Human Exposure to Lead in Chile(p. 93-94)

Andrei N. Tchernitchin, Nina Lapin, Lucý´aMolina, Gustavo Molina, Nikolai A. Tchernitchin, Carlos Acevedo, and Pilar Alonso Contents

I. Introduction 94
II. Primary Sources 96
III. Lead in Household Paints 97
IV. Lead in Gasoline 99
V. Lead Exposure Clusters 108
A. The N˜ uble case: Lead in Wheat Flour 108
B. Other Clusters 112
VI. Special Cases 113
A. The Antofagasta Case: Powdered Lead Mineral Concentrates from Bolivia 113
B. The Arica Case: Toxic Wastes from Sweden and Mineral Concentrates from Bolivia 120
VII. Other Sources 127
VIII. Lead in Soil 129
IX. Recommendations 130
Summary 133
Acknowledgments 135
References

I. Introduction

Lead has been used in human civilizations for about 5000 years and currently has many uses in modern technology. Its uses and toxic properties at high doses have been recognized since antiquity (Waldron 1973). Since the beginnings of lead use, evidence of lead poisoning has been found by medical historians, with dramatic effects on the destiny of ancient civilizations. The fall of the Roman Empire was related to the wide use of lead in paints, water distribution pipes, and wine storage vessels. It was suggested that the declining birthrate, the epidemics of stillbirths and miscarriages, and apparently the increased incidence of psychosis in Rome’s ruling class, which may have been at the root of the Empire’s dissolution, were a result of exposure to lead in food and wine (Gil.llan 1965). It has been recently proposed that similar or additional effects of human population exposure to lead may contribute to the decline of current societies through lead induced impairment of intelligence (Needleman et al. 1979, Banks et al. 1997), increased tendency to addictions to drug abuse (Tchernitchin and Tchernitchin 1992, Tchernitchin et al. 1999), increase in delinquent behavior (Needleman et al. 1996), or psychological changes such as behavioral dif.culties at school (Byers and Lord 1943, Banks et al. 1997).

Acute exposure to high levels of lead causes serious diseases such as lead encephalopathy, which includes brain swelling and can evolve to coma and death. This is not a frequent situation, but may occur in children accidentally exposed to high lead levels, as well as in occupational accidents and attempted suicides.

Chronic exposure to lower levels of lead, which usually does not cause acute symptoms or signs, is a frequent situation affecting urban populations, occupationally exposed workers, and people living in the vicinity of polluting sources. In adults, chronic exposure to lead causes progressive damage to the central and peripheral nervous systems (Needleman et al. 1979, Banks et al. 1997), a moderate increase in blood pressure (Staessen et al. 1994), and effects on both male and female reproductive systems in humans (Winder 1993) as well as in experimental animals (Ronis et al. 1996, Tchernitchin et al. 1998, 2003), causing mainly infertility and an increased abortion rate. It also affects the hematopoietic system (Grandjean et al. 1989, Pagliuca et al. 1990, Graziano et al. 1991), for review of lead interference with the biosynthesis of heme, see NAS-NRC (1972). It depresses thyroid function (Tuppurainen et al. 1988) and causes nephropathy (Weeden et al. 1975, 1979, Ong et al. 1987, Cooper 1988, Cardenas et al. 1993), intestinal colic, gastrointestinal symptoms (Baker et al. 1971, Pagliuca et al. 1990), and damage to the immune system, as shown in humans and experimental animals (Ewers et al. 1982, Jaremin 1983, Cohen et al. 1989, Koller 1990, Lang et al. 1993, Tchernitchin et al. 1997, Villagra et al. 1997). It may also cause effects on chromosomes (Schmid et al. 1972, Deknudt et al. 1973, Al-Hakkak et al. 1986), increase mortality rate (Cooper 1988), and decrease life expectancy.