8. BIOLOGICAL MONITORING AND THE RESULTS OF HUMAN EXPOSURE TO TOXIC SUBSTANCES FROM THE ENVIRONMENT |
8.1 Organization of monitoring activities
This subsystem comprises the monitoring of toxic substances and their metabolites
(biomarkers of internal doses), and selected biological changes (biomarkers
of biological effects) in the body fluids and tissue of population groups
(adults, children aged
Since 2005, biological monitoring has been performed in Ostrava, Prague, Liberec and Zlín.
Participating analytical laboratories were subjected to constant quality
control of results produced.
The biological exposure limits of toxic substances in human biological
materials have not generally been established for the
8.2 Monitored factors
The factors (biomarkers) monitored over the complete monitoring period
include toxic metals (cadmium, mercury, lead) and beneficial trace elements
(copper, selenium, zinc) in adult and child blood and urine, and the hair
of children. Lead levels were monitored in the teeth of
8.2.1 Toxic metals and trace elements
Cadmium has an exceptionally long biological
Neurobehavioral and developmental changes may occur in young children at
blood lead values of 100 µg/L or even less; monitoring has not detected such
levels. Blood lead levels in the adult Czech population have declined significantly
during the monitoring period. This has led to
Of the existing forms of mercury,
Copper is contained in a number of antioxidant enzymes and plays a role in hematopoiesis and lipid metabolism. The effects of copper are determined in relation to zinc and iron content in the organism. Blood copper levels correlate with data for the German population within GerES, and with other European states. A rising trend was observed prior to 1999, after which the concentrations stabilised. Higher concentrations have been detected in mature and juvenile females (Figs. 8.4a, 8.4b). Copper concentrations in urine are shown in Tab 8.1; a rising trend was observed up to 2002.
Selenium is considered to be a trace element with beneficial effects and
its antioxidant potential plays a role in protective mechanisms against oxidation
stress and resulting disorders promoted by that process (cancer, cardiovascular
and endocrine system diseases). The blood, serum or plasma selenium level
is an indicator of saturation with this element. Concentration in the range
of
Zinc is likewise an essential element contained in a number of enzymes and plays a role in immune function and antioxidant processes. Blood zinc concentrations in the adult population have stabilised, following an initial increase in 1998 (Fig. 8.6a). In children, blood concentrations have remained unchanged over the years of monitoring (Fig. 8.6b). Mature and juvenile females have lower values than mature and juvenile males. Zinc concentrations in urine are stable (Tab. 8.1).
8.2.2 Toxic substances of organic origin
Systematic monitoring was performed of PCB indicator congeners and selected
chlorinated hydrocarbons in breast milk. The results have confirmed the dominance
of congeners 138, 153 and 180 which persist in the organism for long periods.
Other PCB congener values are over 50 % below the detection limit. Results
from the overall monitoring period
DDT concentrations presented as the sum of DDT and DDE metabolites has a decreasing trend associated with gradual decline in burden, as documented since the end of the 1980s (Fig. 8.7b). Hexachlorobenzene (HCB) concentrations in breast milk have a constant and significant declining trend over the monitoring period (Fig. 8.7c).
Czech population burden from ochratoxin A is at a low level, with median
values of
8.3 Cytogenetic analysis of peripheral lymphocytes
Cytogenetic analysis of peripheral lymphocytes used for biological monitoring of population groups enables the detection of active genotoxic substances in the environment and indication of individual resistance to, and compensation of, genotoxic burden. Values of chromosomal aberrations that are significantly higher than reference values for given monitored population groups may reveal increased exposure to genotoxic substances from the environment.
Existing data shows that values for chromosomal aberrations (CH.A) in adult
population groups from four areas in the Czech Republic had a declining
trend, as monitored prior to 1999; this is particularly apparent in view
of the levels of spontaneous values of 1.77 % in the
Values of chromosomal aberrations in the child population are generally
lower than those for adults; there was a declining tendency for both child
and adult populations in the
8.4 Genotoxic effects of ambient air
Systematic monitoring of the mutagenic activity of airborne particulate
matter
8.5 Partial conclusions
The results of 10 years of biological monitoring reveal a declining trend for the majority of monitored xenobiotics and correlate with data from other European states. In particular, there is a declining trend lead in blood, a confirmed reduction of cadmium and improved saturation by selenium in the adult population. Likewise, there is a declining trend for persistent chlorinated organic substances (PCBs, DDTs, hexachlorobenzene). Burden by these substances is firmly associated with age and variable local or individual exposure in the past. Monitoring of mycotoxins suggests higher exposures in agricultural regions.
The rising trend in values of chromosomal aberrations, including mutagenicity of outdoor air, observed over the past five years indicates increased population burden by genotoxic substances and factors, and requires detailed analysis of the possible causes.
Tab. 8.1 Metal and metaloid levels in urine of adults and children
Cadmium |
Adults |
Children |
||||||||||
1996 |
1998 |
2000 |
2002 |
2003 |
1996 |
1997 |
1998 |
1999 |
2000 |
2002 |
2003 |
|
N |
361 |
367 |
359 |
366 |
363 |
426 |
388 |
357 |
362 |
368 |
349 |
270 |
Me |
0.62 |
0.58 |
0.31 |
0.40 |
0.29 |
DL |
DL |
DL |
DL |
DL |
DL |
DL |
P5 |
0.20 |
0.25 |
0.20 |
0.10 |
0.10 |
|
|
|
|
|
|
|
P25 |
0.24 |
0.25 |
0.20 |
0.18 |
0.10 |
|
|
|
|
|
|
|
P75 |
1.08 |
1.26 |
0.71 |
0.73 |
0.56 |
|
|
|
|
|
|
|
P95 |
3.82 |
2.91 |
1.55 |
1.42 |
1.34 |
|
|
|
|
|
|
|
Lead |
Adults |
Children |
||||||||||
1996 |
1998 |
2000 |
2002 |
2003 |
1996 |
1997 |
1998 |
1999 |
2000 |
2002 |
2003 |
|
N |
304 |
290 |
330 |
335 |
322 |
426 |
388 |
357 |
362 |
368 |
349 |
270 |
Me |
3.35 |
2.54 |
4.42 |
3.12 |
2.67 |
3.76 |
1.59 |
1.86 |
0.27 |
1.52 |
3.54 |
DL |
P5 |
0.72 |
1.14 |
1.53 |
1.02 |
0.77 |
0.78 |
0.16 |
0.15 |
0.10 |
0.13 |
1.98 |
|
P25 |
1.67 |
1.63 |
2.38 |
1.82 |
1.69 |
1.43 |
0.69 |
0.48 |
0.16 |
0.38 |
2.81 |
|
P75 |
6.07 |
4.23 |
10.71 |
6.16 |
5.95 |
8.44 |
3.57 |
6.39 |
1.26 |
3.50 |
4.57 |
|
P95 |
15.46 |
11.00 |
35.35 |
21.09 |
20.36 |
17.57 |
15.13 |
25.69 |
8.48 |
13.01 |
6.39 |
|
Mercury |
Adults |
Children |
||||||||||
1996 |
1998 |
2000 |
2002 |
2003 |
1996 |
1997 |
1998 |
1999 |
2000 |
2002 |
2003 |
|
N |
304 |
290 |
330 |
335 |
322 |
426 |
388 |
357 |
362 |
368 |
349 |
270 |
Me |
0.79 |
0.55 |
0.68 |
0.53 |
0.70 |
0.25 |
0.38 |
0.26 |
0.27 |
0.35 |
0.43 |
0.28 |
P5 |
0.08 |
0.09 |
0.10 |
0.05 |
0.07 |
0.06 |
0.04 |
0.04 |
0.06 |
0.07 |
0.10 |
0.08 |
P25 |
0.40 |
0.26 |
0.29 |
0.14 |
0.25 |
0.15 |
0.18 |
0.14 |
0.14 |
0.16 |
0.18 |
0.14 |
P75 |
1.55 |
1.19 |
1.44 |
1.72 |
1.81 |
0.54 |
0.85 |
0.73 |
0.74 |
0.83 |
1.24 |
0.87 |
P95 |
3.87 |
3.80 |
5.47 |
6.45 |
6.80 |
2.59 |
2.49 |
3.85 |
2.64 |
3.15 |
3.94 |
4.46 |
Copper |
Adults |
Children |
|||||||||
1998 |
2000 |
2002 |
2003 |
1996 |
1997 |
1998 |
1999 |
2000 |
2002 |
2003 |
|
N |
290 |
330 |
335 |
322 |
426 |
388 |
357 |
362 |
368 |
349 |
270 |
Me |
6.2 |
6.0 |
21.5 |
14.2 |
10.0 |
30.5 |
35.5 |
29.9 |
32.2 |
41.8 |
24.1 |
P5 |
0.3 |
2.5 |
5.7 |
6.2 |
1.3 |
3.9 |
5.8 |
13.0 |
10.7 |
5.6 |
5.6 |
P25 |
3.5 |
4.4 |
13.0 |
10.1 |
7.6 |
17.8 |
24.6 |
22.3 |
22.7 |
25.2 |
13.4 |
P75 |
16.9 |
9.0 |
30.7 |
20.6 |
36.4 |
42.1 |
50.6 |
44.2 |
43.4 |
58.8 |
38.7 |
P95 |
43.6 |
18.9 |
51.9 |
43.0 |
150.7 |
87.5 |
86.6 |
74.4 |
64.8 |
93.4 |
74.7 |
Selenium |
Adults |
Children |
|||||||||
1998 |
2000 |
2002 |
2003 |
1996 |
1997 |
1998 |
1999 |
2000 |
2002 |
2003 |
|
N |
290 |
330 |
335 |
322 |
426 |
388 |
357 |
362 |
368 |
349 |
270 |
Me |
8.20 |
8.66 |
15.32 |
10.99 |
15.42 |
12.87 |
7.15 |
16.00 |
18.34 |
17.68 |
14.01 |
P5 |
2.16 |
1.51 |
1.69 |
1.41 |
0.93 |
0.57 |
2.69 |
1.44 |
1.54 |
4.50 |
3.67 |
P25 |
3.69 |
4.49 |
8.58 |
5.87 |
1.83 |
3.47 |
4.68 |
5.55 |
7.30 |
8.80 |
10.19 |
P75 |
26.09 |
15.23 |
22.29 |
17.74 |
47.38 |
29.83 |
12.38 |
39.55 |
37.05 |
39.87 |
19.98 |
P95 |
50.18 |
30.85 |
39.37 |
32.39 |
95.00 |
70.05 |
44.12 |
110.38 |
70.51 |
126.32 |
29.20 |
Zinc |
Adults |
Children |
|||||||||
1998 |
2000 |
2002 |
2003 |
1996 |
1997 |
1998 |
1999 |
2000 |
2002 |
2003 |
|
N |
290 |
330 |
335 |
322 |
426 |
388 |
357 |
362 |
368 |
349 |
270 |
Me |
300 |
355 |
375 |
287 |
547 |
323 |
513 |
422 |
402 |
468 |
518 |
P5 |
71 |
135 |
122 |
54 |
128 |
42 |
58 |
136 |
148 |
112 |
222 |
P25 |
205 |
242 |
253 |
178 |
370 |
173 |
274 |
278 |
286 |
305 |
376 |
P75 |
451 |
477 |
532 |
431 |
860 |
524 |
805 |
582 |
535 |
667 |
713 |
P95 |
707 |
763 |
865 |
698 |
1,365 |
874 |
1,388 |
922 |
846 |
1,013 |
1,088 |
Tab. 8.2 Metal and metaloid levels in hair of children
|
Cadmium |
Lead* |
Mercury |
Copper |
Selenium |
Zinc |
N |
|
|
|
|
|
|
Me |
|
|
|
|
|
|
P5 |
0.04–0.05 |
0.49–0.73 |
0.04–0.09 |
5.0–8.0 |
0.10–0.18 |
49–75 |
P25 |
0.07–0.09 |
0.85–1.32 |
0.09–0.16 |
7.0–9.0 |
0.10–0.26 |
89–105 |
P75 |
0.19–0.34 |
1.59–2.87 |
0.20–0.37 |
12.0–20.0 |
0.20–0.52 |
144–171 |
P95 |
0.36–0.63 |
3.19–5.10 |
0.30–0.84 |
34.5–73.5 |
0.37–0.90 |
179–229 |
* significantly decreasing trend
Tab. 8.3 Lead levels in deciduous teeth
|
1998 |
1999 |
2000 |
2001 |
2002 |
2003 |
N |
179 |
204 |
171 |
142 |
177 |
60 |
Me |
0.83 |
1.31 |
1.39 |
0.95 |
0.74 |
0.63 |
P5 |
0.30 |
0.55 |
0.69 |
0.28 |
0.32 |
0.11 |
P25 |
0.56 |
0.85 |
1.00 |
0.64 |
0.56 |
0.43 |
P75 |
1.41 |
2.04 |
2.18 |
1.32 |
1.24 |
1.09 |
P95 |
2.71 |
3.37 |
4.65 |
2.51 |
2.37 |
1.63 |
Legend for Tables 8.1–8.3:
N – no. of individuals
Me – median
P5 – 5th percentile
P25 – 25th percentile
P75 – 75th percentile
P95 – 95th percentile
DL –
Limit of detection Cd – 0.3 µg/L
Pb – 7.0 µg/L
Tab. 8.4 Cytogenetic analysis – chromosomal aberrations in blood peripheral lymphocytes of adults and children
Adults |
%AB.B. |
%AB.B. |
%AB.B. |
%AB.B. |
%AB.B. |
1994 |
1996 |
1999 |
2001 |
2003 |
|
N |
626 |
330 |
366 |
392 |
382 |
AVG |
1.40 |
1.04 |
1.06 |
1.26 |
1.65 |
P25 |
0.00 |
0.00 |
0.00 |
0.00 |
1.00 |
P75 |
2.00 |
2.00 |
2.00 |
2.00 |
2.00 |
P95 |
4.00 |
3.00 |
3.00 |
3.00 |
4.00 |
Children |
%AB.B. |
%AB.B. |
%AB.B. |
%AB.B. |
%AB.B. |
1994 |
1995 |
1996 |
1999 |
2001 |
|
N |
351 |
459 |
350 |
338 |
351 |
AVG |
1.29 |
1.23 |
0.92 |
1.14 |
1.10 |
P25 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
P75 |
2.00 |
2.00 |
1.00 |
2.00 |
2.00 |
P95 |
4.00 |
4.00 |
3.00 |
3.00 |
3.00 |
Legend:
%AB.B. – share of aberrant cells
N – no. of individuals
AVG – arithmetic mean
P25 – 25th percentile
P75 – 75th percentile
P95 – 95th percentile
Fig. 8.1a | Blood cadmium level in adults – smokers |
Fig. 8.1b | Blood cadmium level in adults – non-smokers |
Fig. 8.2a | Blood lead level in adults – males |
Fig. 8.2b | Blood lead level in adults – females |
Fig. 8.2c | Blood lead level in children |
Fig. 8.2d | Distribution of blood lead levels in children, 1996 and 2001 |
Fig. 8.3a | Blood mercury level – adults |
Fig. 8.3b | Blood mercury level – children |
Fig. 8.4a | Blood copper level – adults |
Fig. 8.4b | Blood copper level – children |
Fig. 8.5a | Blood selenium level – adults |
Fig. 8.5b | Blood selenium level – children |
Fig. 8.6a | Blood zinc level – adults |
Fig. 8.6b | Blood zinc level – children |
Fig. 8.7a | Polychlorinated biphenyls in breast milk, indicator congener PCB 153 |
Fig. 8.7b | Chlorinated pesticides in breast milk, sum of DDTs |
Fig. 8.7c | Chlorinated pesticides in breast milk, hexachlorobenzene |
Fig. 8.8 | Mutagenicity of airborne particulate matter, fraction PM10, winter seasons |