Polychlorinated Biphenyls in the Phthalocyanine Pigments M. Uyeta, S. Taue and K. Chikazawa Kochi Prefectural Public Health Laboratory 2-4-1 Marunouchi, Kochi, Japan 780

In r e c e n t y e a r s there has b e e n c o n s i d e r a b l e p u b l i c c o n c e r n a b o u t the p r e s e n c e of p o l y c h l o r i n a t e d b i p h e n y l s (PCBs) r e s i d u e s in the e n v i r o n m e n t . Many studies have i n d i c a t e d that t h e s e r e s i d u e s r e s u l t e d f r o m the use of c o m m e r c i a l f o r m u l a t i o n s of P C B s in v a r i o u s i n d u s t r i a l application(JENSEN etal. 1969, K O E M A N e t a l . 1969, NISBET etal. 1972, R I S E B R O U G H e t a l . 1968, Z I T K O e t a l . 1971). H o w e v e r , l i t t l e a t t e n t i o n has b e e n g i v e n to the p o s s i b l e p r e s e n c e of P O D s in some o r g a n i c c h e m i c a l s . T h e r e h a v e b e e n some cases w h e r e gas c h r o m a t o g r a p h i c p r o f i l e s , s i m i l a r to the p r o f i l e f r o m c o m m e r c i a l P C B f o r m u l a t i o n s c o n t a i n i n g 5~% chlorine, w e r e d e t e r m i n e d in e x t r a c t s of b l u e c o l o r p r i n t e d on f o o d p a c k a g i n g m a t e r i a l s a n d b l u e c o l o r p r i n t i n g inks. Consequently, we u n d e r t o o k the a n a l y s i s for P C B in the p h t h a l o c y a n i n e p i g m e n t s w h i c h are u s e d as a s o u r c e of the b l u e color. Materials

and Methods

P h t h a l o c y a n i n e p i g m e n t s w e r e m a i n l y s a m p l e d in the a n d O s a k a a r e a s in Japan, f r o m June to D e c e m b e r , ~972 a n d f r o m J u l y to S e p t e m b e r , 1975.

Tokyo

A n a l y s e s for P C B in the p i g m e n t s w e r e c a r r i e d out b y h e x a n e e x t r a c t i o n , F l o r i s i l c o l u m n c l e a n up a n d e l e c t r o n c a p t u r e gas c h r o m a t o g r a p h y . Approximately 100 m g s a m p l e w a s w e i g h e d into a 125 ml E r l e n m e y e r flask, and r e f l u x e d w i t h 50 ml h e x a n e on the s t e a m b a t h for 30 min. T h e r e f l u x e d s o l u t i o n w a s f i l t e r e d t h r o u g h glass f i b e r paper, the f i l t r a t e p l a c e d on a 10 g, 19 m m i.d. F l o r i s i l c o l u m n a n d e l u t e d w i t h 200 ml h e x a n e . The e l u a t e w a s c o n c e n t r a t e d to 5 ml a n d a n a l y s e d b y e l e c t r o n c a p t u r e gas c h r o m a t o g r a p h y . T h e q u a n t i t a t i o n of P C B r e s i d u e s w a s done b y m e a s u r i n g the t o t a l p e a k h e i g h t of the e l e c t r o n c a p t u r e r e s p o n s e for the r e s i d u e a g a i n s t that of K a n e c h l o r 500, a commercial PCB formulation containing 5~ chlorine m a n u f a c t u r e d in Japan. R e c o v e r i e s u s i n g this p r o c e d u r e r a n g e d f r o m 87.6% to 9 5 . 9 % ( a v e r a g e of 92.0~) w i t h s a m p l e s f o r t i f i e d w i t h K a n e c h l o r 500 at 1OO ppm.

417 Bulletin of Environmental Contamination & Toxicology, Vol. 16, No. 4 @ 1976 by Springer-Verlag New York Inc.

Gas c h r o m a t o g r a p h y was w i t h a S h i m a d z u GC ~ B M e q u i p p e d w i t h a 63Ni e l e c t r o n c a p t u r e detector, 2% D C - 2 0 0 on G a s - C h r o m Q in 1.5 m long x 3 mm i.d. glass c o l u m n o p e r a t e d at a c o l u m n temp. of 180~ A determ i n a t i o n of each gas c h r o m a t o g r a p h i c p e a k was c a r r i e d out b y a S h i m a d z u - L K B 9000 gas c h r o m a t o g r a p h - m a s s s p e c t r o m e t e r o p e r a t i n g at an i o n i z i n g e n e r g y of 70 eV, and an a c c e l e r a t i n g v o l t a g e of 3-5 kV. To r e c o n f i r m the p r e s e n c e and the l e v e l s of PCB f o u n d in p i g m e n t s q u a n t i t a t i v e p e r c h l o r i n a t i o n w a s c a r r i e d out as f o l l o w s ( M I D Z U T A N I et al. 1972, A R M O U R 1973). An a m o u n t of s a m p l e to give one to iO ~ g of PCB r e s i d u e w~as p l a c e d in a 20 cm l o n g x I0 m m i.d. glass test tube, and the s o l v e n t c o m p l e t e l y r e m o v e d u n d e r reduced pressure. The r e s i d u e w a s t r e a t e d w i t h 0.5 ml a n t i m o n y p e n t a c h l o r i d e in a s e a l e d glass test tube h e a t e d at 230~ for 2 hrs in an oil b a t h to f o r m the fully chlorinated decachlorobiphenyl. A f t e r w a r d s the c o o l e d r e a c t a n t w a s e x t r a c t e d w i t h 50 ml b e n z e n e . The b e n z e n e s o l u t i o n w a s w a s h e d s u c c e s i v e l y w i t h 30 ml 20% h y d r o c h l o r i c acid, 25 ml 20% t a r t a r i c acid, and two, 20 ml p o r t i o n s of water, d e h y d r a t e d w i t h a n h y d r o u s s o d i u m sulfate, and c o n c e n t r a t e d to 5 ml. D e c a c h l o r o b i p h e n y l f o r m e d b y p e r c h l o r i n a t i o n of a m i x t u r e of c h l o r o b i p h e n y l s w a s e a s i l y d e t e c t a b l e as a s i n g l e p e a k by e l e c t r o n c a p t u r e gas c h r o m a t o g r a p h y u s i n g a 2% D C - 2 0 0 c o l u m n at 220~ Residue values were d e t e r m i n e d b a s e d on the e l e c t r o n c a p t u r e r e s p o n s e to the d e c a c h l o r o b i p h e n y l d e r i v a t i v e compared to s t a n d a r d d e c a c h l o r o b i p h e n y l ; r e s u l t s w e r e e x p r e s s e d in terms of PCB c o n t a i n i n g five c h l o r i n e s . PCB l e v e l s o b t a i n e d b y the two m e t h o d s of q u a n t i t a t i o n , total p e a k h e i g h t and d e c a c h l o r o b i p h e n y l d e r i v a t i v e , w e r e in close a g r e e m e n t . Results

and D i s c u s s i o n

PCB e x t r a c t e d f r o m p h t h a l o c y a n i n e p i g m e n t s of different m a n u f a c t u r e r e s gave gas c h r o m a t o g r a p h i c p r o f i l e s s i m i l a r to a c o m m e r c i a l P C B c o n t a i n i n g 54% c h l o r i n e ; g a s c h r o m a t o g r a m s are s h o w n F i g u r e 1. PCB f r o m p h t h a l o c y a n i n e g r e e n w a s f o u n d to be d e c a c h l o r o b i p h e n y l . E a c h p e a k in the e l e c t r o n c a p t u r e gas c h r o m a t o g r a m s of e x t r a c t s of p h t h a l o c y a n i n e b l u e w a s e v a l u a t e d b y gas c h r o m a t o g r a p h y mass s p e c t r o m e t r y . The n u m b e r of c h l o r i n e s in c h l o r o b i p h e n y l s c a u s i n g the p e a k s w a s f o u n d to be s i m i l a r to that in the c o m m e r c i a l PCB, K a n e c h l o r 500. Decachlorob i p h e n y l in p h t h a l o c y a n i n e g r e e n w a s i d e n t i f i e d in the same m a n n e r .

418

I

2% I)C-200,180 C I.6xIO-I)AFS Before perchlorination 9 ,n

324,Ci-5

]I324

t

m

I 3a~,c~-~ ,

~ ~ ~ ~ I

9 35s c ~ - 6

'

I.

i'

'

Phthlocy-,taine blue

K....hlor 500

Figure

2" DC-'~OO,220-C I I.6x10-gAF. ~ ~!Afterperch[orination i

l ~ ~. ;

tOe~7~hh'el~

P o l y c h l o r i n a t e d b i p h e n y l s in p h t h a l o c y a n i n e blue pigments. T h e m o l e c u l a r ion m / e a n d the n u m b e r of c h l o r i n e s of m a j o r p e a k s w e r e determined by GC-Mass spectrometry.

PCB l e v e l s d e t e r m i n e d in p h t h a l o c y a n i n e p i g m e n t s w e r e b e l o w a p p r o x i m a t e l y 200 p p m as s h o w n in T A B L E i. No PCB w a s d e t e c t e d in some samples. Commercially, two b a s i c p r o c e s s e s are u s e d for the p r e p a r a t i o n of p h t h a l o c y a n i n e p i g m e n t s : ( 1 ) f r o m p h t h a l o n i t r i l e a n d c o p p e r or a c o p p e r salt, a n d (2) f r o m p h t h a l i c a n h y d r i d e , urea, a n d c o p p e r or a c o p p e r salt. The p h t h a l o n i t r i l e p r o c e s s w a s f a v o r e d in Germany, at l e a s t p r i o r to 1945. The u r e a p r o c e s s seems to be f a v o r e d in E n g l a n d , the U n i t e d S t a t e s ( M O S E R et al. 1963) a n d in Japan.

419

1.

TABLE Mean levels phthalocyanine

of

polychlorinated biphenyls blue and phthalocyanine

Makers

of samples, 1972

PCB, p p m av. r a n g e

A

3

90(50-166)

3

B

4

88(66-117)

7

C

2

D

-

-

6

E

-

-

3

F*

2

4(

G*

2

H*

2

I*

2

J*

-

No.

Pigment

Blue

Green

No. of samples, 1975

138(124-151)

3-

~

4)

in green

PCB, p p m av. r a n ~ e

166(132-220) ND 153(142-17~)

42(0.3-110) 0.3(0.2-0.3)

-

-

186(72-300)

-

-

243(186-3o0)

-

-

ND

-

-

-

1

21

64( 60- 68)**

K

2

1

1"*

L*

-

-

1

42**

M*

-

-

2

63(

*imported samples, **decachlorobiphenyl

other are values.

16-110)**

domestic.

PCB was usually found in products produced by the urea process involving trichlorobenzene as t h e r e a c t i o n medium. It is a s s u m e d t h a t s o m e p i g m e n t s f o u n d to c o n t a i n n o P C B w e r e m a n u f a c t u r e d w i t h o u t a s o l v e n t as t h e r e a c t i o n m e d i u m or w i t h a s o l v e n t o t h e r t h a n a n organochlorine s o l v e n t s u c h as t r i c h l o r o b e n z e n e ; for e x a m p l e , nitrobenzene(MOSER et al. 1963) and p o l y a l k y l

benzenes(MATSUURA 1974). No PCB was detected in urea, phthalic anhydride, copper chloride~ ammonium molybdate and trichlorobenzene t h a t a r e u s u a l l y u s e d i n the p r e p a r a t i o n o f p i g m e n t s . P r e c a u t i o n s w e r e t a k e n to a v o i d c o n t a m i n a t i o n o f s a m p l e s by PCBs in our laboratory. Interaction between individual materials and trichlorobenzene was not investigated. However, PCB was found in pigments synthesized by the urea process with trichlorobenzene as t h e r e a c t i o n medium. P C B i n the r e a c t a n t p r o g r e s s i v e l y increased with increased production of phthalocyanine blue. If

420

the p i g m e n t w a s s y n t h e s i z e d u s i n g h y d r o c a r b o n solvents, such as i s o p r o p y l xylene, as the r e a c t i o n m e d i u m no PCB w a s d e t e c t e d in the pigment(MATSUlYRA 197%). The prec u r s o r and m e c h a n i s m of f o r m a t i o n of P C B in the s o l v e n t ( t r i c h l o r o b e n z e n e ) p r o c e s s of p h t h a l o c y a n i n e p i g m e n t p r o d u c t i o n is u n d e r i n v e s t i g a t i o n . T h i s s t u d y i n d i c a t e s that p i g m e n t s p r e p a r e d u s i n g t r i c h l o r o b e n z e n e c o n t a i n PCB. T h e r e f o r e , it m a y be a s s u m e d that the p r e s e n c e of P C B in p h t h a l o c y a n i n e blue was caused by a manufacturing process using trichlorob e n z e n e as the r e a c t i o n m e d i u m . On the o t h e r hand, it m a y be a s s u m e d that d e c a c h l o r o b i p h e n y l in p h t h a l o c y a n i n e green w a s f o r m e d b y p e r c h l o r i n a t i o n f r o m PCB in p h t h a l o c y a n i n e blue. PCBs are a w i d e s p r e a d e n v i r o n m e n t a l c o n t a m i n a n t . Regulatory guidelines have been established and actions taken in Japan. T o d a y t e c h n o l o g y e x i s t s for the manuf a c t u r e of p h t h a l o c y a n i n e p i g m e n t s free f r o m PCB. T h e r e f o r e , it is e x p e c t e d that m a n u f a c t u r e r e s of these p i g m e n t s s h o u l d c o n s i d e r a p p r o p r i a t e m e a s u r e s to e n s u r e that their p r o d u c t s do not c o n t a i n this p e r s i s t e n t contaminant. Acknowledgments We t h a n k J. A. Burke, U. S. F o o d and D r u g A d m i n i s t r a t i o n for m a n y h e l p f u l s u g g e s t i o n s and S. T a k a h a s h i , S h i m a d z u S e i s a k u s h o LTD., for G C - M a s s s p e c t r o m e t r y . References

ARMOUR, J . A . : J . A s s o c . O f f . A n a l . C h e m . , 5 6 , 987 (1973) JENSEN, S . , JOHNELS, A. ft., OLSSON, M. and OHERLIND, ft.: Nature, 224, 247 (1969) KOEMAN, J . H., t e n NOVER de BRAUW, M. C., and de VOS. R. H . : N a t u r e , 221, 1126 (1969) NATSUURA, R . : J a p a n P a t e n t , ~ - 1 1 6 1 2 1 , N o v e m b e r 6, 197~ MIDZUTANI, T. a n d NATSUMOTO, S. :SHOKUHIN EISEIGAKU ZASSHI, 13, 398 ( 1 9 7 2 ) MOSER, F . H. a n d THONAS, A. L . : P h t h a l o c y a n i n e Com pounds, New Y o r k : R e i n h o l d P u b l i s h i n g Corporation, 1963 N I S B E T , I. C. T. and SARFIM, A. F . : E n v i r o n . H l t h Persp., 1, 21 (1972) R I S E B R O U G H , R. W.~ RICHE, P., P E A K A L L , D. B., H E R M A N , S. G. and K I R V E N , M. N. :Nature, 220, 1098 (1968) ZITKO, V. a n d CHOI~ P. M . : F i s h . Res. B o a r d Canada, Tech. R e p o r t No. 2 7 2 , (1971)

421