Abstract
Objectives. To (1) determine the prevalence of elevated blood lead levels (EBLLs; ≥ 5 µg/dL) among newly arrived refugee children, (2) understand the demographic characteristics of refugee children with EBLLs, and (3) assess health care providers’ compliance with Centers for Disease Control and Prevention (CDC) recommendations for retesting.
Methods. We matched refugee demographic data (2015–2019) from the CDC’s Electronic Disease Notification (EDN) system with lead-testing laboratory report data from the Pennsylvania National Electronic Disease Surveillance System using Match*Pro software.
Results. Of 3833 refugee children 16 years or younger in the EDN system, matching identified 3142 children with blood lead level data. Among children with blood lead level data, 578 (18.4%) had EBLLs. Among children with EBLLs, 341 (59.0%) were male. Of the 1370 children aged 6 years or younger with blood level test results, 335 (24.5%) had initial EBLLs, and only 78 (5.7%) were retested within 3 to 6 months. Of the 335 children 6 years or younger with an initial EBLL, only 44 (13.1%) were retested within 3 to 6 months.
Conclusions. Following up on refugee children with EBLLs is necessary to ensure that they do not have continued lead exposure. (Am J Public Health. 2022;112(S7):S706–S714. https://doi.org/10.2105/AJPH.2022.306856)
In 2012, the Centers for Disease Control and Prevention (CDC) defined a blood lead level of 5 micrograms per deciliter (µg/dL) or higher as an elevated blood lead level (EBLL). The CDC recommended screening refugee children aged 6 months to 16 years on arrival to the United States and retesting refugee children aged 6 years or younger 3 to 6 months after initial testing, regardless of initial screening result. The CDC also recommended that children aged 7 to 16 years with EBLLs be retested 3 to 6 months after initial screening. Recently, the CDC updated its EBLL in children from 5 µg/dL to 3.5 µg/dL in response to the Lead Exposure Prevention and Advisory Committee recommendation made May 14, 2021.1
Lead has no physiologic role in the human body, and any level is potentially harmful. Exposure to lead can cause intellectual, behavioral, and academic deficits in children.2,3 Children are particularly at risk for lead exposure because of such behaviors as playing on the floor and mouthing objects that increase contact with dust, dirt, and surfaces potentially contaminated with lead.4 Children younger than 6 years are more vulnerable to the toxic effect of lead exposure because of their rapidly developing nervous systems, which are more sensitive to the effects of lead.5 Studies have indicated that children’s exposure to lead, even at low levels, can cause intellectual deficits.2,6
Many low- to middle-income countries continue to use lead in paints and consumer products. Lead exposure is also an occupational hazard in manufacturing and mining processes in low- to middle-income countries.7 Refugee children have previously been identified as a population at high risk for lead exposure.8–10 Refugee children are especially at higher risk for lead poisoning because of anemia and malnutrition, which increase lead absorption.11,12 In addition, refugee children arrive in the United States with iron deficient anemia, which augments the absorption of lead in the gastrointestinal tract.13 Lead exposures among newly arrived refugees may include historical environmental and occupational exposures and exposures from household and personal items. Moreover, refugees may continue to use or consume products contaminated with lead, such as traditional remedies, herbal supplements, spices, candies, cosmetics, and jewelry in the United States.14 Refugees’ EBLLs reported based on initial medical screening within 30 to 90 days of their arrival in the United States likely indicate overseas exposure to lead in their home countries or in refugee camps. The prevalence of EBLLs among refugee children is not well documented in Pennsylvania and understanding lead levels in this population is critical for ensuring follow-up and treatment of EBLLs.
Pennsylvania receives a significant number of refugees (including asylees, Cuban Haitian parolees, and Special Immigrant Visa recipients) for resettlement in the United States. Pennsylvania was ranked top (ranged from 5th to 10th positions) among the states in the nation in number of refugees resettled during the past 10 years.15 Refugees receive mandatory overseas predeparture medical screening before arriving in the United States. Data from these screenings are reported to the CDC’s Electronic Disease Notification (EDN) system. The EDN system is a centralized electronic reporting system that notifies the US state and local health departments and screening clinics of the arrival of refugees and immigrants with health conditions requiring medical follow-up.
The primary purpose of the overseas medical examination is to identify refugees with inadmissible health-related conditions. More than 760 physicians perform overseas predeparture medical examinations in accordance with technical instructions provided by the CDC.16 The overseas medical examination does not include blood lead level screening. Refugees undergo further comprehensive medical examination within 30 to 90 days of arriving in the United States. The comprehensive examination includes a medical history and physical examination, screening for select communicable diseases, nutritional status assessment, blood lead screening (for children aged 16 years or younger and all newly arrived pregnant or lactating women and girls), and immunizations administration according to US schedules.14 The reportable conditions identified during the comprehensive medical examination, including blood lead levels, are reported to the Pennsylvania National Electronic Disease Surveillance System (PA-NEDSS).
Currently, systematic evaluations of blood lead levels and follow-up tests among the refugee population are not routinely done. Matching the refugee health records from the EDN system with PA-NEDSS blood lead results using a probabilistic matching method provides the ability to track blood lead–testing results of refugee children at the individual level and to assess whether they have been follow-up tested or retested properly to assess whether lead levels are increasing or decreasing.
We sought to (1) determine the prevalence of EBLLs (≥ 5 µg/dL) among newly arrived refugee children at resettlement, (2) understand the demographic characteristics of refugee children with EBLLs, and (3) assess health care providers’ compliance with CDC recommendations for retesting 3 to 6 months after the initial test.
METHODS
We matched refugees’ demographic data from the EDN system (2015–2019) with the 2015–2020 lead-testing laboratory report data in PA-NEDSS using identifiable patient information such as patient first, middle, and last names; gender; date of birth; and residential address. We used Match*Pro software version 1.6.4 (Information Management Services, Inc., Modesto, CA) for the probability matching process. Match*Pro is a Java-based application for conducting probabilistic record linkages. We manually examined matched pairs with lower match scores to ensure proper matching. We grouped refugee children into 2 age groups based on their first lead-testing dates: aged 6 years or younger (6 months to 6 years) and aged 7 to 16 years. We considered children with 1 venous blood lead level of 5 µg/dL or higher or 2 capillary blood lead levels of 5 µg/dL or higher within 84 days as having confirmed EBLL.17
We considered children with 1 capillary blood lead level of 5 µg/dL or higher without follow-up testing as having unconfirmed EBLL.17 We calculated the geometric mean (GM) and SE of blood lead levels using the initial lead test value regardless of specimen source. We used GM considering the log-normal distribution of blood lead levels. For analysis, we replaced a value of less than the minimum detectable level (MDL) of blood lead by MDL/√2, and we used a value of 2/√2 when the MDL was not available. We performed data analysis using SAS software, version 9.4 (SAS Institute, Inc., Cary, NC).
RESULTS
Of 3833 refugee children aged 16 years or younger in the EDN system (2015–2019), probability matching identified 3142 (82.0%) children with blood lead level data in PA-NEDSS (Figure 1) with 4176 blood lead tests. A total of 1370 of the 1515 (90.4%) children aged 6 years or younger and 1772 of the 2318 (76.4%) children aged 7 to 16 years were matched to lead tests reported in PA-NEDSS (Figure 1), and 52.0% (1635) of matched children aged 16 years or younger were male. Of the 691 refugee children aged 16 years or younger with unmatched lead tests, 145 (21.0%) were aged 6 years or younger and 546 (79.0%) were aged 7 to 16 years.
FIGURE 1—
Number of Refugee Children Aged 16 Years or Younger From the EDN System Matched With Blood Lead Level Data Reported in Pennsylvania National Electronic Disease Surveillance System (PA-NEDSS): 2015–2020
Note. EDN = Electronic Disease Notification.
Table 1 shows the number and percentage of refugee children aged 16 years or younger with EBLL status. Of the 1370 children aged 6 years or younger, 328 (23.9%) and of the 1772 children aged 7 to 16 years, 250 (14.1%) had either confirmed or unconfirmed EBLLs. Among the 3142 children aged 16 years or younger with blood lead level data in PA-NEDSS, 578 (18.4%) had EBLLs. Among the 578 children aged 16 years or younger with EBLLs, 478 (82.7%) had a confirmed EBLL, and the remaining 17.3% had an unconfirmed EBLL. Boys were more likely to have EBLLs in both age groups (Table 1). A total of 341 (59.0%) children aged 16 years or younger with EBLLs were boys, and 283 (49.0%) boys had confirmed EBLLs.
TABLE 1—
Number of Refugee Children Aged 16 Years or Younger With Elevated Blood Lead Levels (EBLLs) and Mean Blood Lead Levels Based on Gender and Age Groups: Pennsylvania National Electronic Disease Surveillance System, 2015–2020
| Children’s Age Group | Children With Confirmed EBLLs,a No. (%) | Children With Unconfirmed EBLLs,b No. (%) | Children With EBLLs,c No. (%) | Children With No EBLLs Screening, No. (%) | Total No. Children | GM of Blood Lead Levelsd (SE) |
| 6 mo to 6 y | ||||||
| Female | 116 (18.0) | 19 (3.0) | 135 (21.0) | 508 (79.0) | 643 | 2.92 (1.025) |
| Male | 168 (23.1) | 25 (3.4) | 193 (26.5) | 534 (73.5) | 727 | 3.13 (1.025) |
| Total | 284 (20.7) | 44 (3.2) | 328 (23.9) | 1042 (76.1) | 1370 | 3.03 (1.018) |
| 7–16 y | ||||||
| Female | 79 (9.1) | 23 (2.7) | 102 (11.8) | 762 (88.2) | 864 | 2.25 (1.022) |
| Male | 115 (12.7) | 33 (3.6) | 148 (16.3) | 760 (83.7) | 908 | 2.60 (1.021) |
| Total | 194 (10.9) | 56 (3.2) | 250 (14.1) | 1522 (85.9) | 1772 | 2.43 (1.015) |
| 6 mo to 16 y | ||||||
| Female | 195 (12.9) | 42 (2.8) | 237 (15.7) | 1270 (84.3) | 1507 | 2.52 (1.017) |
| Male | 283 (17.3) | 58 (3.5) | 341 (20.9) | 1294 (79.1) | 1635 | 2.83 (1.016) |
| Total | 478 (15.2) | 100 (3.2) | 578 (18.4) | 2564 (81.6) | 3142 | 2.67 (1.012) |
Note. GM = geometric mean.
Children with 1 venous lead level of ≥ 5 µg/dL or 2 capillary lead levels ≥ 5 µg/dL, within 84 days.
Children with 1 capillary lead levels of ≥ 5 µg/dL without a confirmation test.
Sum of confirmed and unconfirmed EBLLs.
Less than minimum detectable level (MDL) of lead in blood was replaced by MDL/√ 2; a value of 2/√ 2 was used when no MDL was available.
Table 1 shows the GM and SE of blood lead levels based on age group and gender of the refugee children aged 16 years or younger. Refugee children aged 16 years or younger had blood lead levels with a GM of 2.6 7 µg/dL and an SE of 1.012. Boys younger than 16 years had higher blood lead levels (GM = 2.83 µg/dL; SE = 1.016) than did girls of the same age (GM = 2.52 µg/dL; SE = 1.017).
Table 2 shows the GM and SE of blood lead levels among refugee children aged 16 years or younger based on their country of birth. Among the 578 children aged 16 years or younger with EBLLs, 69 (11.9%) were from Afghanistan, 125 (21.6%) were from Nepal, and 67 (11.6%) were from Uganda. Sixty-nine of 157 (43.9%) children from Afghanistan, 125 of 364 (34.3%) from Nepal, and 67 of 203 (33.0%) children from Uganda had EBLLs. The GMs and SEs of blood lead levels among children from these countries were 4.27 µg/dL (SE = 1.051), 3.89 µg/dL (SE = 1.022), and 3.08 µg/dL (SE = 1.061) for Afghanistan, Nepal, and Uganda, respectively (Table 2).
TABLE 2—
Number of Refugee Children Aged 16 Years or Younger With Elevated Blood Lead Levels (EBLLs) and Mean Blood Lead Levels Based on Country of Birth: Pennsylvania National Electronic Disease Surveillance System, 2015–2020
| Birth Country | Children With Confirmed EBLLs,a No. | Children With Unconfirmed EBLLs,b No. | Children With EBLLs,c No. (%) | Children With No EBLLs, No. | Total No. Children | GM of Blood Lead Levelsd (SE) |
| Afghanistan | 66 | 3 | 69 (43.9) | 88 | 157 | 4.27 (1.051) |
| Belarus | 0 | 0 | 0 (0.0) | 31 | 31 | 1.51 (1.068) |
| Burundi | 21 | 14 | 35 (23.3) | 115 | 150 | 2.84 (1.053) |
| Democratic Republic of Congo | 24 | 4 | 28 (21.4) | 103 | 131 | 2.60 (1.066) |
| Eritrea | 2 | 3 | 5 (12.5) | 35 | 40 | 2.06 (1.105) |
| Ethiopia | 7 | 6 | 13 (17.8) | 60 | 73 | 2.66 (1.074) |
| India | 5 | 1 | 6 (23.1) | 20 | 26 | 3.51 (1.075) |
| Iraq | 11 | 1 | 12 (11.0) | 97 | 109 | 2.61 (1.057) |
| Jordan | 12 | . . . | 12 (11.4) | 93 | 105 | 2.73 (1.068) |
| Kenya | 16 | 2 | 18 (12.9) | 122 | 140 | 2.66 (1.051) |
| Malawi | 2 | 1 | 3 (12.5) | 21 | 24 | 3.59 (1.122) |
| Malaysia | 19 | 1 | 20 (16.3) | 103 | 123 | 2.88 (1.046) |
| Myanmar | 3 | . . . | 3 (6.5) | 43 | 46 | 2.67 (1.072) |
| Nepal | 114 | 11 | 125 (34.3) | 239 | 364 | 3.89 (1.022) |
| Pakistan | 8 | 4 | 12 (38.7) | 19 | 31 | 3.62 (1.114) |
| Rwanda | 5 | 3 | 8 (10.0) | 72 | 80 | 2.04 (1.080) |
| Somalia | 2 | 17 | 19 (26.0) | 54 | 73 | 3.05 (1.074) |
| South Africa | 4 | . . . | 4 (12.1) | 29 | 33 | 2.54 (1.116) |
| Sudan | 2 | 3 | 5 (20.0) | 20 | 25 | 2.65 (1.155) |
| Syria | 20 | 5 | 25 (5.5) | 427 | 452 | 2.22 (1.022) |
| Thailand | 12 | . . . | 12 (25.5) | 35 | 47 | 3.80 (1.100) |
| Uganda | 62 | 5 | 67 (33.0) | 136 | 203 | 3.08 (1.061) |
| Ukraine | 2 | 1 | 3 (1.8) | 163 | 166 | 1.48 (1.046) |
| United Republic of Tanzania | 22 | 3 | 25 (8.8) | 259 | 284 | 2.05 (1.037) |
| Zambia | 4 | 3 | 7 (17.9) | 32 | 39 | 2.98 (1.089) |
| Other countries | 33 | 9 | 42 (22.1) | 148 | 190 | 2.74 (1.051) |
| Total | 478 | 100 | 578 (18.4) | 2564 | 3142 | 2.67 (1.012) |
Note. GM = geometric mean.
Children with 1 venous lead level of ≥ 5 µg/dL or 2 capillary lead levels of ≥ 5µg/dL, within 84 days.
Children with 1 capillary lead levels of ≥ 5 µg/dL without a confirmation test.
Sum of confirmed and unconfirmed EBLLs.
Less than minimum detectable level (MDL) of lead in blood was replaced by MDL/√ 2; a value of 2/√ 2 was used when no MDL was available. In 2019, the average prevalence of EBLLs of all children ≤ 16 y in Pennsylvania was 2.5%.
Of 3142 children aged 16 years or younger with test results in PA-NEDSS, the mean ages and SEs for these children by country were 6.6 (SE = 0.33), 6.9 (SE = 0.22), and 6.6 (SE = 0.29) years for children from Afghanistan, Nepal, and Uganda, respectively. However, of 578 children aged 16 years or younger with EBLLs, the mean age of children from Afghanistan, Nepal, and Uganda was lower compared with all children aged 16 years or younger. The mean ages and SEs for children with EBLLs were 5.7 (SE = 0.45), 5.9 (SE = 0.33), and 5.6, (SE = 0.43) years for children from Afghanistan, Nepal, and Uganda, respectively (data not shown).
Figure 2 shows the timing of blood lead retesting of children aged 16 years or younger based on the age groups and initial blood lead levels. Of 1370 children aged 6 years or younger with blood lead level test results, 335 (24.5%) had initial EBLLs. Among 1035 children aged 6 years or younger without an initial EBLL, only 34 (3.3%) were retested within 3 to 6 months, 785 (75.8%) were not retested, and others were retested before 3 months or after 6 months. Only 44 of 335 (13.1%) children aged 6 years or younger with an initial EBLL were retested within 3 to 6 months, 145 (43.3%) were not retested, and others were retested before 3 months or after 6 months. Overall, only 78 of the 1370 children aged 6 years or younger (5.7%) were retested within 3 to 6 months, including 44 with EBLLs. There was no retesting for 930 (67.9%) of the 1370 children aged 6 years or younger, including 145 with EBLLs.
FIGURE 2—
Time of Blood Lead Retesting After the Initial Test Based on the Age Groups of Refugee Children and Their Initial Blood Lead Levels (EBLLs): Pennsylvania National Electronic Disease Surveillance System, 2015–2020
Of the 1772 children aged 7 to 16 years with blood lead test results, 253 (14.3%) had initial EBLLs. Among children aged 7 to 16 years with EBLLs, 19 (7.5%) were retested within 3 to 6 months. No retesting was reported for 179 (70.8%) children aged 7 to 16 years with EBLLs. Retesting lead levels in less than 3 months or after 6 months were reported for 55 (21.7%) children aged 7 to 16 years with EBLLs (Figure 2).
Only 16.5% (97 of 588) of refugee children aged 16 years or younger received blood lead level follow-up tests within the CDC’s recommended time frame of within 3 to 6 months of the initial test. Among refugee children aged 16 years or younger with EBLLs, 10.7% (63 of 588) were retested within 3 to 6 months (Figure 2).
DISCUSSION
Our analysis revealed that approximately 18% of the newly arrived refugee children aged 16 years or younger had EBLLs based on the initial medical screening. Refugee boys aged 6 years or younger are more likely to have EBLLs. We also found that the follow-up test recommended by the CDC was not adequately conducted among the newly resettled refugee children in Pennsylvania. Only 13.1% of children aged 6 years or younger with an initial EBLL was retested within 3 to 6 months; 43.3% were not retested, and others were retested before 3 months or after 6 months.
It is documented that refugee children arriving in the United States have a higher prevalence of EBLLs than do children born in the United States.8,18,19 The prevalence of EBLLs was high among younger refugee children and refugee boys. Our analysis is consistent with those findings and found that children aged 6 years or younger had a higher EBLL (24%) than did children aged 7 to 16 years (14%) and boys were more likely to have EBLLs (59.0%) than were girls. A previous study reported that younger age and male sex (regardless of age) were associated with EBLLs at arrival and that the oldest refugee children (aged 12–16 years) had a lower EBLL prevalence (14%) than did refugee children aged 2 to 4 years (24%).9 Another study reported a higher risk of EBLLs in younger children (median age = 8 years), and refugee boys were 2 times more likely than were girls to have EBLLs.20 Shakya and Bhatta have reported that among refugee children resettled in Ohio, those younger than 6 years (27.0%) have a higher prevalence of EBLLs than do those aged 6 to 17 years (18.8%) and that boys (24.7%) have a higher prevalence of EBLLs than do girls (19.7%).10
We hypothesize that boys tend to play outdoors more often, increasing their contact with environmental lead pollutants in soil, dust, and dirt. Similarly, younger children have a tendency to mouth objects and spend more time on the floor. Commonly, these exposures occur simultaneously, making it difficult to identify and quantify the individual contribution of each lead source. EBLLs could also be related to iron deficiency in their country of origin, which increases absorption of lead from the gastrointestinal tract. The relationship between blood lead levels and iron were reported to be different between boys and girls, with an inverse and significant relationship in girls.21 In 2019, the average prevalence of EBLLs among all children aged 16 years or younger in Pennsylvania was 2.5%, which is more than 7 times lower than the 18.4% prevalence of EBLLs reported for refugee children reported in this study. The Pennsylvania childhood lead surveillance program reported a 3.4% prevalence of EBLLs among children aged 6 years or younger residing in Pennsylvania in 2019.22 The prevalence rate of confirmed EBLLs in refugee children younger than 6 years was 20.7%, which is 6 times the rate of the nonrefugee children.
The majority of refugees arriving in Pennsylvania received a medical examination within 30 days of arrival. The half-life of blood lead levels is approximately 30 days.23 Therefore, initial EBLLs of refugee children indicate primarily overseas exposure to lead in their home countries as well as in refugee camps. Lead exposure in refugee camps can be exacerbated by social and health conditions, including overcrowding, dusty environments, and deficiency of minerals such as iron in the diet, which can enhance lead absorption.24 Country of birth could be a risk factor for EBLLs for many refugee children. Children born in Afghanistan, Nepal, and Uganda had a greater GM for blood lead level than did refugee children born in other countries (Table 2). Another study reported that refugee children in the United States resettled from Afghanistan had a higher proportion (38.1%) of EBLLs than did children resettled from 19 other countries.20 This proportion is lower than the prevalence of 43.9% observed among refugee children from Afghanistan with EBLLs in this Pennsylvania study. Based on an analysis of blood lead levels of refugee children from 46 countries, a previous study reported a high prevalence of EBLLs (56.2%) among children from Afghanistan and Nepal (44.0%).10 Pezzi et al. reported EBLL prevalence of 27.5% and 21.3% for refugee children from Nepal and Uganda, respectively.9
Our findings highlight the broad environmental, social, and health risks faced by refugee children based on their country of birth. There have been reports of lead exposure among children from Afghanistan and Nepal that were attributable to the use of lead-containing eye cosmetics (such as kajal or surma), the use of which is a common cultural practice in those countries.25,26 A study from Greece reported that the probability of EBLLs was greater among refugee and migrant children from Asia than those from Africa or Europe.27
Children from Uganda are often born in refugee camps. The high lead environments, malnourishment, and deficiency of micronutrients in the diets including iron in refugee camps may contribute to EBLL in children from Uganda. The high prevalence of EBLLs and variation based on country of birth among resettled refugee children in the United States indicate the need for guidelines for health care providers and resettlement agencies to address EBLLs at the time of resettling, prevention of further lead exposure after resettling, and an increase in awareness of lead toxicity among these high-risk children. Refugee children are at high risk for lead exposure after resettlement in the United States. Studies have identified postresettlement increases in blood lead levels attributable to housing in old buildings with greater lead hazards.24,28,29 Therefore, it is important to follow up and treat refugee children aged 16 years and younger with EBLLs after resettling in the United States.
This Pennsylvania study indicated that 5.7% of children aged 6 years or younger and 7.5% of children aged 7 to 16 years with EBLLs were appropriately retested for blood lead levels per CDC recommendation. In another study based on lead-screening results of refugee children aged 6 months to 16 years who arrived in Virginia between October 1, 2003, and October 31, 2016, Seifu et al. reported that only 8.0% of children aged 6 years or younger without EBLLs on initial screening received rescreening within the CDC recommended time frame, whereas 59.0% of children aged 6 months to 16 years with EBLLs received retesting within 3 to 6 months of the initial test.20 These results highlight the need to conduct follow-up (retesting) on refugee children arriving in Pennsylvania to ensure that these children do not have continued exposure to lead.
The lack of retesting of blood lead levels among refugee children may be attributable to parents’ lack of awareness of lead toxicity. Other socioeconomic factors, such as limited access to transportation to the testing clinics and parents’ lack of time off from work for clinic appointments, could also be contributing to low levels of retesting. It is important to increase refugees’ health literacy on lead toxicity, the importance of lead screening, and the need for adequate follow-up. Health disparities in terms of childhood lead poisoning may be linked to culture- and language-specific barriers in the resettlement process.13 Caron et al. highlighted the importance of following a culture-centered approach to communication that incorporates the refugee’s culture, the community that they are resettled in, and their preferences for how the health information is shared with them.13 Refugee children continue to experience EBLLs after arrival in the United States as well. Environmental exposures, poor nutritional status, occupational exposures, cultural practices, and poor-quality housing because of low socioeconomic status may all be contributing factors for EBLLs in refugee children after resettling in the United States.
Health care providers may not be aware of the CDC’s recommendation and so use guidelines for children born in United States to testing refugee children. Health care providers can play a major role in creating awareness among parents of lead toxicity and the importance of timely retesting for blood lead levels. Health care providers should be frequently reminded about the importance of repeat lead screening of children aged 6 years and younger, irrespective of their initial blood test results, and retesting of children aged 7 to 16 years with EBLLs. Health care provider education on the importance of follow-up testing needs to be enhanced to ensure compliance with CDC recommendations, especially for this high-risk refugee population. Knowledge of the prevalence of EBLLs will assist public health in designing outreach programs for this culturally and linguistically diverse population. The CDC’s recent decision to lower the reference blood lead level to 3.5 µg/dL highlights even more the need to appropriately test and follow up these high-risk refugee children.
Limitations
There are a few limitations to our study. First, we used the probability match process, which used the patient’s name, gender, date of birth, and residential address for matching purposes. The refugee family could have moved or resettled to another state and thus may not have matched. However, we matched almost 90% of children aged 16 years and younger with our lead-testing data. The remaining unmatched 10% needs to be further investigated to see whether they truly were not tested or they resettled to another state. Second, we hypothesized the possible exposure route for those children with EBLLs, but the true exposure history and source requires a custom survey with refugee families to ask about the exposure histories before arriving in the United States. Third, the low compliance rate for retesting is intriguing and worth investigating. We can only hypothesize the reason in our discussion, and this requires further investigation.
Conclusions
Lead poisoning is a serious health condition for refugee children arriving in the United States. EBLL prevalences were higher in younger and male refugee children who arrived in Pennsylvania and varied depending on the country of birth. The majority of refugee children who arrived in Pennsylvania from 2015 to 2019 were not retested for blood lead levels per CDC recommendations. The CDC’s recommended screening is especially important in the case of refugee children because they often arrive in the United States with significant overseas exposure and are more likely to have continued exposure to lead because of sociocultural issues after resettlement.
ACKNOWLEDGMENTS
The authors would like to thank the Pennsylvania Refugee Health Program.
CONFLICTS OF INTEREST
The authors have no conflicts of interest to disclose.
HUMAN PARTICIPANT PROTECTION
Institutional review board approval was not required because this project is a public health surveillance evaluation that used existing data.
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