Flame retardants in placenta and breast milk and cryptorchidism in newborn boys.
BACKGROUND
Polybrominated diphenyl ethers (PBDEs) are widely used in Western countries.


OBJECTIVE
Because the prevalence of cryptorchidism appears to be increasing, we investigated whether exposure to PBDEs was associated with testicular maldescent.


METHODS
In a prospective Danish-Finnish study, 1997-2001, all boys were examined for cryptorchidism. We analyzed whole placentas (for 95 cryptorchid/185 healthy boys) and individual breast milk samples (62/68) for 14 PBDEs and infant serum samples for gonadotropins, sex-hormone binding globulin, testosterone, and inhibin B.


RESULTS
In 86 placenta-milk pairs, placenta PBDE concentrations in fat were lower than in breast milk, and a larger number of congeners were nondetectable. There was no significant difference between boys with and without cryptorchidism for individual congeners, the sum of 5 most prevalent, or all 14 congeners. The concentration of PBDEs in breast milk was significantly higher in boys with cryptorchidism than in controls (sum of BDEs 47, 153, 99, 100, 28, 66, and 154: median, 4.16 vs. 3.16 ng/g fat; p < 0.007). There was a positive correlation between the sum of PBDEs and serum luteinizing hormone (p < 0.033). The sum of PBDEs in breast milk did not differ between Denmark and Finland (median, 3.52 vs. 3.44 ng/g fat), but significant differences in some individual congeners were found.


CONCLUSIONS
Two different proxies were used for prenatal PBDE exposure, and levels in breast milk, but not in placenta, showed an association with congenital cryptorchidism. Other environmental factors may contribute to cryptorchidism. Our observations are of concern because human exposure to PBDEs is high in some geographic areas.
Main
Katharina Maria
KM
University Department of Growth and Reproduction, Rigshospitalet, Copenhagen, Denmark. katharina.main@rh.regionh.dk
Kiviranta
Hannu
H
Virtanen
Helena Eeva
HE
Sundqvist
Erno
E
Tuomisto
Jouni Tapio
JT
Tuomisto
Jouko
J
Vartiainen
Terttu
T
Skakkebaek
Niels Erik
NE
Toppari
Jorma
J
D000328:Adult; D016022:Case-Control Studies; D003456:Cryptorchidism / Q000139:chemically induced / Q000453:epidemiology*; D003718:Denmark / Q000453:epidemiology; D004781:Environmental Exposure; D005260:Female; D005387:Finland / Q000453:epidemiology; D005411:Flame Retardants / Q000032:analysis / Q000633:toxicity*; D055768:Halogenated Diphenyl Ethers; D006801:Humans; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D008895:Milk, Human / Q000737:chemistry*; D010647:Phenyl Ethers / Q000032:analysis / Q000633:toxicity*; D010920:Placenta / Q000737:chemistry*; D011075:Polybrominated Biphenyls / Q000032:analysis / Q000633:toxicity*; D011247:Pregnancy; D011446:Prospective Studies; D013223:Statistics as Topic
D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D010647:Phenyl Ethers; D011075:Polybrominated Biphenyls; C086401:pentabromodiphenyl ether