Increased blood lead and decreased calcium levels during pregnancy: a prospective study of Swedish women living near a smelter.

Abstract

OBJECTIVES: The purpose of this study was to monitor blood lead in a northern Swedish cohort of mothers and children during pregnancy and at birth. METHODS: Blood lead was analyzed during pregnancy and in the umbilical cords of 290 women living near a smelter and in 194 control subjects. RESULTS: During pregnancy, there were statistically significant overall increases in blood lead concentrations by 20% and 15% in the smelter and reference areas, respectively. Mean maternal blood lead concentrations at delivery were 0.15 mumol/L (3.11 micrograms/dL) in the smelter area and 0.13 mumol/L (2.69 micrograms/dL) in the control area. Umbilical cord blood lead levels were 80% to 87% of the maternal levels. Blood lead levels were influenced by place of residence, employment at the smelter, smoking, and wine consumption. Maternal serum calcium levels decreased during pregnancy and were significantly lower than those of the newborns. CONCLUSIONS: An increase in blood lead concentrations was found during pregnancy, despite increased blood volume and unchanged or decreasing environmental lead levels. The mobilization of lead from bone during pregnancy may explain the increase.

Organochlorine and heavy metals in newborns: Results from the Flemish Environment and Health Survey (FLEHS 2002–2006)

“…The influence of area of living is reported in many other studies (Bjerregaard and Hansen, 2000;Butler Walker et al, 2006;Butler Walker et al, 2003;Laden et al, 1999;Lagerkvist et al, 1996) It was not expected that the residents of the rural areas would show the highest levels of OCs in cord blood (Fig. 2).…”

“…Embryonic development or physiological changes accompanying pregnancy, may impact mobilization from lipid reserves. Also Pb, accumulated in bone tissue over more than 20 years, may be mobilized during pregnancy and contribute to fetal exposure (Gulson et al, 1997;Lagerkvist et al, 1996;Raghunath et al, 2000). Cd accumulates in the human body, in particular in the kidney and liver and has an elimination half-life of 10-30 years (Jarup et al, 1998).…”

“…OCs are easily transferred to the fetus with rates around 25-30% expressed on fresh weight base (Bjerregaard and Hansen, 2000;Butler Walker et al, 2003;Covaci et al, 2002;Soechitram et al, 2004) or around 80% on lipid weight basis (Jaraczewska et al, 2006). Umbilical cord blood levels of Pb have been reported to be about 85 to 90% of those of the mother (Lagerkvist et al, 1996). For Cd, different transfer percentages of 10% (Osman et al, 2000) to 81% (Raghunath et al, 2000) were observed.…”

Characterizing Golden Eagle Risk to Lead and Anticoagulant Rodenticide Exposure: A Review

“…Although there is no direct evidence for this in humans, an increase in lead absorption may contribute, along with other mechanisms (e.g., increased mobilization of bone lead), to the increase in PbB that has been observed during the later half of pregnancy (Gulson et al 1997b(Gulson et al , 1998b(Gulson et al , 2004Lagerkvist et al 1996;Rothenberg et al 1994b;Schuhmacher et al 1996).…”

“…Analysis for kinetics of changes in the stable isotope signatures of blood lead in pregnant women as they came into equilibrium with a novel environmental lead isotope signature indicated that 10-88% of the lead in blood may derive from the mobilization of bone lead stores and approximately 80% of cord blood may be contributed from maternal bone lead (Gulson 2000;Gulson et al 1997bGulson et al , 1999cGulson et al , 2003. The mobilization of bone lead during pregnancy may contribute, along with other mechanisms (e.g., increased absorption), to the increase in lead concentration that has been observed during the later stages of pregnancy (Gulson et al 1997b;Lagerkvist et al 1996;Schuhmacher et al 1996). Bone resorption during pregnancy can be reduced by ingestion of calcium supplements (Janakiraman et al 2003).…”