Health Risk Assessment: Lead in Children's Toys

Overview

This Institute of Environmental Science and Research (ESR) Client Report FW21014, prepared by Jeff Fowles for the New Zealand Ministry of Health in May 2021 and peer-reviewed by Peter Cressey, is a generic toxicological risk assessment of children’s exposure to lead (Pb) from toys containing Pb at or above the New Zealand allowable migration limit of 90 mg Pb/kg. The report contextualises Pb-from-toys against background environmental Pb exposures (diet, drinking-water, soils/dust, air), reviews international regulatory limits for Pb in children’s products, and computes three explicit exposure scenarios for a 2-3 year old child. The principal finding is that a toy at the 90 mg Pb/kg allowable limit, under a swallowing scenario, can deliver a Pb dose of 27 µg/day — by itself roughly equal to the daily Pb dose that would result in a 5 µg/dL (0.24 µmol/L) blood Pb level in young children, the recently lowered NZ and US notification level — so non-compliant toys remain a significant individual-child hazard even though Pb in toys is not a population-wide concern.

Key numbers

Blood Pb reference values and notification levels

• NZ Ministry of Health blood Pb notification level (2021): 0.24 µmol/L (5 µg/dL), lowered from the prior 0.48 µmol/L (10 µg/dL) (Ministry of Health 2021; p. 1, 3, 4, Table 1).
• US CDC blood Pb reference level (2012): 5 µg/dL, set at the 97.5th percentile of the blood Pb distribution in US children aged 1-5 years in the NHANES database (CDC 2012; p. 2).
• US CDC potential future reference level: 3.5 µg/dL “under consideration” at the time of the report (Zartarian et al. 2017; p. 3).
• Blood Pb notification levels — international (Table 1, p. 4):
• New Zealand, Australia, USA: 0.24 µmol/L (5 µg/dL)
• UK, Canada: 0.48 µmol/L (10 µg/dL)
• NZ biomonitoring blood Pb (2014-2016, ‘t Mannetje et al. 2020): geometric mean 0.86 µg/dL in 191 NZ children aged 5-18 years (p. 2).
• US NHANES blood Pb (2015-2016): geometric mean 0.758 µg/dL (ages 1-5), 0.57 µg/dL (ages 6-11) (p. 2, Figure 1).
• NZ population blood Pb trend: ~90% reduction since the 1970s, attributed primarily to removal of Pb from petrol and soldered tin cans (‘t Mannetje et al. 2020; p. 2).

Blood Pb–IQ dose-response

• Lanphear et al. 2005 pooled dose-response: 1-2 µg/dL increase in blood Pb corresponds to a deficit of 1 IQ point (CalEPA 2009; SNC-Lavalin 2012; p. 3, Figure 2).
• JECFA 2011 dietary-dose to IQ deficit: daily Pb dose of 0.3 µg Pb/kg BW/day equates to a 0.5 IQ point deficit (JECFA 2011; p. 3).
• JECFA dietary-Pb to blood-Pb mapping: 1 µg Pb/day dietary intake equates to a blood Pb of 0.023-0.07 µg/dL; by inverse, 10 µg/dL blood Pb equates to a Pb exposure of 140-430 µg/day (JECFA 2011; p. 6).
• Threshold: no known threshold for adverse blood-Pb effects; ALARA principle governs Pb risk management (p. 4).

Daily Pb intake reference values (Table 2, p. 8)

Background environmental Pb exposures (NZ and analogues)

• Diet (US, Spungen 2019): mean dietary Pb exposure 1-3.4 µg/day in children aged 1-6 years (0.06-0.23 µg/kg bw/day or 0.42-1.6 µg/kg bw/week); major contributions from grains, fruit, dairy, and mixtures (hamburgers, pizza, lasagna, soups) (p. 8).
• Diet (NZ, Pearson et al. 2018): dietary Pb 0.53-2.2 µg/kg bw/week for toddlers (1-3 years) and children (5-6 years) (p. 8).
• Drinking-water (NZ MAV): 0.01 mg/L (10 µg/L); at estimated mean daily water consumption for a 5-6 year old NZ child, ≈0.004 mg/day (4 µg/day) (Cressey and Horn 2016; p. 8).
• House-dust Pb (Christchurch, Kim and Fergusson 1993): geometric mean 573 mg/kg across 120 homes (p. 9).
• House-dust Pb (Sydney, Doyi et al. 2019): mean 299 mg/kg, 95th percentile 364 mg/kg across 224 homes; 19.2% of children in these homes had predicted blood Pb exceeding 5 µg/dL; using the default Australian dust intake parameter of 50 mg/day, mean daily Pb intake from house dust ≈15 µg/day (p. 9).
• Sydney 1-2 year olds (Gulson et al. 2018): geometric mean contributions of daily Pb to 108 toddlers across air, diet, water, and dust/soil were 0.09%, 42%, 5.3%, and 42% respectively (Figure 4, p. 7, 10).
• Air: following the elimination of Pb in petrol, exposure to Pb from outdoor ambient air is now only a very small fraction of daily Pb exposure (ATSDR 2021; Gulson et al. 2018; p. 9).

Pb in toys — supporting literature

• NZ 2010 Herald report: painted bargain-store toys with Pb migration “exceeding” the 90 mg/kg limit; “some concentrations over 28,000 mg Pb/kg” (NZ Herald 2010; p. 5).
• NZ Trade Aid 2017 recall: 150 painted nesting dolls (sourced from India) recalled following detection of “undisclosed levels of Pb”; other products from the same shipment were free of detectable Pb (Winter 2017; p. 5).
• CPSC 1997 PVC toy wipe study: a Barbie™ toy phone cord accessory yielded 0.7 µg Pb per wipe; the report estimated 43 wipes/day would be required to reach a 15 µg Pb/day dose using a 50% hand-to-mouth transfer efficiency (CPSC 1997; p. 5).
• CPSC 1997 ASTM/EN 71-3 reference: the 1997 report cites 90 µg Pb/g (90 ppm) surface coating limit, based on the 15 µg Pb/day dose corresponding to a steady-state blood Pb of 10 µg/dL (p. 5).
• CPSIA derivation: 90 ppm allowable Pb limit in coatings “appears to be based on preventing a daily intake of 15 µg” (Schmidt 2008; p. 6).
• CPSC enforcement record: 1977-2014, 350 recalls of >200 million consumer items for violations of the Pb paint standard or other Pb exposure risks (Dignam et al. 2019; p. 6).
• EU RAPEX: numerous Pb-non-compliance notifications for toys, with the majority originating from items manufactured or imported from China; some with Pb migration levels up to 1,442 mg Pb/kg (European Commission 2021; p. 9).
• Igweze et al. 2020 (Nigeria): Pb detected in all 30 China-manufactured toys surveyed, all between 5-10% of the 90 ppm regulatory limit; estimated daily Pb exposure ≈1-2 µg/day for a 15 kg child through mouthing and swallowing Pb residues (p. 9).
• Kang and Zhu 2015 (Beijing, 72 low-cost plastic toys): 27 toys (37.5%) contained Pb above 100 ppm; bioaccessible amount of Pb using dilute HCl was only 0.8-8.8%, thus satisfying the Chinese standard of <90 ppm bioaccessible Pb (p. 13).
• Cui et al. 2015: Pb transfer from toys into saliva at low rate (<1%); much higher transfer (not numerically specified in extract) observed with acidic fluid (p. 13).
• Sahmel et al. 2015 (hand-to-mouth Pb transfer): “typical” hand-to-mouth (saliva) transfer efficiency 24%; conservative default 50% (used by CalEPA 2011) (p. 13).

Regulatory limits for Pb in children’s toys

• New Zealand: Unsafe Goods (Lead in Children’s Toys) Indefinite Prohibition Notice (2009, in force at the time of the report); migration limit 90 mg Pb/kg (Commerce Commission 2021; p. 11).
• Australia: 90 mg Pb/kg migration limit (Product Safety Australia 2021; p. 11).
• USA: under CPSIA (Public Law 110-314, in force 2008), total Pb content of children’s products ≤100 ppm (mg Pb/kg material), and ≤90 ppm specifically for coatings (CPSC 2021; p. 6, 11). Restated as ≤100 ppm total Pb content in accessible parts and ≤0.009% (90 ppm) Pb in paint or surface coatings (p. 11). Toy safety testing required to meet ASTM F963 since 2017, using the same 15 µg Pb/day criterion (CPSC 2017; p. 6).
• Health Canada: 90 mg Pb/kg migration limit for accessible parts of toys, particularly for coatings (Health Canada 2020; p. 11).
• EU Directive 2009/48/EC (Toy Safety Directive, 2009): migration limits 13.5 mg Pb/kg (dry/brittle/pliable toy materials), 3.4 mg Pb/kg (liquid or sticky toy materials), 160 mg Pb/kg (scraped-off material) (European Commission 2009; p. 11).
• EU 2018 amendment: migration limits lowered to 2.0, 0.5, and 23 mg Pb/kg respectively for the three toy material categories (SGS 2017; p. 12).
• EU EN 71-3 / accessible-parts criterion (ECHA 2013): the migration limit does not apply when the rate of Pb release from an article (whether coated or not) does not exceed 0.05 µg/cm² per hour (0.05 µg/g per hour) (p. 11-12).

Exposure-scenario assumptions (Section 5, p. 13-14)

• Pb concentration in toy: 90 mg Pb/kg (the NZ allowable limit).
• Toy mass per contact event: 0.01 kg (10 g) assumed for the surface-contact scenarios; 0.001 kg (1 g) for the swallowing scenario.
• % bioaccessible fraction (BA): 0.01 (1%) for the saliva-transfer scenarios, from Cui et al. 2015.
• Transfer efficiency (TE) per contact event: 24%, from Sahmel et al. 2015 (“a range of 1% to 24% was used to estimate Pb transfer to saliva or hands from toys”; the upper bound is used in the scenarios).
• Hand-to-mouth events/day: 20 (Cressey and Horn 2016).
• Object-to-mouth events/day: 10 (Cressey and Horn 2016).
• Oral absorption fraction (Abs): 0.30 (30%), the US EPA IEUBK model default for ingested soil Pb (USEPA 2021).
• Oral bioavailability (swallowed Pb): 2-80% reported range (Zia et al. 2011); 30% used for Scenario 3 consistent with the IEUBK default.
• Dermal absorption of Pb from toys: assumed negligible relative to oral intakes.

Three exposure scenarios — calculated daily Pb dose (2-3 year old child)

• Scenario 1 — touching/mouthing a 10 cm² surface of a 10 g toy at the 90 mg/kg NZ allowable limit (Section 5, p. 14):
• Object-to-mouth: 90 µg Pb/g × 10 g toy × 0.01 BA × 0.24 TE × 10 events/day × 0.30 Abs = 6.5 µg Pb/day.
• Hand-to-mouth: 90 µg Pb/g × 10 g toy × 0.01 BA × 0.24 TE × 20 events/day × 0.30 Abs = 13 µg Pb/day.
• Scenario 2 — mouthing/handling a non-compliant toy yielding 0.7 µg Pb/contact (CPSC 1997 dislodgeable Pb measurement; Section 5, p. 14):
• Object-to-mouth: 0.7 µg Pb × 10 events/day × 0.30 Abs = 2 µg Pb/day.
• Hand-to-mouth: 0.7 µg Pb × 20 events/day × 0.30 Abs = 4 µg Pb/day.
• Total Scenario 2: 6 µg Pb/day.
• Scenario 3 — swallowing 1 g of a non-compliant toy at the 90 mg/kg NZ allowable limit (Section 5, p. 14):
• Total Pb in 1 g toy = 90 mg Pb/kg × 0.001 kg = 0.09 mg = 90 µg Pb.
• Exposure: 90 µg Pb/day × 0.30 oral bioavailability = 27 µg Pb/day.
• The report explicitly notes that the scenarios estimate “rare events and short-term timeframes,” not typical or long-term exposures (p. 14).

Estimated daily Pb exposures in context (Table 3, p. 15)

Risk characterisation conclusions

• The 27 µg Pb/day estimate from Scenario 3 (swallowing a 1 g toy at 90 mg Pb/kg), by itself, “would be expected to roughly equal the daily Pb dose resulting in a 5 µg Pb/dL (0.24 µmol/L) blood level in a young child” (p. 15, Figure 5).
• “While the actual use of a given toy may only last weeks or months, the impact on neurodevelopment over a subchronic period is unknown, and daily exposures during this time could therefore pose a risk of serious harm to a developing child” (p. 15).
• The report concludes that Pb in toys is not a population-wide health concern but can represent significant hazard to individual children who may come into contact with non-compliant toys (Executive Summary, p. 1; Conclusions, p. 17).

Methods (brief)

This is a generic toxicological risk-assessment report; no primary analytical work was carried out, and no LOD/LOQ is applicable. The report’s method is the standard health-risk-assessment workflow as applied by ESR for NZ regulatory clients: (i) compile authoritative blood-Pb–effect dose-response and tolerable-intake reference values from JECFA (2011), EFSA (2010), CalEPA (2009), SNC-Lavalin (2012), Health Canada (2013), US FDA (2020), and US EPA (2018, 2021); (ii) compile NZ and international background exposure data — dietary (NZ TDS 2018; Spungen 2019), drinking-water (NZ MAV; Cressey and Horn 2016), house-dust (Kim and Fergusson 1993 for Christchurch; Doyi et al. 2019 for Sydney; Gulson et al. 2018 for Sydney IEUBK modelling), air (ATSDR 2021) — and biomonitoring blood-Pb data (NHANES; ‘t Mannetje et al. 2020 for NZ); (iii) compile international regulatory limits for Pb in children’s toys (NZ, US CPSIA, EU 2009/48/EC and its 2018 amendment, Health Canada, Australia); (iv) compute three explicit exposure scenarios for a 2-3 year old child using transfer-efficiency parameters from Sahmel et al. (2015) and CalEPA (2011), saliva-bioaccessibility from Cui et al. (2015), hand-to-mouth/object-to-mouth event frequencies from Cressey and Horn (2016), and oral-absorption defaults from the US EPA IEUBK model (USEPA 2021); (v) characterise risk by mapping the per-scenario Pb dose back to expected blood-Pb concentrations through the Zartarian et al. (2017) modelled relationship. The report is structured into Executive Summary, Introduction (1.1 Pb exposures and children’s health, 1.2 Blood Pb notification levels), Concerns about Pb exposures from children’s products (NZ, international), Environmental sources of Pb exposure in children (diet, drinking-water, soils/dust, air, toys), Allowable levels of Pb in children’s products, Exposure Scenarios, Risk Characterisation, Discussion, Conclusions, and References. Authorship: Jeff Fowles (Tox-Logic). Peer review: Peter Cressey (ESR). Manager sign-off: Rob Lake (ESR Risk Assessment & Social Systems Group). Client: NZ Ministry of Health. Report number: FW21014.

Implications

• Regulatory baseline (Pb in toys, NZ). This Client Report is the ESR/NZ Ministry of Health risk-assessment basis for evaluating the existing 90 mg Pb/kg migration limit for children’s toys in force in New Zealand under the Unsafe Goods (Lead in Children’s Toys) Indefinite Prohibition Notice 2009. The report’s principal conclusion — that the 90 mg Pb/kg limit, while consistent with similar limits in the US, Canada, and Australia and broadly consistent with the EU’s tighter 2018 migration values, is capable of delivering a per-child daily Pb dose sufficient to elevate blood Pb to the new 5 µg/dL notification level under a single-toy swallowing scenario — is the report’s flagged basis for considering whether “a more conservative allowable limit appears to be justified, so long as this is reasonably achievable” (Discussion, p. 16).

• Regulatory baseline (Pb in toys, EU). The report is one of the documents that observes the EU’s 2018 amendment to Directive 2009/48/EC reducing Pb migration limits to 2.0, 0.5, and 23 mg Pb/kg across the three toy material categories — substantially tighter than NZ, US CPSIA, Health Canada, and Australia — and notes that “the technical calculations justifying the amended values, which deviate from the other authoritative regulations, could not be located at the time of this report” (p. 12).

• HMTc audit implications. For HMTc certification work on children’s-product categories that include toys (and on mouthed sub-categories such as pacifiers and teething aids), this report is the NZ-agency-commissioned anchor demonstrating two things relevant to threshold-setting governance: (i) the agency-level position that the existing 90 mg Pb/kg migration limit, although internationally consistent, can result in per-day Pb intakes sufficient to elevate blood Pb to the lowered 5 µg/dL notification level under conservative scenarios, justifying ALARA-driven reductions where reasonably achievable (consistent with the wiki’s Part 2 ratcheting frame); (ii) explicit numerical exposure scenarios that translate the 90 mg Pb/kg migration limit into per-day Pb dose estimates (6.5-13 µg/day for surface contact at the limit; 27 µg/day for the swallowing scenario at the limit). HMTc threshold-setting for pacifiers-and-sucking-teething-aids, toys-painted, and toys-substrate-materials categories can cite this report as the regulatory-alignment anchor for either of these positions.

• App. Not directly relevant to ingredient contamination_profile data because no food-matrix occurrence values are reported. Relevant to a future toys/children’s-product screening surface that explains the regulatory logic behind Pb migration-limit values and translates them into per-day Pb dose for consumer and brand-QA users.

• Courses. Worked example for the regulatory-history module of (i) how a national regulatory agency commissions a risk assessment to evaluate whether an existing migration limit remains defensible in light of a lowered downstream blood-Pb notification level (here, NZ’s 2021 move from 10 to 5 µg/dL); (ii) how the ALARA principle is operationalised in the absence of a defensible safe-effect threshold; (iii) how transfer-efficiency, bioaccessibility, mouthing-event frequency, and oral-absorption parameters compound multiplicatively into a per-day Pb dose estimate (Section 5 exposure-scenario derivations are immediately reusable as a teaching unit). Also a primary-source illustration of the regulatory tension between feasibility-driven migration limits and the agency’s preferred ALARA position — directly relevant to the wiki’s Part 19 rationale-tag vocabulary (feasibility-driven vs regulatory-alignment vs precautionary).

Related evidence

• Lead
• General toys with paint/surface coatings
• Toy substrate materials (accessible plastics/metals/woods/rubbers)
• Pacifiers and sucking/teething aids

Update history

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