California Prop 65 Testing
Compliance Analysis

Protect your brand from lawsuits with our accredited California Prop 65 testing services. We provide ultra-low level detection of Lead, Cadmium, Arsenic, and Mercury to ensure compliance with California's Safe Harbor limits.

Accreditation
ISO/IEC 17025:2017 · Cert L24-482-R2
Method
AOAC 2015.01 · ICP-MS
Target Analytes
Lead, Cadmium, Arsenic, Mercury

Navigate Regulations with Prop 65 Compliance Screening

California Proposition 65 (The Safe Drinking Water and Toxic Enforcement Act) is one of the strictest chemical regulations in the world. It requires businesses to provide a Clear and Reasonable Warning if their product exposes consumers to chemicals known to cause cancer or reproductive toxicity.

For food manufacturers, the primary risk involves naturally occurring heavy metals — a subset of our broader chemical contaminant testing. A simple "Pass" from an FDA perspective may still fail Safe Harbor limits, leading to expensive lawsuits. Ensure your nutrition facts labels are compliant alongside any Prop 65 warnings. AGT Food Labs delivers the precise, low-level California Prop 65 testing needed to determine whether your product requires a warning label before it ships into the California market.

The California Prop 65 Testing Process

From sample submission to exposure calculation, we guide you through compliance.

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01. Request
Request a Prop 65 screen and provide your product's Daily Serving Size (crucial for the exposure calculation).
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02. Shipping
Send 100g of sample to our lab. For robust California Prop 65 testing, we recommend submitting 3 distinct production lots to account for variability.
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03. ICP-MS Analysis
We use Inductively Coupled Plasma Mass Spectrometry (ICP-MS) per AOAC 2015.01 (SOP 046) to detect metals at parts-per-billion levels.
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04. Exposure Report
We convert the results into micrograms/day exposure and compare against the Prop 65 Safe Harbor thresholds — MADL (Maximum Allowable Dose Level for reproductive toxicity) and NSRL (No Significant Risk Level for cancer).

California Prop 65 Testing Services

Specialized screening designed to detect "The Big 4" heavy metals at trace levels.

ICP-MS instrument used for California Prop 65 testing of heavy metals
The Big 4

Heavy Metals Screen for Prop 65

We test for the four heavy metals most commonly cited in Prop 65 lawsuits using ICP-MS per AOAC 2015.01 (SOP 046) under our PJLA ISO/IEC 17025 scope. Standard labs often rely on ICP-OES, which has detection limits in the ppm range — too high for Prop 65. Our ICP-MS reaches parts-per-billion (ppb) sensitivity, which is essential for accurate California Prop 65 testing and for preventing False Pass results that lead to litigation.

Wider element panel: When buyers need more than the Big 4, we extend coverage to a 14-element ICP-MS panel (Zn, Cu, Se, Cr, Mn, Sn, Na, K, Ca, Mg, Fe, Al, Ni) per AOAC 985.01 / 993.14 (SOP 047).

Target Analytes (Big 4):
  • Lead (Pb): The #1 cause of Prop 65 notices.
  • Cadmium (Cd): Common in cocoa, seeds, and shellfish.
  • Arsenic (As): Total arsenic by ICP-MS — conservative screen for the inorganic NSRL; speciation available externally for rice and seaweed matrices.
  • Mercury (Hg): Concern for seafood products.
Daily exposure calculation example for California Prop 65 compliance (Concentration x Serving Size = micrograms per day)
Risk Assessment

Exposure Calculation for Prop 65

Prop 65 limits are based on Total Daily Exposure (µg/day), not just concentration (ppm). A simple concentration number doesn't tell the full story. We perform the critical math for you:

The Exposure Formula:
Concentration (ppm) × Daily serving size (g) = Exposure (µg/day)

Example: A protein powder has 0.1 ppm Lead.
• If serving is 5g: 0.1 × 5 = 0.5 µg/day (PASS)
• If serving is 50g: 0.1 × 50 = 5.0 µg/day (FAIL — Warning Required)

We help you define the correct serving size and compare your results directly against the MADL (Maximum Allowable Dose Level). Accurate California Prop 65 testing combines low-level ICP-MS data with this exposure math — failure to meet Safe Harbor limits can result in costly litigation.

Technical Capabilities

Using advanced ICP-MS technology to reach parts-per-billion (ppb) detection under our ISO/IEC 17025 scope.

Analyte Method Reference Technique Typical Limit of Quantitation (LOQ)
Lead (Pb)AOAC 2015.01, SOP 046ICP-MS5 ppb (0.005 ppm)
Cadmium (Cd)AOAC 2015.01, SOP 046ICP-MS5 ppb (0.005 ppm)
Arsenic (Total)AOAC 2015.01, SOP 046ICP-MS10 ppb (0.010 ppm)
Mercury (Hg)AOAC 2015.01, SOP 046ICP-MS5 ppb (0.005 ppm)
14-Element Metals PanelAOAC 985.01 / 993.14, SOP 047ICP-MSvaries by analyte

Industries We Serve

California Prop 65 testing across the food & beverage categories most often cited in 60-Day Notices.

Chocolate and cocoa products tested for cadmium and lead under California Prop 65

Chocolate & Cocoa

Cadmium and lead screening for chocolate bars, cocoa powder, and confectionery — the highest-volume Prop 65 lawsuit category.

Protein powders and dietary supplements tested for heavy metals under Prop 65

Supplements & Protein Powders

Heavy-metal verification for plant-based protein, greens powders, and dietary supplements where concentrated plant matter aggregates soil metals.

Rice and cereal grain products tested for inorganic arsenic under California Prop 65

Rice & Cereal Grains

Total arsenic screening for rice, rice-based foods, and infant cereals — with external speciation referrals for inorganic As confirmation.

Seafood tested for mercury and cadmium under California Prop 65

Seafood & Sea Vegetables

Mercury and cadmium quantification for large fish, shellfish, kelp, and seaweed products with marine bioaccumulation risk.

Understanding Prop 65 Safe Harbor Limits

Prop 65 sets specific limits for Cancer (NSRL) and Reproductive Toxicity (MADL). Exceeding these requires a warning label.

Lead (Pb) Limit

0.5 µg/day (MADL)
This is the most strictly enforced limit. Consuming just one serving containing >0.5 micrograms of Lead may trigger a warning requirement.

Cadmium (Cd) Limit

4.1 µg/day (MADL)
Often an issue in chocolate, sunflower seeds, and spinach. Exceeding this daily intake level poses a reproductive toxicity risk.

Arsenic Limit

10 µg/day (NSRL)
The Prop 65 NSRL applies specifically to Inorganic Arsenic (the toxic form). Our scope reports Total Arsenic by AOAC 2015.01, which is the conservative screening proxy — for high-risk matrices like rice and seaweed, we recommend supplementing with external speciation analysis.

Common At-Risk Product Categories

Heavy-metal exposure varies sharply by ingredient. These categories most often trigger California Prop 65 testing reviews.

Product Category Primary Metal of Concern Typical Safe Harbor Risk
Chocolate & Cocoa ProductsCadmium, LeadHigh — bean origin and shell residue drive elevated levels
Protein Powders & Plant-Based SupplementsLead, Cadmium, ArsenicHigh — concentrated plant matter aggregates soil metals
Rice & Rice-Based FoodsInorganic ArsenicHigh — rice uptakes arsenic from paddy soils
Seaweed & Sea VegetablesInorganic Arsenic, CadmiumHigh — marine bioaccumulation
Seafood (large fish, shellfish)Mercury, CadmiumHigh — top of the food chain accumulation
Sunflower & Pumpkin Seeds, SpinachCadmiumModerate — naturally cadmium-accumulating crops
Spices, Herbs & BotanicalsLead, CadmiumModerate–High — soil contamination and processing exposure

Common Questions About California Prop 65 Testing

Expert answers for food manufacturers regarding Prop 65 compliance.

What is the legal limit for Lead under Prop 65?
The "Safe Harbor" limit (MADL) for Lead is 0.5 micrograms per day. This is calculated by multiplying the concentration in your food (ppm) by the serving size (grams). If the result is >0.5, a warning label is required unless you can prove the lead is "naturally occurring."
What is a "60-Day Notice"?
A 60-Day Notice is a legal document sent by a private enforcer (bounty hunter) alleging that your product contains chemicals above the safe harbor level without a warning. If you receive one, you have 60 days to respond before a lawsuit is filed. Proactive California Prop 65 testing helps prevent this by ensuring your labels are accurate before sale.
Are Organic products exempt from Prop 65?
No. "Organic" refers to how food is grown (no synthetic pesticides), but heavy metals are naturally in the soil. Organic products often have higher levels of heavy metals because they use natural fertilizers (like manure/compost) which can be rich in metals. Organic status offers no protection against Prop 65.
How often should I test my products?
Since heavy metals come from the soil, levels can vary by harvest. We recommend California Prop 65 testing on every new lot of raw ingredients initially. Once you establish a baseline, you can move to a quarterly surveillance schedule to maintain "Reasonable Care" defense.
How is Prop 65 different from FDA regulations?
The FDA sets limits based on "Acute Toxicity" (poisoning), while Prop 65 focuses on "Chronic Risk" (cancer/reproductive harm) over a lifetime. Prop 65 limits are often 100x to 1000x stricter than FDA limits, which is why dedicated California Prop 65 testing is needed even for FDA-compliant products. A product can be FDA compliant but still illegal to sell in California without a warning.
Does a positive test mean I cannot sell my product?
No. Prop 65 is a "Right to Know" law, not a ban. You can still sell your product if it exceeds the limit, but you MUST place a compliant Prop 65 Warning Label on the package. Failure to warn is what leads to lawsuits.

Don't Wait for a Notice of Violation.

Schedule accredited California Prop 65 testing today and sell with confidence in the California market.

Request a Prop 65 Screen
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