Academic journal article Bulletin of the World Health Organization

Environmental Lead Exposure: A Public Health Problem of Global Dimensions

Academic journal article Bulletin of the World Health Organization

Environmental Lead Exposure: A Public Health Problem of Global Dimensions

Article excerpt

Voir page 1074 le resume en francais. En la pagina 1075 figura un resumen en espanol.

Introduction

Lead, a ubiquitous and versatile metal, has been used since prehistoric times. It has become widely distributed and mobilized in the environment, and human exposure to and uptake of this non-essential element have consequently increased (1). At high levels of human exposure there is damage to almost all organs and organ systems, most importantly the central nervous system, kidneys and blood, culminating in death at excessive levels. At low levels, haeme synthesis and other biochemical processes are affected, psychological and neurobehavioural functions are impaired, and there is a range of other effects (2-4).

There is a long history of public exposure to lead in food and drink. Lead poisoning was common in Roman times because of the use of lead in water pipes and earthenware containers, and in wine storage. Lead poisoning associated with occupational exposure was first reported in 370 BC (5). It became common among industrial workers in the 19th and early 20th centuries, when workers were exposed to lead in smelting, painting, plumbing, printing and many other industrial activities. In 1767, Franklin obtained a list of patients in La Charite Hospital in Paris who had been admitted because of symptoms, which, although not recognized then, were evidently those of lead poisoning. All the patients were engaged in occupations that exposed them to lead (1, 5).

In 1839, Tanqueral des Planches described the symptoms of acute lead poisoning on the basis of 1213 admissions to La Charite Hospital between 1830 and 1838. His study was so thorough that little has subsequently been added to the clinical picture of the symptoms and signs of acute lead poisoning in adults (6). In the mid-19th century, occupational lead poisoning was a common disorder in the United Kingdom, and in 1882, following the deaths of several employees in the lead industry, a parliamentary enquiry was initiated into working conditions in lead factories (1, 6, 7). This resulted in the 1883 Factory and Workshop Act (Prevention of Lead Poisoning), which required lead factories to conform to certain minimum standards, e.g. the provision of ventilation and protective clothing.

Various adverse effects of lead exposure on human health have been recognized (1, 2, 5-10). The working environment in the lead industry, especially in developed countries, has been much improved (2, 5-9). Acute occupational lead poisoning has largely been controlled in developed countries through improved working conditions. However, concern has grown over the possible adverse effects of exposure to low levels of environmental lead. In particular, lead poisoning in children experiencing non-occupational exposure has attracted much attention (1, 3, 10).

In Australia, lead poisoning in children was first reported in 1892 (11), although it was not until 12 years later that the source, peeling lead-based paint, was identified in a series of ten children with lead colic (12). In 1943 a follow-up study of 20 schoolchildren in the USA who had experienced acute lead poisoning in infancy or early childhood found that exposure to environmental lead at levels insufficient to produce clinical encephalopathy was associated with long-term deficits in neuropsychological development (13). Case-control studies on mental retardation (14) and hyperactivity (15) in relation to environmental lead exposure showed that children who survived acute lead intoxication were often left with severe deficits in neurobehavioural function. It was subsequently recognized that longer-terms sequelae were not limited to people affected by excessive exposure but also occurred in children who experienced relatively low-level exposure.

Much research over the last 30 years has demonstrated adverse health effects of moderately elevated blood lead levels, i.e. below 25 [micro]g/dl. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.