Correction: The Minderoo-Monaco Commission on Plastics and Human Health

[This corrects the article DOI: 10.5334/aogh.4056.].

The Minderoo-Monaco Commission on Plastics and Human Health

Background

Plastics have conveyed great benefits to humanity and made possible some of the most significant advances of modern civilization in fields as diverse as medicine, electronics, aerospace, construction, food packaging, and sports. It is now clear, however, that plastics are also responsible for significant harms to human health, the economy, and the earth's environment. These harms occur at every stage of the plastic life cycle, from extraction of the coal, oil, and gas that are its main feedstocks through to ultimate disposal into the environment. The extent of these harms not been systematically assessed, their magnitude not fully quantified, and their economic costs not comprehensively counted.

Goals

The goals of this Minderoo-Monaco Commission on Plastics and Human Health are to comprehensively examine plastics' impacts across their life cycle on: (1) human health and well-being; (2) the global environment, especially the ocean; (3) the economy; and (4) vulnerable populations-the poor, minorities, and the world's children. On the basis of this examination, the Commission offers science-based recommendations designed to support development of a Global Plastics Treaty, protect human health, and save lives.

Report Structure

This Commission report contains seven Sections. Following an Introduction, Section 2 presents a narrative review of the processes involved in plastic production, use, and disposal and notes the hazards to human health and the environment associated with each of these stages. Section 3 describes plastics' impacts on the ocean and notes the potential for plastic in the ocean to enter the marine food web and result in human exposure. Section 4 details plastics' impacts on human health. Section 5 presents a first-order estimate of plastics' health-related economic costs. Section 6 examines the intersection between plastic, social inequity, and environmental injustice. Section 7 presents the Commission's findings and recommendations.

Plastics

Plastics are complex, highly heterogeneous, synthetic chemical materials. Over 98% of plastics are produced from fossil carbon- coal, oil and gas. Plastics are comprised of a carbon-based polymer backbone and thousands of additional chemicals that are incorporated into polymers to convey specific properties such as color, flexibility, stability, water repellence, flame retardation, and ultraviolet resistance. Many of these added chemicals are highly toxic. They include carcinogens, neurotoxicants and endocrine disruptors such as phthalates, bisphenols, per- and poly-fluoroalkyl substances (PFAS), brominated flame retardants, and organophosphate flame retardants. They are integral components of plastic and are responsible for many of plastics' harms to human health and the environment.Global plastic production has increased almost exponentially since World War II, and in this time more than 8,300 megatons (Mt) of plastic have been manufactured. Annual production volume has grown from under 2 Mt in 1950 to 460 Mt in 2019, a 230-fold increase, and is on track to triple by 2060. More than half of all plastic ever made has been produced since 2002. Single-use plastics account for 35-40% of current plastic production and represent the most rapidly growing segment of plastic manufacture.Explosive recent growth in plastics production reflects a deliberate pivot by the integrated multinational fossil-carbon corporations that produce coal, oil and gas and that also manufacture plastics. These corporations are reducing their production of fossil fuels and increasing plastics manufacture. The two principal factors responsible for this pivot are decreasing global demand for carbon-based fuels due to increases in 'green' energy, and massive expansion of oil and gas production due to fracking.Plastic manufacture is energy-intensive and contributes significantly to climate change. At present, plastic production is responsible for an estimated 3.7% of global greenhouse gas emissions, more than the contribution of Brazil. This fraction is projected to increase to 4.5% by 2060 if current trends continue unchecked.

Plastic Life Cycle

The plastic life cycle has three phases: production, use, and disposal. In production, carbon feedstocks-coal, gas, and oil-are transformed through energy-intensive, catalytic processes into a vast array of products. Plastic use occurs in every aspect of modern life and results in widespread human exposure to the chemicals contained in plastic. Single-use plastics constitute the largest portion of current use, followed by synthetic fibers and construction.Plastic disposal is highly inefficient, with recovery and recycling rates below 10% globally. The result is that an estimated 22 Mt of plastic waste enters the environment each year, much of it single-use plastic and are added to the more than 6 gigatons of plastic waste that have accumulated since 1950. Strategies for disposal of plastic waste include controlled and uncontrolled landfilling, open burning, thermal conversion, and export. Vast quantities of plastic waste are exported each year from high-income to low-income countries, where it accumulates in landfills, pollutes air and water, degrades vital ecosystems, befouls beaches and estuaries, and harms human health-environmental injustice on a global scale. Plastic-laden e-waste is particularly problematic.

Environmental Findings

Plastics and plastic-associated chemicals are responsible for widespread pollution. They contaminate aquatic (marine and freshwater), terrestrial, and atmospheric environments globally. The ocean is the ultimate destination for much plastic, and plastics are found throughout the ocean, including coastal regions, the sea surface, the deep sea, and polar sea ice. Many plastics appear to resist breakdown in the ocean and could persist in the global environment for decades. Macro- and micro-plastic particles have been identified in hundreds of marine species in all major taxa, including species consumed by humans. Trophic transfer of microplastic particles and the chemicals within them has been demonstrated. Although microplastic particles themselves (>10 µm) appear not to undergo biomagnification, hydrophobic plastic-associated chemicals bioaccumulate in marine animals and biomagnify in marine food webs. The amounts and fates of smaller microplastic and nanoplastic particles (MNPs <10 µm) in aquatic environments are poorly understood, but the potential for harm is worrying given their mobility in biological systems. Adverse environmental impacts of plastic pollution occur at multiple levels from molecular and biochemical to population and ecosystem. MNP contamination of seafood results in direct, though not well quantified, human exposure to plastics and plastic-associated chemicals. Marine plastic pollution endangers the ocean ecosystems upon which all humanity depends for food, oxygen, livelihood, and well-being.

Human Health Findings

Coal miners, oil workers and gas field workers who extract fossil carbon feedstocks for plastic production suffer increased mortality from traumatic injury, coal workers' pneumoconiosis, silicosis, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer. Plastic production workers are at increased risk of leukemia, lymphoma, hepatic angiosarcoma, brain cancer, breast cancer, mesothelioma, neurotoxic injury, and decreased fertility. Workers producing plastic textiles die of bladder cancer, lung cancer, mesothelioma, and interstitial lung disease at increased rates. Plastic recycling workers have increased rates of cardiovascular disease, toxic metal poisoning, neuropathy, and lung cancer. Residents of "fenceline" communities adjacent to plastic production and waste disposal sites experience increased risks of premature birth, low birth weight, asthma, childhood leukemia, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer.During use and also in disposal, plastics release toxic chemicals including additives and residual monomers into the environment and into people. National biomonitoring surveys in the USA document population-wide exposures to these chemicals. Plastic additives disrupt endocrine function and increase risk for premature births, neurodevelopmental disorders, male reproductive birth defects, infertility, obesity, cardiovascular disease, renal disease, and cancers. Chemical-laden MNPs formed through the environmental degradation of plastic waste can enter living organisms, including humans. Emerging, albeit still incomplete evidence indicates that MNPs may cause toxicity due to their physical and toxicological effects as well as by acting as vectors that transport toxic chemicals and bacterial pathogens into tissues and cells.Infants in the womb and young children are two populations at particularly high risk of plastic-related health effects. Because of the exquisite sensitivity of early development to hazardous chemicals and children's unique patterns of exposure, plastic-associated exposures are linked to increased risks of prematurity, stillbirth, low birth weight, birth defects of the reproductive organs, neurodevelopmental impairment, impaired lung growth, and childhood cancer. Early-life exposures to plastic-associated chemicals also increase the risk of multiple non-communicable diseases later in life.

Economic Findings

Plastic's harms to human health result in significant economic costs. We estimate that in 2015 the health-related costs of plastic production exceeded $250 billion (2015 Int$) globally, and that in the USA alone the health costs of disease and disability caused by the plastic-associated chemicals PBDE, BPA and DEHP exceeded $920 billion (2015 Int$). Plastic production results in greenhouse gas (GHG) emissions equivalent to 1.96 gigatons of carbon dioxide (CO2e) annually. Using the US Environmental Protection Agency's (EPA) social cost of carbon metric, we estimate the annual costs of these GHG emissions to be $341 billion (2015 Int$).These costs, large as they are, almost certainly underestimate the full economic losses resulting from plastics' negative impacts on human health and the global environment. All of plastics' economic costs-and also its social costs-are externalized by the petrochemical and plastic manufacturing industry and are borne by citizens, taxpayers, and governments in countries around the world without compensation.

Social Justice Findings

The adverse effects of plastics and plastic pollution on human health, the economy and the environment are not evenly distributed. They disproportionately affect poor, disempowered, and marginalized populations such as workers, racial and ethnic minorities, "fenceline" communities, Indigenous groups, women, and children, all of whom had little to do with creating the current plastics crisis and lack the political influence or the resources to address it. Plastics' harmful impacts across its life cycle are most keenly felt in the Global South, in small island states, and in disenfranchised areas in the Global North. Social and environmental justice (SEJ) principles require reversal of these inequitable burdens to ensure that no group bears a disproportionate share of plastics' negative impacts and that those who benefit economically from plastic bear their fair share of its currently externalized costs.

Conclusions

It is now clear that current patterns of plastic production, use, and disposal are not sustainable and are responsible for significant harms to human health, the environment, and the economy as well as for deep societal injustices.The main driver of these worsening harms is an almost exponential and still accelerating increase in global plastic production. Plastics' harms are further magnified by low rates of recovery and recycling and by the long persistence of plastic waste in the environment.The thousands of chemicals in plastics-monomers, additives, processing agents, and non-intentionally added substances-include amongst their number known human carcinogens, endocrine disruptors, neurotoxicants, and persistent organic pollutants. These chemicals are responsible for many of plastics' known harms to human and planetary health. The chemicals leach out of plastics, enter the environment, cause pollution, and result in human exposure and disease. All efforts to reduce plastics' hazards must address the hazards of plastic-associated chemicals.

Recommendations

To protect human and planetary health, especially the health of vulnerable and at-risk populations, and put the world on track to end plastic pollution by 2040, this Commission supports urgent adoption by the world's nations of a strong and comprehensive Global Plastics Treaty in accord with the mandate set forth in the March 2022 resolution of the United Nations Environment Assembly (UNEA).International measures such as a Global Plastics Treaty are needed to curb plastic production and pollution, because the harms to human health and the environment caused by plastics, plastic-associated chemicals and plastic waste transcend national boundaries, are planetary in their scale, and have disproportionate impacts on the health and well-being of people in the world's poorest nations. Effective implementation of the Global Plastics Treaty will require that international action be coordinated and complemented by interventions at the national, regional, and local levels.This Commission urges that a cap on global plastic production with targets, timetables, and national contributions be a central provision of the Global Plastics Treaty. We recommend inclusion of the following additional provisions:The Treaty needs to extend beyond microplastics and marine litter to include all of the many thousands of chemicals incorporated into plastics.The Treaty needs to include a provision banning or severely restricting manufacture and use of unnecessary, avoidable, and problematic plastic items, especially single-use items such as manufactured plastic microbeads.The Treaty needs to include requirements on extended producer responsibility (EPR) that make fossil carbon producers, plastic producers, and the manufacturers of plastic products legally and financially responsible for the safety and end-of-life management of all the materials they produce and sell.The Treaty needs to mandate reductions in the chemical complexity of plastic products; health-protective standards for plastics and plastic additives; a requirement for use of sustainable non-toxic materials; full disclosure of all components; and traceability of components. International cooperation will be essential to implementing and enforcing these standards.The Treaty needs to include SEJ remedies at each stage of the plastic life cycle designed to fill gaps in community knowledge and advance both distributional and procedural equity.This Commission encourages inclusion in the Global Plastic Treaty of a provision calling for exploration of listing at least some plastic polymers as persistent organic pollutants (POPs) under the Stockholm Convention.This Commission encourages a strong interface between the Global Plastics Treaty and the Basel and London Conventions to enhance management of hazardous plastic waste and slow current massive exports of plastic waste into the world's least-developed countries.This Commission recommends the creation of a Permanent Science Policy Advisory Body to guide the Treaty's implementation. The main priorities of this Body would be to guide Member States and other stakeholders in evaluating which solutions are most effective in reducing plastic consumption, enhancing plastic waste recovery and recycling, and curbing the generation of plastic waste. This Body could also assess trade-offs among these solutions and evaluate safer alternatives to current plastics. It could monitor the transnational export of plastic waste. It could coordinate robust oceanic-, land-, and air-based MNP monitoring programs.This Commission recommends urgent investment by national governments in research into solutions to the global plastic crisis. This research will need to determine which solutions are most effective and cost-effective in the context of particular countries and assess the risks and benefits of proposed solutions. Oceanographic and environmental research is needed to better measure concentrations and impacts of plastics <10 µm and understand their distribution and fate in the global environment. Biomedical research is needed to elucidate the human health impacts of plastics, especially MNPs.

Summary

This Commission finds that plastics are both a boon to humanity and a stealth threat to human and planetary health. Plastics convey enormous benefits, but current linear patterns of plastic production, use, and disposal that pay little attention to sustainable design or safe materials and a near absence of recovery, reuse, and recycling are responsible for grave harms to health, widespread environmental damage, great economic costs, and deep societal injustices. These harms are rapidly worsening.While there remain gaps in knowledge about plastics' harms and uncertainties about their full magnitude, the evidence available today demonstrates unequivocally that these impacts are great and that they will increase in severity in the absence of urgent and effective intervention at global scale. Manufacture and use of essential plastics may continue. However, reckless increases in plastic production, and especially increases in the manufacture of an ever-increasing array of unnecessary single-use plastic products, need to be curbed.Global intervention against the plastic crisis is needed now because the costs of failure to act will be immense.

How does formal and informal industry contribute to lead exposure? A narrative review from Vietnam, Uruguay, and Malaysia

INTRODUCTION

Lead industries are one of the major sources of environmental pollution and can affect human through different activities, including industrial processes, metal plating, mining, battery recycling, etc. Although different studies have documented the various sources of lead exposure, studies highlighting different types of industries as sources of environmental contamination are limited. Therefore, this narrative review aims to focus mainly on lead industries as significant sources of environmental and human contamination.

CONTENT

Based on the keywords searched in bibliographic databases we found 44 relevant articles that provided information on lead present in soil, water, and blood or all components among participants living near high-risk areas. We presented three case scenarios to highlight how lead industries have affected the health of citizens in Vietnam, Uruguay, and Malaysia.

SUMMARY AND OUTLOOK

Factories conducting mining, e-waste processing, used lead-acid battery recycling, electronic repair, and toxic waste sites were the primary industries for lead exposure. Our study has shown lead exposure due to industrial activities in Vietnam, Uruguay, Malaysia and calls for attention to the gaps in strategic and epidemiologic efforts to understand sources of environmental exposure to lead fully. Developing strategies and guidelines to regulate industrial activities, finding alternatives to reduce lead toxicity and exposure, and empowering the public through various community awareness programs can play a crucial role in controlling exposure to lead.

Human Health and Ocean Pollution

Background

Pollution - unwanted waste released to air, water, and land by human activity - is the largest environmental cause of disease in the world today. It is responsible for an estimated nine million premature deaths per year, enormous economic losses, erosion of human capital, and degradation of ecosystems. Ocean pollution is an important, but insufficiently recognized and inadequately controlled component of global pollution. It poses serious threats to human health and well-being. The nature and magnitude of these impacts are only beginning to be understood.

Goals

(1) Broadly examine the known and potential impacts of ocean pollution on human health. (2) Inform policy makers, government leaders, international organizations, civil society, and the global public of these threats. (3) Propose priorities for interventions to control and prevent pollution of the seas and safeguard human health.

Methods

Topic-focused reviews that examine the effects of ocean pollution on human health, identify gaps in knowledge, project future trends, and offer evidence-based guidance for effective intervention.

Environmental Findings

Pollution of the oceans is widespread, worsening, and in most countries poorly controlled. It is a complex mixture of toxic metals, plastics, manufactured chemicals, petroleum, urban and industrial wastes, pesticides, fertilizers, pharmaceutical chemicals, agricultural runoff, and sewage. More than 80% arises from land-based sources. It reaches the oceans through rivers, runoff, atmospheric deposition and direct discharges. It is often heaviest near the coasts and most highly concentrated along the coasts of low- and middle-income countries. Plastic is a rapidly increasing and highly visible component of ocean pollution, and an estimated 10 million metric tons of plastic waste enter the seas each year. Mercury is the metal pollutant of greatest concern in the oceans; it is released from two main sources - coal combustion and small-scale gold mining. Global spread of industrialized agriculture with increasing use of chemical fertilizer leads to extension of Harmful Algal Blooms (HABs) to previously unaffected regions. Chemical pollutants are ubiquitous and contaminate seas and marine organisms from the high Arctic to the abyssal depths.

Ecosystem Findings

Ocean pollution has multiple negative impacts on marine ecosystems, and these impacts are exacerbated by global climate change. Petroleum-based pollutants reduce photosynthesis in marine microorganisms that generate oxygen. Increasing absorption of carbon dioxide into the seas causes ocean acidification, which destroys coral reefs, impairs shellfish development, dissolves calcium-containing microorganisms at the base of the marine food web, and increases the toxicity of some pollutants. Plastic pollution threatens marine mammals, fish, and seabirds and accumulates in large mid-ocean gyres. It breaks down into microplastic and nanoplastic particles containing multiple manufactured chemicals that can enter the tissues of marine organisms, including species consumed by humans. Industrial releases, runoff, and sewage increase frequency and severity of HABs, bacterial pollution, and anti-microbial resistance. Pollution and sea surface warming are triggering poleward migration of dangerous pathogens such as the Vibrio species. Industrial discharges, pharmaceutical wastes, pesticides, and sewage contribute to global declines in fish stocks.

Human Health Findings

Methylmercury and PCBs are the ocean pollutants whose human health effects are best understood. Exposures of infants in utero to these pollutants through maternal consumption of contaminated seafood can damage developing brains, reduce IQ and increase children's risks for autism, ADHD and learning disorders. Adult exposures to methylmercury increase risks for cardiovascular disease and dementia. Manufactured chemicals - phthalates, bisphenol A, flame retardants, and perfluorinated chemicals, many of them released into the seas from plastic waste - can disrupt endocrine signaling, reduce male fertility, damage the nervous system, and increase risk of cancer. HABs produce potent toxins that accumulate in fish and shellfish. When ingested, these toxins can cause severe neurological impairment and rapid death. HAB toxins can also become airborne and cause respiratory disease. Pathogenic marine bacteria cause gastrointestinal diseases and deep wound infections. With climate change and increasing pollution, risk is high that Vibrio infections, including cholera, will increase in frequency and extend to new areas. All of the health impacts of ocean pollution fall disproportionately on vulnerable populations in the Global South - environmental injustice on a planetary scale.

Conclusions

Ocean pollution is a global problem. It arises from multiple sources and crosses national boundaries. It is the consequence of reckless, shortsighted, and unsustainable exploitation of the earth's resources. It endangers marine ecosystems. It impedes the production of atmospheric oxygen. Its threats to human health are great and growing, but still incompletely understood. Its economic costs are only beginning to be counted.Ocean pollution can be prevented. Like all forms of pollution, ocean pollution can be controlled by deploying data-driven strategies based on law, policy, technology, and enforcement that target priority pollution sources. Many countries have used these tools to control air and water pollution and are now applying them to ocean pollution. Successes achieved to date demonstrate that broader control is feasible. Heavily polluted harbors have been cleaned, estuaries rejuvenated, and coral reefs restored.Prevention of ocean pollution creates many benefits. It boosts economies, increases tourism, helps restore fisheries, and improves human health and well-being. It advances the Sustainable Development Goals (SDG). These benefits will last for centuries.

Recommendations

World leaders who recognize the gravity of ocean pollution, acknowledge its growing dangers, engage civil society and the global public, and take bold, evidence-based action to stop pollution at source will be critical to preventing ocean pollution and safeguarding human health.Prevention of pollution from land-based sources is key. Eliminating coal combustion and banning all uses of mercury will reduce mercury pollution. Bans on single-use plastic and better management of plastic waste reduce plastic pollution. Bans on persistent organic pollutants (POPs) have reduced pollution by PCBs and DDT. Control of industrial discharges, treatment of sewage, and reduced applications of fertilizers have mitigated coastal pollution and are reducing frequency of HABs. National, regional and international marine pollution control programs that are adequately funded and backed by strong enforcement have been shown to be effective. Robust monitoring is essential to track progress.Further interventions that hold great promise include wide-scale transition to renewable fuels; transition to a circular economy that creates little waste and focuses on equity rather than on endless growth; embracing the principles of green chemistry; and building scientific capacity in all countries.Designation of Marine Protected Areas (MPAs) will safeguard critical ecosystems, protect vulnerable fish stocks, and enhance human health and well-being. Creation of MPAs is an important manifestation of national and international commitment to protecting the health of the seas.

Impact of pesticide exposure in childhood

Pesticides represent a wide variety of chemicals presented as different formulations and concentrations and used in different settings: agriculture, animal sanitary bath, domestic use, and vector control. Lack of awareness, poor agricultural practices, and inappropriate disposal of containers will increase the exposure and risk of health effects during childhood. The concern about children's exposure to pesticides is based on their toxic properties and the special vulnerability to the exposure, which may occur in different stages, from the prenatal period to infancy. Pesticide related diseases may manifest during the infancy, adolescence, or adulthood. Children may be exposed by multiple routes of exposure, in different scenarios. In domestic settings, insecticides and rodenticides are usually stored within the reach of children, or may be transferred to non-original containers, leading to acute non intentional ingestion. Exploratory behavior increases the risk for exposure to pesticides present on the ground. Gardens and playgrounds may have pesticides residues. Children may be in contact with domestic animals that have been treated with pesticides. In rural settings, children can be exposed to pesticide residues in areas where they have been applied, or by contamination of work equipment and parents clothing. Families dedicated to rural activity have higher levels of exposure, through ingesting contaminated fruits, vegetables, milk, eggs, and water. Several studies confirmed pesticide exposure in children by biomonitoring. Higher levels of organophosphate metabolites have been reported in children compared to adult populations. Toxic effects of pesticides depend on their intrinsic toxic properties as well as on the dose, duration, and life period of exposure. Acute poisonings are related to high doses exposure, while chronic, subtle and delayed effects are often related to low levels/doses exposure. Epidemiologic, animal, and clinical studies suggest an association between chronic, low-level exposures and alterations in growth and development (particularly impaired neurobehavioral development), cancer and increased susceptibility to infections. New research presents evidence that some pesticides are a risk factor of a wide range of acute and chronic diseases. Better practices and public health policies are needed to prevent and protect children from pesticides exposure.

Strategic methodology to set priorities for sustainable hydropower development in a biodiversity hotspot

Massive exploitation of freshwater systems for hydropower generation in developing countries is challenging sustainability due to cumulative environmental impacts in regions with high endemism. Habitat fragmentation is recognized as a major impact on river ecosystems. The nature and magnitude of connectivity loss depend on characteristics of the hydropower projects, and of the threatened fish communities. In areas where appropriate mitigation technology is lacking, there is a need to identify the fish species that are most at risk to better concentrate efforts. This paper aimed to set conservation priorities for sustainable hydropower development by analyzing native fish species and project characteristics. The Chilean ichthyogeographic province, an ecoregion with high endemism and massive hydropower projects development, has been considered as a case study. By using overlapping information on the characteristics of 1124 hydropower projects and distribution of native fish species, we identified three project categories of projects based on their need for mitigation. These were projects where mitigation was considered: a) not required (15%), b) required and feasible (35%), and c) required but challenging (50%). Projects where mitigation was not required were located at sites where native fish were absent and/or where water intakes allowed fish to pass. Interestingly, projects where mitigation was feasible were inhabited by a species assemblage that comprised the genus Trichomycterus, Diplomystes and Percilia, and the species Ch. pisciculus and B. maldonadoi. This finding emphasizes the need to develop a multispecific fishway that can accommodate this group. Projects where mitigation would be difficult to achieve were located at sites with a variety of different assemblages, thus making a standard fish pass solution challenging and site-specific. This study advances understanding for the need to develop mitigation strategies and technologies in ecoregions of high endemism threatened by hydropower and to prioritize the construction of planned projects.

E-Waste Informal Recycling: An Emerging Source of Lead Exposure in South America

BACKGROUND

Primitive electronic waste (e-waste) recycling creates exposures to several hazardous substances including lead. In Uruguay, primitive recycling procedures are a significant source of lead exposure.

OBJECTIVES

The aim of this study was to examine lead exposure in blood lead levels (BLLs) in low-income children exposed to lead through burning cables.

METHODS

A sample of children and adolescents exposed to lead through burning cable activities were assessed at the Department of Toxicology in Montevideo, Uruguay, between 2010 and 2014. Soil lead levels of residences were taken shortly after their assessment.

FINDINGS

The final sample included 69 children and adolescents (mean age 7.89 years). More than 66% of participants had an additional source of lead exposure-manual gathering of metals-and <5% were exposed to lead through landfills or paint. Average BLLs at first consultation were 9.19 ug/dL and lower at the second measurement (5.86 μg/dL). Data from soil lead levels ranged from 650 to 19,000 mg of lead/kg of soil. The interventions conducted after the assessment included family education in the clinic and at home, indoor and outdoor remediation. We found a decrease in BLLs of 6.96 μg/dL. Older children had lower BLLs (r = -0.24; P = 0.05). Statistical analyses also showed that children living in areas with higher soil lead levels had significantly higher BLLs (r = 0.50; P < 0.01). Additionally, we found greater BLLs from burning cable activities when children had been exposed to lead-based paint (r = 0.23; P < 0.1).

CONCLUSION

Among children exposed to e-waste recycling, the most common additional source of lead exposure was the manual gathering of metals. The average BLL among children and adolescents in this study is higher than the BLLs currently suggested in medical intervention. Future research should focus on exploring effective interventions to reduce lead exposure among this vulnerable group.

Children's health in Latin America: the influence of environmental exposures

BACKGROUND

Chronic diseases are increasing among children in Latin America.

OBJECTIVE AND METHODS

To examine environmental risk factors for chronic disease in Latin American children and to develop a strategic initiative for control of these exposures, the World Health Organization (WHO) including the Pan American Health Organization (PAHO), the Collegium Ramazzini, and Latin American scientists reviewed regional and relevant global data.

RESULTS

Industrial development and urbanization are proceeding rapidly in Latin America, and environmental pollution has become widespread. Environmental threats to children's health include traditional hazards such as indoor air pollution and drinking-water contamination; the newer hazards of urban air pollution; toxic chemicals such as lead, asbestos, mercury, arsenic, and pesticides; hazardous and electronic waste; and climate change. The mix of traditional and modern hazards varies greatly across and within countries reflecting industrialization, urbanization, and socioeconomic forces.

CONCLUSIONS

To control environmental threats to children's health in Latin America, WHO, including PAHO, will focus on the most highly prevalent and serious hazards-indoor and outdoor air pollution, water pollution, and toxic chemicals. Strategies for controlling these hazards include developing tracking data on regional trends in children's environmental health (CEH), building a network of Collaborating Centres, promoting biomedical research in CEH, building regional capacity, supporting development of evidence-based prevention policies, studying the economic costs of chronic diseases in children, and developing platforms for dialogue with relevant stakeholders.

[Cocaine base paste: experience from the Montevideo Poison Control Center]

BACKGROUND

In Uruguay, cocaine base paste (CBP, pasta base) is a widely used form of cocaine. The aim of our study is to determine the main clinical characteristics of CBP abusers.

METHODS

Retrospective, single-center study of consultations at the Montevideo Poison Control Center between January 1, 2004 and December 31, 2005.

RESULTS

One hundred and thirteen consultations were included, with an average age of 22 years (+ - 0.5 years) and a female-male sex ratio of 1:4.3. The consultations were related to drug overdose (77%), suicide attempt (16.8%), and wanting to give up CBP use (6.2%). In 48.1% the time elapsed since inhalation of CBP was less than 6 hours. Doses varied between 0.5 gr. and 25 gr. Use of other drugs at the same time, such as alcohol, marijuana or benzodiazepines, was common (51 cases). The symptoms most frequently observed were neuropsychiatric and cardiovascular, followed by respiratory symptoms. In 16.8% of patients, reason for the consultation was intentional acute ingestion of drugs, considered as a suicide attempt, occurring within a few hours of drug consumption.

DISCUSSION

CBP users are mostly young males. Although clinical findings are compatible with those for cocaine abuse, euphoria is a major clinical feature in CBP abusers. The presence of respiratory symptoms reflects the complications associated with the ingestion route. Suicide attempts occurring within a few hours of CBP confirm the high prevalence of suicidal ideation reported by other authors. cocaine base paste, clinical features, suicide attempts.

Priority setting for risk assessment--the benefit of human experience

The chemical risk assessment process plays an essential role in the potential human health risk evaluation. Setting priorities for this purpose is critical for better use of the available human and material resources. It has been generally accepted that all new chemicals require safety evaluation before manufacture and sale. This is a difficult task due to the large number of chemicals directly consumed by man, as well as those that are widely used. At present, more than 50% of chemicals do not have the minimum data requirements for risk assessment. Production and release volumes are well-established prioritization criteria, although volume itself does not directly reflect the likelihood of human exposure. This quantitative approach applied in setting priorities may be influenced by human experience. Human data provided by epidemiological investigations have been accepted as the most credible evidence for human toxicity although analytical studies are expensive and require long-term follow up. Unfortunately, some epidemiological studies continue to have difficulties with exposure documentation, controlling bias and confounding, and are not able to provide predictions of risk until humans are exposed. Clinical toxicology services and Poison Centres around the world accumulate a great amount of toxicological-related information that may contribute to the evidence-based medicine and research and so collaborate with all the risk assessment disciplines. The information obtained from these services and centers has the potential to prioritize existing chemical assessment processes or to influence scheduling of classes of chemicals. Prioritization process may be improved by evaluating Poisons Centres statistics about frequency of cases, severity of effects, detection of unusual circumstances of exposure, as well as vulnerable sub-populations. International efforts for the harmonization of these data offer a useful tool to take advantage of this global information. Case report and case series may give information about the spectrum of human health effects, particularly when frequency is not very high. Improvement in the access to this information could be facilitated by better documentation of cases and targeted follow up. Special attention should be given to strengthen the documentation capabilities of clinical toxicologists, occupational physicians, and forensic toxicologists from developing countries. The benefit of human experience on priority setting for risk assessment purpose depends not only on the quality of information but also on the improvement of understanding between risk assessors and clinical toxicologists or poison center specialists.

New roles for poison control centres in the developing countries

The primary mission of poison control centres has always been an improvement in the poisoned patients' care and poison prevention. The need to reach this mission implies that many functions and roles must be accomplished. Many centres, even in developing countries, are multifunctional and provide a broad toxicological information service. However, the main challenges of poison centres in developing countries are still treatment information, formal training, laboratory services accessibility and availability of antidotes. At the same time poison centres from developing countries need to accomplish their public health mission through strengthening and expansion of some well-defined roles like toxico-surveillance and environmental health monitoring according to the prevailing and future toxicological problems. Poison control centres from developing countries continue to face old challenges but cannot ignore the new ones that appear in the globalised world. Poison centres have a vital role for environmental exposure surveillance systems for sentinel event detection. Poison centres offer real-time and continuous data needed for preparation and response during such events and also offer a means to report health concerns. Centres from South America were involved in some of the most important environmental health problems of the region e.g., lead contamination (children), children 'occupational' poisoning, and flour contamination with fusarium toxins. Furthermore, poison centres can be the markers of risk factors or identifiers of vulnerable population e.g., changes in drugs prescription patterns, unusual patterns of addiction, unexpected product uses, children abuse scenarios or undetected sources of environmental contamination. In an era of evidence-based medicine and research, toxico-vigilance based on the millions of cases registered by poison centres everyday acquires more and more importance. A new approach of the toxico-vigilance and preventive roles of poison information centres lies in their ability to contribute to risk assessment methodologies with their human data. The data routinely collected by poisons centres could contribute to risk assessment documentation and to define priorities for risk assessment of the harmful chemicals. Although there is some scepticism about the value of poison centres data, the shared volume of human data could validate this information. The international effort of the IPCS/INTOX program, on harmonisation of data collection and terminology for comparable recording of observational human data, has been a great advancement towards handling this problem.

Étude comparative de deux protocoles d’électrostimulation du quadriceps après chirurgie du ligament croisé antérieur. Étude de faisabilité

OBJECTIVES

To evaluate the feasibility of a study comparing the effects of two protocols of electrical stimulation of the quadriceps femoris after anterior cruciate ligament surgery.

MATERIAL

Seven sportsmen with a mean age of 26 yrs were randomly grouped in two: a 20 Hz stimulated group (4 patients) and a 80 Hz stimulated group (3 patients). After surgery all patients received electrical stimulation of the quadriceps femoris, five days a week, for 12 weeks, and had a standard program of voluntary contractions. The main outcome assessed before and three months after surgery were: quadriceps and hamstring peak torque at 90, 180 and 240 degrees /second, maximal isometric quadriceps at 75 degrees of flexion and muscle and subcutaneous fat volumes of the thigh using MRI.

RESULTS

After 12 weeks of rehabilitation, the thigh muscle volume deficit of the operated limb was between 3 and 9% in the 20 Hz stimulated group and between 1 and 2% in the 80 Hz stimulated group. Quadriceps peak torque deficit was less than 30% except for two patients in the 20 Hz stimulated group. Maximal isometric quadriceps deficit of the operated limb was higher than 30% except for two patients in the 20 Hz stimulated group.

CONCLUSION

The study showed that comparison of two protocols of electrical stimulation of the quadriceps femoris after anterior cruciate ligament surgery is possible if stimulation period is not more than four weeks.

10CASA EVALUATION OF SEXED AND NON-SEXED FROZEN BULL SEMEN

Flow citometry cell sorting has been proven successfully to separate X and Y sperm; however, the technology is still too stressfull for the viability of the sorted semen. The objective of this study was to evaluate nonsexed and sexed frozen sperm motility characteristics using a CASA technology. Ejaculates from 4 different bulls (3 Holstein and 1 Angus) were collected, and processed as split non-sexed and sexed semen samples using Tris egg yolk extenders. X and Y sperm were separated using a high-speed sorter (SX Moflo). Cryopreservation was done at the same time under appropiate conditions using a programmed cryochamber. Thawing procedure was done at 37°C for 30s and a sample of each straw was placed in the evaluation chamber. The experiment was repeated twice and two chambers with 30 observations each were analyzed each time. Mean and standard deviation of each characteristic were calculated, compared and analyzed statistically. The sperm concentration was determined by means of a burker counting chamber. Sperm quality was determined at 0h after thawing, and later at 1h, 2h and 3h after incubation in a glass tube at 30°C. The following sperm motility parameters were determined with the Hamilton Thorne (HTM-ceros 12.1) on at least 1000 spermatozoa: velocity average path (VAP), velocity straight line (VSL), amplitude lateral head (ALH), beat cross frequency (BCF), straightness (STR), linearity (LIN), and percentage of progressively motile spermatozoa (PMS). Linearity of nonsexed spermatozoa was 53±3.5, 47±0.8, 43±7.8 and 42±4.5 for the 0h and the 3 test incubation times and 49.5±3.7, 51.2±3.7, 43.3±7.8 and 44.5±7.6, respectively, for sexed semen. There were no significant differences (P&gt;0.05) in the progressive velocity, track speed and linearity between sexed and nonsexed semen. The percentage of static cells was 33%, 30%, 47% and 50% for the 0h and the 3 test incubation periods; however, the percentage of static cells for the sexed semen was 53%, 71%, 77% and 82%, respectively. Results from the analysis indicate a significant increase (P&lt;0.01) in the number and the percentage of static cells with time. The lateral amplitude of sperm motility for nonsexed semen was 5.9±0.5, 6.8±0.8, 6.0±0.4 and 5.1±0.7, and for sexed semen 6.6±0.7, 6.8±0.4, 6.4±0.4 and 5.5±1.7, respectively. The percentage of progressively motile sperm was significantly different at 0 time 49.7±4.9 and 23.1±4.9 for nonsexed and sexed semen respectively. After 3 hours of incubation the percentage of progressively motile sperm was 38.7±10.2 and 3.7±3.2 for nonsexed and sexed semen, respectively. In conclusion, sexed frozen semen seems to have characteristics similar to those of normal nonsexed semen. However, a significant decrease in the percentage of progressively motile cells could affect pregnancy rates. More research needs to be done to detect differences between bulls and cryoprotectans.Research supported by Centro Genetico Bovino de EOLIA sa Argentina.

Herbal infusions used for induced abortion

Plants and herbs have been used to induce abortions but there is very little published information describing the commonly used ones. The purpose of this report is to describe the herbal products used to induce abortions, and to enhance awareness and understanding of their toxic effects. A descriptive retrospective survey was conducted on the calls received by the Montevideo Poison Centre between 1986 and 1999 concerning the ingestion of herbal infusions with abortive intent. A total of 86 cases involving 30 different plant species were identified. The species most frequently involved were ruda (Ruta chalepensis/graveolens), cola de quirquincho (Lycopodium saururus), parsley (Petroselinum hortense), and an over-the-counter herbal product named Carachipita. The components of Carachipita are pennyroyal (Mentha pulegium), yerba de la perdiz (Margiricarpus pinnatus), oregano (Origanum vulgare), and guaycuri (Statice brasiliensis). Abortion occurred in 23 cases after the ingestion of parsley, ruda, Carachipita, celery, Cedron, francisco alvarez, floripon, espina colorada. Out of the 23 cases, 15 involved the only the ingestion of plants, 4 cases used injected drugs (presumably hormones), and in 4 cases there was associated self-inflicted instrumental manipulation. Multiple organ system failure occurred in those patients who had ingested ruda (alone or in combination with parsley or fennel), Carachipita, arnica, or bardana. Deaths occurred in one case of Carachipita ingestion and in 4 cases of ruda ingestion (2 cases of ruda alone, 2 cases of ruda with parsley and fennel). Self-inflicted instrumental manipulations were found in 4 of the patients with multiple organ system failure and in one of those who died. The results of this report are not conclusive, but it appears that the ingestion of plants to induce abortion involves the risk of severe morbidity and mortality.

Effects of two electrical stimulation frequencies in thigh muscle after knee surgery

The purpose of this study was to compare the effects of two protocols of electrical stimulation combined with voluntary contractions on the recovery of thigh muscles after anterior cruciate ligament (ACL) surgery. Ten sportsmen with a mean age of 26 yrs were randomly assigned into two groups: a 80 Hz stimulated group (5 patients) and a 20 Hz stimulated group (5 patients). All patients received electrical stimulation of the quadriceps femoris, five days a week, for 12 weeks, and had a standard program of voluntary contractions. Muscle and fat volumes of the thigh were assessed using MRI before surgery and after 12 weeks of rehabilitation. Quadriceps and hamstring muscle strength were evaluated by isokinetic measurements. Twelve weeks after surgery, the quadriceps peak torque deficit in the operated limb with respect to the non operated limb at 180 degrees /s and 240 degrees /s was significantly (p < 0.05) less in the 20 Hz group than in the 80 Hz group. This difference was not confirmed when comparing the pre-surgery quadriceps peak torque of the operated limb with the post-surgery one. Subcutaneous fat volume was increased for the two groups at the post-surgery test. This increase was significantly (p < 0.05) greater for the 80 Hz group. Thigh muscle volume deficit was not significantly different between the two groups.

Leber's hereditary optic neuropathy: heteroplasmy is likely to be significant in the expression of LHON in families with the 3460 ND1 mutation

AIM

To assess the effect of heteroplasmy on the expression of Leber's hereditary optic neuropathy (LHON) in a large family with the 3460 LHON mutation.

METHODS

Mutation detection was performed by restriction enzyme digestion of polymerase chain reaction (PCR) products. Heteroplasmy was estimated by quantitation of wild type:mutant product ratios.

RESULTS

There is a significant association between levels of mutant mtDNA and manifestation of the disease phenotype.

CONCLUSION

As a high proportion of families with the 3460 mutation demonstrate heteroplasmy; this is likely to be a significant factor in disease expression.

Leber's hereditary optic neuropathy: implications of the sex ratio for linkage studies in families with the 3460 ND1 mutation

Leber's hereditary optic neuropathy (LHON), which is associated with mutations in mitochondrial DNA (mtDNA), is commoner in males than females. A study of over 30 LHON families with a mutation at position 3460 of mtDNA demonstrates a significantly decreased male excess from that generally quoted, with evidence for a marked bias in the ascertainment of males over females. This has implications for the analysis of those factors which give rise to the male bias.

Plants that poison in Uruguay

Poisoning by plants has different traits in each country, according to geographical, botanical and also socio-cultural characteristics. The incidence of "plant calls" to the Poison Control Center in Uruguay is not very high, but it is due usually to symptomatic cases affecting children. Plant poisoning in adults is less frequent, being due to home-made medicine, and, in women, to the popular belief in the abortive quality of some plants. Suicide attempts are rare. The different species that cause consultations, and the clinical characteristics are briefly analyzed, as well as the problems that a Poison Control Center usually has to face in poisoning by plants.