last 2]3 years. The age of Polytrichum formosum can be determined by the antheridium cups
through which the plant has grown; the growth of
the last 2 years was used for analysis. The unwashed samples were dried at 458C and then
homogenised in a disk vibration mill with a wolfram carbide container.
material ŽPeach Leaves SRM 1547 or Cabbage
GBW 08504. was carried out in each series as a
control for the analytical results ŽMarkert, 1996..
The equipment used for analysis was ICP-MS
ŽPerkin Elmer, ELAN 5000. and ICP-OES ŽPerkin Elmer, Optima 3000.. All standards, blanks
and samples contained 3% HNO3 and also 50
ngrml Sc, Rh and Ir as an internal standard.
2.2. Instrumental analysis
Yj s f
The samples Ž300 mg. were subjected to microwave-assisted pressure digestion with 4.0 ml of
concentrated nitric acid Žsuprapur. and 2.0 ml of
hydrogen peroxide Žsuprapur. in closed PTFE
vessels. After cooling, the samples were made up
to 50.0 ml. A digestion with certified reference
žÝ /
2.3. Mapping
Inverse Distance Weighting ŽIDW. was used as
a method for interpolating the element concentrations in terms of space. The interpolation was
carried out with the aid of the Geographic Information System ARCrINFO W using the IDW interpolation function in the grid module according
to the following formula:
Formula 1:
i
Yj s value of the grid cell
d i js Distance between the measuring
point and the relevant grid cell
1
x
di j z i
z s 1.8 ŽThe exponent may take the ¨ alues
0.5]3. A higher ¨ alue means less
influence of distant measurements..
A grid with cells 350 = 350 m in size is defined
Table 1
Classification of the diseases studied according to ICD 9
ICD 9
Description of the disease
140]208
162
172, 173
204]208
390]459
393]398, 410]429
410
411]414
401]405
430]438
460]519
480]486
466, 490, 491
490]496
493
680]709
710]739
Neoplasms
Malignant neoplasms of the trachea, bronchus and lung
Malignant melanomas of the skin and other malignant neoplasms of the skin
Leukaemia
Diseases of the circulatory system
Heart diseases
Acute myocardial infarction
Other forms of ischaemic heart disease
Essential and secondary hypertension
Diseases of the cerebrovascular system
Diseases of the respiratory system
Pneumonia
Bronchitis
Chronic obstructive lung disease
Asthma
Diseases of the skin and subcutaneous tissue
Diseases of the musculoskeletal system and connecti¨ e tissue
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
Table 2
The European Standard Population according to Waterhouse
Ž1976.
Age group
0
1 to
5 to
10 to
15 to
20 to
25 to
30 to
35 to
40 to
45 to
50 to
55 to
60 to
65 to
70 to
75 to
80 to
85 q
-5
- 10
- 15
- 20
- 25
- 30
- 35
- 40
- 45
- 50
- 55
- 60
- 65
- 70
- 75
- 80
- 85
Total
Europe
1600
6400
7000
7000
7000
7000
7000
7000
7000
7000
7000
7000
6000
5000
4000
3000
2000
1000
1000
100 000
to cover the area between the points, and the
seven closest measuring points are used for calculating the value of each cell. The value calculated
for a grid cell depends on the element concentrations at the surrounding measuring points and
also on the distance between these values and the
grid cell concerned. A detailed description of the
interpolation technique is to be found in Watson
and Philip Ž1985.. For mapping, the element concentrations were divided into five classes using
the method of Erhardt et al. Ž1996.. Initially, a
standard value is formed that incorporates a homogeneous group of low values. These values }
and the standard value thus formed } reflect the
background concentration. Three further classes
lie above these standard values, and a further
class comprises lower concentrations.
2.4. Impact on human health
Air-borne pollutants are inhaled by man and
chiefly cause chronic diseases of the upper and
lower respiratory tract. At high concentrations
247
they may also cause acute disorders. After inhalation the various components may have synergistic
effects, with the result that their overall impact is
greater than the sum of the effects of the individual substances ŽBerenbaum, 1985; Spurny, 1993..
The substances entering the lungs may be taken
up by the blood and metabolised. Air pollutants
are said to be responsible for 1]5% of all additional cases of cancer ŽDoll and Peto, 1981. and,
according to some estimates, 11]21% of all cases
of lung cancer are caused by air pollution ŽKarch
and Schneiderman, 1981.. Doll and Peto Ž1981.
and Karch and Schneiderman, 1981. investigated
the health hazard resulting from the total aerosol
of the atmosphere. They did not consider its
composition and the proportions of the individual
substances. These were first investigated by
Spurny Ž1993., who compared industrial, residential and clean-air regions in his study.
An investigation into the effects of atmospheric
pollution on individuals over large areas involves
the collection of data throughout the region. Biomonitoring is an excellent means of doing this.
Such an approach was used by Cislaghi and Nimis
Ž1997. in a study in which they compared mortality from various pulmonary diseases with a biodiversity index for lichens. High correlation coefficients were found between the index and the
number of deaths from lung cancer. However, no
direct conclusions were drawn in respect of levels
of individual elements.
The present study was to be the first attempt to
compare pollution with numerous elements }
detected by using mosses as biomonitors } with
the incidence of disease.
The numbers of patients discharged from hospitals, including deaths, in the years 1993]1997
were taken as the basic data for the frequency
with which a disease occurs. In Germany this
data, which includes the diagnosis and the
patient’s sex, age and place of residence, is passed
on from the hospitals to the Statistical Offices of
the individual states every year. The diseases are
classified according to ICD 9 ŽInternational Statistical Classification of Diseases and Related
Health Problems, ninth revision, WHO. ŽTable
1..
248
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
We were able to evaluate the data from the
districts of Bautzen, Kamenz, Lobau]Zittau,
the
¨
Upper Lusatia district of Lower Silesia ŽNOL.
and the county boroughs of Gorlitz
and Hoyer¨
swerda. The data are classified according to sex
and age Ž0 to - 5, 5 to - 10, . . . , 80 to - 85, 85
and over.. The age structure, which has a bearing
on the incidence of disease, differs from one area
to another. In order to compare the disease figures for the individual areas nevertheless, it was
necessary to standardise them. Two possible
methods of standardisation were available.
In the first method the data were converted in
accordance with the European Standard Population Žsee Tables 1 and 2. ŽWaterhouse, 1976.. The
age groups are taken into account in the standardised overall incidence of a disease with a
weighting that corresponds to their share of the
standard population. In the second method the
numbers of cases of the disease are converted to
a figure per 100 000 inhabitants divided up according to sex and age; the overall incidence of
the disease per 100 000 inhabitants is then calculated. This method has the advantage that the
data can be evaluated separately according to age
and sex. But such a breakdown can lead to very
small case numbers per group and thus, cause
major errors in the results. This does not happen
with the first method. A further advantage is a
great reduction of the individual data to be
processed.
2.5. Distribution of elements in the EuroRegion
Neisse
Figs. 3]8 are examples showing the interpolated concentrations of the elements Ce, Cr,
Nd, Sn and Tl in Polytrichum formosum and the
interpolated thallium concentrations in Pleurozium schreberi. Concentrations exceeding the standard value were found for the elements Ce, Cr
and Nd shown in the figures and also for Fe, Ge,
La, Li, Nb, Ni, Pr, Th, Ti, U, V and Zr north of
Turow
´ Power Station, along the valley of the
Neisse, across the Liberec region and as far as
the south of the ERN. The other elements investigated have different distribution patterns. The
differences in distribution patterns found between
Polytrichum formosum and Pleurozium schreberi
can be explained by the morphological and physi-
Fig. 3. Cerium concentration in mgrg dry matter in Polytrichum formosum.
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
Fig. 4. Chromium concentration in mgrg dry matter in Polytrichum formosum.
Fig. 5. Neodymium concentration in mgrg dry matter in Polytrichum formosum.
249
250
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
Fig. 6. Thallium concentration in mgrg dry matter in Polytrichum formosum.
Fig. 7. Thallium concentration in mgrg dry matter in Pleurozium schreberi.
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
251
Fig. 8. Tin concentration in mgrg dry matter in Polytrichum formosum.
ological differences between the plants ŽWappelhorst, 1999.. An influence of the soil on the
element concentrations was not detected for either of the mosses.
In the ERN, the atmospheric deposition reflected in the element concentrations in the two
moss species is similar to that found in moderately to slightly polluted regions of Europe as a
whole ŽWappelhorst et al., 1999.. Exceptions to
this are those elements whose main source of
emission is the burning of brown coal. Since brown
coal deposits exist in the ERN, this fuel is one of
the major sources of energy in the region.
2.6. Disease and atmospheric deposition
To determine possible connections between deposition and disease, the incidence of the diseases
was correlated with the element concentrations in
the mosses. The concentrations of a number of
elements in the mosses Pleurozium schreberi and,
to a lesser extent, in Polytrichum formosum differ
only slightly from one sampling site to another in
the ERN. A priori, high correlation coefficients
would result between these elements and all diseases that also show little geographic difference
in incidence. But such correlations yield extremely little information; for this reason, only
elements with a mean relative deviation of at
least 35% from the median were considered. In
the ERN, differences of this magnitude were
found for Ag, Al, Be, Bi, Ce, Cr, Cs, Fe, Ga, Ge,
La, Li, Mn, Mo, Na, Nb, Nd, Pb, Pr, Rb, Sn, Th,
Ti, Tl, U, V, Y and Zr in Polytrichum formosum
and for Be, Bi, Cs, Mn, Na and Tl in Pleurozium
schreberi.
The incidences of disease converted in accordance with the standard population ŽMethod 1.
and the numbers of cases broken down according
to age and sex ŽMethod 2. were correlated with
the element concentrations in the moss samples
from the various districts. The results are similar;
for this reason, the results of Method 2 are only
given in part.
Significant correlations Ž PF 0.1. between the
element concentrations in the mosses and the
incidence of the diseases covered by the survey
are shown in Table 3. For the sake of simplicity
252
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
Be
Bi
Cs
Mn
Na
Tl
a
20]25
25]30
30]35
35]40
40]45
45]50
50]55
55]60
60]65
65]70
70]75
75]80
80]85
) 85
y0.10
0.33
0.46
0.14
0.46
0.49
y0.22
0.38
0.54
y0.23
0.07
0.39
y0.02
y0.13
y0.10
0.63
0.75
y0.08
y0.18
y0.08
0.13
0.44
0.78
0.20
y0.14
0.44
0.61
y0.07
0.31
0.63
y0.08
0.45
0.60
y0.33
0.10
0.71
y0.01
0.01
0.11
0.29
0.66
0.19
y0.18
0.20
0.42
y0.09
0.36
0.44
y0.12
0.59
0.76
y0.36
0.05
0.81
y0.03
0.76
0.85
y0.57
y0.25
0.96
y0.12
0.69
0.84
y0.48
y0.12
0.92
y0.05
0.81
0.90
y0.60
y0.31
0.98
y0.10
0.82
0.94
y0.63
y0.36
0.99
y0.05
0.86
0.92
y0.71
y0.49
0.99
Significant correlation coefficients are printed in bold type.
Be
Bi
Cs
Mn
Na
Tl
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
Table 4
Coefficients of correlation between the incidence of essential and secondary hypertension ŽICD 401]405. and element concentrations in Pleurozium schreberi in the
years 1993]1997, broken down according to age groupsa
253
254
ICD 9
- 1]5
5]10
10]15
140]208
y0.50
0.30
162
y0.68
172, 173
0.37
204]208
y0.30 I0.80
390]459 y0.27 y0.24
0.22
393]398, y0.37 I0.73 I0.75
410]429
401]405
410
411]414
y0.68
0.73
430]438
0.88 y0.68 y0.68
460]519
0.24 y0.53
0.55
466,490, y0.05 y0.34 y0.42
491
480]486
0.23
0.05
0.27
490]496
0.46
0.48
0.87
493
0.51
0.45
0.84
680]709
0.74
0.68
0.51
710]739
0.67
0.41
0.59
a
30]35
35]40
40]45
60]65
65]70
70]75
80]85
) 85
y0.29 y0.14 I0.76
0.20
y0.20 y0.14 y0.68
0.84
0.26
0.67
0.10
0.25
y0.53
0.75 y0.26 y0.65
0.67
0.64
0.82
0.42
y0.52 y0.45
0.59
0.48
0.42
y0.13
0.81
0.04
0.46
0.55
y0.15 y0.20 y0.30 y0.07
0.32
y0.36
0.56
0.77
0.12
0.59
0.30 y0.40 y0.11 y0.51
0.30
0.02
0.36 y0.13 y0.65 y0.33
0.71
0.72
0.14
0.65
0.92
0.66
0.57 y0.06
0.45
0.89
0.05
0.09
0.07
y0.68
0.66
0.48
y0.41 y0.36
0.73
0.22
0.58 y0.19
0.83 y0.01
0.46
y0.65 y0.67 y0.34
0.82
0.78
0.86
0.81
0.64
0.74
0.71
0.36
0.79
0.52
0.72
0.49
15]20
20]25
25]30
y0.40
y0.23
0.12
0.25
0.90
0.31
y0.64
y0.41
y0.21
y0.21
0.79
0.85
0.94
0.74
0.22
0.40
0.56
0.70
0.69
0.17
0.28
0.85
0.60
0.91
0.76
0.19
0.39
0.65
0.34
0.59
0.64
0.16
0.33
0.58
0.62
0.68
0.78
0.46
0.07
0.80
0.91
0.33
0.24
0.52
0.73
0.21
0.47
0.55
0.59
0.74
0.56
0.78
0.21
0.90
0.77
0.75
0.65
0.59
0.66
45]50
50]55
0.65
0.64
0.88
0.58
0.37 y0.17
0.42
0.21
0.78
0.88
0.81
0.86
0.75
0.78
0.54
0.31
y0.58 y0.11
0.38
0.73
0.10
0.31
55]60
0.83
0.82
0.74
0.60
0.64
0.48
0.69
0.91
0.72
0.42
0.84
0.87
0.75
0.87
0.94
0.45
0.86
0.74
0.55
0.56
0.42
0.76
0.71
0.56
0.39 y0.03 y0.01
0.21 y0.09
0.60
0.08 y0.15
0.05
0.64
0.85
y0.22
0.72
0.14
0.40
0.75
y0.57
0.51
0.43
Significant coefficients are printed in bold type. For classification according to ICD 9, see Table 1.
0.66
0.81
0.76
0.68
0.90
0.75
75]80
0.70
0.90
0.93
0.45
0.66
0.70
0.70
0.92
0.87
0.66
0.76
0.73
0.61
0.88
0.80
0.66
0.60
0.36
0.53
0.63
0.52
0.73
0.93
0.63
0.27 y0.36 y0.17
0.39
0.80
0.59
0.29
0.25
0.62
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
Table 5
Coefficients of correlation between thallium concentrations in Polytrichum formosum and the incidence of diseases in ERN a
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
the remaining correlation coefficients are not included. The fact that a disease is caused or promoted by increased rates of deposition of an
element would be reflected in a positive correlation; positive correlation coefficients are therefore, printed in bold type. Negative correlations
may be interpreted as a ‘protective effect’ of an
element against the disease concerned.
Correlations between the incidence of diseases
and the mean element concentrations in the moss
samples from each district. Only significant correlation coefficients Ž PF 0.1. are shown; positive
correlation coefficients are printed in bold type.
The concentrations of the elements Ce, Fe, Ga
and Ge in Polytrichum formosum correlate significantly with the incidence of malignant neoplasms of the trachea, bronchus and lung ŽICD
162. and the incidence of diseases of the skin and
subcutaneous tissue ŽICD 680]709..
There is a significant positive correlation
between the thallium concentrations detected in
the moss Polytrichum formosum and the incidence of diseases of the circulatory system in
general ŽICD 390]459.; in particular there is a
correlation with essential and secondary hypertension ŽICD 401]405., acute myocardial infarction ŽICD 410., other forms of ischaemic heart
disease ŽICD 411]414. and chronic obstructive
lung disease ŽICD 490]496.. The Tl concentration in Pleurozium schreberi also correlates significantly with the incidence of essential and secondary hypertension ŽTable 3.. The evaluation
according to age groups ŽMethod 2. gives a very
clear indication of the connection between Tl
concentrations and the occurrence of acute myocardial infarction and hypertension in the age
groups over 40 Ž Pleurozium schreberi, Table 4.
and over 25 years of age Ž Polytrichum formosum,
Table 5.. In the older age groups there are highly
significant correlations for both men and women.
Since Tl and K have a similar ionic radius Ž150
and 151 pm, respectively., Tl has an effect on the
conduction system of the heart and the cardiac
muscle ŽMarquart and Schafer,
1997..
¨
Table 4 shows the coefficients of correlation
between essential and secondary hypertension
ŽICD 401]405. and the element concentrations in
Pleurozium schreberi.
255
Table 5 shows the results of correlating the
thallium concentration in Polytrichum formosum
with the diseases in the ERN.
Significant correlations were found between
concentrations of the elements Nd, Sn and Th in
Polytrichum formosum and the incidence of
leukaemia ŽICD 204]208.. In contrast to this, the
correlation coefficient for Tl is significantly negative. Practically nothing is known about the toxicity of Nd. The toxicity of inorganic tin compounds
is generally considered to be low, but tin organyls
are suspected of having a carcinogenic effect
ŽOehlmann and Markert, 1997.. Thorium may
have a carcinogenic effect because of its radioactivity.
Chromates are carcinogenic; they mainly cause
tumours of the nose and lungs ŽMarquart and
Schafer,
¨ 1997; Oehlmann and Markert, 1997.. The
Cr concentrations detected in Polytrichum formosum show a positive but not significant correlation
Ž r s 0.63. with the malignant neoplasms of the
trachea, bronchus and lung ŽICD 162..
Significant correlations were found between the
concentrations of such elements as Ce, Fe, Ga
and Ge in the biomonitors and diseases of the
respiratory tract. Cerium may be regarded as
non-toxic, and Fe is essential to all organisms.
Gallium is slightly toxic and has a stimulant effect
like that of Ce. Germanium is also thought to be
non-toxic, but some Ge compounds are poisonous.
These elements are found in dust deposits. Their
sources are the burning of fossil fuels and the
drifting of dust on the ground. High Fe concentrations in the mosses indicate a generally high
level of pollution with dust, which may result in
respiratory tract disease.
3. Summary and evaluation
This is the first study comparing pollution with
numerous elements, determined by moss monitoring, with the incidence of various types of
disease. For most of the elements, the region
studied was found to have a level of pollution
similar to that of many other European regions.
This means that it may be regarded as a model
case.
256
O. Wappelhorst et al. r The Science of the Total En¨ ironment 249 (2000) 243]256
Since the elements are taken in chiefly by inhalation, a connection between pollution and diseases of the respiratory tract was to be expected.
A connection was indeed found between such
diseases and levels of the elements Ce, Fe, Ga
and Ge in the mosses. Unexpectedly, a correlation was also proved to exist between thallium
concentrations and heart disease.
In the case of some other elements, such as Cr,
there seems to be a connection with certain diseases but no significant correlation was observed.
The reason may be that the element concentrations in the deposits are only one of many factors
involved in pollution. Other factors, such as indoor air contaminants or personal habits, may
overlay the effects of atmospheric deposition.
The significant correlations found between the
element concentrations in the mosses Pleurozium
schreberi and Polytrichum formosum and the incidence of a disease can only provide indications as
to the possible causes of the disease. Causality is
not taken into account when the correlation coefficients are calculated. This means that correlations can never prove that a connection exists. To
do so will be the task of further studies, for which
these results may offer initial hints.
References
Berenbaum MC. Consequences of synergy between environmental carcinogenesis. Environ Res 1985;50:310]318.
¨
Buch H. Uber
die Wasser- und Mineralstoffversorgung der
Moose. I. Soc Sci Fenn Comm Biol 1947a;9Ž16.:1]44.
¨
Buch H. Uber
die Wasser- und Mineralstoffversorgung der
Moose. II. Soc Sci Fenn Comm Biol 1947b;9Ž20.:1]61.
Cislaghi C, Nimis PL. Lichens, air pollution and lung cancer.
Nature 1997;387:463]464.
Doll R, Peto RJ. US national cancer mortality. J Natl Cancer
Inst 1981;66:1193]1308.
Ellison G, Newham J, Pinchin MJ, Thompson I. Heavy metal
content of moss in the region of Consett ŽNorth-East
England.. Environ Pollut 1976;11:167]174.
Engelke R. Schwermetallgehalte in Laubmoosen des Hamburger Stadtgebietes und Untersuchungen zur Sensibilitat
¨
bei experimenteller Belastung, Dissertation, Universitat
¨
Hamburg, 1984.
Erhardt W, Hopker
KA, Fischer I. Bewertungsverfahren¨
verfahren zur Bewertung von immissionsbedingten Stof-
fanreicherungen in standardisierten Graskulturen. UWSF¨
Z Umweltchem Okotox
1996;8Ž4.:237]240.
Herpin U. Moose als Bioindikatoren von Schwermetalleintragen
} Moglichkeiten
und Grenzen fur
¨
¨
¨ flachenhafte
¨
und zeitabhangige
Aussagen. Dissertation, Universitat
¨
¨ Osnabruck,
¨ 1997.
Karch NJ, Schneiderman MA. Explaining the urban factor in
lung cancer mortality. Report to the Natural Resources
Defence Council. Washington DC: Clement Assoc, 1981.
Maschke J. Moose als Bioindikatoren von Schwermetallimmissionen. In: Cramer J, editor. Bryophytum Bibliotheka 22.
Vaduz, 1981.
Markert B. Instrumental element and multielement analysis
of plant samples } methods and applications. Chichester:
John Wiley and Sons, 1996.
Markert B, Wappelhorst O, Weckert V et al. The use of
bioindicators for monitoring the heavy-metal status of the
environment. J Radioanal Nucl Chem 1999;240Ž2.:425]429.
Marquart H, und Schafer
SG ŽHrsg... Lehrbuch der
¨
Toxikologie. Heidelberg: Spektrum Akademischer Verlag,
1997.
Oehlmann J, Markert B. Humantoxikologie. Eine Einfuhrung
¨
¨
fur
Natur- und Ingenieurswis¨ Apotheker, Arzte,
senschaftler. Stuttgart: Wissenschaftliche Verlagsbuchhandlung mbH, 1997.
Proctor MCF. Structure and ecological adaptation. In: Dyer
AF, Duckett JG, editors. The experimental biology of bryophytes. London S: Academic Press, 1984:9]37.
Ross HB. On the use of mosses Ž Hylocomium splendens and
Pleurozium schreberi . for estimating atmospheric trace metal
deposition. Water Air Soil Pollut 1990;50:63]76.
˚ Tyler G. An ecological approach to the lead
Ruhling
A,
¨
problem. Bot Not 1968;121:321]342.
˚ Atmospheric heavy metal deposition in Europe }
Ruhling
A.
¨
estimations based on moss analysis. Nord 1994;1994:9.
Spurny KR. Atmospharisches,
anthropogenes Aerosol und
¨
seine toxischen und krebserregenden Komponenten. Wiss.
Umwelt 1993;2:139]151.
Steinnes E. Monitoring of trace element distribution by means
of mosses. Fresenius J Anal Chem 1984;317:87]97.
Waterhouse J, editor. Cancer incidence in five continents, vol.
3. Lyon: IARC, 1976.
Wappelhorst O. Charakterisierung atmospharischer
Deposi¨
tionen in der Euroregion Neiße durch ein terrestrisches
Biomonitoring. Dissertation, Internationales Hochschulinstitut Zittau, 1999.
Wappelhorst O, Winter S, Heim M, Korhammer S, Markert
B. Terrestrisches Biomonitoring in der Euroregion Neiße
} Grenzen und Moglichkeiten.
In: Oehlmann J, Markert
¨
¨
¨
B, editors. Okologie
} Okosystemare
Ansatze
¨ und Methoden. Munchen
S: Ecomed-Verlag, 1999:208]224.
¨
Watson DF, Philip GM. A refinement of inverse distance
weighted interpolation. Geo-Process 1985;2:315]327.