Heavy Metals

Heavy metals are naturally occurring elements with high atomic weights and densities at least 5 times greater than water.  As a result of their multiple applications (industrial, domestic, agricultural, medical and technological) they have been widely distributed into the environment.  This allows them to become incorporated into plant tissues which are then used as raw materials in foods and other products.  Because of their high degree of toxicity, Arsenic (As), Cadmium (Cd), Lead (Pb), and Mercury (Hg), are four metals that are of great public health significance and are routinely determined in raw ingredients and finished food products as they can greatly affect human and animal health.  These elements are considered systemic toxicants that are known to induce multiple organ damage and birth defects even at low levels of exposure.  The acceptable limits of concentration and/or daily ingestion of these metals vary from product to product and by region (country, state, etc.) and are not always clearly defined.

Nutritional Minerals

As one of the groups of essential micronutrients, minerals play an important role in human and animal health.  From maintaining bone density to aiding in the transport of oxygen throughout the body to regulating nerve function, a mineral-rich diet can greatly improve well being.  Unfortunately, many people do not get enough of certain minerals (most commonly calcium, iron, and potassium) and get too much of others (sodium). For this reason, many food producers will fortify their products directly with mineral salts.  However, some of the essential trace elements (notably chromium, molybdenum, and selenium) can be harmful if consumed in too great of concentrations.  For these reasons, as well to satisfy the NLEA labeling requirements, routine mineral testing can be used to back up health claims as well as ensure accurate fortification in product formulations.

A minimum of 0.5 grams of solid or non-aqueous samples is required for digestion/analysis. 

10 ml is the minimum required for an aqueous sample.

ElementAbbreviationDrinking Water mg/L (PPM)SpicesUSP 232/233Food (USA)TeaCannabis
mg/Kg (PPM)
CA Prop 65Codex
LeadPb0.015     1.0 0.1-1.5 mg/kg, 0.010 mg/L
CadmiumCd0.005     0.4 0.05- 2.0 mg/kg, 0.003 mg/L
MercuryHg0.002     0.2 0.1-1.0mg/kg, 0.001 mg/L
ArsenicAs0.010     0.4 0.1 mg/kg, 0.01 mg/L
ThalliumTl0.002     NA  
SeleniumSe0.05     NA  
BerylliumBe0.004     NA  
ChromiumCr0.1     NA  
CopperCu1.3     NA  
AnalyteAbbreviationLOQ (PPB)Range (ppm)
ArsenicAs200.020 – 50,000
BariumBa200.020 – 50,000
CadmiumCd100.010 – 50,000
ChromiumCr200.020 – 50,000
CobaltCo200.020 – 50,000
CopperCu200.020 – 50,000
GalliumGa200.020 – 50,000
IronFe2500.25 – 500,000
LeadPb50.005 – 50,000
ManganeseMn200.020 – 50,000
MercuryHg50.005 – 50,000
MolybdenumMo200.020 – 50,000
NickleNi200.020 – 50,000
SeleniumSe1000.10 – 50,000
StrontiumSr200.020 – 50,000
ThalliumTl200.020 – 50,000
TinSn100.010 – 50,000
TungstenW50.005 – 50,000
VanadiumV200.020 – 50,000
ZincZn2500.25 – 500,000
AnalyteAbbreviationLOQ (PPM)Range (PPM)
CalciumCa80.0080 – 500,000
ChromiumCr0.030.03 – 50,000
CopperCu0.030.03 – 50,000
IronFe0.800.08 – 50,000
MagnesiumMg2.002.0 – 50,000
ManganeseMn0.030.03 – 50,000
MolybdenumMo0.030.03 – 50,000
PhosphorousP80.0080 – 500,000
PotassiumK80.0080 – 50,000
SeleniumSe0.100.10 – 50,000
SodiumNa4.004.0 – 50,000
ZincZn0.800.080 – 50,000