Domestic Refugee Health Screening Guidance
Blood Lead Screening

Exposure to lead, a known neurotoxicant, remains a significant public health challenge, worldwide and within the state of Minnesota. While the blood lead reference value in the U.S. is 5 µg/dl, the effects of lead depend on the dose and literature indicates there is no “safe” level of exposure. Because of the frequently subtle and delayed impact of EBLL, a robust screening approach, partnership with communities and families, and clinical follow-up to EBLL is critical to improving outcomes. This may require service providers to connect families to resources that can address a variety of needs, including nutrition support, exposure assessment and remediation, housing assistance, and education.

Blood lead screening recommendations for the Refugee Health Assessment (RHA) differ from standard practice in the well-child check due to differing routes of exposure and the fact that many new arrivals may not have had access to lead screening previously. While exposure of U.S. children to lead occurs primarily from lead-based paint chips and dust in older homes, lead exposure still occurs through other routes in many parts of the world. This is due to combustion of leaded gasoline, smelters, chemical or battery plants, burning of fossil fuels and solid waste, ammunition manufacturing and use, use of lead as a bearing element in rural flour mills, uncontrolled recycling of lead-acid batteries, and traditional remedies or foods, where lead compounds are added to increase weight or as a dye. Several factors increase the potential for lead exposure in developing countries, including poor nutrition, environmental pollution, absent or lax environmental regulations, and continued use of lead-based paint in some countries (IPEN: Lead Levels in Paint Around the World).

A child’s lead exposure may begin in utero due to mobilization of maternal bone lead stores and ongoing maternal lead exposure, highlighting the importance of assessing pregnant and breastfeeding women when risk factors are present. Lead toxicity in pregnant women has been associated with an increased risk of spontaneous abortion, gestational hypertension, abnormal fetal neurodevelopment, and low birthweight. Additionally, strong evidence shows that prenatal lead exposure impairs children’s neurodevelopment, placing them at increased risk for developmental delay, reduced IQ, and behavioral problems. Because more than 90% of lead is stored in bone, it is thought that long-term exposure in women may cause lead to accumulate in bone and be released during times of higher metabolism, such as pregnancy and lactation, potentially placing the fetus or nursing infant at risk of exposure (CDC Lead Screening Guidelines: Clinical Presentation). Pregnant and breastfeeding immigrant women have a higher risk for having elevated blood lead levels upon arrival.

Reference:
Ettinger AS, Wengrovitz AG, editors. Centers for Disease Control and Prevention (CDC) Guidelines for the identification and management of lead exposure in pregnant and lactating women. Atlanta, GA: U.S. Department of Health and Human Services; 2010. pp. 1–267.

In Minnesota, around 90,000 children under the age of six receive a blood lead test each year. While Minnesota’s blood lead screening guidelines do not recommend universal testing for children in all areas of the state, the percentage of children tested has been increasing over time. At the same time, the number of elevated blood lead level (EBLL) cases has decreased in recent years. Less than 1% of children tested in Minnesota are found to have a blood lead level of at least 5 µg/dl. This translates to roughly 700 children under age six with a confirmed EBLL of at least 5 µg/dl, including 90 children under age six with a confirmed EBLL of at least 15 mcg/dL, each year in Minnesota. EBLLs do not occur uniformly throughout Minnesota; rather, they tend to concentrate in areas with older housing.

Among refugees who arrived in Minnesota from 2009-2018, 95% of refugee children under 17 years were tested for lead poisoning. Twelve percent of those had an EBLL ≥5 µg/dl, including 2% with an EBLL ≥10 µg/dl. Though there was a higher prevalence of EBLL among younger children, ten percent of refugee children ages 7 to 16 had an EBLL ≥5 µg/dl, including 1% with an EBLL ≥10 µg/dl It is also of interest that EBLL prevalence varies between countries of origin. Afghani arrivals have experienced significantly higher prevalence of EBLL, in part due to lead contamination in traditional products such as kohl (an eyeliner used on children).

Lead Poisoning among Primary Refugees to Minnesota by Age, 2009-2018

Lead Poisoning among Primary Refugees to Minnesota by Country of Origin, 2009-2018

*Refugee Health Assessment (RHA): health screening done in U.S., usually within 90 days of U.S. arrival
**Tested during post-arrival Refugee Health Assessment