Table VI

Extracted Elemental Impurities Reported for Polyethylene (PE)

ElementConcentration (mg/kg unless noted)Extraction DetailsCommentsRef.
SolventConditions
AlNR1–0.10Low pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NRHigh pH (≈9)
NREthanol/water
0.0013% acetic acidSealed vessel, 40 °C for 10 days, 0.15 g sample/mL solventTotal pool = 7.2 mg/kg21
0.0043% acetic acidSealed vessel, 40 °C for 10 days, 0.15 g sample/mL solventTotal pool = 0.51 mg/kg21
1.5 mg/L0.2% Polysorbate 80Sealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventLow-density polyethylene resin423
0.50 mg/L0.1% EDTASealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
0.09pH 2.5
<0.01pH 9.5
BNR–8.9Low pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NR–0.92High pH (≈9)
NR–5.9Ethanol/water
BaNRLow pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NRHigh pH (≈9)
NREthanol/waterSealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
<0.01pH 2.5
0.01pH 9.5
0.4pH 2.5, pH 9.5Various extraction methods, 0.02–0.04 g sample/mL solventResin656
Br0.40pH 2.5Sealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
0.08pH 9.5
CaNR–56Low pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NR–3.3High pH (≈9)
NR–4.1Ethanol/water
0.26 mg/LWaterSealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventLow-density polyethylene resin423
0.13 mg/LpH 6.8 buffer
0.13 mg/L0.2% Polysorbate 80
0.16 mg/L0.1% EDTASealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventHigh-density polyethylene resin423
0.05 mg/LWater
0.03 mg/L0.1% EDTASealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
<0.01pH 2.5
<0.01pH 9.5
15.6WaterVarious extraction methods, 0.02–0.04 g sample/mL solventResin656
14.1pH 2.5
14.1pH 9.5Sealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
Co0.01pH 2.5
<0.01pH 9.5
<0.005Water, olive oil, 3% acetic acid, ethanolSealed vessel, 40 °C for 10 days, 28 cm2 per 50 mL solventResin, total pool of Co = 50 mg/kg44
Cr0.0023% acetic acidSealed vessel, 40 °C for 10 days, 0.15 g sample/mL solventTotal pool = 3.7 mg/kg21
<0.01pH 2.5Sealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
<0.01pH 9.5
<0.09Water, olive oil, 3% acetic acid, ethanolSealed vessel, 40 °C for 10 days, 28 cm2 per 50 mL solventResin, total pool of Cr = 50 mg/kg44
Cu3.9waterVarious extraction methods, 0.02–0.04 g sample/mL solventResin656
7.7pH 9.5
FeNR–0.12Low pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NRHigh pH (≈9)
NREthanol/waterSealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventLow-density polyethylene resin423
0.02 mg/L0.1% EDTA
0.02 mg/L0.1% EDTASealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
0.12pH 2.5
<0.01pH 9.5
MgNR–0.02Low pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NRHigh pH (≈9)
NREthanol/water
0.0023% acetic acidSealed vessel, 40 °C for 10 days, 0.15 g sample/mL solventTotal pool = 23 mg/kg21
0.28 mg/LWater
0.25 mg/LpH 6.8 bufferSealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventLow-density polyethylene resin423
0.25 mg/L0.2% Polysorbate 80
0.27 mg/L0.1% EDTA
0.03 mg/LWater
0.01 mg/LpH 6.8 bufferSealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventHigh-density polyethylene resin423
0.01 mg/L0.2% Polysorbate 80
0.05 mg/L0.1% EDTA
0.18pH 2.5Sealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
0.04pH 9.5
Mn0.01pH 2.5Sealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
<0.01pH 9.5
NaNR–89Low pH (≈3)
NA2High pH (≈9)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NR–4.0Ethanol/water
0.96pH 2.5Sealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
Ni1.2Water
0.4pH 2.5Various extraction methods, 0.02–0.04 g/mL solventResin656
0.4pH 9.5
PNR–0.76Low pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NAHigh pH (≈9)
NREthanol/water
<0.01pH 2.5Sealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
Pb0.01 mg/LWaterSealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventLow-density polyethylene resin423
0.01 mg/LpH 6.8 buffer
0.01 mg/L0.2% Polysorbate 80
0.01 mg/LWaterSealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventHigh-density polyethylene resin423
0.03 mg/LpH 6.8 buffer
0.03 mg/L0.2% Polysorbate 80
SNR–34Low pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NR–6.3High pH (≈9)
NREthanol/water
Sb<0.004Water, olive oil, 3% acetic acid, ethanolSealed vessel, 40 °C for 10 days, 28 cm2 per 50 mL solventResin, total pool of Sb = 50 mg/kg44
SiNR–5.7Low pH (≈3)
NR–40High pH (≈9)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NR–6.0Ethanol/water
Sr0.01pH 2.5Sealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
<0.01pH 9.5
Ti0.5pH 2.5Various extraction methods, 0.02–0.04 g sample/mL solventResin656
0.5pH 9.5
ZnNRLow pH (≈3)Sealed vessel, 55 °C for 4 days, 0.02–0.1 g sample/mL solvent10 materials tested; resins and parts312
NR–0.11High pH (≈9)
NREthanol/water
0.23 mg/LWaterSealed vessel, 60 °C for 23 weeks, 0.25 cm2/mL solventLow-density polyethylene resin423
0.03 mg/LpH 6.8 buffer
0.03 mg/L0.2% Polysorbate 80
0.05 mg/L0.1% EDTASealed vessel, 121 °C for 1 h, 0.025 g sample/mL solventResin535
0.08pH 2.5
<0.01pH 9.5
<0.52Water, olive oil, 3% acetic acid, ethanolSealed vessel, 40 °C for 10 days, 28 cm2 per 50 mL solventResin, total pool of Zn = 50 mg/kg44
2.0WaterVarious extraction methods, 0.02–0.04 g sample/mL solventResin656
Zr<0.0013% acetic acidSealed vessel, 40 °C for 10 days, 0.15 g sample/mL solventTotal pool = 2 mg/kg21

  • Notes:

  • ↵1 NR = Not reported: not extracted at reportable levels (generally less than 0.01 μg/g).

  • ↵2 NA = Not applicable; element was a component of the extracting solvent.

  • ↵3 Elements that were not extracted in reportable levels included Ag, As, Be, Bi, Cd, Co, Cr, Cu, Ge, Li, Mn, Mo, Ni, Pb, Sb, Se, Sn, Sr, Ti, V, and Zr.

  • ↵4 Elements that were extracted in reportable levels included Cd, Co, Cr, Cu, Fe, Mn, Ni, and V.

  • ↵5 Elements that were not extracted in reportable levels (<0.01 μg/g) included As. Cu, K, Mo, Ni, Pb, Si, Sb, Ti, and V.

  • ↵6 Elements that were not extracted in reportable levels (<0.3 μg/g) included Ag, As. Cd, Co, Cr, Hg, Ir, Mo, Ni, Pb, Pd, Pt, Os, Rh, Ru, Se, Si, Sb, Sn, Ti, and V.