Mercury, methyl-mercury and selenium in scalp hair of inhabitants from Mediterranean areas

Mercury, methyl-mercury and selenium in scalp hair of inhabitants from Mediterranean areas

Chemosphere, Vol.16, No.4, P r i n t e d in G r e a t B r i t a i n MERCURY, pp 877-886, 1987 0 0 4 5 - 6 5 3 5 / 8 7 $ 3 . 0 0 + .OO P e r g a m...

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Chemosphere, Vol.16, No.4, P r i n t e d in G r e a t B r i t a i n

MERCURY,

pp

877-886,

1987

0 0 4 5 - 6 5 3 5 / 8 7 $ 3 . 0 0 + .OO P e r g a m o n J o u r n a l s Ltd.

M E T H Y L - M E R C U R Y AND S E L E N I U M IN SCALP HAIR OF I N H A B I T A N T S FROM M E D I T E R R A N E A N AREAS +

M.Dermelj, M.Horvat, A.R.Byrne, P.Stegnar "J.Stefan" Institute and Faculty of Natural Sciences and Technology, "E.Kardelj" University, 610OO Ljubljana, Yugoslavia

ABSTRACT In this article the concentrations of Hg, Me-Hg and Se in scalp hair of persons from different geographical areas with different dietary habits, determined by the use of cold vapour atomic absorption spectrometry (CVAAS), radiochemical neutron activation analysis (RNAA) and gas chromatography (GC), are described.

INTRODUCTION Scalp

hair

exposure, trations fluids,

of

the

attracted

trace

its

exposure On

has

nutrition

ease

over

other

behaviour

elements

periods hand,

use

cosmetic

dirt

contamination

may

factor

studies

recently

earlier

problems

involved

as an

ditions

population Blood, bolic

can

survey

which status,

storage,

or m o n t h s

be the but

optimism and

(8),

property

Nevertheless, indicator

is the

prime

is m o r e

material

extensively

of

(9) and

of

trace

body

concen

organs

and

integrator

of

as an

studies

about

elements or

of

s o u r c e s such

not

is an

into

the

ex-

of e n v i -

body. of

usefulness under

the

this

interfering

assesment

the and

least,

cases

indicator

ingestion,

Thus the of

certain

certainly

con-

for

(ll).

individual

used

from but

In c e r t a i n

realistic

of t h e s e

properly

877

ion e x c h a n g e - l i k e

last

elements

to a m o r e

+Dedicated to the memory of Prof.L.Kosta (1921-1986)

its

of s i t u a t i o n s ,

to g e n e r a l i z e

is one for

(lO).

interest

for c e r t a i n

and

elevated

as an

contamination

sweat

of e x p o s u r e

Mercury

to o t h e r

property

particularly

in the m a j o r i t y

way

of e n v i r o n m e n t a l

favourably

(i-3).

preparations

has g i v e n

purposes.

its

to e x t e r n a l

dust

it is d i f f i c u l t

be g o o d

fields

of the

and

of hair,

c o n n e c t e d with i n t a k e s

indicator.

hair

and

in the

because

it contains r e l a t i v e

and

pharmaceutical

contamination,

hair

which

it s u s c e p t i b l e

ronmental in

health

properties

(7),

and

investigators

of w e e k s

the

(4-6),make

atmosphere

ternal

many public

of s a m p l i n g

as the of

and

for

such

exposure

and

purposes

than

metahair

878

However, hair

for m e a s u r e m e n t

as an i n t e g r a t i n g

invasive

sampling.

centration Provided

in hair

external

it has been

shown

to that

from

with

Some

ption

than

other

mercury

population the hair

largely

groups.

the Y u g o s l a v

Hg,

Me-Hg

coasts

were

(CVAAS),

entirely of magni-

different

hair

deter-

gas-chroma-

(RNAA),

to c o r r e l a t e

at risk

con-

(15).

analysis

by e x a m i n i n g

to be possibly

and Greek

almost

two orders

spectrometry

activation

non-

of mercury

and Se in scalp

One of the aims was

concentrations considered

contain

of exposure, offers

at 2OO-300:i(2,12-14).

as m e t h y l m e r c u r y

absorption

neutron

the ratio

constant

in hair arises

which

for total

vapour

and r a d i o c h e m i c a l

populations

from

foods,

results

the use of cold

different

ons.

is absent,

or as a record and of course

that

is r e l a t i v e l y

of fish or shellfish,

we present

(GC)

sumption

in blood

exposure

more m e r c u r y

with

of time

Importantly

tude

tography

periods

to blood,

the c o n s u m p t i o n

mined

longer

is s u pe r i o r

from

In this work,

over

monitor

obtained fish

con-

geographical

from

high

regi-

fish consum-

included.

EXPERIMENTAL

i. C o l l e c t i o n For

and

preparation

comparatibility

metals

in scalp

cedures rial

of results

hair,

are very

proposed

(16-18).

(18,19),

that

In our work and with

To remove

different

It apears

mercury

to estimate

their

A represents

gible

fish

Other

of i n h a b i t a n t s

which

area

project

which MED

of sea

near

Zadar

(group

are

a some taken

POL Phase

II.

the

areas

village D),

plant)

of the hair from

people

Subjects

per week Hungary,

with

small

for Hg, with

from a coastal

area

(group

of i n h a b i t a n t s

regions were

asked

(see Table with

and

weekly

on the island

programme

on w a s h i n g

fish

Se in the fish

of Cres where

I).

a negli-

to m o d e r a t e

Me-Hg

higher

is elevated

samples

research

eaten

been

lost.

geographical

with

leaching

have

of e l e m e n t s

analysed.

pro-

of the mate-

minimal

not

heavy

cleaning

samples

and

from different

the values

with

hair

in the hair,

the border

on trace

and

the surface

contamination

food were

from coastal

from a fishing

from

of the removal

B are urban

represent

of data

protocols

for w a s h i n g

as fish meals

near

(due to a c h l o r a l k a l i

represents

coast,

results

for example,

from an urban

studies retained

group

Group

hair

Hg emission

surface

consumption

consumption.

sumption,

contaminants

of i n h a b i t a n t s

a rural

consumption.

samples

from

consumption fish

Group

collection

procedures

is largely

hair samples

different

hair

of external

important.

material

and valid interpretation

appropriate

for e l i m i n a t i o n

of internal

of samples:

con-

(group

C),

industrial

E),

and group

from

the Greek

of the W H O / F A O / U N E P

F,

joint

879

Hair samples were cut with stainless sites,

preferably

in the occipital

steel scissors or a trimmer from several

area as close as possible

then cut into 2-5 mm segments and cleaned a c c o r d i n g tion

to the scalp and

to the IAEA ~ e c o m m e n d a -

(20,21).

2. D e t e r m i n a t i o n Determination

of total Hg and Me-Hg by the use of CVAAS and GC

of total Hg by CVAAS was carried out following the p r o c e d u r e of

Mc Mullin et al. (22), while Me-Hg was determined method

by a partly m o d i f i e d West66

(23).

Total Hg bF CVAAS

Me-Hg by GC

Wet destruction of the sample with

Digestion of the sample with NaOH solution (7.5M NaOH, 30 min, 90°C)

H2S04, ~NO 3 and H202 under reflux

! Reduction of the resulting solution with

Extraction of Me-ttg into toluene

Snil 2 Stripping of the organic phase with O.1M

Peak height measurement of aerated

Na2S203 solution

elemental Hg with LDC UV Monitor Model 1205.

Reextraction of Me-Hg into benzene (2M H2S04, 4M KBr)

Injection of the organic phase into chromatographic column 1 = 1.6m; 0 = 0.2 nml; carrier gas: N2; stat.pH.: 5 % PEGS on Chromosorb W

Detection of Me-Hg using Hewlett-Packard GC M5750 with EC detector

Determination Irradiation Institutes was

of total

of the sample TRIGA MARK

Hg and

Se by RNAA

in plastic

II Reactor

tubes

together

at a flux

with

standards

in the

of 2 . 1 o l 2 n . c m - 2 s -I for 20-40

hours

performed.

Selenium (26)

Mercury and Selenium (24r25)

Destruction of the sample with saturated

Same aliquot

Mg(NO3)2, heating on sand bath; then 30 min Pyrolysis of the sample

at 550°C in oven

Dissolution of fusion cake in 6M HCI,

Volatilization

L

Hg

I

heating for 10 min, reduction Se(VI)--~Se(IV)

Be

I

Trapping Hg vapour

2 ml i% 4 NDP (-nitro-o-phenylene-diamine)

Trapping as SeO 2

by formation of HgSe

warm iO min, extraction with CC14

on soda lime

I

I

Measurement of corresponding garmna activity of isolated radionuclides on a "3x3" NaI/TI well type detector connected to 400 channel analyser

197Hg (TI/2 75Se (TI/2

65 h; E~ = 0.077 MeV) 12Od;

E~ = O.121; O.136; 0.264; 0.280; 0.400 MeV)

RESULTS AND DISCUSSION Apart that

from o c c u p a t i o n a l l y the c o n s u m p t i o n

The greater of highly Expert rable

part

toxic

of mercury Me-Hg

Committee weekly

present

intake

as Me-Hg. sea

region

has been

mainly

organised

and

account

its

food

possible

in such

and

when

this

point

together

studies.

also

food

recognized

it recommended

IAEA.

(27)the

health

In view

function

be one of the

than

FAO/WHO

be

in

on the p o p u l a t i o n activities,

of the e s s e n t i a l i t y

factors

tole-

200 ug should

inernational

to Hg toxicity,

form

provisional

of Hg and Me-Hg

effects

time

to mercury.

is in the

by the Joint

no more

of c o n s i d e r a b l e

for a long

of man

products

determination

potential

known

of exposure

sea

Hg of which

FAO and

antagonistic

should

other

of view,

with

the subject

it has been

source

This was

Additives

by the WHO,

of s e l e n i u m

in fish

of 300 ug total

From

of the

levels

individuals,

is the main

compounds.

on Food

Mediterranean

nium

exposed

of fish

of sele-

concentration

to be taken

into

special

881

In order

to help

inland and to o b t a i n

partly

coastal

areas

possible

geographical

elucidate

pollution

m o n i t o r i n g and

results

ratio

(Table

in scalp

region.

Hg to Me-Hg

the scalp

consumed

of total

levels

and Se,

(MED.POL.

Hg, M e - H g

locality

amounts

for

Fhase

and

II).

their

and g e o g r a p h i c a l

of sea

Hg and Me-Hg are very

This

term p r o g r a m m e

Sea

of total

minimal

was a n a l y s e d

Hg, M e - H g

p o p u l a t i o n groups.

c o n n e c t e d with

from

food

low and

(group

the ratio

A), of

is high.

slightly

what

levels

of Greece

of a long

in the M e d i t e r r a n e a n

show v a r i a t i o n s

In a p o p u l a t i o n which

areas

of these

framework

I) for c o n c e n t r a t i o n

hair

the c o n c e n t r a t i o n

The

research

the

hair of p e r s o n s

the levels of total

type of n u t r i t i o n

in part p e r f o r m e d w i t h i n

scalp

and coastal

between

study was

The

question,

of Y u g o s l a v i a

correlations

region and

this

increased

concentration

hair of i n h a b i t a n t s

higher

consumption

levels

of L j u b l j a n a

of sea

of Me-Hg and Hg and (group B) are

food p r o d u c t s

their

probably

and p o s s i b l e

ratio

due

in

to some-

higher o c c u p a t i o n a l

exposure. The e l e v a t e d

concentration

from the Y u g o s l a v form of Me-Hg, shellfish Only

one

mercury ptoms

The

and

and

that

selenium

is not

total

in this

groups most

over

is in the

consumption

of fish,

study

(No.8,

Group

the onset

a risk,

mercury),

while

the whole

best way

of those

at more

F) had a hair

of t o x i c o l o g i c a l

of such

which

studies

requires

worker

of Me-Hg); Hg in the

sym-

is the

iden-

extensive

field

the c o n c e n t r a t i o n

the a c c u r a c y

of SRMs

element cr CRMs

analysis (Standard

and

from

of s e l e n i u m

or C e r t i f i e d

not mean

in hair

They are

of sea

food

his o c c a s i o n a l

(fluctuations

precision

does

selenium

(M.D.).

fraction

is to apply

the coastal

in the body.

Me-Hg and

reflect

laboratory

both

This of course

sites

with a minor

to control

analyses

active

they also

of sampling.

in trace

constant.

from the same person

period

obtained

examined,

for total mercury,

4 years

of a l a b o r a t o r y

to i n o r g a n i c

hair

is p r a c t i c a l l y involved

the results

collected

(low p e r c e n t a g e

during

all m e r c u r y

to that at which

of scalp

from inland,

sentative

The

content

II shows

exposure

where

analyses.

area

diet

almost

to the higher

One of the d i f f i c u l t i e s

of the critical

selenium

samples

areas,

attributed

of the p o p u l a t i o n

sea products.

close

be expected.

of Hg in the scalp hair

coastal

of the subjects e x a m i n e d concentration

might

Table

and Greek

can be d i r e c t l y

and other edible

tification work

levels

in his

professional

in c o n c e n t r a t i o n

is p r a c t i c a l l y

of a n a l y t i c a l

the m e t h o d s Reference

repre-

used

of

constant

results to the

Materials)

and

to

~82

Table I.

Total Hg, M e - - H g a ~

Se in hair of persons from diffex.mat

Mediterranean areas and controls

Sampling point and code number

Sex

Age

Fish consumed meals/week

Hg total (~g.g-l) NAA CVAAS

Me-Hg (ug.g-l)

Se i (~g.g-)

A

1 2 3

f f f

21 20 34

O 0 O

0.26 0.45 0.45

0.27 0.42 0.23

O.O1 O.O1 O.O1

0.29 0.22 0.35

B

i 2 3 4 5 6

m f m m f m

26

1 O i O 0 2

0.27 0.42 1.04 0.30 0.81 0.83

0.24 O.41 1.O4 0.48 0.81 0.80

O.15 O.12 0.39 O.16 0.06 0.55

0.29 0.22 0.29 0.68 O.71

C

1 2 3

f m m

62 72 60

5 5 3

-

9.89 2.65 3.46

1.42 0.94 1.OO

0.73 O.41 0.36

D

1 2 3 4 5 6

m m m f f f

48 42 59 30 28 39

2 3 0 2 2 2

8.32 i0.O 0.53 0.99 1.40 0.84

0.46 1.14 1.40 0.90

8.74 9.78 0.39 0.72 1.90 0.87

0.58 0.58 0.30 0.40 0.37 0.40

E

1 2 3 4 5 6 7

m m m m m m m

69 54 58 60 60 47 48

3 2 2 2 3 2 1

1.S1 4.47 0.87 5.36 5.11 1.76 2.1

-

1.49 3.67 0.62 4.67 5.06 1.41 1.97

O.41 0.37 0.42 0.52 0.37 0.42 0.42

F

i 2 3 4 5 6 7 8 9 IO

f f m f f m m m m m

14 14 13 14 40 20 20 20 20 20

2 3-4 2 2 2-3 7 3-4 7 4 7

1.14 1.43 1.40 3.00 1.06 3.80 1.40 37.5 2.74 2.60

-

1.14 1.43 1.O6 1.81 0.88 2.70 1.11 36.0 2.30 2.5

0.39 0.38 0.40 0.44 O.41 0.35 0.56 0.74 0.52 0.47

Note:

A

Controls (a village, northeast Slovenia), negligible fish consumption

B

Controls (Ljubljana), small to moderate fish consumption

C

Volunteers from the fishing village on the island Cres

D

Coastal area near Zadar

E

Coastal area where industrial Hg emission is high (Split)

F

Scalp hair of persons from Greek coastal areas

883

Table II.

Variations of the total mercury, methyl-mercury and selenium concentrations in the hair of a laboratory worker (50 y., m) as a function of time

No. of sample

Date of sampling

Hg - total ug.g -1

Me - Hg ~g.g -1

Se ~g.g-i

1

Jan. 81

1.27

O.16

0.39

3

April 81

0.86

0.24

0.40

6

May 81

0.78

O.13

0.68

9

Aug.S1

0.34

O.14

0.40

12

Oct.81

0.36

0.20

0.62

15

Jan.82

0.42

O.13

0.55

18

April 82

0.83

O.13

0.48

21

July 82

1.Ol

O.14

0.44

24

Sept.82

1.23

O.17

0.48

27

Jan.83

0.54

O.21

O.41

30

March 83

0.47

O.16

0.50

33

June 83

0.35

O.12

0.40

36

Aug.83

0.44

O.14

0.47

39

Nov.83

0.43

O.17

0.38

42

Feb. 84

0.37

O.17

0.40

45

April 84

0.34

O.15

0.34

48

June 84

0.33

O.17

0.45

50

Aug.84

0.49

O.14

0.33

52

Oct.84

0.88

0.16

0.50

54

Dec.84

O.41

O.15

0.40

884

compare and

the results

obtained

reproducibility

analysis values

of SRMs.

(Table

At present (or other

showed

procedure

control.

checked

with

mendation

used

MeHgCN,

Medicine

on a filter

extraction

with

laboratories Table the

analysed

IV the a g r e e m e n t

matic

then

error

for Me-Hg

by other

means

certified of

in hair of a n a l y t i c a l

by GC d e t e r m i n a t i o n

laboratory

according

project

MED.POL.Phase the L a b o r a t o r y

Stefan

involved

Institute.

the d e s t r u c t i o n

the biological with

the results

is evident,

and

of Me-Hg

dishes.

sample

cisteine

sample

using

obtained this

II

normal

(28).

of Legal techique

of biological

The

resulting

in the d i f f u s i o n and

chromatography

from

The

was

to the reco-

in both

the i n t e r l a b o r a t o r y

in the d e t e r m i n a t i o n

Se with

by the

the r e l i a b i l i t y

joint

by the use of gas

methods

is a v a i l a b l e

K4Fe(CN) 6 in Conway

from

Hg and hence

The a c c u r a c y

checked

analysed

impregnated

between

and

of Me-Hg

in our

Laboratory

paper

benzene

two d i f f e r e n t

material

of the Jo~ef

is v o l a t i l i z e d

is trapped

for total

values. were

work.

of analysis

was

in this work

agreement

in the W H O / F A O / U N E P sample

or l i t e r a t u r e

has to be assured

by the use of H2SO 4 and which

results

prepared

the L a b o r a t o r y

by the Legal

ma t e r i a l

reference

sample

described

and

of our

The a c c u r a c y

a hair

obtained

satisfactory

and a c c u r a c y

interlaboratory

Me d i c i n e

certified

for routine

no c e r t i f i e d samples),

quality

This

Comparison

III)

the m e n t i o n e d

with

of the results

determined

(29,30).

both

However,

techniques.

in the two

both

From

laboratories

the p o s s i b i l i t i e s

can be p r a c t i c a l l y

cell,

after

by

of syste-

eliminated.

ACKNOWLEDGEMENT

We a c k n o w l e d g e funding

the

this work.

of the a n a l y s e s

financial Thanks

referred

support

are also to in this

of the Research

due

to Miss

paper.

Community

A.Prosenc

of S l o v e n i a

for c a r r y i n g

out

for part

Table III. Results for total Hg and Se in S F ~ c o R ~

~rith certified values (31-33)

Total Hg Sample

CVAAS

NAA

ng/g NBS SRM 1566 Oyster Tissue

Selenium Pyrolysis

ng/g

60.7~4.0

Certified values

4 - NDP

~g/g

48.1~5.1

ug/g

2.62~O.2

57Z15

2.0830.09 2.1~O.5

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

NBS SRM 1572 Citrus Leaves

81.6~7

82.2~4.2

Certified values

0.053~0.02

80~2.O

(0.025)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

NBS SRM 1577A Bovine Liver

5.5~2.0

Certified values

3.4~0.5

0.5730.06

432

O.71~O.O4 O.71~O.07

Note: Results and standard deviations refer to 4 to 6 aliquots analysed. Certified values in parentheses are for information only

Table IV.

Results for Me-Hg in the interlaboratory hair sa~le (~4~/g)

Institution

Isolation on the basis of extraction

Isolation on the basis of diffusion

Laboratory of Legal Medicine

~91 3 12

(n : 14)

522 3 26

(n = 20)

Laboratory of IJS

586 ~ 16

(n = 12)

545 ~ 29

(n = 12)

Note:

n - number of determinations

LITERATURE

i. C.PANKHURST,

B.D.PATE:

2. D.W.JENKINS:

"Toxic

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