POTENTIAL CRYPTORCHIDISM IN
CHILDREN FROM A DIOXIN (TCDD)-CONTAMINATED REGION IN SOUTHERN KAZAKHSTAN
Chuvakova
T1, Hooper K2
1Physicians Institute of Postgraduate Training,
Kazakhstan Ministry of Health, Almaty, Kazakhstan
2Hazardous Materials Laboratory, California
Environmental Protection Agency, Berkeley, CA 94704 USA
Objective: In a pilot study, to evaluate the potential for
testicular effects among 11 male children ages 3-4 years living in a
dioxin-contaminated region.
Methods:
Study design. In earlier studies, high levels of 2, 3, 7,
8 - tetrachlorodibenzo-p-dioxin (TCDD) were measured in breast milk samples
collected from first-time mothers (“primiparae”) living in a cotton-growing
region in southern Kazakhstan (1-3).
The exposures to TCDD appear to have been chronic, environmental and
long-term. Testicular effects of these TCDD exposures were compared among
male children of mothers with either high (>15 pg/g fat) or low (<10
pg/g fat) TCDD levels in breast milk. The evaluator was blind as to whether
the child belong to the HD or LD group.
Results:
Eleven male children (8 in high
dose (HD) group and 3 in the low dose (LD) group) ages 3-4 years were evaluated. The proportion of male children with
cryptorchidism was higher in the HD group (6/8) than in the LD group (0/3).
Another HD male child had a cyst in the seminiferous tubules. Thus,
testicular effects were seen in 7 of 8 HD male children, and not seen in
the 3 LD children. The dioxin (TCDD) levels in breast milk of the mothers
of the HD children, measured 2-3 years earlier, were (pg/g fat):
cryptorchidism 72, 60, 51, 50, 43, 41, 18; cyst in seminiferous tubule 116.
The comparable levels for the LD group were (pg/g fat): 10, 9, 8. TCDD
levels in the US are in the 2-5 pg/g range.
Conclusion: A high
proportion of children in the HD group have cryptorchidism, particularly
for 3-4 year olds. There was no selection bias for entry into the initial
study population of primiparae. The range and distribution of ages, as well
as the residential histories, were similar for the HD and LD groups.
Because the numbers are small in this pilot study, especially in the LD
group, the study will be extended to include larger numbers of male
children in the LD group.
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Sharmanov T, Hayward D, Grassman J. Environ. Health Perspect.
106:1-10(1998).
3. Hooper K, Chuvakova T, Kazbekova G, Hayward D, Tulenova A,
Petreas MX, Wade TJ, Benedict K, Cheng YY, Grassman J; Environ. Health Perspect.
1999, 107, 447-457.