Abstract Lead is a naturally occurring element that has been used by humankind for millennia, but a growing body of evidence confirms its serious toxicity for virtually all bodily systems. This paper reviews and discusses the relevant peer-reviewed and academic literature concerning lead exposure and poisoning and to determine their effects children’s academic performance. In addition, a discussion concerning the implications of the adverse effect of lead exposure and poisoning on children’s performance at school is followed by a summary of the research and important findings concerning these issues in the conclusion.

The Effect of Lead Poisoning on Children's Performance at School

Although it is a preventable disease, lead exposure in general and lead poisoning among children in particular remains a serious problem in the United States today. Lead poisoning is caused by the consumption of lead in some form including dust particles and lead-based paint chips (Lead poisoning still leads in environmental risk issues, 2009). Lead poisoning can affect individuals of any age from virtually any walk of life, but minority young people from lower socioeconomic families tend to suffer disproportionately in spite of aggressive efforts by the federal government to reduce the use of lead in occupational settings as well as in household paints and gasoline products (Lead poisoning, 2009) and even the lead solder used in household and commercial plumbing (Miranda & Anthopolos, 2011). In fact, current estimates indicate that at least 4 million young people in America live are at risk (Children and lead poisoning, 2017) and between a half million (McGill, 2013) and one million children in the U. S. already have dangerously high blood levels of lead above 5 micrograms per deciliter, the level at which the U.S. Centers for Disease Control recommends the commencement of public health actions (Lead poisoning, 2009). To determine the facts about this troubling this issue, this paper provides a review and discussion of the relevant literature to provide an overview of lead and lead poisoning and to determine the effect of lead poisoning on children’s performance at school. Finally, a discussion concerning the implications of lead poisoning’s adverse effect on children’s academic performance is followed by a summary of the research and important findings concerning the effect of lead poisoning on children’s academic performance are provided in the conclusion.

Overview of lead, lead exposure and lead poisoning

Although the element has a number of valuable commercial uses (Learn about lead, 2017), lead is enormously toxic to humans and there have been no safe blood lead levels for children identified in the research to date (Lead, 2017). In fact, lead poisoning is currently the most common environmental health problem affecting children in the United States (Endres & Montgomery, 2009). Although adults are also at risk, children are at greater risk of being harmed by lead exposure because the substance is more readily absorbed by them compared to adults, and their body tissues are especially sensitive to the harmful effects of lead (Currie, 2010). The high level of toxicity also means that exposure to lead can adversely impact almost all bodily systems (Lead, 2017).

Exposure to lead, however, may go unnoticed in children because there may not be any clearly discernible symptoms (Lead, 2017). Some of the more common symptoms and signs of lead poisoning in children include the following:

· Developmental delay;

· Learning difficulties;

· Irritability;

· Loss of appetite;

· Weight loss;

· Sluggishness and fatigue;

· Abdominal pain;

· Vomiting;

· Constipation;

· Hearing loss;

· Seizures; and,

· Pica (i.e., eating paint chips) (Overview of lead poisoning, 2017).

Moreover, these symptoms can persist well into adolescent and adulthood as well (Endres & Montgomery, 2009).

Although the majority of American homes constructed prior...

Current estimates indicate that there are approximately 64 million housing units that contain lead paints in the United States today, and the overwhelming majority of these housing units are occupied by urban-dwelling, lower-income families (Overview of lead poisoning, 2017). As shown in Figure 1 below, American children who live in housing units that were constructed prior to 1978 are at far greater risk of experiencing lead exposure as a result of lead-based household paints (McGill, 2013).
Figure 1. Percentage of American homes likely to contain lead-based paint based on year built

Source: https://www.epa.gov/sites/production/files/lead/images/olderhomes.jpg

Likewise, schools and daycare facilities for children built prior to 1978 may also represent a source of lead poisoning (Overview of lead poisoning, 2017). Indeed, even soil, cookware, toys and playground equipment with lead-based paint can cause lead poisoning in children (Overview of lead poisoning, 2017). In addition, children living within 500 miles of airports where aircraft use leaded aviation gas suffer higher blood lead levels compared to other children (Miranda & Anthopolos, 2011). Indeed, Miranda and Anthopolos emphasize that, “Lead emitted from aircraft using leaded aviation gasoline (avgas) is currently the largest source of lead in air in the United States, constituting about 50% of lead emissions in the 2005 National Emissions Inventory” (p. 1514). Here again, because many lower-income residences are located in geographic proximity to airports, children from lower socioeconomic families are at higher risk of lead exposure and poisoning.

Despite these troubling issues, the good news is that blood lead concentrations in American have experienced significant and sustained decreases over the past 4 decades due to legislation and stricter standards for lead-based products as shown in Figure 2 below.

Figure 2. Timeline of lead poisoning prevention policies and blood lead levels in children aged 1–5 years, by year

Source: Prevention of childhood lead toxicity, 2017, p. 2

Notwithstanding this progress, though, the bad news is that hundreds of thousands and perhaps even millions of poor American young people are already suffering from elevated blood lead levels and many remain exposed to various sources of lead that are not typically shared by their more affluent counterparts. Many children from lower-income families continue to live in housing units with aging lead and corresponding elevated lead dust levels placing them at greater risk of lead exposure and poisoning and the corresponding academic deficits this can cause (Prevention of childhood lead toxicity, 2017). According to the American Academy of Pediatrics, “Evidence continues to accrue that commonly encountered blood lead concentrations, even those below 5 µg/d (50 ppb), impair cognition [and] there is no identified threshold or safe level of lead in blood” (p. 1). The most recent research shows that during the period from 2007 through 2010, more than half a million preschool students aged 1 to 5 years (about 2.6%) in the U.S. suffered from elevated blood level concentrations equal to or greater than 5 µg/d (Prevention of childhood lead toxicity, 2017).

As show in Figure 3 below, there are also a number of additional sources besides lead-based paints that place all American children at risk of lead exposure,

Figure 2. Respective contributions of lead exposure to children’s blood lead concentrations, Source: Prevention of childhood lead toxicity, 2017, p. 6

In most cases of lead poisoning, though, these sources of lead exposure have been shown to inordinately affect lower-income and minority children, but whenever housing units are renovated, the potential for exposure to lead becomes greater for families of all socioeconomic categories (Lead poisoning, 2009). Taken together, these trends indicate that a surprising number of American children are being slowly poisoned by their environments, but…