Exposure to lead is a serious issue in developing countries undergoing industrial transition. Wegdan Lotfy* describes one project where inherited health risks were addressed Shoubra El-Kheima has gained notoriety as one of the most polluted districts in Greater Cairo due to the numerous industrial zones sandwiched between residential blocks. The industries were constructed years ago when the area was considered remote. Over the years, and as Egypt's population exploded, families started moving out to the area, building their homes in the vicinity of these factories, oblivious to the dire consequences. As population density increased, schools and hospitals were erected and environmental problems consequently became interwoven in the community as a whole. Of particular significance is the lead smelting industry. Policymakers together with public health officials lacked the appropriate means to properly identify the risks and exposure potential of this heavy metal on the Egyptian environment. Acid storage batteries used for vehicles can be charged and recharged before they are worn out. Worn out car batteries serve as the raw material for secondary smelters where lead plates are smelted and then refined with metal additives and made into lead ingots and lead pipes. A number of secondary lead smelters of old-battery recycling plants were still operating in Shoubra El-Kheima. The private sector lead smelting industry in Cairo has traditionally been located in Shoubra El-Kheima, where 65 per cent of Egypt's lead production is found. The largest of these smelters is the Awadallah Secondary Lead Smelter, which began operations in 1979 and ceased smelting activities in 2001 after the government of Egypt encouraged smelters to move to new industrial zones in Abu Zaabal and to install up-to- date technology to reduce harmful emissions emanating from the smelting process. An 85 per cent decrease of emitted particulate matter and lead was attained as compared to the 1999 values. The hazardous effects of lead Lead is known to be one of the most hazardous elements due to its cumulative toxic health effects on workers, residents and particularly children. Once lead is absorbed, whether by inhalation or digestion, it circulates in the blood. From blood, lead is able to diffuse into soft tissue and major organs: the liver, kidneys, brain and bone marrow. These organs are the primary sites of the cellular toxic effects of lead. Iron deficiency and calcium deficiency are known to enhance lead absorption. Lead's toxic effects are encountered during both short and long term exposure and its clinical manifestations vary with age and gender. The adverse health problems are numerous and are exhibited primarily in the blood forming and nerve tissues: in the blood, by inhibiting the enzymes responsible for the biosynthesis of hemes; whereas lead's invasion of the central and peripheral nerve cells is governed by the amount of lead in the blood. If the blood- lead level is in the 5�g/dL range (five microgram per decilitre) it decreases nerve conduction velocity, while higher values are associated with the degeneration of the nerve cell itself. The contribution of lead to other health issues is evident in growth impairments, auditory pathway and kidney function deterioration, to name a few. Women are more vulnerable to lead's toxic health effects than men. Elderly women in particular experience a blood-lead level rise after first initial intake. This is due to the remobilisation of lead that accompanies the resorption of bones, thus causing osteoporosis. The body's lead burden is presumed to be very large because only around five per cent is in the blood circulation. For pregnant women, lead's diffusion across the placenta contributes to lead poisoned offspring; foetal blood lead levels are more than 80 per cent of the blood-lead level of mothers. Also bone mobilisation allows elevated lead levels during pregnancy. Lead poisoned women exhibit a high rate of spontaneous abortions and stillbirths. Age plays a vital role in the amount of lead to be absorbed by the body. Only 10 per cent of ingested lead is absorbed in adults, whereas children absorb as much as 50 per cent of ingested lead. Children are more vulnerable to all the neurotoxic effects of lead compared to adults. Exposing them to lead during critical stages in their neurodevelopment results in changes of their cerebral architecture and disrupts the integrity of the blood-brain barrier. The cleanup project The Ministry of Environmental Affairs initiated, through the Egyptian Environmental Policy Program (EEPP) together with two consecutive USAID projects, the Cairo Air Improvement Project (CAIP) and the Livelihood and Income from the Environmental Program (LIFE), an investigation of these environmental problems and implemented for the first time in Egypt a system by which polluted areas are targeted, studied and remediated. Preliminary studies were undertaken to establish the state of the site in order to properly estimate the extent of lead pollution. Soil, dust and water samples were collected and analyzed within a one-kilometre radius of the Awadallah smelter that was taken as the focal point. Exceedingly high levels of lead contamination were confirmed to exist in the targeted region. The study showed evidence that the blood-lead level of some children and females in certain areas were above 25 g/dL and that 100 per cent of the females and 84 per cent of the children in these areas exceeded the threshold limit, that is to say greater than 10 g/dL. Residential sections in the direct vicinity of the smelters were found to exhibit the most hazardous environmental conditions. Lead was also found in mothers' milk in the preliminary work performed by CAIP, this being in accordance with previous literature. It was clear that residents in the study area were not aware of the precautions they should be taking to avoid exposure to the hazards of lead contamination. An urgent need for remediation intervention and public awareness programmes focusing on how to minimise the hazardous effects of exposure to lead was identified. In August 2004, USAID designed a lead cleanup component under LIFE, to clean up five smelter locations and nearby schools. * The writer is assistant professor at Al-Ahram Canadian University.
