11.3 Smolders

16/10/2013

Inter‐ and intra‐individual variability in biomarker values over a continuous six‐day sampling period

Funded by:

16/10/2013 2© 2013, VITO NV

Introduction t1/2

Exposure frequency

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Introduction t1/2

Exposure frequency

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Project outline

» CEFIC‐HBM4 project structure

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Project results

» WP3: Human Biomonitoring study

An HBM study will be set up to provide fit‐for‐purpose data for validation ofthe TK‐model. A small number of participants will be asked to collect all urinevoids over the period of a week. Biomarker data will be used to identify howurine collection frequency affects the determination and interpretation ofbiomarker measurements, and to propose optimal sampling strategies infunction of chemical specific characteristics.

16/10/2013 6© 2013, VITO NV

WP3: Human biomonitoring study

» Outline:» 8 individuals were recruited» All urinations were completely collected over a six‐day period» Exposure to personal care products (PCPs) was targeted» Diary with information on food consumption and use of personal care

products (at 30 minute intervals)» Biomarkers included:

» 4 Metals (As, Cd, Mn, Ni)» 15 Organic compounds (9 parabens, triclosan, triclocarban, Benzophenon 1‐3‐8, BPA)

» Creatinin, specific gravity

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» Outline:» Exposure to PCPs was based on the ingredient list published on

packages:

Day creamToothpaste

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» Exposure to personal care products (PCPs):» Intake moment: inventory of personal care products used» Two sets of products:

» Containing target substances (D‐2 to D1 and D4 to D6)» Free of target substances (D2 and D3)

Product use with target substances

Product use without target substances

Urine collection

16/10/2013 9© 2013, VITO NV


» Activity diary:» Included application of PCPs and food consumption

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Participant 1

Participant 2

Participant 3

Participant 4

Participant 5

Participant 6

Participant 7

Participant 8

Gender Female Male Female Male Female Male Female Male

Age 31 38 31 40 58 58 66 66

Length (cm) 170 190 167 184 172 189 163 178

Weight (kg) 58 92 57 85 66 95 63 78

Profession TeacherCivil

servant

Quality control manager

Civil servant

Civil servant

Civil servant

Retired Retired

Smoking No No No No No Yes No NoDietary

supplementsNo No No No Yes No No No

Participant 1

Participant 2

Participant 3

Participant 4

Participant 5

Participant 6

Participant 7

Participant 8


Age 31 38 31 40 58 58 66 66

Length (cm) 170 190 167 184 172 189 163 178

Weight (kg) 58 92 57 85 66 95 63 78


servant

Qualitycontrol manager

Civil servant

Civil servant

Civilservant

Retired Retired



Participant 1

Participant 2

Participant 3

Participant 4

Participant 5

Participant 6

Participant 7

Participant 8


Age 31 38 31 40 58 58 66 66

Length (cm) 170 190 167 184 172 189 163 178

Weight (kg) 58 92 57 85 66 95 63 78


servant


Civil servant

Civil servant

Civil servant

Retired Retired



Participant 1

Participant 2

Participant 3

Participant 4

Participant 5

Participant 6

Participant 7

Participant 8


Age 31 38 31 40 58 58 66 66

Length (cm) 170 190 167 184 172 189 163 178

Weight (kg) 58 92 57 85 66 95 63 78


servant


Civil servant

Civil servant

Civil servant

Retired Retired




» 8 individuals participated

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» Urine collection parameters» In total, 352 samples (not one reported missing, 1 sample incomplete)

Participant 1

Participant 2

Participant 3

Participant 4

Participant 5

Participant 6

Participant 7

Participant 8

# Samples 43 46 40 45 65 34 39 40

Total volume (g) 7748,1 13987,8 7621,4 21047,5 10273,7 8244,9 12541,9 11101,1

Smallest sample (g) 15,8 73,3 40,4 82,9 6,0 93,4 21,4 67,4

Largest sample (g) 774,8 827,7 408,1 986,3 450,6 372,3 781,9 627,0

Size ratio (L/S) 49,0 11,3 10,1 11,9 75,1 4,0 36,5 9,3Avg urine flow rate(g/kg b.w./hour)

1,04 1,38 1,19 2,41 1,29 0,68 1,41 1,21

Urine flow rate ratio (L/S)

24,5 12,4 11,7 16,1 90,1 6,2 15,4 10,8

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» Biomarker measurements ‐Metals:» Arsenic (t1/2 ≈ 4 days*) At 18:00

Scampi’s for dinner

* Hughes (2006)

Hours since start collection

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» Biomarker measurements – Metals» Cadmium (t1/2 ≈ 6‐38 years*) – Environmental exposure, smoking

» Clear diurnal cycle in Cd‐excretion…

* ATSDR (2008)

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» Biomarker measurements – Metals» Cadmium – diurnal pattern

0:00-6:00 6:00-10:00 10:00-14:00 14:00-18:00 18:00-0:00

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» Biomarker measurements – Organic components» 15 different biomarkers measured

Parabens Benzophenones Others

Compound % < LOQ(range)

Compound % < LOQ Compound % < LOQ Compound % < LOQ

Methyl (LOQ=0,5 µg/l)

0,0 %(0,0 % – 0,0 %)

Butyl(LOQ=0,5 µg/l)

73,9 % BP 1(LOQ=0,5 µg/l)

86,6 % Bisphenol A(LOQ=0,5 µg/l)

26,2 %(1,1 % – 52,9 %)

Ethyl(LOQ=0,5 µg/l)

6,8 %(0,0 % – 31,1 %) Benzyl

(LOQ=0,5 µg/l)95,7 % BP 3

(LOQ=0,5 µg/l)

29,8 %(0,0 % – 91,2 %) Triclosan

(LOQ=0,5 µg/l)

20,5 %(0,0 % – 93,3 %)

Iso‐propyl(LOQ=0,5 µg/l)

100 % Pentyl(LOQ=0,5 µg/l)

100 % BP 8(LOQ=0,5 µg/l)

100 % Triclocarban(LOQ=0,5 µg/l)

100 %

Propyl(LOQ=0,5 µg/l)

29,3 %(0,0 % – 76,5 %) Heptyl

(LOQ=0,5 µg/l)100 %

Iso‐butyl(LOQ=0,5 µg/l)

100 %

16/10/2013 16© 2013, VITO NV


» Biomarker measurements – Organic components» Methylparaben exposure

Day cream(D0, 22:30)

Day cream(D4, 7:00)



Day cream + shower gel + body lotion(D5, 16:30)

Hours since start of urine collection

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» Biomarker measurements – Organic components» Methylparaben exposure


Day cream(D4, 7:00)



Day cream + shower gel + body lotion(D5, 16:30)

Shampoo + conditioner + day cream + showergel(D6, 8:30)

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» Biomarker measurements – Organic components» Triclosan exposure

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» Biomarker measurements – Organic components» Triclosan exposure

» Effect of toothpaste brand !time lag time lag

* Sandborgh‐Englund et al, 2006

10-fold decline over 42 hours ~ 12.5 hr HL, similar to 11h in literature*

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» Inter‐ versus intra‐individual variability» Log‐transformation measurements» One‐way random effects ANOVA

» ICC < 0,4 ≈ poor reproducibility» 0,4 < ICC < 0,75 ≈ fair to good reproducibility» ICC > 0,75 ≈ excellent reproducibility

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» Biomarker measurements – Metals» Inter‐ versus intra‐individual variability

Arsenic Cadmium Manganese Nickel Creatinin Specific gravity

Expressed as ng/l

Between individual variability 5,26 28,13 24,49 6,60 10,38 0,0039

Within individual variation 45,40 32,97 121,9 31,89 40,98 0,0199

ICC 0,104 0,460 0,167 0,207 0,253 0,196

Expressed as ng/g creatinin

Between individual variability 6,25 20,24 29,18 14,47

Within individual variation 24,25 6,76 74,92 6,87

ICC 0,205 0,750 0,280 0,678

16/10/2013 22© 2013, VITO NV


» Biomarker measurements – Metals» Inter‐ versus intra‐individual variability

» High ICC for Cadmium…

58-66 years

30-40 yearsNg/l Ng/g creatinin

8 participants 0,460 0,750

Age 30‐40 0,219 0,075

Age 58‐66 0,407 0,328

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» Biomarker measurements – Organic compounds» Inter‐ versus intra‐individual variability

BPA: ICC = 0.15Methyl paraben: ICC = 0.52Triclosan: ICC = 0.92

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Conclusions

» Analyses still in progress» Use of PCP containing target analytes can be detected in urinary

profiles» In many cases rapid rise and subsequent decreases

» Factors influencing variation in spot sample concentrations:» Intra‐individual

» Elimination half‐life in relation to intervals between exposure events» Variation in exposure rates

» Inter‐individual» Variation in exposure rates

16/10/2013 25© 2013, VITO NV

Acknowledgments

» The 8 participants: for collecting urine, carrying around empty and full jars, and filling in the questionnaires;

» The project team: » HSL (UK): Nick Warren, Kevin McNally, John Cocker, Kate Jones» Summit Toxicology (USA): Sean Hays, Lesa Aylward, Chris Kirman» Cranfield University (UK): Len Levy, Ruth Bevan» IPA ‐ Ruhr‐University of Bochum (DE): Holger Koch

» CEFIC: for financial support under the Long Range Initiative (CEFIC‐HBM4)

Health & Medicine

11.3 Smolders