2024-30401. Lead Wheel Weights; Petition for Rulemaking Under the Toxic Substances Control Act (TSCA); Decision Not To Proceed With a Rulemaking

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Environmental Protection Agency

1. 40 CFR Chapter I
2. [EPA-HQ-OPPT-2024-0085; FRL-5398-06-OCSPP]
3. RIN 2070-AJ64

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Petition; reasons for Agency response.

SUMMARY:

The Environmental Protection Agency (EPA or Agency) has decided not to proceed with the development of a regulation addressing the manufacture, processing, or distribution in commerce of lead for wheel-balancing weights (“lead wheel weights”) under the Toxic Substances Control Act (TSCA). This action relates to a citizen petition filed with the Agency in 2009 (“2009 petition”). The 2009 petition, which EPA granted, asked EPA to initiate a rulemaking proceeding to regulate the manufacturing, processing, or distribution in commerce of lead wheel weights. In 2023, the same parties filed a petition for a writ of mandamus (“mandamus petition”) that sought to compel EPA to initiate the rulemaking proceeding requested in the 2009 petition. After reviewing the information submitted in response to an advance notice of proposed rulemaking (ANPRM) issued in April 2024 and EPA's technical analysis thereof, EPA has decided not to proceed with the development of a proposed rule. Addressing potential remaining exposures from lead continues to be a high priority for EPA, as reflected in EPA's announcement that “Lead and Lead Compounds” is on its list of candidate chemical substances currently being considered for future prioritization actions under TSCA.

DATES:

This decision is effective December 23, 2024.

ADDRESSES:

The docket for this action, identified by docket identification (ID) number EPA-HQ-OPPT-2024-0085, is available online at https://www.regulations.gov. Additional information about dockets generally, along with instructions for visiting the docket in-person, is available at https://www.epa.gov/​dockets.

FOR FURTHER INFORMATION CONTACT:

Technical information: Sean Duenser, Existing Chemicals Risk Management Division (7404M), Office of Pollution Prevention and Toxics, Environmental Protection Agency, 1200 Pennsylvania Ave. NW, Washington, DC 20460-0001; telephone number: [phone]; email address: [e-mail].

General information: The TSCA Hotline, ABVI-Goodwill, 422 South Clinton Ave., Rochester, NY 14620; email address: [e-mail].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this action apply to me?

This action is directed to the public in general. It may be of interest to those who manufacture, process, distribute in commerce, use, or dispose of lead wheel weights, or their substitutes. The following list of North American Industrial Classification System (NAICS) codes is not intended to be exhaustive, but rather provides a guide to help readers determine whether this document applies to them. Potentially affected entities may include:

• Primary Smelting and Refining of Nonferrous Metal (except Copper and Aluminum) (NAICS code 331419);
• Secondary Smelting, Refining, and Alloying of Nonferrous Metal (except Copper and Aluminum) (NAICS code 331492);
• Lead die-castings, unfinished, manufacturing (NAICS code 331523);
• Lead die-castings, unfinished, manufacturing (NAICS code 331523); ( print page 104487)
• Automobile Manufacturing (NAICS code 336111);
• Light Truck and Utility Vehicle Manufacturing (NAICS code 336112);
• Heavy Duty Truck Manufacturing (NAICS code 336120);
• All Other Motor Vehicles Parts Manufacturing (NAICS code 336399);
• Motorcycle, Bicycle, and Parts Manufacturing (NAICS code 336991);
• Automobile and Other Motor Vehicle Merchant Wholesalers (NAICS code 423110);
• Motor Vehicle Supplies and New Parts Merchant Wholesalers (NAICS code 423120);
• Tire and Tube Merchant Wholesalers (NAICS code 423130);
• Motor Vehicle Parts (Used) Merchant Wholesalers (NAICS code 423140);
• New Car Dealers (NAICS code 441110);
• Used Car Dealers (NAICS code 441120);
• Recreational Vehicle Dealers (NAICS code 441210);
• Motorcycle, Boat, and Other Motor Vehicle Dealers (NAICS code 441220);
• Automotive Parts and Accessories Stores (NAICS code 441310);
• Tire Dealers (NAICS code 441320);
• General Automotive Repair (NAICS code 811111);
• Other Automotive Mechanical and Electrical Repair and Maintenance (NAICS code 811118);
• Automotive Oil Change and Lubrication Shops (NAICS code 811191); and
• All Other Automotive Repair and Maintenance (NAICS code 811198).

If you have any questions regarding the applicability of this action, please consult the technical information contact listed under FOR FURTHER INFORMATION CONTACT .

B. What is the Agency's authority for taking this action?

TSCA section 21, 15 U.S.C. 2620, allows citizens to petition EPA to initiate a rulemaking proceeding for the issuance, amendment, or repeal of a rule under TSCA sections 4, 6, or 8 or an order under TSCA sections 4 or 5(e) through (f). If EPA grants such a petition, the Agency must promptly commence an appropriate proceeding. In addition, under TSCA section 6(a), if EPA determines that the manufacture, processing, distribution in commerce, use, or disposal of a chemical substance presents an unreasonable risk to human health or the environment, it must “apply one or more of the [TSCA section 6(a)] requirements . . . to the extent necessary so that the chemical substance . . . no longer presents such risk,” which may range from prohibiting or otherwise restricting the manufacturing, processing, or distribution in commerce of the chemical substance (or a particular use), to commercial use requirements or disposal restrictions, to labeling and recordkeeping, among other requirements.

C. What action is the Agency taking?

EPA is issuing this action to inform the public of its decision not to regulate the manufacture, processing, or distribution in commerce of lead for wheel-balancing weights (“lead wheel weights”) under TSCA. This action is limited to lead for lead wheel weights. EPA's actions to address “lead and lead compounds” more broadly are discussed in Unit IV.C. This action relates to a citizen petition filed with the Agency in 2009 under TSCA section 21, which asked EPA to initiate a TSCA rulemaking proceeding to regulate the manufacturing, processing, or distribution in commerce of lead wheel weights (Ref. 1). The 2009 petition was filed by representatives of the following groups: Ecology Center, Sierra Club, Alliance for Healthy Homes, Center for Environmental Health, Environmental Health Watch, Coalition to End Childhood Lead Poisoning, United Parents Against Lead, Louisiana ACORN, Lead Technicians, Tulane University, Drexel School of Public Health, and one individual (collectively, “Petitioners”). EPA granted this petition in 2009. In 2023, the same parties filed a petition for a writ of mandamus (“mandamus petition”) in the United States Court of Appeals for the Ninth Circuit: Ecology Center, et al. v. U.S. EPA, No. 23-70158 (9th Cir.) (Ref. 2). The mandamus petition sought to compel EPA to initiate the rulemaking proceeding requested in the 2009 petition. EPA published for comment a proposed settlement agreement with the petitioners in March 2024. As part of the settlement agreement, EPA proceeded with an ANPRM in April 2024. EPA and the Petitioners then entered into a settlement agreement in September 2024.

EPA is taking this action after reviewing the information submitted to EPA in response to the ANPRM (Ref. 3), in addition to other reasonably available information, and this action is also supported by EPA's technical analysis, entitled: Technical Support Document for Lead Wheel Weights (TSD) (Ref. 4), which further discusses the low potential for exposure to children and injury to human health or the environment from lead wheel weights based on the exposure scenarios evaluated for this petition.

This action serves as EPA's final decision in response to the 2009 petition. In addition, this action will not have a preemptive effect on State actions under TSCA section 18.

D. Why is the Agency taking this action?

In April 2024, EPA published an ANPRM seeking information regarding the use and exposure to lead from the manufacture (including import), processing (including recycling), distribution in commerce, use, and disposal of lead wheel weights, as well as information on their substitutes, to help determine if there is unreasonable risk to human health and the environment associated with lead wheel weights (Ref. 3). The Agency received 128 comments providing input on whether to move forward with the development of a rule regulating lead wheel weights. The Agency did not, however, receive any lead wheel weight exposure data during the ANPRM public comment period that it had not already considered or that would be sufficient to determine that this activity presents an unreasonable risk of injury to health or the environment and necessitate a proposed rulemaking, as discussed in Unit IV. As also addressed in Unit IV., the Agency preliminarily found that risk associated with residential exposure is lower than previously believed. The Agency further believes that examination of risks associated with exposures to lead from the manufacture (including import), processing (including recycling), distribution in commerce, use, and disposal of lead wheel weights would be more appropriately assessed and addressed as part of a broader assessment of exposures associated with lead and lead compounds during a complete TSCA section 6(b) risk evaluation. Therefore, EPA is not proceeding with a proposed regulation addressing lead wheel weights.

II. Background

A. Overview of Lead Wheel Weights

Wheel weights are small pieces of metal or other material used to correct imbalances in the weight distribution of motor vehicle tires. Lead has historically been a primary component of many wheel weights because of its malleability, high density, and relatively low cost. Nine States in the United States have banned the sale, distribution, and/or use of lead wheel weights. In addition, many automotive manufacturers, both those manufacturing within the United States ( print page 104488) and those exporting vehicles to the United States, have switched to alternative wheel weight options in new vehicle production that meet the regulatory requirements in those states, citing the impracticality of using different wheel weights for new vehicles sold only in those States, due to the interstate and international nature of automotive production (Ref. 5). For the same reasons, most automotive manufacturers that sell vehicles in the United States are in compliance with Canada's prohibition on the use of lead wheel weights as well (Ref. 5). However, lead wheel weights may still be used for wheel balancing in auto repair and maintenance of vehicles post-sale. EPA identified one remaining domestic manufacturer of lead wheel weights in the United States and EPA has identified multiple importers of lead wheel weights (Ref. 6). Wheel weights can separate from the wheel due to failure of the adhesive or clip attaching them, or due to impact of the wheel with a pothole or road debris, during a crash, or due to other physical strains. Lead wheel weights that separate from vehicle wheels, or are not properly disposed of, may be abraded into fine particles by traffic. Abraded lead particles may then be released into the air as part of roadway dust due to turbulence from wind or from passing vehicles. As this lead migrates to nearby homes, it can enter the yard soil or the indoor dust. Children or adults living nearby can be exposed through ingestion of soil or dust particles. Lead wheel weights may also enter the environment by washing off roads during rain, being thrown from the road intact by vehicles, or by being collected by street cleaners and disposed of in landfills. Exposure scenarios identified by Petitioners are addressed further in the TSD (Ref. 4).

B. Overview of Petitioners Request

1. 2009 Petition

In May 2009, Petitioners submitted a TSCA section 21 petition requesting that EPA “establish regulations prohibiting the manufacture, processing, and distribution in commerce of lead wheel balancing weights (`wheel weights')” (Ref. 1). Petitioners raised concerns that lead wheel weights result in pervasive lead exposure to children and health effects on ecological receptors. EPA requested public comment on the petition in July 2009 (Ref. 7) and granted the petition on August 26, 2009 (Ref. 8). EPA stated in its letter granting the petition, “[t]he Agency will promptly commence an appropriate proceeding under TSCA. EPA anticipates commencing this proceeding through either an Advance Notice of Proposed Rulemaking or a Proposed Rule” (Ref. 8).

2. 2023 Petition for Writ of Mandamus

In August 2023, the same Petitioners sought a writ of mandamus in the United States Court of Appeals for the Ninth Circuit and asked the court to direct EPA to conclude the rulemaking Petitioners requested in the 2009 petition. EPA and Petitioners subsequently entered the Ninth Circuit Mediation Program. A joint motion to dismiss the petition for writ of mandamus was filed and granted. EPA was required to either (1) sign a proposed rule and request publication by the Office of the Federal Register, or (2) request publication in the Federal Register of a determination not to proceed with regulating lead wheel weights.

3. What support did the petitioners offer?

In the 2009 petition, Petitioners highlighted that automobiles are a significant contributor to ongoing lead releases to the environment and identified lead wheel weight failures as one of the largest ongoing releases of lead to the environment (Ref. 1). Petitioners cited research from the New Jersey Department of Environmental Protection finding that high concentrations of environmental lead are directly correlated with traffic volume. Petitioners also claimed that the voluntary National Lead-Free Wheel Weight Initiative (NLFWWI) falls short of what is needed to protect children, the public, and the environment given EPA acknowledged that 1.6 million pounds of lead is lost when wheel weights fall off during normal driving conditions.

EPA granted the 2009 petition on August 26, 2009. In the 2023 mandamus petition, the Petitioners provided discussion on the danger posed by lead, stating that lead is a toxic heavy metal for which there is no safe level of exposure, citing EPA's own Integrated Science Assessment for Lead from 2013 (Ref. 9), and the Reconsideration of the Dust-Lead Hazard Standards and Dust-Lead Post Abatement Clearance Levels proposed rule (Ref. 10). Petitioners also discussed the impacts on human health and the environment related to lead exposures, stressing that children are at particularly high risk of harm from lead exposure (Ref. 2). Specifically, Petitioners noted that children experiencing disproportionate impacts due to racial and socioeconomic disparities are at high risk of harm. Petitioners also noted that lead causes detrimental environmental effects to fish and wildlife (Ref. 2). Petitioners raised that lead from lead wheel weights is one pathway of exposure to humans, claiming that lead wheel weights enter the environment, and ultimately people's bodies when they are dislodged from vehicles, despite the availability of safer, lead-free, wheel weight alternatives in the market (Ref. 2). Petitioners also provided comment and numerous studies in response to the ANPRM; however, no new information that could be used to inform exposure to lead wheel weights was identified in the comments.

C. Overview of the 2024 ANPRM

In order for EPA to consider lead wheel weight regulation under TSCA section 6(a), the agency needs technical data linking lead wheel weight exposure to effects on human health and the environment in order to inform whether lead wheel weights pose unreasonable risk. EPA issued an ANPRM on April 3, 2024, requesting comment and information from the public and all stakeholders on the use and exposure to lead from the manufacture (including import), processing, distribution in commerce, use, and disposal of lead wheel weights, as well as information on their substitutes (Ref. 3). EPA received 21,297 comments, of which 128 were posted to the docket, including 8 unique comments from Petitioners; mass mailers; comments from the recycling, metal, and automotive industries; and a scientific organization (Ref. 11). The Agency did not receive additional data in response to the ANPRM that could be used in its technical analysis to support a proposed rulemaking.

1. ANPRM Comment Summary

The following is a summary of comments received on EPA's ANPRM for lead wheel weights (Ref. 3). This is intended to serve as a summary, rather than an opportunity for EPA to respond to each individual comment.

a. Lead Wheel Weight Effects on Human Health and the Environment

Petitioners and advocacy groups support regulatory action for lead wheel weights based on the rationale that this would protect children's health (Ref. 12). Petitioners stated that fallen lead wheel weights can lead to potential exposures to children and adults who inhale or ingest roadway particles containing lead from wheel weights or who drink contaminated water (Ref. 12). They commented that even very low blood lead levels are associated with ( print page 104489) neurodevelopmental harm with irreversible effects in children and increased risks of cardiovascular disease in adults (Ref. 12). Another commenter stated that scientists now recognize that lead does lasting harm to children even at extremely low exposure levels. The commenter cited the 2012 National Toxicology Program conclusion that blood lead concentrations below 5 µg/dL have adverse effects on academic achievement, IQ, and attention-related behaviors (Ref. 13).

The commenter added that people from backgrounds with socioeconomic disparities live closer to transportation roadways and are more vulnerable to exposure to lead wheel weights that have fallen from vehicles. The commenter stated that exposure to lead from the degraded wheel weights can occur in a variety of ways, including from pedestrians in urban areas (and their pets) stepping on dust from lead wheel weights in city streets and tracking the lead dust into their homes (Ref. 13). The commenter also noted that it is known that blood lead levels correlate with transportation corridors (both in and outside of urban centers) and lead wheel weights contribute to those transportation-related exposures. The commenter raised the concern that there is growing evidence that the adverse effects of lead are most severe in Black and Hispanic children and children in low-income households. The commenter contended that this suggests that socioeconomic disadvantages can worsen the impact of lead exposures (Ref. 13).

b. Safer Wheel Weight Alternatives and Voluntary Programs

Petitioners also commented that there are widely available, economically viable alternatives to lead wheel weights (Ref. 12). Another commenter noted that industry has largely shifted into using zinc or steel alloy wheel weights (Ref. 5). The commenter continued to discuss that lead content in wheel weights has been reduced from the over 90% associated with high-density lead wheel weights to the current 0.1% associated with current weights as mandated by multiple State and international standards. EPA's voluntary NLFWWI, combined with the actions taken by the States, has resulted in the voluntary removal of all but trace amounts of lead in wheel weights used in new vehicles manufactured by NLFWWI members. The commenter stated that this approach appears to have mitigated the potential for unreasonable risk to human health or the environment (Ref. 5).

c. State Bans on Lead Wheel Weights

Petitioners are seeking a nationwide ban on lead wheel weights to streamline regulations and certainty across the United States. In their comments, Petitioners noted that even though there are existing lead wheel weight bans in nine States, Petitioners believe Federal action is required since they claim State bans are incomplete. For example, it is possible to live in a State where lead wheel weights are banned, such as Maine, and purchase lead wheel weights from online retailers such as eBay (Ref. 12). All State bans took place after the 2009 petition was granted. Another commenter, a trade association representing the auto industry, countered this assertion by stating that, given the interstate and international nature of auto production, it would be impractical to use different wheel weights for new vehicles sold in only those nine States. Consequently, the commenter noted, all of the automobile manufacturers in the trade association have switched to alternative wheel weight options in new vehicle production that meet the requirements of these State regulations (Ref. 5). The commenter extended this rationale internationally to Canada, where the country prohibited the “manufacturing or importing wheel weights containing more than 0.1% lead by weight,” in February 2024 (Ref. 14). The commenter noted that, for the same reasons, the original equipment manufacturer members that sell vehicles in the United States are in compliance with Canada's prohibition on the use of lead wheel weights (Ref. 5).

d. Federal Regulations on Lead Wheel Weight Recycling Already Exist

One commenter expressed concerns about lead from wheel weights entering a metal scrap stream. The commenter feared that if the lead wheel weights are not removed prior to the shredding and crushing process, they become nearly impossible to locate within the scrap stream and will be melted in an electric arc furnace (EAF) (Ref. 15). However, another commenter believed existing regulations suffice, asserting that regulations for certain EAFs and iron and steel foundries under the Clean Air Act (CAA) effectively require removal of lead wheel weights from end-of-life vehicles (ELVs) by automotive dismantlers and metal shredding facilities. The commenter cited existing Federal regulations such as the CAA regulations under 40 CFR part 63, subparts EEEEE (Iron and Steel Foundries), YYYYY (Electric Arc Furnace Area Sources), and ZZZZZ (Iron and Steel Foundries Area Sources), which include requirements for these EAFs and foundries to minimize, to the extent practicable, the presence of lead and lead containing components in the input ferrous materials supplied to them (Ref. 16).

e. Economic Value and Obligations To Remove Lead Wheel Weights During Recovery and Recycling

Multiple commenters also raised the economic value of recovering lead wheel weights at the recycling stage. One commenter mentioned that these recycling facilities are heavily regulated under Federal environmental statutes. The commenter believed that this ensures that recycling facilities have not just a legal obligation to properly manage any lead wheel weights, but also appropriate financial assurance for the future (Ref. 17). Another commenter provided an example of economic value to the recycling sector, commenting that lead wheel weights are easily accessible on the wheels of ELVs and are relatively valuable, especially as a recycled material that meets the “ropes” specification. The commenter believed that the low cost of removing lead wheel weights from the wheels of ELVs combined with their higher value provides economic incentive to remove them from ELVs as soon as possible (before further dismantling or shredding). Such removal of lead wheel weights prior to ELV shredding also provides operational benefits at the metal shredding facility ( e.g., higher quality of produced recycled ferrous metal and recycled nonferrous metals) (Ref. 16).

2. Additional Industry and Stakeholder Engagement

In addition to issuing the ANPRM, EPA conducted outreach to various stakeholders in the lead wheel weight industry. EPA identified one remaining lead wheel weight manufacturer in the United States; other manufacturers that had previously manufactured lead wheel weights confirmed their transition to lead-free alternatives, such as steel and zinc alloy wheel weights, citing the bans of lead wheel weights in nine States. During discussions with the sole remaining manufacturer and other stakeholders, as well as review of comments to the ANPRM, EPA learned that lead wheel weight products are increasingly being imported into the United States rather than manufactured domestically. EPA requested exposure data from the manufacturer and did not receive any. The Alliance for Automotive Innovation, which represents automakers that produce and ( print page 104490) sell approximately 95 percent of the new light-duty vehicles in the United States, commented that they surveyed their members and found that none of their original-equipment manufacturers use lead wheel weights on new vehicles manufactured or distributed to dealerships in the United States (Ref. 5).

III. Analysis of Exposure Pathways

A. Children's Roadside Exposure

EPA analyzed the potential exposure pathway of residential exposure to children from lead-containing road dust from lead wheel weights. IQ loss in children is considered the most sensitive endpoint for lead exposure. This quantitative exposure analysis simulated the scenario for exposure from this pathway (a residence at the intersection of two busy roads) and estimated the blood lead levels and IQ decrement in children up to age 7 that could result from exposure to lead dust created by abraded lead wheel weights that could be tracked-in with yard soil or blown into a household where children could be exposed (Ref. 4). This analysis found low risk to children from this pathway based on the information and data available. The increase in residential soil and dust lead concentration due to lead wheel weights, even in the near-roadway scenario, is small compared with other sources that contribute to lead concentration. Soil and dust lead concentrations from lead wheel weights, along with residential background soil and dust lead concentrations taken from the American Healthy Homes Surveys (AHHS I and II), are presented in table 4-8 of the Technical Support Document (Ref. 4). The baseline concentrations of lead in residential soil and dust from the AHHS used in this analysis were 100.06 μg/g and 79.16 μg/g respectively, and lead wheel weights contributed an additional 3.02 μg/g and 1.15 μg/g respectively in the near-roadway scenario. The small contribution of lead wheel weights to residential lead concentrations leads to small potential impacts on BLL and IQ loss. The approximate wheel weight contribution to IQ point decrement was estimated to be 0.026 IQ points at the higher-end of predicted soil and dust exposure, which corresponded to a 2-year-old child living near a busy road intersection. By comparison, the estimated IQ decrement for a 2-year-old child in the corresponding baseline scenario from residential background concentrations of lead in soil and dust was 2.61 IQ points (see table 5-2 in the Technical Support Document (Ref.4)). This means that the estimated IQ decrement from residential background concentrations of lead in soil and dust are over 100 times higher than those expected from lead wheel weight exposure for a 2-year-old child in the near-roadway scenario.

In the children's roadside exposure scenario, lead wheel weights are lost from cars onto the road. Lost wheel weights are abraded over time due to weathering and further traffic abrasion. Some of the lead that is abraded will be emitted to the air as part of roadway dust due to roadway turbulence and other dust emission mechanisms. EPA estimated the road dust from lead wheel weights, accounting for the following parameters: loss rate of lead wheel weights, fraction of weights degraded per day, street cleaning frequency, additional wheel weight removal rate, additional dust loss rate, and emission rate. EPA used a similar model to characterize deposition to soil resulting from airborne lead particles emitted from the road, which computed the steady State amount of lead in the air as a function of distance away from the road. This model accounted for particle deposition rate, height of the air compartment, and wind speed. For its yard soil module, EPA predicted the yard lead concentrations in a receptor yard near the roadway, downwind from the road, which accounted for soil depth, half-life of lead in soil, dimensions of the yard, and accumulation time. Further modeling estimated the contribution of lead in yard soil from lead wheel weights to indoor dust lead concentrations in the residence. Each of these model parameters is subject to uncertainty, and, while EPA attempted to make conservative assumptions, when possible, not all exposure scenarios could be accounted for. For details of the assumptions made in estimating children's exposure to lead from lead wheel weights, please see the accompanying Technical Support Document (Ref. 4).

EPA determined the effect of lead wheel weights on a hypothetical child's blood lead level using peer-reviewed models and literature wherever possible, using approaches and input values similar to those used in other EPA lead analyses. EPA's blood lead module used the lead soil, air, and dust concentrations as calculated above as inputs to the All Ages Lead Model (AALM) version 3.0, an EPA-developed exposure model of lead across a lifetime. Using this model, blood lead levels were estimated each year at ages 1 through 7. The results show a low impact of the exposure to lead wheel weights on blood lead levels through the first seven years of a child's life. Estimated exposure to lead wheel weights contributed to an increase of blood lead levels of 0.012 μg/dL at the higher end of the predicted exposure. That estimate means the contribution of lead exposure from lead wheel weights led to a less than 1% estimated increase in blood lead levels. Additionally, EPA calculated IQ decrements for children exposed to lead wheel weights in the children's roadside exposure scenario. The effects of lead wheel weights on lifetime IQ loss were estimated to be small (0.026 IQ points at the higher-end of predicted exposure) for the near-roadway soil and dust exposure scenario, and because IQ loss in children is considered the most sensitive endpoint for lead exposure, other health effects of near-roadway lead wheel weight exposure in children and adults were not evaluated, but are expected to be small as well.

B. Ecological Screening Assessment

EPA considered lead wheel weights that are lost from cars and deposited into streams or freshwater lakes via rainfall by modeling a short-term exposure scenario and a long-term exposure scenario. In the short-term exposure scenario, a hypothetical 1-mile roadway drains directly into a stream after a 1-day rainfall event. The rate of lead wheel weight loss from cars on all modeled roads in the water deposition scenario was set to the highest value available in the scientific literature, representing a busy six-lane road in Albuquerque, New Mexico (Ref. 18) and corresponding to approximately five hundred 1-ounce lead wheel weights lost per mile of roadway per year. EPA expects that this assumption is an overestimate, as most roads are not six-lane highways and because current rates of lead wheel weight use are expected to be lower than in 2000, when the Albuquerque loss rate study (Ref. 18) was published. Nine U.S. States have banned lead wheel weights since this loss rate study was conducted, and an industry group representing the manufacturers of approximately 95 percent of new cars sold in the United States currently indicates that these manufacturers no longer use lead wheel weights on new vehicles (Ref. 5). Aquatic organisms in streams and lakes can be exposed to lead through this route. EPA's assessment of this scenario estimates the lead concentration in water attributable to lead wheel weights that dissolve in streams and lakes. It considers a 1-day rainfall event and long-term accumulation of lead wheel weights in freshwater bodies.

This assessment accounted for the following parameters: wheel weight loss ( print page 104491) rate, street cleaning frequency, flow rate of stormwater-receiving streams, fraction of lead wheel weights that dissolve during each rainfall event, and water concentrations. EPA assumed that all lead wheel weights present on the roadway were washed into the stream, that no rainfall event had occurred since the street was last cleaned, and that the maximum time had elapsed between street cleaning events (6 months). These assumptions corresponded to slightly more than 257 1-ounce lead wheel weights simulated to enter the 1-mile stretch of stream. EPA estimated lead concentrations for varying values of streamflow and dissolution rates of lead in a 1-day rainfall scenario. The maximum water concentration attributable to lead wheel weights due to a 1-day rainfall event is 0.0000164 μg/L (less than 0.1 parts per trillion), which occurs when 100% of a lead wheel weight dissolves per year (the fastest dissolution rate modeled), there are only two rainfall events per year, each immediately preceding the street cleaning event (leading to the maximum possible accumulation of lead wheel weights), and the stream flow rate is 50 cubic feet per second (the smallest stream modeled). By comparison, the level of concern for acute freshwater aquatic exposure to lead in water is 65 μg/L (Ref. 19). Therefore, under the most conservative conditions modeled (a fast dissolution rate for lead wheel weights, and a small stream containing a low volume of water in which to dilute the wheel weights' lead contribution), the estimated water concentration of lead attributable to wheel weights remains far below the level of concern for acute toxicity in freshwater organisms. The slow dissolution rate of lead wheel weights and the relative insolubility of inorganic lead in water means that the estimated acute exposure to lead in freshwater streams due to lead wheel weights (0.0000164 μg/L) is far below the acute level of concern for aquatic life (65 μg/L), indicating that acute toxicity to freshwater organisms from lead wheel weights is unlikely based on this analysis.

EPA also considered a long-term ecological exposure scenario. Depending on certain conditions ( e.g., water acidity), lead wheel weights that have been swept up by rainfall and deposited in freshwater ponds and lakes can dissolve over time, increasing the lead water concentration. EPA's analysis of this scenario considers the average contribution of lead wheel weights to freshwater lead concentration on a national scale. The model was based on determining the accumulated mass of wheel weights in water, the rate at which they dissolve, the volume of water, and the rate at which fresh water is replaced by rainfall. This analysis determined that the highest estimated lead concentration in water was 0.0009 μg/L (less than 1 part per trillion), which is below the criterion continuous concentration (CCC) hazard level for freshwater aquatic life, which ranges from 1.3 to 7.7 μg/L depending on water hardness with a default value at 2.5 μg/L (corresponding to 100 mg/L hardness as CaCO₃). This estimate included the assumption that 100 percent of lost lead wheel weights are deposited in water bodies. Therefore, actual average lead concentrations in the environment due to lead wheel weights are likely lower, although limitations in the analysis due to the national scale of the long-term ecological exposure scenario means that individual water bodies may experience different contributions of lead from lead wheel weights depending on their location relative to roads. For further details on the technical analyses conducted in support of this action, please see the accompanying Technical Support Document.

IV. Decision Not To Proceed With Rulemaking

A. EPA's Analysis Estimates Low Impacts to Children and the Environment From Exposure to Lead Wheel Weights

Children exposed to lead are at an increased risk of adverse health effects, including decreased cognitive performance, greater incidence of problem behaviors, and increased diagnoses of attention-related behavioral problems. The negative health effects associated with lead exposure are well-documented, and include neurological, cardiovascular, renal, reproductive, developmental, and hematological effects (Ref. 20). Several studies have demonstrated a link between increased blood lead level (BLL) and IQ loss in children (Ref. 21 and Ref. 22). IQ loss is among the most sensitive endpoints studied ( i.e., IQ loss occurs at a lower BLL than other health effects and therefore IQ loss is used as a reference for lead's adverse health effects in children). EPA calculated IQ decrements for children exposed to lead from lead wheel weights in a near-roadway scenario, where lead is released into the roadway environment due to abrasion of lost wheel weights, the lead migrates to the air surrounding the home, the deposition of lead particles contributes to yard soil concentrations, and outdoor soil lead levels influence the indoor dust lead levels in the residence (Ref. 4). The effects of lead wheel weights on lifetime IQ loss were estimated to be low for the near-roadway soil and dust scenario. At ages 2 and 7, lifetime IQ loss models with conservative assumptions found the contribution of lead wheel weights to result in an estimated difference in lifetime IQ loss of 0.026 points for this exposure scenario. This means that near-roadway soil and dust exposure from abraded lead wheel weights added approximately 1 percent to the IQ loss already attributable to exposure to other sources of lead.

Lead exposure can also cause adverse effects in animals and plants in the environment (Ref. 20). EPA estimated water concentrations in streams and water bodies attributable to lead wheel weights lost from vehicles and compared them to the freshwater levels of concern published in the Ambient Water Quality Criteria for Lead (Ref. 19). These levels of concern represent acute and chronic lead concentrations in freshwater that EPA considers harmful to wildlife. In the acute (short-term) and chronic (long-term) scenario, EPA's analysis estimated that the concentration of lead in freshwater streams and water bodies attributable to lead wheel weights was less than 1 part per trillion. By comparison, the freshwater levels of concern are 65 parts per billion for acute exposure, and 2.5 parts per billion for chronic exposure. The estimated lead exposure of wildlife in freshwater due to lead wheel weights is several orders of magnitude lower than the acute and chronic levels of concern, indicating low potential for adverse effects. See EPA's TSD for more information (Ref. 4).

In addition to the conclusions made in EPA's analysis, the Agency did not receive, during its engagement with stakeholders and with the sole remaining domestic lead wheel weight manufacturer, or during the 30-day public comment period for the ANPRM, additional data that could be used in the TSD that would support a proposed rulemaking for lead wheel weights. The Agency did receive comment from the Alliance for Automotive Innovation, which represents automakers that produce and sell approximately 95 percent of the new light-duty vehicles in the United States. They surveyed their members and found that none of their original-equipment manufacturers use lead wheel weights on new vehicles manufactured or distributed to dealerships in the United States (Ref. 5).

B. Statutory and Regulatory Context

In the August 2023 mandamus petition (Ref. 2), Petitioners cite EPA's ( print page 104492) proposed rule entitled, “ Reconsideration of the Dust-Lead Hazard Standards and Dust-Lead Post-Abatement Clearance Levels ” (88 FR 50444, August 1, 2023 (FRL-8524-01-OCSPP)) (Ref. 10). Specifically, Petitioners reference EPA's statement: “[T]here is no evidence of a threshold below which there are no harmful health effects from lead exposure.” This is cited to support the petition's discussion on the dangers posed by lead and lead wheel weights and, more specifically, that lead is a dangerous toxic chemical that can cause irreversible health harms at low levels of exposure. Furthermore, the Federal Lead Action Plan, developed by the President's Task Force on Environmental Health Risks and Safety Risks to Children, which comprises 17 Federal departments and offices, including EPA, states that “no safe blood lead level in children has been identified” (Ref. 23).

EPA is reaffirming these positions and continues its commitment to strengthening public health protections, addressing lead contamination for communities with the greatest exposures, and promoting environmental justice. EPA is clarifying in this document that the authorities under Title X of the Housing and Community Development Act of 1992 (also known as the Residential Lead-Based Paint Hazard Reduction Act of 1992 or “Title X”) (Pub. L. 102-550) and TSCA Title IV differ from TSCA section 6.

TSCA Title IV directs EPA to identify the level of dust-lead exposure that “would result in adverse human health effects” as a type of lead-based paint hazard (15 U.S.C. 2681(10)). In addition, on May 14, 2021, the United States Court of Appeals for the Ninth Circuit issued an opinion (2021 Court Opinion) which instructed EPA to consider only health factors when setting the dust-lead hazard standards (described as “dust-lead reportable levels” in EPA's final rule) (89 FR 89416, November 12, 2024 (FRL-8524-02-OCSPP)). On November 12, 2024, EPA published the final rule to lower these standards to “any reportable level as analyzed by a laboratory recognized by EPA's National Lead Laboratory Accreditation Program (NLLAP).” This revision acknowledges the current state of scientific evidence ( i.e., that there is no evidence of a threshold below which there are no harmful effects on cognition from lead exposure) and is consistent with the 2021 Court Opinion. The revised hazard standards are inclusive of any reportable level of dust-lead and do not distinguish based on health risks posed. In the same rule, EPA revised the dust-lead action levels (DLAL, previously known as dust-lead clearance levels), which are the allowable levels of dust-lead loadings on a surface following completion of an abatement activity outlined in the Lead-based Paint Activities Rule (40 CFR 745.83 and 745.223). The revised DLAL are 5 μg/ft² , 40 μg/ft² , and 100 μg/ft² for floors, window sills, and troughs, respectively, and are the levels at which EPA recommends an abatement or other lead hazard control measures. Therefore, under the Lead-based Paint Activities Rule, in instances where reportable dust-lead levels are present ( i.e., a dust-lead hazard), EPA recommends lead hazard control work only when the levels are at or above the DLAL.

Under TSCA section 6(a), “[i]f the Administrator determines in accordance with subsection (b)(4)(A) that the manufacture, processing, distribution in commerce, use or disposal of a chemical substance or mixture, or that any combination of such activities, presents an unreasonable risk of injury to health or the environment, the Administrator shall by rule . . . apply one or more of the [section 6(a)] requirements to such substance or mixture to the extent necessary so that the chemical substance no longer presents such risk.” EPA looks to section 6(b) and its implementing regulations (Ref. 24) when considering whether a chemical substance presents an unreasonable risk. Pursuant to TSCA section 6(b), EPA must decide whether the “chemical substance presents an unreasonable risk of injury to health or the environment, without consideration of costs or other non-risk factors, including an unreasonable risk to potentially exposed or susceptible subpopulations identified as relevant to the risk evaluation by the Administrator, under the conditions of use.” For example, TSCA section 6(b)(4)(F) states: “In conducting a risk evaluation under this subsection, the Administrator shall . . . integrate and assess available information on hazards and exposures for the conditions of use of the chemical substance.” When determining unreasonable risk, the Agency weighs the effects of the chemical substance on health and human exposure under the conditions of use; the effects of the chemical substance on the environment and environmental exposure under the conditions of use; the population exposed (including any potentially exposed or susceptible subpopulations), the severity of hazard (the nature of the hazard, the irreversibility of hazard), and uncertainties.

C. Including Lead and Lead Compounds in the TSCA Prioritization Process

EPA's work to protect children from exposure to lead is ongoing, and reducing childhood lead exposure continues to be a priority for both EPA and the Federal Government (Federal Lead Action Plan) (Ref. 23). There are multiple sources of lead including lead-based paint, lead in drinking water, and lead contaminated dust and soil. As a part of this action, the Agency analyzed the potential risk from lead in the environment as a result of lead from fallen wheel weights, which could in turn contaminate residential soil, residential dust, surface water, and groundwater, as these risks were the focus of the 2009 petition. EPA recognizes there are many other potential sources of lead exposure, including occupational exposure during the production and processing of lead wheel weights. However, EPA believes these exposures would be more appropriately assessed when “Lead and Lead Compounds” are prioritized and a full risk evaluation under TSCA section 6(b) with peer review can be conducted. During this process, EPA will conduct a comprehensive, peer reviewed, risk evaluation to determine whether lead and lead compounds present an unreasonable risk of injury to health, without consideration of costs or other non-risk factors, including an unreasonable risk to potentially exposed or susceptible subpopulations identified. EPA will identify, where relevant, the likely duration, intensity, frequency, and number of exposures to lead and lead compounds under each condition of use for each step in the chemical's life cycle. EPA may also need to develop a peer-reviewed threshold to determine the level of adult health effects that would be considered unreasonable during the risk evaluation process.

EPA has included “Lead and Lead Compounds” on its list of candidate chemical substances currently being considered for future prioritization actions. As described in 40 CFR 702.5(c)(2), EPA is required to ensure that, at any given time, at least 50 percent of TSCA risk evaluations are drawn from the TSCA 2014 Work Plan (Ref. 25). Lead and lead compounds are included in the TSCA 2014 Work Plan, but prioritization and risk evaluation for lead and lead compounds have not yet been initiated (Ref. 26). During a risk evaluation, lead and lead compounds would undergo a 3-year robust and comprehensive review of hazards and exposures and consider the weight of the scientific evidence as required by ( print page 104493) TSCA section 6(b)(4)(F), including peer-review of scientific information, technical procedures, measures, methods, protocols, methodologies, or models used in the evaluation, employed in a manner consistent with the best available science, in accordance with TSCA section 26(h).

V. References

The following is a list of the documents that are specifically referenced in this document. The docket includes these references and other information considered by EPA, including documents that are referenced within the documents that are included in the docket, even if the reference is not physically located in the docket. For assistance in locating these other documents, please consult the technical person listed under FOR FURTHER INFORMATION CONTACT .

1. Ecology Center. TSCA Section 21 Petition Requesting EPA to Establish Regulations Prohibiting the Manufacture, Processing, and Distribution in Commerce of Lead Wheel Balancing Weights. May 28, 2009. https://www.epa.gov/​sites/​default/​files/​2015-10/​documents/​petition4.pdf.

2. United States Court of Appeals for the Ninth Circuit. Petition for Writ of Mandamus. August 22, 2023. https://www.epa.gov/​system/​files/​documents/​2024-01/​petition-for-review.pdf.

3. U.S. EPA. Lead Wheel Weights; Regulatory Investigation Under the Toxic Substances Control Act (TSCA). Federal Register . 89 FR 22972, April 3, 2024 (FRL-5398-05-OCSPP). https://www.govinfo.gov/​content/​pkg/​FR-2024-04-03/​pdf/​2024-06804.pdf.

4. U.S. EPA. Technical Support Document for Lead Wheel Weights. December 2024.

5. Comment submitted by Alliance for Automotive Innovation. May 9, 2024. https://www.regulations.gov/​comment/​EPA-HQ-OPPT-2024-0085-0037.

6. Abt. Memo, Estimated Volume of LWW Imports, Manufacture, and Use. July 23, 2024.

7. U.S. EPA. Lead Wheel Balancing Weights; TSCA Section 21 Petition; Notice of Receipt and Request for Comment. Federal Register . 74 FR 34342, July 15, 2009 (FRL-8424-7). https://www.govinfo.gov/​content/​pkg/​FR-2009-07-15/​pdf/​E9-16815.pdf.

8. U.S. EPA. EPA Response to TSCA Section 21 Petition. August 26, 2009. https://www.epa.gov/​sites/​default/​files/​2015-10/​documents/​document.pdf.

9. U.S. EPA. Integrated Science Assessment for Lead. July 2013. https://assessments.epa.gov/​isa/​document/​&deid%3D255721.

10. U.S. EPA. Proposed rule. Reconsideration of the Dust-Lead Hazard Standards and Dust-Lead Post-Abatement Clearance Levels. Federal Register . 88 FR 50444, August 1, 2023 (FRL-8524-01-OCSPP). https://www.govinfo.gov/​content/​pkg/​FR-2023-08-01/​pdf/​2023-15073.pdf.

11. U.S. EPA. Lead Wheel Weight Docket. https://www.regulations.gov/​docket/​EPA-HQ-OPPT-2024-0085.

12. Comment submitted by Ecology Center et al. May 10, 2024. https://www.regulations.gov/​comment/​EPA-HQ-OPPT-2024-0085-0058.

13. Comment submitted by Project TENDR (Targeting Environmental Neuro-Development Risks), The Arc of the U.S. May 9, 2024. https://www.regulations.gov/​comment/​EPA-HQ-OPPT-2024-0085-0039.

14. Canada Gazette. Prohibition of the Manufacture and Importation of Wheel Weights Containing Lead Regulations. Part II, Volume 157, Number 4. February 3, 2023. https://gazette.gc.ca/​rp-pr/​p2/​2023/​2023-02-15/​html/​sor-dors15-eng.html.

15. Comment submitted by Steel Manufacturers Association (SMA). May 9, 2024. https://www.regulations.gov/​comment/​EPA-HQ-OPPT-2024-0085-0038.

16. Comment submitted by Recycled Materials Association (ReMA). May 9, 2024. https://www.regulations.gov/​comment/​EPA-HQ-OPPT-2024-0085-0041.

17. Comment submitted by Association of Battery Recyclers, Inc. (ABR), Battery Council International (BCI), and International Lead Association (ILA). May 10, 2024. https://www.regulations.gov/​comment/​EPA-HQ-OPPT-2024-0085-0057.

18. Root RA. Lead loading of urban streets by motor vehicle wheel weights. Environ Health Perspect. 2000 Oct;108(10):937-40. doi: 10.1289/ehp.00108937. PMID: 11049812; PMCID: PMC1240125.

19. U.S. EPA. Ambient Water Quality Criteria for Lead—1984. EPA-400/5-84-027. Washington, DC: Office of Water, Regulations and Standards Criteria and Standards Division. January 1985.

20. U.S. EPA. Integrated Science Assessment for Lead. January 2024. https://assessments.epa.gov/​isa/​document/​&deid%3D359536.

21. Lanphear et al. Low-level environmental lead exposure and children's intellectual function: an international pooled analysis. Environ Health Perspect. 2005 Jul;113(7):894-9. doi: 10.1289/ehp.7688.

22. Lanphear et al. Erratum: Low-Level Environmental Lead Exposure and Children's Intellectual Function: An International Pooled Analysis. Environ Health Perspect. 2019 Sep;127(9):99001. doi: 10.1289/EHP5685. PMID: 16002379; PMCID: PMC1257652.

23. President's Task Force on Environmental Health Risks and Safety Risks to Children. 2018. The Federal Action Plan to Reduce Childhood Lead Exposures and Associated Health Impacts. https://ptfcehs.niehs.nih.gov/​sites/​niehs-ptfceh/​files/​resources/​lead_​action_​plan_​508.pdf.

24. U.S. EPA. Procedures for Chemical Risk Evaluation Under the Toxic Substances Control Act (TSCA). Federal Register . 89 FR 37028, May 3, 2024 (FRL-8529-02-OCSPP). https://www.govinfo.gov/​content/​pkg/​FR-2024-05-03/​pdf/​2024-09417.pdf.

25. U.S. EPA. TSCA Work Plan for Chemical Assessments: 2014 Update. October 2014. https://www.epa.gov/​sites/​default/​files/​2015-01/​documents/​tsca_​work_​plan_​chemicals_​2014_​update-final.pdf.

26. U.S. EPA. 2012 TSCA Work Plan Chemicals. June 2012. https://www.epa.gov/​sites/​default/​files/​2014-02/​documents/​work_​plan_​chemicals_​web_​final.pdf.

Authority: 15 U.S.C. 2601 et seq.

Dated: December 16, 2024.

Michal Freedhoff,

Assistant Administrator, Office of Chemical Safety and Pollution Prevention.