Reduction in Exposure to Lead from Drinking Water and its Effect on Blood Lead Concentrations

Abstract

<jats:p> 1 The water supply in Ayr (Scotland, UK) was plumbosolvent and many dwellings in Ayr contained lead pipes. In 1981 treatment of the water supply to reduce its plumbosolvency was initiated. Measurements of water and blood lead concentrations were made before and subsequent to the treatment. Most of the measurements made before and after water treatment began were made on water samples from the same dwellings and blood samples from the same women. </jats:p><jats:p> 2 Water treatment produced a sharp fall in water lead concentrations and a decrease in the median blood lead concentration from 21 to 13 μg/100 ml. </jats:p><jats:p> 3 Two women had higher than expected blood lead concentrations, both these women had been removing old paint. </jats:p><jats:p> 4 Women who had lead pipes removed from their dwellings all showed substantial decreases in their blood lead concentrations. </jats:p><jats:p> 5 The curvilinearity of the relation between blood lead and water lead concentrations is confirmed. Even relatively low (&lt;40 μg/l) water lead concentrations may make a substantial contribution to blood lead concentrations. </jats:p>

Bioavailability of soilborne lead in adults, by stable isotope dilution.

“…Therefore, as a concession to practicality, we administered the soil as a bolus and recognized the possible limitations of this dosing regimen. However, the comparatively small tracer dose of Pb administered, even as a bolus, seems unlikely to result in saturable kinetics (8,30).…”

Influence of acid rain upon water plumbosolvency.

“…The nonlinear association between lead in water supplies and lead in blood guarantees an increasing enhancement of lead exposure abatement as concentrations fall. This is evident even at the lowest levels of exposure (35,36 Thanks are due to all of the willing ladies who freely consented to take part in these studies, to the laboratory staffs who carried out the lead analyses, and to the members of the Health Boards and Hospital Staffs, and Strathclyde Water Board who collected the samples. Financial assistance was given in the various phases of these studies by The Scottish Home and Health Department, Department of the Environment, the Ministry of Agriculture, Fisheries and Food, and the Commission of the European Communities.…”

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

“…Numerous observations of nonlinear relationships between blood lead concentration and lead intake in humans provide support for the existence of a saturable absorption mechanism or some other capacity limited process in the distribution of lead in humans Sherlock and Quinn 1986;Sherlock et al 1984) (see Section 3.4.1 for discussion of saturable uptake of lead in red blood cells).…”

“…Saturable mechanisms of absorption have been inferred from measurements of net flux kinetics of lead in the in situ perfused mouse intestine, the in situ ligated chicken intestine, and in in vitro isolated segments of rat intestine Barton 1984;Flanagan et al 1979;Mykkänen and Wasserman 1981 (Bronner et al 1986;Fleming et al 1998b;Gross and Kumar 1990;Teichmann and Stremmel 1990). Numerous observations of nonlinear relationships between blood lead concentration and lead intake in humans suggest the existence of a saturable absorption mechanism or some other capacity-limited process in the distribution of lead in humans Sherlock and Quinn 1986;Sherlock et al 1984). In immature swine that received oral doses of lead in soil, lead dose-blood lead relationships were nonlinear; however, dose-tissue lead relationships for bone, kidney, and liver were linear.…”

“…The elimination half-time of lead in blood is approximately 30 days (Chamberlain et al 1978;); therefore, the lead concentration in blood relatively reflects, mainly, the exposure history of the previous few months and does not necessarily reflect the larger burden and much slower elimination kinetics of lead in bone (Graziano 1994;Lyngbye et al 1990b). The relationship between lead intake and PbB is curvilinear; the increment in PbB per unit of intake decreases with increasing PbB Sherlock and Quinn 1986;Sherlock et al , 1984. Lead intake-blood lead relationships also vary with age as a result of age-dependency of gastrointestinal absorption of lead, and vary with diet and nutritional status accounting for some of these factors and thereby provide a better measure of long-term exposure .…”