Educational Impacts of Lead Exposure

Every year, thousands of children are exposed to the dangers of lead in their own homes. Lead exposure affects a child’s ability to grow, think, learn, relax, and form critical early bonds; these impacts on a child’s educational outcomes are substantial. In this story, we will explore lead exposure among Rhode Island children and examine its impacts on various educational measures.

Lead exposure impacts a child’s ability to obtain a good education and succeed in school. Common sources of lead include paint, dust, and drinking water. Lead can affect how a child’s brain develops, making it difficult for a child to learn.

Lead can be a marker for a variety of unhealthy housing conditions that can affect not only a child’s ability to learn, but also whether a child is healthy enough to attend school at all.

Rhode Island requires that all children receive two blood lead screening tests prior to 36 months of age. While approximately 65% of children are screened at least once by 18 months, only about 45% are screened twice by 36 months. For children with multiple confirmed blood lead level (BLL) tests on file, the highest recorded result or “Max BLL” was used.

This story refers to children without a BLL test as "Not Tested." These students may have come from out-of-state or sought exemption for religious reasons. While lead screening is required, schools do not have to exclude children if they have not been tested.

BLL screening results are reported by the amount of lead in micrograms per deciliter of blood (µg/dL). As of 2012, the Centers for Disease Control and Prevention’s (CDC) reference level for children who have been exposed to lead is 5 µg/dL or above. CDC created this lower reference level based on scientific evidence that BLLs below 10 µg/dL (the previous "level of concern") can have adverse health effects in children.

References: CDC, RI Department of Health, Childhood Lead Poisoning  

Though lead exposure has decreased in recent years, 1 in every 14 rising kindergarten student has had a blood lead level of 5 µg/dL or above.

The percent of children eligible to enter kindergarten in Rhode Island who have a test result with an elevated blood lead level (greater than or equal to 5 µg/dL) has decreased from 8% to 7% between 2016 and 2019. Above, you can see the distribution of lead level categories across Rhode Island municipalities.

Source: Rhode Island Department of Health Lead Elimination Surveillance System (collects lead screening results for all children in the state)

Note: Two schools are shown together to limit suppression. Results are suppressed for denominators of less than 10 and numerators between 1 and 4.

From 2016 to 2019, there has been a promising decrease in the prevalence of elevated blood lead levels in Rhode Island children.

In the interactive dashboard above, you can easily see which districts have the highest concentration of students in grades Kindergarten through five who have ever had elevated blood lead levels. Additionally, in 2016, six municipalities had prevalence rates over 20%; whereas the no municipalities had prevalence rates greater than 20% in 2019.

Again, you may use the indicator selector to change the coloring of the map if you’re interested in other categories of lead exposure.

Note: The denominator for displayed percentages is total students tested, not total students. Not all schools have comparable percentages of students with matched lead test data.

Each component of unhealthy housing is prevalent in urban areas.

The map is a composite analysis of three key indicators of unhealthy housing:

1. Percent of children younger than six years old with first-time elevated blood lead levels (5+ µg/dL)
2. Percent of housing units built before 1950
3. Median family income

Each indicator was tallied by census tract and calculated according to the category of most concern (increasing values for all measures except median family income), then combined into a ranking of unhealthy housing.

As exposure to lead increases, so does student absenteeism.

Families encounter a number of challenges when they are exposed to unhealthy environmental conditions. Unhealthy housing can be associated with chronic sickness in children keeping them out of school. Research finds that asthma contributes to higher levels of absenteeism. Concurrently, lead exposure has been found to be a reliable proxy for unhealthy environmental conditions that exacerbate asthma.

Grade retention also increases with increased exposure to lead.

Grade retention refers to the number of students who are "held back" and asked to repeat a year of school. Given the cognitive and developmental delays linked to elevated BLL in children, we would expect to see an association between BLL and grade retention.

In the 2018-19 school year 9% of all students in the lowest BLL category had ever been retained as opposed to 12% of students in the highest BLL category.

While grade retention is intended to give struggling students additional time and support to master grade-level goals, studies show mixed results on academic performance. Additionally, research has shown retained students to be more likely to have a myriad of social, behavioral, and emotional problems in the future. Grade retention is one of the most powerful predictors of dropout status and is linked to lower future earnings.

Students in the lowest lead exposure category consistently outperformed their peers with higher BLLs on statewide assessments.

Children with elevated blood lead levels have been found to demonstrate decreased cognitive functioning and to have lower IQ scores. This has very real implications for the classroom with studies finding that these students typically have lower scores on measures of math and reading abilities, nonverbal reasoning, vocabulary and grammatical reasoning and short-term memory.

These bar charts show a great disparity in the academic performance of Rhode Island 3rd graders. For the 2018-19 school year, 46% of students with the lowest blood lead levels were proficient in reading whereas only 35% of students in the highest BLL category were proficient.

Standardized tests have been used prominently in the American education system for more than 50 years and remain one of the most common ways to assess student knowledge. Rhode Island students in Grades 3-8 take the RICAS (Rhode Island Comprehensive Assessment System) math and reading exams every spring. The RICAS tests are designed to measure the content knowledge and skills that students are expected to have mastered as they finish the school year in their current grade. Students who score below proficient may need additional instructional supports to meet grade-level expectations.

Note: ELLs = English language learners

Children with higher blood lead levels are more likely to require an Individual Education Plan.

Research has shown a strong association between lead poisoning in children and IQ loss and learning disabilities. As a result, many lead-exposed children may require special education services, or Individual Education Plans (IEP) services.

Above, you can compare the association between students’ blood lead levels and whether they were identified as needing IEP services. Use the top menu to see the breakdown by grade or by maximum blood lead levels for students enrolled in kindergarten through eighth grades in Rhode Island public schools. Across all grade levels you can see that students with elevated blood lead levels are more likely to receive an IEP.

When taken as a whole, kindergarten through fifth grade students with an elevated BLL (≥ 5 µg/dL) are four percentage points more likely to have an IEP than their non-exposed peers (<5 µg/dL).

Although researchers agree that there is no “safe” level of lead exposure, other factors in a child’s life can affect cognitive development. While we cannot be certain which students’ IEP services are attributable to lead exposure, the next slide begins to estimate what lead-related IEPs may cost the state.

Additionally, in the visualization above, you can compare elevated BLL with a variety of other equity cuts including:

• Sex
• Race/Ethnicity
• English Language Proficiency
• Economically disadvantaged 

The linked data analysis clearly shows an association between lead exposure and:

• Lower state assessment scores
• Higher rates of absenteeism
• Grade retention
• Increased IEPs

Children who test below proficient on the state assessments may find it harder to graduate from high school. The need to stay home from school or repeat a grade can also affect a child’s quality of life and potential to succeed.

Costs of lead poisoning, such as special education costs, lost future earnings, or other costs associated with compromised health, may put a strain on parents and families as well as the fiscal health of the state.

These results provide evidence that lead exposure can substantially impact the lives of children in Rhode Island.

Unfortunately, lead exposure is often not a concern until after an elevated blood lead level is identified upon screening.

If, instead, we recognize environmental factors as a potential source of illness, we can identify ways to stop hazards from affecting children at all. This concept, primary prevention, is the best solution for protecting children’s health. In general, efforts should target high-risk neighborhoods. Basic strategies consist of: regular lead screenings, increased education and outreach, checking homes for hazards, enforcement of lead safe housing requirements, remediating any lead hazards, and maintaining a safe and healthy home.

The Rhode Island Department of Health recommendations for lead screenings are:

• One lead test by 15 months, and a second test at least 12 months later
• Two lead tests by 36 months, and then annual screenings until the age of 6

Identifying, controlling, and preventing lead health hazards could lead to improved outcomes for future students in Rhode Island.

References: Alliance for Healthy Homes, CDC Guidance on GIS Use, National Center for Healthy Housing