Huff et al. 2025 — Heavy metals in spices from Lancaster, PA
This study measured arsenic, cadmium, and lead in 116 spice samples (82 store-purchased, 34 home-donated) from Lancaster, Pennsylvania, a city with a notably high refugee resettlement rate and elevated childhood blood lead levels relative to the state average. As, Cd, and Pb were detected in 90%, 93%, and 98% of samples respectively, using FDA EAM 4.7 ICP-MS method at an ISO 17025-accredited laboratory. Lead was the dominant concern: 40.5% of all samples exceeded New York State Department of Health (NYSDOH) 2023 guidance of 0.21 ppm, with a single curry powder sample reaching 31.9 ppm, the only sample exceeding the FDA reference level for Pb. The study adds to a growing body of US evidence that spices are an underrecognized lead exposure pathway, particularly for immigrant and refugee communities with high spice consumption, and reinforces the need for a national regulatory limit for lead in spices.
Key numbers
Overall median concentrations (n = 116):
- tAs: 0.048 ppm (IQR: 0.028–0.075), range 0.007–0.497 ppm
- Cd: 0.056 ppm (IQR: 0.034–0.083), range 0.007–0.333 ppm
- Pb: 0.177 ppm (IQR: 0.086–0.339), range 0.007–31.9 ppm
Store-purchased (n = 82) vs. home-donated (n = 34) medians:
- tAs: 0.055 vs. 0.034 ppm (significant difference, p = 0.001)
- Cd: 0.055 vs. 0.058 ppm (not significant, p = 0.98)
- Pb: 0.182 vs. 0.119 ppm (not significant, p = 0.06)
Proportion exceeding NYSDOH 2023 limits:
- tAs (limit 0.21 ppm): 6.03% all; 8.54% store-purchased; 0.00% home-donated
- Cd (limit 0.26 ppm): 3.45% all; 2.44% store-purchased; 5.88% home-donated
- Pb (limit 0.21 ppm): 40.5% all; 43.9% store-purchased; 32.4% home-donated
Proportion exceeding WHO 2007 limits:
- tAs (5 ppm): 0.00%; Cd (0.3 ppm): 1.72%; Pb (10 ppm): 0.09%
Highest concentrations per analyte (all from same international store):
- tAs 0.497 ppm in turmeric from Thailand
- Cd 0.294 ppm in paprika from the USA
- Pb 31.9 ppm in curry powder from the USA
Estimated daily intake (EDI) for children age 1–5 (IR = 0.35 g/day, BW = 15 kg):
- Median: As 0.016 µg/day, Cd 0.020 µg/day, Pb 0.062 µg/day
- Highest: As 0.174 µg/day, Cd 0.117 µg/day, Pb 11.2 µg/day (curry powder)
LOD for all three metals: 0.01 ppm; non-detects replaced with LOD/√2.
Spice types in store-purchased samples: masala (28%), curry powder (17%), paprika (7%), turmeric (6%), annatto (5%), other (37%). Origins primarily India (28%) and USA (23%).
Methods (brief)
ICP-MS (Agilent 7900) using FDA EAM 4.7 method; samples digested on hot block with HNO3, H2O2, and HCl. Analysis by AGQ Labs, ISO 17025:2017 accredited. LOD 0.01 ppm for As, Cd, and Pb. Note: As reported as total arsenic (not speciated); NYSDOH As limit is specific to inorganic As, so authors note the total As approach is conservative and actual iAs exceedance rates may be lower. Spice intake for children (EPA WWEIA FCID database, age 1–5): 0.35 g/day. Statistical comparisons by Wilcoxon rank sum test; Spearman correlation used for metal-metal relationships (As-Pb: rs = 0.58, p < 0.001; As-Cd: rs = 0.33, p = 0.0003; Cd-Pb: rs = 0.34, p = 0.002).
Implications
Certification: The 40.5% exceedance rate for NYSDOH lead guidance in commercial spice samples from a single US city is among the highest published for any US market basket study. The 31.9 ppm Pb in a curry powder sample from a US-origin product is particularly notable as it far exceeds the 0.21 ppm NYSDOH threshold and the 10 ppm FDA color additive limit, and represents a genuine acute exposure risk. The As-Pb correlation (rs = 0.58) is consistent with the lead chromate adulteration pathway identified in related literature. HMT&C supplier audits for spice blends and curry powders should include lead testing as a primary control.
Courses: Documents the immigration and refugee health angle: Lancaster has disproportionately high refugee resettlement and elevated childhood BLLs, and spices are both culturally important and a documented lead source in this community. Illustrates how standard childhood lead risk assessments (focused on paint and water) miss spice exposure, especially in immigrant households. Strong case study for QA training on underregulated food categories.
App: Provides US commercial market data for mixed spice products (masala, curry powder) showing median Pb of 0.177 ppm and maximum Pb of 31.9 ppm; useful for flagging spice blends and curry powders as higher-risk subcategories relative to single-ingredient spices. Total As in turmeric reaching 0.497 ppm supports flagging turmeric as a tAs-elevated spice ingredient.