Heavy metal exposure causes countless deaths and disabilities. The diverse range of sources and adverse health effects of heavy metals – including lead, arsenic, mercury, and cadmium – pose a complicated challenge for the world. We know that human activities are the primary driver of heavy metal production and pollution, contributing to disease and poverty on a global scale. Among heavy metals, lead is one of the most significant environmental health threats to children and pregnant women. The World Health Organization states that there is no known level of lead exposure that is considered safe, and lead poisoning in childhood is linked to cognitive impairment, violent crime in adulthood, and loss of economic productivity (Landrigan et al., 2017, p. 17).
Heavy metals have been used by humans for thousands of years. Their toxicity and tendency to accumulate in biological systems make them a significant health hazard. Some heavy metals such as copper and zinc have essential biological functions in miniscule amounts, but others – like lead, arsenic, mercury, and cadmium – can be life-threatening. Human exposure to toxic heavy metals persists globally, but the prevalence of heavy metal pollution is most notable in low- and middle-income countries (Järup, 2003, p. 167).
1. Lead exposure: lead is a major environmental threat because of its severe human health effects, and because of its global prevalence in air, water, dust and soil, and various manmade products. We measure lead exposure using the number of age-standardized disability-adjusted life years (DALYs) lost per 100,000 persons due to this risk.
|Heavy Metals Indicator|
|Lead Exposure||DALY rate|
Despite the natural occurrence of heavy metals, human activities are the main driver of heavy metal pollution. Even trace amounts can harm human health and the environment (Tchounwou, Yedjou, Patlolla, & Sutton, 2012). Adverse health effects and resistance to decay make heavy metals particularly hazardous pollutants. Although heavy metal toxicity is well-documented, managing its exposure and related risks is a challenge around the world (World Health Organization, 2011).
Depending on the context, the criteria used to define heavy metals can vary, but the term generally refers to metallic chemical elements with relatively high densities and toxic properties (Singh, Gautam, Mishra, & Gupta, 2011). According to the World Health Organization (WHO), there are 13 heavy metals of significance to human and environmental health: arsenic, cadmium, cobalt, chromium, copper, mercury, manganese, nickel, lead, tin, and titanium (World Health Organization, 2011). Some of these elements, like copper and zinc, are essential for sustaining life, but the vast majority have no safe exposure level. Toxic heavy metals cannot be biodegraded and accumulate in living organisms, causing serious diseases and disorders (G. Liu et al., 2014). Arsenic, cadmium, lead, and mercury are listed among the ten chemicals of major public concern by the WHO for their potential to be carcinogenic and inflict acute organ damage (Tchounwou et al., 2012).
Sources of heavy metals vary, but human exposure is largely attributed to mining and industrial operations, including metal refineries, petrochemical production, power plants, and electronics manufacturing. Contamination can also occur from diffuse sources, such as aging metal pipes, food contamination, sewage discharge, and leaching from landfills (UNEP-CEP, 2008). We see ongoing efforts to tackle the numerous sources of pollution, such as in large-scale mining. The 2016 meeting of the Intergovernmental Forum on Mining, Minerals, Metals, and Sustainable Development (IGF) concluded with its 62 member countries emphasizing the need for stronger legal frameworks that protect workers from mining-related pollution (Crawford, 2015). International efforts like this are helping establish stringent laws and testing requirements, but the countless sources of heavy metals and diverse pathways to human exposure make it difficult to effectively manage, much less eliminate, heavy metal pollution.
National and international heavy metal monitoring is not consistent. This reality emerges with particular force among developing countries where incidents of heavy metal exposure often go unnoticed or unreported, and public health laws are not properly enforced (Mamtani, Stern, Dawood, & Cheema, 2011). Confronted with a paucity of data that adequately captures the vast range of heavy metal occurrences, health threats, and environmental impacts, we chose lead as our proxy indicator to represent the impacts of heavy metal pollution on global sustainable development.
Lead and its negative health effects have been extensively studied by international bodies like the WHO. As a result there has been a steady reduction in contamination and disease burden, but occupational and community exposures to lead persist in many places around the world (Järup, 2003, p. 167; Landrigan et al., 2017, p. 17). According to the Institute for Health Metrics and Evaluation, in 2015 lead exposure accounted for nearly 0.5 million deaths and 9.3 million life years lost (DALYs) among adults 15 years and older, with the highest occurrence in developing regions (2017, p. 17).
Childhood exposure to lead is concerning because it causes permanent cognitive problems. WHO estimated in 2012 that lead was responsible for causing mild-to-moderate mental retardation of 0.6 million children annually (Landrigan et al., 2017, p. 17). Inhalation and ingestion are the primary ways in which lead enters the body. Once absorbed, lead can affect virtually every organ and reside in teeth and bones for decades (Meyer, Brown, & Falk, 2008). Children and the developing fetus of pregnant women are most susceptible to lead’s negative effects (World Health Organization, n.d.). Lead is particularly dangerous to children because they can absorb four to five times more lead than adults, and their brains and nervous systems are more sensitive to lead’s damaging effects (Meyer et al., 2008). Children who survive severe lead poisoning may suffer lifelong consequences, including behavioral disorders, physical disabilities, and learning impairments (World Health Organization, 2017b). These symptoms can result in lower school performance, higher risks of drug abuse and incarceration, and decreased economic productivity (Landrigan et al., 2017). During pregnancy, lead stored in maternal bone can mobilize into the blood stream, and lead can be transferred from mother to child. In addition, high levels of lead can cause miscarriage, premature birth, and fetal malformations (World Health Organization, 2017b). Prenatal and childhood exposures, as listed in Table 7–1, impose large and lasting costs, making prevention a priority for these vulnerable groups.
|Source: World Health Organization, 2010a, p. 38.|
|Drinking water systems with lead solder and pipes|
|Consumer products (e.g., traditional medicine, food cans, cosmetics, toys)|
|Incineration of lead-containing waste|
|Food, due to contaminated soil|
|Former industrial sites|
Countries are taking steps to address the many exposure sources, but more must be done in context of the environmental, social, and economic pillars comprising sustainable development.
Environmental: Lead can be found in the air, dust, soil, and water, as well as inside homes and various consumer goods. Natural levels of lead in soil range from 50 to 400 parts per million, but lead concentrations are much higher in some areas due to past use of leaded gasoline and past and present industrial emissions, notably from lead smelters (Environmental Protection Agency, 2017). Lead can also get in the air, with concentrations peaking near metal processing sites and waste incinerators. As an atmospheric pollutant, lead can travel long distances before settling to the ground and sticking to soil particles. It can then be re-suspended into the air, seep into the groundwater, or be absorbed by vegetation (2017). Although lead only makes up about 0.0013% of the earth’s crust, it is easily mined and refined, and human activities are to blame for the pervasive risks of lead exposure (Thomas Jefferson National Accelerator Facility, n.d.).
Plants are the foundation of our food chain, and given lead’s acute toxicity and resistance to decay, even the smallest concentration of lead uptake is cause for concern. Food continues to be the major source of lead exposure despite lead’s slow downward mobility in soil and low absorption rate by plant roots (D. Liu, Liu, Chen, Xu, & Ding, 2010). The lead content of plants is largely attributed to atmospheric deposition. Elevated lead concentrations have been recorded in plants nearby contaminated, industrially active sites (EFSA Panel on Contaminants in the Food Chain, 2010, p. 22). In the vicinities of ore deposits and factories that process and recycled lead, very high concentrations of lead are found even in the roots of vegetables (2010, p. 23). According to the European Food Safety Authority, cereal grains, vegetables, and tap water are the largest contributors to dietary lead exposure in the European population (2010, p. 30). There is significant variation in dietary lead content between and within countries. In Poland, vegetables, cereals, and meat products contributed the most to lead dietary exposure, whereas in Finland, the majority of lead exposure was from beverages and dairy products (2010, p. 26). The various sources of lead, numerous contaminated food groups, and different lead accumulation factors make national and international exposure mitigation a particularly difficult task.
Social: Socioeconomic factors can be a telling predictor of lead-related threats. Ethnic minority groups and low-income communities often face greater risk from multiple sources including increased likelihood of occupational hazards, exploitive child labor, substandard housing, and residential proximity to polluting industries (World Health Organization, 2010a, p. 35). A disproportionate burden of disease is placed on children, and an estimated 90% of children with elevated lead levels live in low-income regions (World Health Organization, 2010b, p. 35). Poor families are more likely to live in older houses with lead-based paint, and reside near industrial plants that handle lead, such as battery recyclers and smelters. In the most poverty-stricken countries, lead smelting factories employ the poorest populations. These groups are often unaware of the hazards and lack the financial means to receive adequate medical treatment (World Health Organization, 2010b, p. 35). Marginalized communities are therefore most vulnerable and often disproportionately affected by lead poisoning. Cultural customs also contribute to lead exposure factors. Traditional crafts like lead-tainted ceramics, homemade cosmetics, and herbal medicine can be routes of exposure. As global migration and markets increase the popularity of these items, exposures may expand beyond countries of origin and into higher income economies (2010b, p. 35).
Economic: Health impacts from lead exposure, including lifelong mental and physical impairments and direct medical treatment costs, place an overwhelming economic burden on society (World Health Organization, 2010a, p. 34). As shown in Map 7–1, estimates suggest that the loss in lifetime economic productivity from childhood lead exposure amounts to roughly $977 billion annually in low- and middle-income countries (Attina & Trasande, 2013). These findings represent the substantial economic burden that could be avoided if policies to prevent lead exposures are implemented.
Successful lead mitigation can have significant economic benefits (Grosse et al., 2002; Gould, 2009). The removal of lead from gasoline in the United States illustrates the magnitude of these benefits (Landrigan et al., 2017, p. 17). After the program was implemented in 1975, the average blood lead level of the U.S. population went down by over 90%, nearly eliminating childhood lead poisoning. Since 1980, cognitive ability in U.S. children has improved by 2–5 IQ points (2017, p. 46). The 2017 Lancet Commission report suggests that the intelligence gains over the lifespans of children born since 1980 may be valued at over $6 trillion (2017, p. 5). These benefits far outweigh the costs of phasing out lead as a fuel additive.
Global production of lead continues to rise. 85% of global lead demand is from the manufacture and recycling of lead-acid batteries, making this industry one of the primary sites of lead contamination (Attina & Trasande, 2013; World Health Organization, 2017a, p. 3)Despite continuing increases in global lead production, bans on the use of lead in petrol, paint, plumbing, and solder have produced substantial reductions in lead exposure. In 2002, lead was used in fuels in 82 countries, while only three countries continue to use leaded fuels today (World Health Organization, 2017c). The international transition to unleaded petrol in the last few decades, coupled with lead control measures, has subsequently decreased blood lead levels in the general population, and is considered a success story in heavy metal exposure mitigation (Landrigan et al., 2017).
Momentum has grown to establish lead paint laws globally. Each year, the international community promotes the phase out of leaded paint during the International Lead Poisoning Prevention Week. Organized by the Global Alliance to Eliminate Lead Paint, in 2017 the week-long initiative garnered participation from governments, academia, and civil society representing 42 countries to raise greater awareness on the issue (World Health Organization, 2017c). Although progress is being made – in 2016, seven countries reported new policies to address lead in paint, raising the global total to 66 countries – only a third of countries have legally binding controls on lead paint, signifying the ongoing health liability of lead in paint (World Health Organization, 2017b)and (United Nations Environment Programme, 2017b).
Both developed and developing countries are working to manage the adverse effects of toxic heavy metals like lead (Tchounwou et al., 2012). Although the Minamata Convention on Mercury provides a potentially replicable international framework for regulating other heavy metals, no such global framework currently exists for lead. A multisector approach will be necessary to assess the expansive scope of lead exposure. Developing countries should focus their attention on strengthening public health laws and enforcement mechanisms to mitigate exposure (Mamtani et al., 2011).
The safe and sustainable management of lead and other heavy metals plays an important role in achieving the Sustainable Development Goals (SDGs). Although lead is not explicitly mentioned, several SDGs address the mitigation of hazardous chemical exposure: SDG 3 (Ensure Health and Well-being), SDG 6 (Clean Water and Sanitation), SDG 8 (Decent Work and Economic Growth), SDG 12 (Responsible Consumption and Production).
Goal 3: Ensure healthy lives and promote well-being for all at all ages
Goal 3, Target 9: By 2030, substantially reduce the number of deaths and illnesses from hazardous chemicals and air, water and soil pollution and contamination
Goal 6: Ensure availability and sustainable management of water and sanitation for all
Goal 6, Target 3: By 2030, improve water quality by reducing pollution, eliminating dumping and minimizing release of hazardous chemicals and materials, halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally
Goal 8: Promote sustained, inclusive and sustainable economic growth, full and productive employment and decent work for all
Goal 8, Target 8: Protect labor rights and promote safe and secure working environments for all workers, including migrant workers, in particular women migrants, and those in precarious employment
Goal 12: Ensure sustainable consumption and production patterns
Goal 12, Target 4: By 2020, achieve the environmentally sound management of chemicals and all wastes throughout their life cycle, in accordance with agreed international frameworks, and significantly reduce their release to air, water and soil in order to minimize their adverse impacts on human health and the environment
Goal 12, Target 6: Encourage companies, especially large and transnational companies, to adopt sustainable practices and to integrate sustainability information into their reporting cycle
International organizations are working to address the challenges of heavy metal pollution. The WHO has been a leader in evaluating the health effects and coordinating partnerships to advance pollution abatement policies (Landrigan et al., 2017, p. 7).
Below is a list of some of the most relevant entities and regulations promoting chemical safety.
Many of the organizations’ specific roles are detailed in the 2017 report from The Lancet Commission on Pollution and Health: http://www.thelancet.com/commissions/pollution-and-health (2017, pp. 6–7).
World Health Organization
UN Development Programme
UN Environment Programme
UN Industrial Development Organization
International Labour Organization
Food and Agriculture Organization
Intergovernmental Forum on Chemical Safety
International Lead and Zinc Study Group
International Programme on Chemical Safety (IPCS): The International Programme on Chemical Safety (IPCS), established in 1980, is a joint venture of three organizations – the WHO, ILO and UNEP – implementing chemical safety goals. The WHO is the Executing Agency in charge of setting the scientific basis for the safe use of chemicals and to strengthen national capabilities for chemical safety (International Labour Organization, 2009a). http://www.who.int/ipcs/en/.
Global Alliance to Eliminate Lead Paint: The Global Alliance to Eliminate Lead Paint is a joint initiative led by the WHO and UNEP. Its objective is to prevent children’s exposure to lead from paints and minimizing occupational exposures to it. Its goal is to eliminate lead paint internationally by 2020 (World Health Organization, n.d.). http://web.unep.org/chemicalsandwaste/what-we-do/technology-and-metals/lead/global-alliance-eliminate-lead-paint.
Inter-Organization Programme for the Sound Management of Chemicals (IOCM): The IOMC facilitates international action to achieve the sound management of chemicals through the collaboration of its nine member organizations: Food and Agriculture Organization, International Labour Organization, Organization for Economic Cooperation and Development, United Nations Environment Programme, United Nations Industrial Development Organization, United Nations Institute for Training and Research, World Health Organization, World Bank, and the United Nations Development Programme (International Labour Organization, 2009b). http://www.who.int/iomc/en/.
Minamata Convention on Mercury: The Minamata Convention on Mercury is the first global, legally binding agreement designed to address contamination from a heavy metal. It was adopted in October of 2013 and entered into force in August 2017. Major commitments include a ban on new mercury mines and phase out of existing ones; the reduction of mercury use in several production processes; and controls on mercury release to land, water, and air (United Nations Environment Programme, 2017a). The first Conference of the Parties (COP1) to the Minamata Convention took place in September 2017, and although some technical disagreements remain, the Convention’s eventual implementation will help protect human health and the environment from mercury poisoning (Wagner, 2017). http://www.mercuryconvention.org/.
Strategic Approach to International Chemicals Management (SAICM): The UN Environment Programme is responsible for the oversight of SAICM, an international policy framework that aims to achieve the sound management of chemicals throughout their life cycles. SAICM’s “2020 goal” is to produce and use all chemicals without significant adverse impacts on human health or the environment by the year 2020 (United Nations Environment Programme, n.d.). http://www.saicm.org/.
The Codex General Standard for Contaminants and Toxins in Food and Feed (Codex Stan 193-1995): The Codex Stan 193-1995, most recently amended in 2016, is part of the global collection of standards and guidelines adopted by the Codex Alimentarius Commission (CAC). The Codex Stan 193-1995 ensures food safety by setting maximum permissible levels of arsenic, cadmium, lead, mercury, and tin. CAC was established by FAO and WHO to protect consumer health and regulate the international food trade. (Codex Alimentarius Commission, 2016). http://www.fao.org/fao-who-codexalimentarius/en/.
REACH (Registration, Evaluation, Authorization and Restriction of Chemicals): REACH is a regulation of the European Union, adopted in 2007 to improve the protection of human health and the environment from chemicals, while enhancing the competitiveness of the EU chemicals industry (European Chemicals Agency, n.d.). http://ec.europa.eu/environment/chemicals/reach/reach_en.htm.
Obstacles to measuring and ultimately eliminating lead pollution include the metal’s widespread presence in the environment, its ability to travel long distances, and weak or unenforced control measures (World Health Organization, 2011). Ideally, there would be standardized monitoring and data collection of lead contaminants in high risk zones, especially in low- and middle-income countries where significant exposure remains (Attina & Trasande, 2013). However, identifying these areas can be a challenge, and diagnosis can be difficult when exposure goes unnoticed and symptoms are relatively nonspecific (Haefliger, 2011).
To truly assess the global scale of lead exposure, there would need to be greater oversight of both point and non-point sources. However, there is inadequate information on the impact of non-point sources. Non-point sources include emissions from leaded aviation fuel and exposure from small scale, unregulated cottage industries, such as battery-recycling, craft making, and electronic waste recovery (World Health Organization, 2010a, p. 47).
Today, laboratories primarily assess lead exposure through the blood, measured as micrograms of lead per deciliter of blood. Although lead poisoning can also be measured using hair, teeth, bone, and urine, measuring the blood lead level (BLL) is widely viewed as the most reliable tool (Haefliger, 2011, pg 1). This is particularly true for screening young children whose BLL can indicate recent, acute exposure (World Health Organization, 2010a, p. 11). Less developed countries do not have the resources to conduct comprehensive surveillance, which means lead poisoning’s geographic and socio-economic factors have yet to be fully understood (Meyer et al., 2008). Nonetheless, lead, compared to other heavy metals, is one of the most well documented and researched pollutants. In light of the data available on lead globally, EPI has chosen to use lead exposure as a representative measure of the impact of heavy metal pollution worldwide.
Lead exposure is classified in two ways: acute and chronic lead poisoning. Acute toxicity is indicative of severe short-term exposure, whereas chronic toxicity describes repeated exposure, often at lower levels. Acute lead exposure is relevant to disease burden in children because their brain and nervous systems can absorb four to five times as much lead as adults (World Health Organization, 2017b). This sensitivity is further exacerbated by children’s innate exploratory behavior, resulting in greater ingestion of lead from soil, dust, paint, and other lead-contaminated objects (2017b). Chronic lead exposure is more pervasive in adults due to long-term occupational exposure, and manifested through increased blood pressure, kidney damage, and cardiovascular disease. Long-term exposure is not measured by BLL, and instead is measured as micrograms of lead per gram of bone. Lead that accumulates in the body over time is stored in bones, and the half-life of lead in blood is only about one month in adults (Payne et al., 2010). The consequences of lead exposure are measured in age-standardized disability-adjusted life years lost per 100,000 persons, the DALY rate.
The 2018 EPI relies on the latest and best available estimates of lead-related DALY rates.
The data on lead exposure DALY rates come from the Institute for Health Metrics and Evaluation’s Global Burden of Disease Study (GBD), which is the most comprehensive worldwide epidemiological study of lead exposure to date. Publicly accessible at http://www.healthdata.org/gbd, this study examines mortality and morbidity trends from 1990 to 2016 based on major diseases, injuries, and risk factors from lead exposure. Data for the GBD are drawn from 332 different studies on blood and bone samples, spanning the years 1964 to 2013. In 2015, the spatial-temporal modelling methodology was improved to more accurately predict blood lead in country-years with insufficient data (Forouzanfar et al., 2016).
While the GBD is the leading epidemiological study on environmental risks, several limitations in this indicator are worth noting. First, measuring lead exposure is a burdensome process, and the GBD must draw upon sparse datasets of blood and bone samples. Interpolation of exposure levels introduces uncertainty into the final DALY rate estimates. Second, the collection of tissue samples face a number of challenges, including unknown contaminants, lack of quality assurance, and the short half-life of lead in blood (Haefliger, 2011, p. 6; Payne et al., 2010). For adults exposed to long-term cumulative lead poisoning, the most valid method of assessment is noninvasive x-ray fluorescence measurement of bone lead concentration (Payne et al., 2010). Research is necessary to improve this technology, as this method is sensitive to slight movements and known to be difficult to use in practice. Finally, the GBD makes assumptions when linking lead exposure to actual health outcomes and the distribution of diseases and death across populations. The lead exposure indicator is the best available metric on this important environmental health risk, and future improvements will increase the accuracy of new estimates.
In January of 2016, the President of the United States declared a state of emergency in Flint, Michigan due to severe lead contamination of the city’s drinking water. In April 2014, the state government switched Flint’s water source from Lake Huron to the Flint River. As more polluted and corrosive water ran through the city’s aging lead service lines – the pipes connecting the water mains under the street to residences – lead began to leach into the drinking water at an unprecedented rate.
Flint is a majority African American city where 40% of residents live in poverty. The socioeconomically disadvantaged community was further stressed by drinking water with lead levels as high as 13,000 parts per billion (ppb) (Olson & Pullen Fedinick, 2016). Water with lead concentrations of 5,000 ppb is considered toxic waste by the U.S. Environmental Protection Agency (2016). Despite elevated lead concentrations, state officials dismissed citizens’ concerns for over a year, and the Environmental Protection Agency (EPA) failed to act even after multiple tests called for federal intervention (2016). This crisis illustrates how even the most politically stable, economically powerful countries are not immune to lead exposure and its tendency to harm the most vulnerable communities.
Flint is not an isolated case of lead contamination. In the United States, over 18 million people in 2015 were served by water systems violating the Lead and Copper Rule (Map 7–2). Established in 1991, the Lead and Copper Rule regulates lead and copper concentrations in drinking water systems through corrosion control requirements (U.S. Environmental Protection Agency, 2008). This usually entails the addition of a corrosion inhibitor, such as orthophosphate, in the water. Violations continue to occur across the United States due to the regulation’s weak implementation and enforcement, including the failure to properly test water quality, failure to report contamination, and failure to treat the water (Olson & Pullen Fedinick, 2016). In the case of Flint, officials switched water sources without implementing measures to protect residents from more corrosive water, causing a city-wide drinking water crisis.
A comprehensive national inventory of lead service lines does not exist in the United States, but estimates range from 6 to 10 million lead service lines providing water to 15 to 22 million Americans (Olson & Pullen Fedinick, 2016). The geographic scope is enormous, and the problem is complicated by the variability of lead levels in tap water, even within the same water system. These conditions pose a significant challenge in identifying sites of contamination and enforcing the Lead and Copper Rule.
The current score for lead exposure has slightly improved compared to the baseline score, indicating that countries have managed to reduce lead poisoning despite a global increase in lead production (see Table 7–2).
|Note: Metrics are in units of age-standardized Disability Adjusted-Life Years lost due to lead exposure. Current refers to the most recently available data from 2016, while Baseline refers to historic data from 2005.|
Global consumption of lead is increasing, driven mainly by the growing demand for lead batteries used in cars. Much of this new demand is in countries experiencing industrialization and urbanization (Landrigan et al., 2017, p. 16). At the same time, the tightening of regulations regarding lead in petrol, paint, and plumbing have resulted in substantial reductions in lead exposure. Most notable is the phase-out of leaded gasoline in more than 175 countries (2017, p. 17). Although lead exposure has decreased, it remains a problem, especially for children in low- and middle-income countries (Attina & Trasande, 2013). Global trends reveal specific vulnerabilities, and children in particular continue to be at heightened risk of exposure from lead-based paint and lead pipes in drinking water systems (2013). Meanwhile, the informal recycling of lead-acid batteries continues with limited oversight and is a major cause of acute lead toxicity for both workers and nearby communities (Landrigan et al., 2017, p. 17).
Leaders & Laggards
Proper management of lead pollution can significantly reduce the risk of widespread lead poisoning. Leaders such as Finland, Germany, Japan, and Sweden have among the lowest levels of lead exposure and are nearly free from the associated health risks – see Table 7–3. This success can be attributed to the phase-out of leaded gasoline in the 1970s and stringent regulatory and public health monitoring mechanisms (Yoshinaga, 2012). In Japan, policies for waste incineration facilities in the late 1990s further decreased atmospheric lead concentration (2012). In the European Union and most other high-income countries, regulations ban the residential use of lead paint (Gottesfeld, 2015).
We find that low- and middle-income countries struggle with lead exposure due to weak or nonexistent chemical safety regulations. Based on WHO’s Global Health Observatory data, only 34% of countries have legally binding controls on the production, import, sale and use of lead paints (World Health Organization, 2017d). Polluting industrial activities like non-regulated lead-acid battery recycling, metal mining, and fossil fuel production, tend to concentrate in developing countries where existing regulatory oversight may be insufficient. A 2016 report – published by the international nonprofit Pure Earth and the Swiss-based foundation Green Cross Switzerland – identified the recycling of used lead-acid car batteries as the number one source of chemical pollution in low- and middle-income countries. Such recycling occurs in nearly every city in the developing world (Pure Earth & Green Cross Switzerland, 2016). Southeast Asia, Africa, and Central and South America are hotspots for lead-acid battery recycling. People employed in lead-acid battery recycling are almost always poor. These people are generally unawareness of the hazards, or powerless to demand protections from lead exposure (Pure Earth & Green Cross Switzerland, 2016).
Countries listed as laggards of lead exposure do not have routine screening processes, detailed investigation into risks, or prevention strategies in response to widespread lead poisoning (Landrigan et al., 2017, p. 27). For example, children in Haiti have elevated blood lead concentrations from exposure to discarded batteries, and lead in drinking water is a pervasive challenge in Pakistan (Carpenter et al., 2016). In a World Bank study of Pakistan’s most populous city of Karachi, 89% of sampled water sources exceeded the WHO’s recommended lead concentration limit of 10 micrograms per liter (µg/L) (Sanchez-Triana, 2016).
To minimize the risk of lead exposure worldwide, countries must make a concerted global effort to establish and enforce policies to eliminate irreversible and costly health impacts. Higher income countries have already enacted effective, scientifically-backed regulations, such as the European Union’s Registration, Evaluation, Authorisation and Restriction of Chemicals. Similar laws can be adapted by countries lacking adequate surveillance of pollution risks. Balancing economic development with pollution control and prevention will be key to ensuring the long-term safety of public health and the environment.
Attina, T., & Trasande, L. (2013). Economic Costs of Childhood Lead Exposure in Low-and Middle-Income Countries. Environ Health Perspective, 121(9). Retrieved from http://dx.doi.org/10.1289/ehp.1206424
Carpenter, C., Potts, B., von Oettingen, J., Bonnell, R., Sainvil, M., Lorgeat, V., … Palfrey, J. (2016). High rates of raised blood lead concentrations in Haitian infants and children. The Lancet. Retrieved from http://www.thelancet.com/pdfs/journals/langlo/PIIS2214-109X(16)30027-4.pdf
Codex Alimentarius Commission. (2016). General Standard for Contaminants and Toxins in Food and Feed CODEX STAN 193-1995. Food and Agriculture organization, World Health Organization. Retrieved from http://www.fao.org/fao-who-codexalimentarius/sh-proxy/en/?lnk=1&url=http...
Crawford, A. (2015). The Mining Policy Framework: Assessing the implementation readiness of member states of the Intergovernmental Forum on Mining, Minerals, Metals and Sustainable Development (p. 10). International Institute for Sustainable Development. Retrieved from https://www.iisd.org/sites/default/files/publications/mining-policy-fram...
EFSA Panel on Contaminants in the Food Chain. (2010). Scientific Opinion on Lead in Food. EFSA Journal, 8(4). https://doi.org/10.2903/j.efsa.2010.1570
Environmental Protection Agency. (2017, May 26). Lead. Retrieved from https://www.epa.gov/lead/learn-about-lead#found
European Chemicals Agency. (n.d.). Understanding REACH. Retrieved December 3, 2017, from https://echa.europa.eu/regulations/reach/understanding-reach
Forouzanfar, M. H., Afshin, A., Alexander, L. T., Anderson, H. R., Bhutta, Z. A., Biryukov, S., … Murray, C. J. L. (2016). Supplementary Appendix: Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. The Lancet, 388(10053), 70–72. https://doi.org/10.1016/S0140-6736(16)31679-8
Gottesfeld, P. (2015). Time to Ban Lead in Industrial Paints and Coatings. Frontiers in Public Health, 3, 144. https://doi.org/10.3389/fpubh.2015.00144
Haefliger, P. (2011). Brief guide to analytical methods for measuring lead in blood (p. 14). Inter-Organization Programme for the Sound Management of Chemicals. Retrieved from http://www.who.int/ipcs/assessment/public_health/lead_blood.pdf
International Labour Organization. (2009a, July 23). International Programme on Chemical Safety (IPCS). Retrieved from http://www.ilo.org/safework/info/WCMS_111391/lang--en/index.htm
International Labour Organization. (2009b, July 23). The Inter-Organization Programme for the Sound Management of Chemicals (IOMC) [Organizational description]. Retrieved December 28, 2017, from http://www.ilo.org/safework/areasofwork/chemical-safety-and-the-environm...
Järup, L. (2003). Hazards of heavy metal contamination. British Medical Bulletin, 68(1), 167–182. https://doi.org/10.1093/bmb/ldg032
Landrigan, P. J., Fuller, R., Acosta, N. J. R., Adeyi, O., Arnold, R., Basu, N. (Nil), … Zhong, M. (2017). The Lancet Commission on pollution and health. The Lancet. https://doi.org/10.1016/S0140-6736(17)32345-0
Liu, D., Liu, X., Chen, Z., Xu, H., & Ding, X. (2010). Bioaccumulation of Lead and the Effects of Lead on Catalase Activity, Glutathione Levels, and Chlorophyll Content in the Leaves of Wheat. Communications in Soil Science and Plant Analysis, 41(8), 935–944. https://doi.org/10.1080/00103621003646022
Liu, G., Yu, Y., Hou, J., Xue, W., Liu, X., Liu, Y., … Liu, Z. (2014). An ecological risk assessment of heavy metal pollution of the agricultural ecosystem near a lead-acid battery factory. Ecological Indicators, 47(Supplement C), 210–218. https://doi.org/10.1016/j.ecolind.2014.04.040
Mamtani, R., Stern, P., Dawood, I., & Cheema, S. (2011). Metals and Disease: A Global Primary Health Care Perspective. Journal of Toxicology, 2011. https://doi.org/10.1155/2011/319136
Meyer, P. A., Brown, M. J., & Falk, H. (2008). Global approach to reducing lead exposure and poisoning. Proceedings of the 5th International Conference on Environmental Mutagens in Human Populations (ICEMHP), 659(1), 166–175. https://doi.org/10.1016/j.mrrev.2008.03.003
Olson, E., & Pullen Fedinick, K. (2016). What’s in Your Water? Flint and Beyond. Natural Resources Defense Council. Retrieved from https://www.nrdc.org/sites/default/files/whats-in-your-water-flint-beyon...
Payne, M., Egden, L., Behinaein, S., Chettle, D., McNeill, F., & Webber, C. (2010). Bone lead measurement. Canadian Family Physician, 56(11), 1110–1111.
Pure Earth, & Green Cross Switzerland. (2016). The World’s Worst Pollution Problems 2016: The Toxics Beneath Our Feet (pp. 1–53). New York, NY. Retrieved from http://www.worstpolluted.org/
Sanchez-Triana, E. (2016, February 17). Lead pollution robs children of their futures. Retrieved December 29, 2017, from https://blogs.worldbank.org/voices/lead-pollution-robs-children-their-fu...
Singh, R., Gautam, N., Mishra, A., & Gupta, R. (2011). Heavy metals and living systems: An overview. Indian Journal of Pharmacology, 43(3), 246–253. https://doi.org/10.4103/0253-7613.81505
Tchounwou, P. B., Yedjou, C. G., Patlolla, A. K., & Sutton, D. J. (2012). Heavy Metals Toxicity and the Environment. EXS, 101, 133–164. https://doi.org/10.1007/978-3-7643-8340-4_6
Thomas Jefferson National Accelerator Facility. (n.d.). It’s Elemental - The Element Lead. Retrieved January 18, 2018, from https://education.jlab.org/itselemental/ele082.html
UNEP-CEP. (2008). Heavy Metals. Retrieved from http://www.cep.unep.org/publications-and-resources/marine-and-coastal-is...
United Nations Environment Programme. (2017a). Minamata Convention on Mercury. Retrieved November 26, 2017, from http://www.mercuryconvention.org/Convention/tabid/3426/language/en-US/De...
United Nations Environment Programme. (2017b). UN Environment 2016 Annual Report. Retrieved from http://web.unep.org/annualreport/2016/index.php?page=7&lang=en
United Nations Environment Programme. (n.d.). SAICM Overview. Retrieved November 26, 2017, from http://www.saicm.org/About/SAICMOverview
U.S. Environmental Protection Agency. (2008). Lead and Copper Rule: A Quick Reference Guide. Retrieved from https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=60001N8P.txt
Wagner, L. (2017, October 5). Minamata COP1 Decides on Compliance Committee, Defers on Key Institutional Arrangements. Retrieved from http://sdg.iisd.org/news/minamata-cop1-decides-on-compliance-committee-d...
World Health Organization. (2010a). Childhood Lead Poisoning (pp. 1–72). Retrieved from http://www.who.int/ceh/publications/leadguidance.pdf
World Health Organization. (2010b). Preventing Disease through Healthy Environments: Exposure to Lead: A Major Public Health Concern. Retrieved from http://www.who.int/ipcs/features/lead..pdf
World Health Organization. (2011). Training Package for the Health Sector: Adverse Health Effects of Heavy Metals in Children. World Health Organization. Retrieved from http://www.who.int/ceh/capacity/heavy_metals.pdf
World Health Organization. (2017a). Recycling used lead-acid batteries: Brief information for the health sector (p. 47). Retrieved from http://www.who.int/ipcs/publications/ulab/en/
World Health Organization. (2017b, August). Fact sheet: Lead poisoning and health. Retrieved December 10, 2017, from http://www.who.int/mediacentre/factsheets/fs379/en/
World Health Organization. (2017c, October). International lead poisoning prevention week of action. Retrieved November 26, 2017, from http://www.who.int/ipcs/lead_campaign/objectives/en/
World Health Organization. (2017d, October 20). Global Health Observatory (GHO) Data. Retrieved January 15, 2018, from http://www.who.int/gho/phe/chemical_safety/lead_paint_regulations/en/
World Health Organization. (n.d.). Global Alliance to Eliminate Lead Paint. Retrieved November 26, 2017, from http://www.who.int/ipcs/assessment/public_health/gaelp/en/
Yoshinaga, J. (2012). Lead in the Japanese living environment. Environmental Health and Preventive Medicine, 17(6), 433–443. https://doi.org/10.1007/s12199-012-0280-z