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Dietary SupplementsJoint Committee

Meeting

May 20, 2007

Recommended Changes to Pass/Fail Criteria for Metal Contaminants

Clif McLellanDirector of Toxicology Services

NSF International

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Presentation Outline

• Review ballot submitted to change pass/fail criteria for cadmium, chromium and lead Background of current criteria and reason for change

– How were proposed criteria derived?– How are values calculated?– Current vs proposed levels– Impact of change for certified products

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Background of current criteria and reason for change

• The current pass/fail criteria were originally established in 2003. The criteria were chosen because;– it was felt that using international criteria would better reflect the

international focus of this program. – No data were available indicating the level of metal

contaminants that would be expected.

• Since 2003, the program has developed more as a North American Standard and it is now believed that the basis of the pass/fail criteria should be more reflective of North American Standards and be based on health effects endpoints whenever possible.

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How were proposed criteria derived (cadmium, chromium and lead)?

• A review was performed to determine the best human health risk assessment available for cadmium, chromium and lead.

• For cadmium and chromium the U.S. EPA risk assessments were determined to be the most current and used state-of-the art risk assessment procedures.

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How were proposed criteria set (Lead)?

• Since there is no current safe level set for lead an alternate approach was required which met the following criteria;– as low as was achievable based on current

test results– be more protective of sensitive sub

populations (children and pregnant women).

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How are the criteria calculated based on daily safe levels?

Finished Product

Criteria

Rfd (mg metal /kg-bw-day) * 60 kg-bw * RSC

--- mg metal / day

RSC = Relative Source Contribution = 0.1 (10% of daily acceptable level).

Lab evaluation

Lab result (mg metal / g product) * maximum recommended daily dose (g product / day)

---- mg metal /day

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How are the criteria calculated based on daily safe levels?

Raw Ingredient

Criteria

Rfd (mg metal /kg-bw-day) * 60 kg-bw * RSC * 1/AUL * Unit conversion

--- ug metal / g ingredient --- ppm

RSC = Relative Source Contribution = 0.1 (10% of daily acceptable level)

AUL = Assumed Use Level = 1000 mg ingredient

Unit Conversion = 106 ug metal / 1g metal

* Raw ingredients can be evaluated based upon a use level recommended by manufacturer

Lab evaluation

Lab result (ug metal / g ingredient) ---- ppm

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What other levels have been established (units - ug/day)?Cadmium Chromium VI Lead

CA-Prop 65 Repro 4.1 - 0.5

CA-Prop 65 Cancer - - 15

Canada NHPD 5.4 17.4 17.4

NSF Current 6 20 20

NSF Proposed 4.1 Commerce

(6)

20 0.5 and 15

US ATSDR 12 - - no threshold

US FDA- Shellfish 55 - 6, 25 and 75

EU-Foodstuff 60 - 214

WHO/JECFA 60 - 214 Adult

35 Child (10kg)

EPA - IRIS 60 40

based on Cr VI

- no threshold

FDA- Bottled Water

–Based on 2L

5 200 based on total chrome

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EPA Water

– Based on 2L

5 200 based on total chrome

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Raw Materials - Current vs Proposed Levels

5.3.1.1 Raw materials – Current

Raw materials shall not contain undeclared metals in amounts greater than the following:

– cadmium content shall not exceed 0.3 ppm;– chromium (VI) content shall not exceed 2 ppm;– lead content shall not exceed 10 ppm; and

5.3.1.1 Raw materials – Proposed

Raw materials shall not contain undeclared inorganic metals in amounts greater than the following:

– cadmium content shall not exceed 4.1 ppm;– chromium (VI) content shall not exceed 20 ppm;– lead content shall not exceed 15 ppm; and

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Finished Products - Current vs Proposed Levels

5.3.1.2 Finished products – Current Finished products shall not contain undeclared metals at rates of intake greater than the following:

– cadmium content shall not exceed 0.006 mg/d;– chromium (VI) content shall not exceed 0.02 mg/d;– lead content shall not exceed 0.02 mg/d;

5.3.1.2 Finished products - ProposedFinished products shall not contain undeclared inorganic metals at rates of intake greater than the

following:

– cadmium content shall not exceed 0.0041 mg/d;– chromium (VI) content shall not exceed 0.02 mg/d;– lead content in products marketed for children or women shall not exceed 0.0005 mg/d; – lead content in all other products shall not exceed 0.015 mg/d; and

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Requested Action?

Ballot proposed levels for adoption to Dietary Supplement Standard for inorganic

cadmium, chromium VI and lead

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Basis for Current Criteria

ContaminantFinished Product Basis -

Level (mg/day)Raw Ingredient Basis -

Level (ppm)

Cadmium

Joint FAO/WHO Expert Committee on Food Additives Provisional Tolerated Weekly Intake for cadmium - 0.006 mg/day.

WHO Monographs on Selected medicinal plants - 0.3 ppm.

Chromium VI EPA Reference Dose - 0.02 mg/day. EPA Reference Dose - 2 ppm chromium w as derived.

Lead

Joint FAO/WHO Expert Committee on Food Additives Provisional Tolerated Weekly Intake for Lead - 0.02 mg/day.

WHO Monographs on Selected Medicinal Plants - 10 ppm.

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Relative Source Contribution

• Definition: A factor that is used to proportion the total acceptable level of a contaminant for a single source of exposure.

• If a proportion of the acceptable level for a contaminant is not considered, the compounding of exposure from various sources would result in an unacceptable daily exposure.

• Sources of exposure to consider: oral, dermal or inhalation.– For oral exposure consideration would be for water, food (various types)

and supplements.

• Example default source contributions are food (80%) and water (20%) when air sources are known to be minimal or insignificant.

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Source Contribution - How could you determine a source contribution for dietary supplements for a contaminant as a

proportion of total daily exposure?

• Weight? – Example: 2 g DS / 3 kg food +2 kg water = 0.04 %

• Volume? – Same result.

• Base it on exposure levels, when known?– Subtract each known source of exposure from the “safe” level.

» Safe level – oral – dermal – inhalation

Limitations: would you use averages? 90, 95, 99 percentile? Which population(s)? Are data available? The “safe” level for heavy metals is either “0” or very low.

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Source Contribution – Why did we use 10% ?

• Most risk values are good to one significant figure (chromium, cadmium and mercury) and 10% of the daily total would result in a numerically insignificant exposure.

• Other established source contributions are 80% food and 20% water, and we felt that dietary supplements should contribute less than the amount allowed for food and water while at the same time not be too restrictive.

• Contaminant levels should be set so they provide protection based on human

health endpoints.