Figure 2

Concentrations of cobalt (Co) and vitamin B12 (B12) in the human fetal liver. (A) and (B) show the effects of sex and maternal smoking on Co and B12, respectively. The ratio between B12 and Co (C) was lower in females and increased to male levels by smoke-exposure in females. Circulating fetal cysteine (D) and homocysteine (E) concentrations were significantly higher in male fetuses and this was lost when the mothers smoked. Data from individual fetuses (A–D: 11–16 fetuses per group; E–F: 13–17 fetuses per group) are shown, and the horizontal bar represents the mean of the group. Significant differences between groups are indicated by letters in the boxes above each graph. Within each element or compound, groups that do not share a letter are significantly (P <0.05) different. NSm, represents control fetuses from non-smoking mothers; Sm, represents smoke-exposed fetuses from mothers who smoked during pregnancy. Fetal sex is denoted by the appropriate symbol.