Paternal concentrations of dioxin and sex ratio of offspring

Abstract

SummaryBackground 2, 3,7,, is commonly considered the most toxic man-made substance. We have previously shown that high serum concentrations of TCDD in parents from Seveso, Italy, were linked to their having a relative increase in the number of female births after the parents exposure to a release of dioxin in 1976. We have continued the study to determine whether the parents' sex and/or age at exposure affected the sex ratio of their children. MethodsWe measured the TCDD concentrations in serum samples from potentially exposed parents collected in 1976 and 1977, and investigated the sex ratio of their offspring.Findings Serum samples were collected from 239 men and 296 women. 346 girls and 328 boys were born to potentially exposed parents between 1977 and 1996, showing an increased probability of female births (lower sex ratio) with increasing TCDD concentrations in the serum samples from the fathers (p=0·008). This effect starts at concentrations less than 20 ng per kg bodyweight. Fathers exposed when they were younger than 19 years of age sired significantly more girls than boys (sex ratio 0·38 [95% CI 0·30-0·47]).Interpretation Exposure of men to TCDD is linked to a lowered male/female sex ratio in their offspring, which may persist for years after exposure. The median concentration of dioxin in fathers in this study is similar to doses that induce epididymal impairments in rats and is about 20 times the estimated average concentration of TCDD currently found in human beings in industrialised countries. These observations could have important public-health implications.

Expressing urine from a gel disposable diaper for biomonitoring using phthalates as an example

“…Paternal consumption of cooking oil contaminated with PCBs, polychlorinated dibenzofurans (PCDFs), and polychlorinated dibenzo-p-dioxins (PCDDs) was reported to be associated with a significantly lower odds of having a male infant in Taiwan, China (del Rio Gomez et al, 2002). After an accidental release of dioxin in Seveso, Italy, exposed fathers under the age of 19 sired significantly more girls than boys compared with those fathers who were unexposed (Mocarelli et al, 2000). No significant change in the sex ratio was observed in Fukuoka and Nagasaki, Japan, following accidental contamination of rice oil with dioxinlike compounds (Yoshimura et al, 2001).…”

Reproductive outcome in a cohort of male and female rubber workers: a registry study

“…Another hypothesis is a more intensive early embryonic selection among males. An altered oVspring sex ratio has been observed in populations exposed to persistent organic compounds like PCBs (Karmaus et al 2002;Mocarelli et al 2000;Rogan et al 1999;Rylander et al1995), and pesticides (Hanke and Jurewicz 2004), albeit not consistently. Also, a reversed sex ratio has been observed after heavy methyl mercury pollution (Sakamot et al 2001).…”

Determinants of male health: the interaction of biological and social factors

“…For instance, in Serveso, a factory explosion exposed a significant population in central Europe to dioxin [21,22]. For many years later, those couples closest to the explosion had a distortion of the sex ratio of children born such that the number of male children born decreased to approximately 35% compared with an almost 50/50 ratio.…”