Unleaded:
The Efficacy of the HELP Lead Safe Center in Reducing Blood Lead Levels in Children

Rachael Lynn Weiss
Bachelor of Arts in Environmental Studies
May 2003

The HELP Lead Safe Center (LSC) was created to reduce the impact of lead poisoning in children referred to the center by the Rhode Island Department of Health (RIDOH).  After thorough analysis of the blood lead levels (BLLs) of children in the LSC database, I determined that is no quick method of reducing a child’s BLL once poisoned.  My conclusions emphasize the importance of primary prevention to eliminate residential lead hazards before a child is exposed to lead.    

Source data were derived from the LSC’s comprehensive database as well as from statewide data on environmental lead inspections and lead screenings provided by the RIDOH.  The first set of analyses sought to determine the success of the LSC in lowering the BLLs of the children referred to case management.  Consequent analyses evaluated the effect that certain variables (such as case length, referral BLL severity, child age at referral, and family mobility) had on the BLLs of referred children.  Cases from the LSC were divided into three categories: completed, incomplete, and never-opened cases.  Separate tables were created with MS Access for the case types as well as for the siblings of enrolled children. 

Initial analyses displayed a disappointingly slow decrease in BLLs for all case types, suggesting that my original understanding of how quickly lead is eliminated from a child was optimistic.  A literature review revealed that the half-life of blood lead varies according to several factors (such as exposure change, peak BLL, nutritional status, pharmacokinetic processes, and age) and can take over 20 months in a child with a starting BLL greater than 15 µg/dL[1].  Another study estimated the decrease in a child’s BLL one year after intervention at 25%, with 16% directly attributed to intervention[2].   

Theses studies have set the boundaries of what I expect to observe from my research.  On one hand, I expect the long decay time of blood lead to limit observed improvements in BLLs, yielding closer to a quarter-life rather than a half-life one year after referral.  I also expect variations in BLL reductions, according to the referral BLL severity and the length of exposure.  On the other hand, if the LSC’s interventions are successful in eliminating exposure to lead, I should observe a greater percent decrease in the BLLs of children who have completed case management versus those who have dropped out or never enrolled in the LSC program. 

According to my analyses, the completed cases had a greater average percent decrease in BLLs six to twelve months after referral compared to the incomplete and never-opened cases- 41.4% for the completed cases, versus 33.5% and 33.3% for the incomplete and never-opened cases, respectively.  In addition, both the completed and incomplete cases groups showed a significant decrease in the mean BLL 30 days after referral to the LSC, whereas the never-opened cases did not.  Although the percent of children testing at or above 20 µg/dL (significantly poisoned) 150 to 180 days[3] after the referral varies slightly across case types (39.4% completed, 44.7% incomplete, and 30.3% never-opened), it never dropped below 30% for any of the cases.  As length of case increases to 330 to 360 days past the referral, the number of children testing above 20 µg/dL is reduced slightly in all case types- 33.3% completed, 42.1% incomplete, and 22.2% never-opened. 

All cases under 270 days in length show significant reductions from the referral BLL, but remain open long after this initial change.  The length of the case tends to be dependent on the initial referral BLL- the higher the BLL, the longer the case usually remains open.  Cases with referral BLLs greater than 20 µg/dL achieve the greatest reduction from the referral level, but BLLs in this group remain much higher than those of lower BLL severity groups.  Also, the higher the BLL severity at the referral, the more likely the child was to experience increases in BLL after the close of the case.  However, as other researchers have shown, the amount of BLL reduction after intervention depends heavily on the peak BLL, as well as the duration and frequency of exposure[4].  Residence relocation during the course of the case had the greatest impact in the first 90 days of the case and in general these cases took longer to demonstrate BLL reductions. 

Surprisingly, the percent of LSC cases where caregivers refused an environmental lead inspection (13.3%) was nearly twice the statewide refusal rate (6.7%).  Also, a greater percent of LSC addresses (7.4%) were involved in multiple inspections than addresses for the entire state (5.7%).  Of the 1,025 primary addresses in the LSC’s database, 13% (N=137) were associated with more than one poisoning leading to a referral to the center.  Of the 115 children referred to the LSC more than once, 65% (N=75) were re-poisoned in the same house.  The fact that the number of children multipily referred to the LSC did not vary across case types, suggests that program completion does not prevent future poisonings.

My research demonstrates that once a child is poisoned, a significant amount of time is required to reduce BLLs to below the level of concern, even when case management assistance is provided.  The long half-life of blood lead, which leads to lengthy decay times (even when exposure is eliminated), indicate the difficulty in successfully reducing BLLs after a child has been poisoned.  In the absence of preventative measures, case management programs such as the LSC play an interim role in reducing the BLLs of poisoned children, but the ultimate goal of primary prevention must be realized. 

It is important to review the limitations of the study in order to assess the implications of the results.  A key issue is the use of BLLs as a measure of program success.  To date, BLLs provide the most accessible quantitative calculation, but their use is limited by potentially confounding factors.  Age, seasonality, lifestyle variation (such as cleaning techniques and diet), and client responsibility are important factors that were not controlled for in this study, so their effect is unknown.  In addition, human error in data entry and data manipulation is possible.  Several inconsistencies in the LSC’s database, especially involving incomplete data, may have impacted the results. 

I have made several recommendations to the LSC, which focus on database design and data entry modification, as well as case management.  To increase the efficiency of the program, the LSC should consider modifying their database to allow caseworkers to identify problematic cases (such as repeat referrals) more easily.  It is also necessary that case workers understand all database field options and use them consistently to prevent future entry errors.  Because the most significant BLL reductions occurred in the few months following the referral, the educational component of case management should be most intensive in the first two months of the case.  The importance of follow-up lead tests and preventative practices should be stressed repeatedly in order to decrease the rate of re-poisoning.  The LSC should attempt to communicate with the Rhode Island Department of Human Services (DHS) regarding revisions to the current funding system.  Reorganization of the funding mechanism to allocate resources over a two-year period would allow for the normal decay of blood lead.   Also, the LSC should implement a thorough evaluation of the family at the two-year mark to identify what information was retained and what should be repeated in the future.  If implemented, these recommendations may increase the overall effectiveness of the LSC but the only guaranteed method is a shift towards primary prevention.

It is clear that Rhode Island’s strategy for lead poisoning does not address the root problem of removing the lead hazards.  The prospects of success for a case management service, like the LSC’s program for remediating lead poisoning, is drastically limited by the failure of Rhode Island’s programs for lead-safe housing.  Unless all environmental lead hazards are eliminated from residences, children will continue to be poisoned.  As my results have shown, once a child is poisoned, there is no quick way (even with case management) to reduce BLLs to safe levels.  Therefore, it is imperative that Rhode Island shifts its lead poisoning approach to primary prevention to avoid initial exposure.  The welfare of Rhode Island’s children relies on eliminating all sources of lead from buildings and soil to finally put a halt to an entirely preventable epidemic.