HEALTH RISK OF BREAST-FED CHILDREN

EXPOSED TO SELECTED POLYHALOGENATED HYDROCARBONS IN THE CZECH REPUBLIC

V.BENCKO1, M.ČERNÁ2, L.JECH3

1CHARLES UNIVERSITY OF PRAGUE, FIRST FACULTY OF MEDICINE,

INSTITUTE OF HYGIENE AND EPIDEMIOLOGY, CZECH REPUBLIC 

2NATIONAL INSTITUTE OF PUBLIC HEALTH,

CENTER OF ENVIRONMENTAL HEALTH,

PRAGUE, CZECH REPUBLIC

 3AXYS VARILAB LTD., CZECH REPUBLIC

HUMAN EXPOSURE

TO ENDOCRINE DISRUPTERS (EDs)

IS WIDESPREAD AND IS CONSIDERED

TO POSE A GROWING THREAT

TO HUMAN HEALTH.

GROWING INTEREST IN HEALTH IMPLICATIONS OF THIS DEVELOPMENT CAN BE DEMONSTRATED BY PRESENT

EC AND US EFFORTS TO CO-ORDINATE STRATEGIC RESEARCH IN THIS FIELD.

EXTRAPOLATION OF DOSE/RESPOSE DATA

FROM BOTH EXPERIMENTAL ANIMALS

AND EPIDEMIOLOGY STUDIES HAS BEEN

LARGELY BASED ON MODELS ASSUMING

LINEAR CORRELATION AT LOW DOSES.

PRESENT DISCUSSION: • EXPOSURE ASSESSMENT - POOR EXPOSURE

DATA IN ECOLOGICAL STUDIES. FREQUENTLY ROUGH ESTIMATES DERIVED FROM CONTAMINATED ITEMS OF LOCAL FOOD BASKET SURVEYS.

• EXTRAPOLATION TO LOW DOSE/EXPOSURE BASED ON MODELS ASSUMING LINEAR CORRELATION INCLUDING NON-GENOTOXIC CARCINOGENS.

 

POLYHALOGENATED HYDROCARBONS

CAN BE TREATED AS EXAMPLES.

POLYHALOGENATED HYDROCARBONS: PCDDs/DFs & PCBs

EXPOSURE ASSESSMENT • EDs ABILITY TO CROSS THE PLACENTAL

BARRIERIN UTERO EXPOSURE OF THE DEVELOPING ORGANISM

 • EXPOSURE OF NEONATES DURING CRITICAL

DEVELOPMENTAL PERIODSBREAST-FED INFANTS EXPOSED TO EDs AT LEVELS 10-40 TIMES HIGHER THAN THOSE IN THE GENERAL POPULATION

OBJECTIVES:

THIS PRESENTATION SUMMARISES

AND REVIEWS THE DATA CONCERNING BIOMONITORING OF HUMAN EXPOSURE

TO PCDDs/Fs AND PCBs

IN THE CZECH REPUBLIC (CR)

BY PRESENTATION OF A DATA OF A PROJECT SUPPORTED BY THE MINISTRY OF

ENVIRONMENT OF THE CR.

METHODS:

TO PRODUCE COMPRABLE RESULTS WITH THOSE FROM THE PREVIOUS WHO/ECEH STUDIES (1996) WE USED

THE SAME PROTOCOL WITH AN EXCEPTION OF POOLING OF THE BREAST MILK SAMPLES. THE INDIVIDUAL

SAMPLES WERE USED FOR FURTHER IMPROVEMENT OF EXPOSURE ASSESSMENT OF INFANTS. CLEANED UP EXTRACTS OF BREAST MILK SAMPLES WERE ANALYSED

FOR PCDDs/Fs AND NON-ORTHO PCBs BY HR GC-MS CHROMATOGRAPHY (VG ULTIMA 2) AND PCB

CONGENERS BY GC-MS (VARIAN SATURN). DONORS WERE PRIMIPARE RESIDED IN 7 DIFFERENT AREAS OF THE CR. THEY WERE INCLUDED IN THE STUDY ONLY

AFTER HEAVING VERBAL AND WRITTEN INFORMATION AND GIVEN WRITTEN CONSENT.

Estimated exposure of breast-fed infants to total WHO-TEQ (median values)

0,0

50,0

100,0

150,0

200,0

250,0

300,0

UH1 UH2 UL KO Praha KL Telč LB

WH

O-T

EQ

pg

/kg

b.w

.

PCDDs PCDFs nonorto PCB monoortoPCB

0,0 10,0 20,0 30,0 40,0 50,0 60,0 70,0 80,0 90,0 100,0

UH1

UH2

UL

KO

Praha

KL

Telč

LB

Ranges of exposure of breast-fed infants to WHO-TEQ from PCDDs (pg/kg b.w.)

0,0 50,0 100,0 150,0 200,0 250,0 300,0 350,0

UH1

UH2

UL

KO

Praha

KL

Telč

LB

Ranges of exposure of breast-fed infants to WHO-TEQ from PCDFs (pg/kg b.w.)

0,0 100,0 200,0 300,0 400,0 500,0 600,0

UH1

UH2

UL

KO

Praha

KL

Telč

LB

Ranges of exposure of breast-fed infants to WHO-TEQfrom non-orto PCBs (pg/kg b.w.)

0,0 100,0 200,0 300,0 400,0 500,0 600,0

UH1

UH2

UL

KO

Praha

KL

Telč

LB

Ranges of exposure of breast-fed infants to WHO-TEQ from mono-orto PCBs (pg/kg b.w.)

Estimated exposure of breast-fed infants to total PCB (median values)

14,3

4,5

6,7

4,43,9

2,82,0

2,6

0,0

2,0

4,0

6,0

8,0

10,0

12,0

14,0

16,0

UH1 UH2 UL KO Praha KL Telč LB

mg

/kg

b.w

.

0,0 10,0 20,0 30,0 40,0 50,0 60,0 70,0

UH1

UH2

UL

KO

Praha

KL

Telč

LB

Ranges of exposure of breast-fed infants to total PCBs (mg/kg b.w.)

0 200 400 600 800 1000 1200

UH1

UH2

UL

KO

Praha

KL

Telč

LB

Ranges of exposure of breast-fed infantsto total WHO-TEQ (pg/kg b.w.)

RESULT:

THE UNCERTAINTY IN CONTEMPORARY BACKGROUND LEVELS OF PCBs AND PCDDs/Fs AND

THE UNKNOWN EXTEND OF THE BODY BURDEN RESULTED IN INCLUDING THE SYSTEMATIC

MONITORING OF PCBs IN HUMAN FLUIDS AND TISSUES INTO THE SYSTEM OF MONITORING THE

ENVIRONMENTAL IMPACT ON POPULATION HEALTH OF CR SINCE 1994. THE RESULTS OF Σ 81 SAMPLES ANALYSIS OBTAINED WERE USED FOR EXPOSURE

ASSESSMENT OF THE BREAST-FED CHILDREN IN THE SELECTED LOCALITIES COMPARABLE WITH

RESULTS OF WHO/ECEH EUROPEAN MULTICENTRIC ROUND STUDIES.

DIFFICULTY IN USING

THE PRESENTED DATA AVAILABLE FOR HEALTH RISK ASSESSMENT:

REALISTIC EXPOSURE ASSESSMENT

IN ADULTS BASED CONSIDERED AS APPROPRIATE ON BLOOD LEVELS ONLY.

CONCLUSIONS:• DESPITE THE PRESENCE OF PCBs, PCDDs AND

PCDFs IN HUMAN MILK,

BREAST-FEEDING SHOULD BE ENCOURAGED.

• CONVINCING EVIDENCE OF THE BENEFITS

OF HUMAN MILK TO THE OVERALL HEALTH AND DEVELOPMENT OF THE INFANT.

CONCLUSIONS:

THE DATA PRESENTED TILL NOW DOES NOT CONFIRM IDEAS ABOUT WIDESPREAD EXCESSIVE

EXPOSURE OF CZECH POPULATION TO POLYCHLORINATED BIPHENYLS VIA

CONTAMINATION OF A FOOD BASKET EXCEPT OF THE LIMITED LOCALITIES. HOWEVER, THE QUESTION IF AND TO WHAT EXTENT THE

PRESENT HEALTH STATUS OF CZECH POPULATION MIGHT BE INFLUENCED BY THE

PAST EXPOSURE TO POLYHALOGENATED HYDROCARBONS REMAINS TO BE ASSESSED.

ACKNOWLEDGEMENT:

THE AUTHOR ACKNOWLEDGES DEVOTED

COLLABORATION OF COLLEAGUES ON THE RESEARCH

GRANTS SUPPORTED BY THE CZECH MINISTRY

OF ENVIRONMENT, SUPPORTING PROJECT VaV 520/1/99

& PARTIAL SUPPORT BY THE PROJECT LN00B107,

MINISTRY OF EDUCATION OF THE CZECH REPUBLIC.

ADDRESS FOR CORRESPONDENCE: 

Prof. VLADIMÍR BENCKO, M.D., Ph.D.CHARLES UNIVERSITY OF PRAGUE

FIRST FACULTY OF MEDICINEINSTITUTE OF HYGIENE & EPIDEMIOLOGY

STUDNIČKOVA 7CZ 128 00 PRAGUE 2CZECH REPUBLIC

TEL/FAX +420224919967E-MAIL: VBENCKO@LF1.CUNI.CZ