4.2 M. Bader

14
Results and implications of a longitudinal biomonitoring study on mercury exposure Michael Bader 1 , Sandra Brill 1 , Axel Schlieter 1, Christoph Uebler 2 , Josef Guth 2 1 BASF SE, Occupational Medicine & Health Protection, 67056 Ludwigshafen, Germany 2 BASF SE, Electrolysis I, 67056 Ludwigshafen, Germany 1 Occupational Medicine & Health Protection Chief Medical Officer: Dr. med. Stefan Lang

Transcript of 4.2 M. Bader

Page 1: 4.2 M. Bader

Results and implications of a longitudinal

biomonitoring study on mercury exposure

Michael Bader1, Sandra Brill1, Axel Schlieter1, Christoph Uebler2, Josef Guth2

1 BASF SE, Occupational Medicine & Health Protection, 67056 Ludwigshafen, Germany 2 BASF SE, Electrolysis I, 67056 Ludwigshafen, Germany

1

Occupational Medicine & Health Protection

Chief Medical Officer: Dr. med. Stefan Lang

Page 2: 4.2 M. Bader

2

Inorganic Mercury

CNS impairment

kidney damage

inhalational

uptake

~ 80 %

gastrointestinal

resorption

< 0.01 %

dermal

absorption

~ 2 %

t1/2 ~ 40 days

cold vapour AAS

EU 20 µg/m3

Germany 20 µg/m3

US-ACGIH 25 µg/m3

US-NIOSH 50 µg/m3

© iStockphoto.com/Triton21

Page 3: 4.2 M. Bader

3

Correlation between airborne and urinary mercury

Bender et al. 2006

Gefahrstoffe – Reinhaltung der Luft 66:465-468

Central conclusion:

The assessment of the health hazard of

exposed workers should rest upon the deter-

mination of mercury in urine, and not on the

concentration of mercury in workplace air.

Surveillance of 23 workers from 8 plants:

mercury in workplace air (PAS, 8-h-TWA, n = 44)

urinary mercury (postshift, n = 33)

mercury in air (µg/m3)

mercury in urine (µg/g crea.)

r = -0.030

p = 0.890

Page 4: 4.2 M. Bader

4

HBM assessment values for urinary mercury

category remarks value unit

reference value w/o dental amalgam 1 µg/L

HBM-I value observation level 5 µg/g crea.

HBM-II value intervention level 20 µg/g crea.

category remarks value unit

DFG BAT 1982 200 µg/L

DFG BAT 1998 100 µg/L

DFG BAT 2005 30 µg/L

SCOEL BLV 2007 30 µg/g crea.

DFG BAT 2007 25 µg/g crea.

BGW 2012 25 µg/g crea.

ACGIH BEI 2013 20 µg/g crea.

Page 5: 4.2 M. Bader

electrolytic cell

graphite anodes

amalgam decomposer

pump

sodium amalgam mercury

cathode

5

Chloralkali Electrolysis

http://commons.wikimedia.org/wiki/File:Chloralkali.svg

Page 6: 4.2 M. Bader

6

Chloralkali Electrolysis Cell Room

Mercury used in chloralkali cells

European Union 5952 tons

Germany 1676 tons

BASF Ludwigshafen 734 tons

www.eurochlor.org (2012)

© B

AS

F S

E –

Occupation

al

Medic

ine &

Health P

rote

ction

Page 7: 4.2 M. Bader

7

Study group

no. of employees job category mercury exposure sampling frequency

184 production always low (semi)annually

22 maintenance infrequently

& moderate quarterly

9 cleaning frequently

& significant monthly

- 214 male employees from an alcoholates production plant

- regular biomonitoring since 1989

- comprehensive biomonitoring program since 2010

- experience and summary of the first three years

Page 8: 4.2 M. Bader

8

(Semi)annual sampling: production

month of sampling & number of samples

µg mercury/g creatinine

BAT

BEI

Page 9: 4.2 M. Bader

9

Quarterly sampling: maintenance

month of sampling & number of samples

µg mercury/g creatinine

Page 10: 4.2 M. Bader

Monthly sampling: cleaning

month of sampling & number of samples

µg mercury/g creatinine

frequent safety instructions

(gloves, trouser pockets, etc.)

daily change of working clothes

job rotation

10

Page 11: 4.2 M. Bader

Aggregated results

routine maintenance cleaning

employees (n) 184 22 9

samples (n) 531 83 231

median (µg/g crea.) 2 6 16

95 % (µg/g crea.) 8 23 30

% BAT 0 4 13

cleaning 2010 2011 2012

samples (n) 77 81 73

median (µg/g crea.) 18 18 15

95 % (µg/g crea.) 38 31 22

% BAT 18 19 3

11

Page 12: 4.2 M. Bader

month of sampling

µg mercury/g creatinine

job rotation

Individual follow-up: three examples

12

t1/2 ~ 40 days

Page 13: 4.2 M. Bader

13

Individual follow-up: job change and job entry

month of sampling

µg mercury/g creatinine

job rotation beginners

Page 14: 4.2 M. Bader

14

Summary and conclusions

- The terminal half-life (t1/2) of a compound should be considered.

- Biomonitoring, not air monitoring, is the current tool of choice for the analysis

and assessment of occupational mercury exposure inside BASF SE.

- Mercury exposure is under frequent control and generally below the German BGW/BAT.

- The intensity of exposure is a criterion for the selection of the monitoring frequency.

- Individual excursions trigger temporary job rotation and renewed safety instructions.