Relationship of Lead, Mercury, Mirex, Dichlorodiphenyldichloroethylene, Hexachlorobenzene, and Polychlorinated Biphenyls to Timing of Menarche Among Akwesasne Mohawk Girls

Abstract

ABSTRACT. Background. Children are commonly exposed at background levels to several ubiquitous environmental pollutants, such as lead and persistent organic pollutants, that have been linked to neurologic and endocrine effects. These effects have prompted concern about alterations in human reproductive development. Few studies have examined the effects of these toxicants on human sexual maturation at levels commonly found in the general population, and none has been able to examine multiple toxicant exposures. The aim of the current investigation was to examine the relationship between attainment of menarche and levels of 6 environmental pollutants to which children are commonly exposed at low levels, ie, dichlorodiphenyldichloroethylene (p,p-DDE), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), mirex, lead, and mercury.Methods. This study was conducted with residents of the Akwesasne Mohawk Nation, a sovereign territory that spans the St Lawrence River and the boundaries of New York State and Ontario and Quebec, Canada. Since the 1950s, the St Lawrence River has been a site of substantial industrial development, and the Nation is currently adjacent to a US National Priority Superfund site. PCB, p,p-DDE, HCB, and mirex levels exceeding the US Food and Drug Administration recommended tolerance limits for human consumption have been found in local animal species. The present analysis included 138 Akwesasne Mohawk Nation girls 10 to 16.9 years of age. Blood samples and sociodemographic data were collected by Akwesasne community members, without prior knowledge of participants' exposure status. Attainment of menses (menarche) was assessed as present or absent at the time of the interview. Congener-specific PCB analysis was available, and all 16 PCB congeners detected in >50% of the sample were included in analyses (Interna- , 153, 180, and 187). Probit analysis was used to determine the median age at menarche for the sample. Binary logistic regression analysis was used to determine predictors of menarcheal status. Six toxicants (p,p-DDE, HCB, PCBs, mirex, lead, and mercury) were entered into the logistic regression model. Age, socioeconomic status (SES), and BMI were tested as potential cofounders and were included in the model at P < .05. Interactions among toxicants were also evaluated.Results. Toxicant levels were measured in blood for this sample and were consistent with long-term exposure to a variety of toxicants in multiple media. Mercury levels were at or below background levels, all lead levels were well below the Centers for Disease Control and Prevention action limit of 10 g/dL, and PCB levels were consistent with a cumulative, continuing exposure pattern. The median age at menarche for the total sample was 12.2 years. The predicted age at menarche for girls with lead levels above the median (1.2 g/dL) was 10.5 months later than that for girls with lead levels below the median. In the logistic regression analysis, age was the strongest predictor of menarcheal status and SES was also a significa...

Hormone levels and sexual development in Flemish adolescents residing in areas differing in pollution pressure

“…However the high blood concentrations of lead and cadmium observed by Schroijen et al (2008) in adolescents from Antwerp and the Antwerp harbour could have contributed to the delay in sexual maturation observed for these adolescents. Indeed, high lead levels in blood were already reported to be associated to a delayed pubertal development in girls (Denham et al, 2005;Selevan et al, 2003Selevan et al, , 2004Wu et al, 2003). Among the female adolescents who participated in our biomonitoring study, Den Hond et al (submitted) observed a significant negative association between blood lead concentration and development of pubic hair (odds ratio for doubling of exposure is 0.65; p ¼ 0.020).…”

Internal exposure to pollutants and sexual maturation in Flemish adolescents

“…In some other studies, similar results were reported. Higher serum concentrations of the potentially estrogenic PCB congeners 52, 70, 101 [ þ 90] and 187 were associated with a significantly greater probability of having reached menarche (Denham et al, 2005), whereas in Yucheng boys accidentally exposed to high levels of PCBs and polychlorinated dibenzofurans, shorter penile length suggesting pubertal delay was reported (Guo et al, 2004). Delayed initiation of breast development was found in girls with higher prenatal dioxin exposure .…”

Menarche in women with high exposure to persistent organochlorine pollutants in utero and during childhood

“…In a recent cross-sectional study of Akwesasne Mohawk Girls, a high concentration of blood PCB indicated a higher probability of having reached menarche, i.e. that highly exposed females tended to be younger at menarche (Denham et al 2005). Contradictory to this study, Vasiliu et al (Vasiliu et al 2004) found that in utero exposure to DDE, but not PCB, resulted in reduced age at menopause.…”

“…Studies on women with high consumption of fish from the Baltic Sea or from the Great Lakes have suggested that high dietary exposure to POPs may cause damage to the female reproductive system, measured as time to pregnancy and delayed conception (Buck et al 2000, McGuinness et al 2001, as well as menstrual cycle length (Axmon et al 2004, Mendola et al 1997. Furthermore, increasing blood levels of PCB may be associated with decreasing age at menarche (Denham et al 2005). Animal studies have found that in utero exposure to the PCB congener 2,2'4,4',5,5'-hexachlorobiphenyl (CB-153), but not the congener 3, 3',4,4',, tend to delay onset of puberty in female goats (Lyche et al 2004).…”