Lead is a harmful heavy metal
Lead is a naturally occurring metal. Its chemical and physical characteristics, such as its malleability, low melting point and resistance to corrosion, make it amenable to a range of uses. Lead is also highly toxic to humans and the environment. It is a cumulative toxicant particularly hazardous to young children and pregnant women. No safe level of lead exposure has been established. Once taken into the body, lead can cause permanent damage to the neurological and cardiovascular systems (UNEP & Pure Earth, 2019).
The main lead exposure and absorption route are inhalation, ingestion and dermal contact (ATSDR, 2007). Inhalation of fumes and dust is a major exposure route for people working with lead. Young children are particularly likely to be exposed through contaminated soil and air-borne household dust, because they spend a lot of time in one place playing on the ground with frequent hand-to-mouth activity. Lead exposure can result in learning disabilities, increased risk of antisocial behavior, reduced fertility and cardiovascular disease (WHO, 2017). A recent study by NYU School of Medicine shows that childhood exposure to lead causes economic loss of US $977 billion annually, 1.2 per cent of world GDP, by lowering intellectual ability in low and middle-income countries.
Lead Factsheet (UNEP, December 2022)
Uses of lead
Lead compound can add durability, opacity and color to paint. As of September 2019, 73 countries have adopted lead paint law to reduce the amount of lead added in paint to 90 ppm, the smallest quantity technically feasible. In 2009, the Global Alliance to Eliminate Lead Paint was established. It aims to catalyze efforts to prevent children’s exposure to lead from paints and to minimize occupational exposures to lead paint. Together with WHO, UNEP acts as co-secretariat and the US EPA is the chair of the Lead Paint Alliance.
Petrol
Historically, tetraethyl lead was added to petrol as an antiknock agent for better engine combustion. Through its uses, lead was dispersed on surface soils, resulting in the most significant historical source of human lead exposure.
Since 2002, UNEP has been supporting the Partnership for Clean Fuels and Vehicles (PCFV). This leading global public-private initiative has been promoting cleaner fuels and vehicles in developing and transition countries throughout its successful 10-year campaign to end the use of leaded petrol on a global scale.
Batteries account for more than 80 per cent of the global demand of lead. Improper recycling of used lead-acid batteries causes environmental pollution and health damage. The largest subsets of lead-acid batteries are for automotive applications (May, Davidson & Monahov, 2018). With increasing numbers of cars in use globally, this market will continue to expand. Lead-acid batteries are also required for industrial applications, fr example to ensure consistent energy for telecommunications and data networks. Since 2016, UNEP has been supporting efforts worldwide to promote the environmentally sound management of used lead-acid batteries.
Cookware and food storage
Lead has been identified in vessels used for cooking and food storage, from which it can transfer to food. Lead is incorporated into glazes and colorful decorations used on the surface of traditional pottery. In addition to ceramics, lead can be found in metal cookware. In many low- and middle-income countries, locally made aluminum cookware is common. Informal artisans use scrap metal from products such as waste engine parts, vehicle radiators, lead batteries and computer parts to make the cookware, incorporating whatever metals, including lead, in the final product.
Construction and plumbing
Since the Roman times, lead has been widely used as a material in water distribution pipes, fittings and solder in homes and central distribution networks. With no effort to universally replace these components, many remain in use today. Lead piping is less likely to be installed in water distribution systems today, because of the public health risk and the availability of alternatives, but some are still used in the chemicals industry. Other constructions still use lead in sheeting, radiation shielding, roofing and flashing.
Food
In addition to the ability of lead to end up in food through cookware or containers, lead has been added intentionally to food to enhance the color or sweetness of the product. In some countries, lead can also be found in high concentration as an adulterant in spices.
Cosmetics and dyes
Certain forms of lead are known to enhance color when included as additives. One sector of products in which lead may be found for pigmentation is cosmetics and dyes. One of the most widely used products containing lead is kohl. It can also be found in products such as eye shadows or hair dye products.
Fishing and ammunition
Despite regulatory actions in some countries, lead-based ammunition and fishing weights remain significant sources of lead in the environment, impacting both wildlife and human health through the food chain. For both of these applications, lead is an attractive material because of its high density, malleability and low cost. The Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) and the Convention on Migratory Species (CMS) - two international environment treaties behind World Migratory Bird Day - are also driving international efforts to tackle the global lead poisoning threat.
Principal uses of lead worldwide
Source: ILA, 2012
Useful information on lead
The initial listings are categorized by source. As work progresses additional categorization will be developed for specific work areas. Suggestions of additional information and resources for listing on the website (in any language) may be submitted to the secretariat.
