Effect of Acetone on the Toxicity of Four Chemicals to Selenastrum Capricornutum

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  • 8/3/2019 Effect of Acetone on the Toxicity of Four Chemicals to Selenastrum Capricornutum

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    Bull. Environ. Contam. Toxicol. (1986) 36:254-259 j E n v i r o n m e n t a lC o n t a m i n a t i o n| a n d T o x i c o l o g yE f f e c t o f A c e t o n e o n t h e T o x i c i t y o f F o u r C h e m i c a l s t oSelenastrum capricornutumN. Adam s, ~ K . H , Go u ld ing , 2 and A . J . D ob bs*1pr inces Risborou gh Laboratory, Pr inces Risboro ugh, Bucking ham shire and2School of Natural Sciences, The Hatf ield Polytechnic, PO Box 109,Hat f ie ld, Hert fordshi re, Uni ted K ingdom

    M o s t p r o c e d u r e s f o r th e a s s e s s m e n t o f a l g a l g r o w t hi n h i b i t i o n a l l o w t h e u s e o f a w a t e r m i s c i b l e o r g a n i c s o l v e n ta s a c a r r i e r f o r c h e m i c a l s s p a r i n g l y s o l u b l e i n w a t e r ( IS O ,1 9 8 4; O E CD , 1 9 83 ) . I n g e n e r a l t h e p r o c e d u r e s l i m i t t h ec a r r i e r s o l v e n t c o n c e n t r a t i o n i n t h e f i n a l c u l t u r e t oa p p r o x i m a t e l y 1 0 0 m g 1 - I - 1 0 0 ~ i i - I ). A t t h i s c o n c e n t r a t i o nt h e o r g a n i c s o l v e n t w o u l d n o t b e e x p e c t e d t o h a v e a n ys i g n i f i c a n t e f f e c t o n th e s o l u b i l i t y o f t he t e s t c he m i c a l ; s oi t i s b e s t d e s c r i b e d a s a c a r r i e r s o l v e n t , r a t h e r t h a nc o - s o l v e n t w h i c h i s s o m e t i m e s u s e d a s an a l t e r n a t i v e .H e r z e l a n d M u r t y ( 1 9 84 ) s h o w e d t h a t t h e w a t e r s o l u b i l i t y o fd i e l d r i n a n d n i t r o f e n w a s u n a f f e c t e d b y a c e t o n e u p t o5 0 0 m g 1 - t, b u t t h a t c a p t a n w a s 4 1 p e r c e n t m o r e s o l u b l e .T h e y e x p r e s s t h e v i e w t ha t , o n t h e w h o l e , t h e e f f e c t o ns o l u b i l i t y is i n s i g n i f i c a n t . I n a n y t o x i c i t y te s t, h o w e v e r ,t h e i m p o r t a n t f a c t o r i s w h a t e f f e c t t h e p r e s e n c e o f t he s o l v e n th a s o n t h e t o x i c i t y o f t h e t e s t c o m p o u n d s .A s m a l l n u m b e r o f c a r r i e r s o l v e n t s h a v e b e e n u s e d i n a l g a lg r o w t h i n h i b i t i o n t e st s . H u g h e s an d V i l k a s ( 1 98 3 ) r e c o m m e n dN , N - D i m e t h y l f o r m a m i d e ( DM F) a s a s o l v en t b e c a u s e o f i t sr e s i s t a n c e t o m e t a b o l i s m b y b a c t e r i a ( w h i c h g r o w i n c l o s ea s s o c i a t i o n w i t h a l g a e i n n o n - a x e n i c c u l t u r e s ) a n d L u n d y e t a l( 1 98 4 ) u s e d m e t h a n o l a s a c a r r i e r s o l v e n t w h e n t e s t i n g t h ee f f e c t o f p o l y c h l o r i n a t e d b i p h e n y l s , D D T a n d d i e l d r i n o n m i x e dc u l t u r e s o f m a r i n e d i at o m s . H o w e v e r, t h e m o s t c o m m o n l y u s e ds o l v e n t i n a l g a l t o x i c i t y t e s t i n g i s a c e t o n e . S t r a t t o n a n dC o r k e ( 1 98 1) s t u d i e d t h e e f f e c t s o f a t r a z i n e a n d p e r m e t h r i n o ny P R L. P r e s e n t A d d r e s s : W a t e r R e s e a r c h C e n t r e ,P O B o x 1 6, H e n l e y R oa d , M e d m e n h a m , M a r l o w , B u c k i n g h a m s h i r e ,UK.

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    S c e n e d e s m u s q u a d r i c a u d a a n d C h l o r e l l a p y r e n o i d o s a i n t h ep r e s e n c e o f a r a n g e o f a c e t o n e c o n c e n t r a t i o n s , u p t o I p e r c e n t( 1 0 g i - I) . S h o r t t e r m i n h i b i t i o n o f p h o t o s y n t h e s i s( 1 4 C 0 2 u p t a k e) b y a c e t o n e w a s m e a s u r e d . A l t h o u g ha c e t o n e a l o n e w a s n o t i n h i b i t o r y t o t h e t e s t a l g a e t h e r e w a s ar a n g e o f r e s p o n s e s i n t h e p e s t i c i d e - t r e a t e d c u l t u re s .D i f f e r e n t a c e t o n e l e v e l s d i d n o t s e e m t o a f f e c t p e r m e t h r i nt o x i c i t y b u t a f f e c t e d a t r a z i n e t o x i c i t y i n a n u n p r e d i c t a b l em a n n e r . K l e p p e l a n d M c l a u g h l i n (1 9 8 0) t e s t e d f o r a c e t o n et o x i c i t y a g a i n s t t h e m a r i n e d i a t o m S k e l e t o n e m a c o s t a t u m i n as t u d y o f t he e f f e c t s o f P C B ' s o n d i f f e r e n t c e l l d e n s i t i e s .T h e y f o u n d 0 .1 p e r c e n t ( - 1 0 0 0 m g 1 - I) a c e t o n e h a d n o e f f e c t o nc u l t u r e g r o w t h b u t d i d n o t s t u d y i ts e f f e c t s o n P C B t o x i c i t y .S t r a t t o n ( 19 84 ) u s e d a m e t h o d d e v e l o p e d b y S t r a t t o n e t a l( 1 9 82 ) f o r f u n g i t o d e t e r m i n e t h a t a c e t o n e w i t h a f i n a lc o n c e n t r a t i o n o f 0. 1 p e r c e n t i n c u l t u r e c o u l d b e u s e d a s aC a r r i e r s o l v e n t in a l g a l t o x i c i t y te s t s . H e s t a t e s t h a t t h i sl e v e l d o es n o t g i v e i n h i b i t i o n v a l u e s s i g n i f i c a n t l y d i f f e r e n t(p = 0 . 95 ) f r o m t h e i n h i b i t i o n c a l c u l a t e d f o r a c e t o n e - f r e ec u l t u r e s .A l t h o u g h t h e r e ha v e b e e n s t u d i e s o f t h e e f f e c t s o f c a r r i e rs o l v e n t s t h e m s e l v e s o n t h e g r o w t h o f a l g a e , t h e r e h a s b e e nl i t t l e w o r k o n t he e f f e c t s o f c a r r i e r s o l v e n t o n t he t o x i c i t yt o a l g a e o f c h e m i c a l s b e i n g t e s t e d .T h e s t u d y r e p o r t e d h e r e i n v e s t i g a t e s t h e e f f e c t s o f a c e t o n e a t1 0 0 m g 1 -I ( t h e r e c o m m e n d e d f i n a l c o n c e n t r a t i o n i n th e O E C Dg u i d e l i n e s ) o n t he t o x i c v a l u e s o b t a i n e d f o r c h e m i c a l s o fd i f f e r e n t a q u e o u s s o l u b i l i t i e s . A n i l i n e a n d t e b u t h i u r o n( r e a d i l y s o l u b l e ) , t h e p o o r l y s o l u b l e b u t y l e s t e r o f 2 , 4d i c h l o r o p h e n o x y a c e t i c a c i d ( 2 , 4 - D BE ), a n d a l m o s t i n s o l u b l e1 , 1 , 1 - t r i c h l o r o - 2 , 2 - d i ( c h l o r o - p h e n yl ) e t h a n e ( D DT ) . A l l w e r et e s t e d a g a i n s t S e l e n a s t r u m c a p r i c o r n u t u m u s i n g a s t a n d a r d t e s tm e t h o d. T h e f r e e l y s o l u b l e c o m p o u n d s w e r e c h o s e n t oi n v e s t i g a t e a c e t o n e e f f e c t s o t h e r t h an s o l u b i l i z a t i o n o f t h ec h e m i c a l s b y t h e c a r r i e r s o l v e n t . F o r e x a m p l e P a r a s h e r e t a l( 1 9 7 8) a n d W e i n b e r g e r e t al ( 1 9 8 3 ) s u g g e s t t h a t s o l v e n t si n f l u e n c e t h e u p t a k e o f c h e m i c a l s b y a l g a e , p o s s i b l y b yi n t e r a c t i n g w i t h c e l l m e m b r a n e s .

    M A T E R I A L S A N D M E T H O DST h e m e t h o d u s e d w a s t ha t d e s c r i b e d a s t h e ' PR L' m e t h o dp r e v i o u s l y ( A d a m s a n d D o bb s , 1 9 8 4) , m o d i f i e d t o c o p e w i t h t h ea d d i t i o n o f t e st c h e m i c a l s w i t h a n d w i t h o u t a c e t o n e .S t o c k s o l u t i o n s o f a n i l i n e a n d t e b u t h i u r o n w e r e m a d e u p i ns t e r i l e p a r t i c l e - f r e e d e i o n i s e d w a t e r w h i l s t s t o c k s o l u t i o n s o f2 , 4 - D B E a n d D D T w e r e m a d e u p i n a c e t o n e 2 4 h o u r s b e f o r e t h e i ra d d i t i o n t o t h e c u l t u r e f l a s ks . T h e c o n c e n t r a t i o n s o f t h e

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    s t o c k s o l u t i o n s w e r e s u c h t h a t , w h e n 1 0 ~ l a l i q u o t s w e r e a d d e dt o 10 0 m l c u l t u r e s o f e x p o n e n t i a l l y g r o w i n g S . c a p r i c o r n u t u m ,t h e t es t c h e m i c a l s w e r e p r e s e n t a t t h e r e q u i T e d t r e a t m e n tl e v e l . A s e c o n d s e t o f D D T s o l u t i o n s w a s p r e p a r e d t h a t g a v et h e r e q u i r e d t e s t c o n c e n t r a t i o n s w h e n 2 0 ~ i a l i q u o t s w e r e a d d e dt o 1 0 0 m l c u l t u r e s . I n t h e s e, t h e r e f o r e , t h e f i n a l a c e t o n ec o n c e n t r a t i o n w a s - 2 0 0 m g 1 -~ ; i n s t e a d o f 1 0 0 m g i - ~, t h e O E C Dr e c o m m e n d e d am o u n t. A c e t o n e f r e e D D T a n d 2 , 4 , - D B E a c e t o n e -f r e e f l a s k s w e r e p r e p a r e d b y a d d i n g 1 0 U1 a l i q u o t s o f t h e s t o c ks o l u t i o n s t o a u t o c l a v e d , e m p t y 2 5 0 m l n a r r o w n e c k e d c o n i c a lf l a s k s . T h e f l a s k s w e r e s t o r e d in a n i n c u b a t o r a t 2 2 ~ a n ds h a k e n a t 1 7 5 r p m f o r 2 4 h o u r s w h i l e t h e a c e t o n e e v a p o r a t e d .A l l e x p e r i m e n t s w e r e c a r r i e d o u t i n t r i p l i c a t e , t h e t es tc h e m i c a l s b e i n g a d d e d t o 2 4 h o u r o ld c u l t u r e s c o n t a i n i n ga p p r o x i m a t e l y 1 04 c e l l s m i -~ o f e x p o n e n t i a l l y g r o w i n g S.c a p r i c o r n u t u m . A n i l i n e a nd t e b u t h i u r o n w er e a d d e d i n p a r t i c l ef r e e d e i o n i s e d w at e r , i m m e d i a t e l y f o l l o w e d b y 1 0 ~l a c e t o n e f ort h e s o l v e n t c o n t a i n i n g r e p l i c a t e s . D D T a n d 2 , 4 - D B E w e r e a d d e di n a c e t o n e a n d t h e i r a c e t o n e f r e e r e p l i c a t e s w e r e p r e p a r e d b yt r a n s f e r r i n g t h e cu l t u r es , u s i n g a s e p t i c t e c h n i q u e , t o t h es t e r i l e f l a s k s c o n t a i n l n g t h e c o m p o u n d s p r e p a r e d 2 4 h o u r se a r l i e r . T h i s w a s t e r m e d d a y O . T h e c u l t u r e s w e r e i n c u b a t e da s a b o v e f o r 6 d a y s a n d t h e c e l l c o u n t f o r e a c h C l a s k w a sr e c o r d e d e v e r y 2 4 h o ur s , u s i n g a n E l z o n e 8 0X Y e l e c t r o n i cp a r t i c l e c o u n t e r ( P a r t i c l e D a t a L t d) .T h e c u l t u r e s c o n t a i n i n g 5 m g 1 - I D D T w e r e a n a l y s e d a t t h e e n do f t h e e x p e r i m e n t t Q e s t a b l l s h t h a t t h e r e w a s, i n f a c t, D D Tp r e s e n t . F i r s t l y t h e D D T w a s e x t r a c t e d f r o m t h e c u l t u r e s w i t h1 5 m l a n d 5 m l o f h e x a n e . T h e h e x a n e s a m p l e s w e r e c o m b i n e d ,m a d e u p t o 2 5 m l a n d s t o r e d a t 4 ~ u n t i l r e q u i r e d f o r a n a l y s i s .T h e c u l t u r e s w e r e t h e n l y s e d w i t h a S o n i p r o b e a n d h e x a n e w a sa g a i n u s e d to e x t r a c t a n y r e m a i n i n g D D T, t h o u g h t h e l y s e dc u l t u r e s a n d h e x a n e d i d n o t s e p a r a t e o u t c l e a r l y . A l l t h es a m p l e s w e r e a n a l y s e d b y g a s c h r o m a t o g r a p h y , u s i n g a P y e 1 0 4( P y e U n i c a m Lt d ) w i t h e l e c t r o n c a p t u r e d e t e c t i o n .

    R E S U L T S A N D D I S C U S S I O NU s i n g t h e d a i l y r e p l i c a t e c e l l c o u n t s f o r t e b u t h i u r o n , a n i l i n ea n d 2 , 4 , - D BE , t h e a r e a s u n d e r t h e g r o w t h c u r v e o v e r d i f f e r e n tc u l t u r e p e r i o d s w e r e c a l c u l a t e d . T h e a r e a s fo r e a c h t r e a t m e n tl e v e l w e re c o m p a r e d t o th e c o n t r o l s u s i n g D u n n e t t ' s m e t h o d( Z a r, 1 9 7 4 ) , a s d e s c r i b e d e l s e w h e r e ( A d a m s e t a l , i n p r e s s ) , t og i v e t h e l o w e s t c o n c e n t r a t i o n s t e s t e d t h a t c a u s e d a s i g n i f i c a n te f f e c t ( p = 0 . 9 5 ) ( L C S E ) . L C S E v a l u e s w i t h a n d w i t h o u t a c e t o n ef o r t e b u t h i u r o n a n d 2 , 4 - D B E ( T a b l e I) a r e a l m o s t i d e n t i c a l ,a n d t h e c l o s e s i m i l a r i t y o f g r o w t h c u r v e s f o r t e b u t h i u r o n( F i g u r e s I a n d 2) s u p p o r t t h e v i e w t h a t a c e t o n e h a s h a d n oe f f e c t . T h i s s u g g e s t s t h e u s e of a c e t o n e a s a c a r r i e r s o l v e n tw i t h a f i n a l c o n c e n t r a t i o n i n c u l t u r e o f 1 0 0 U I 1 - I i sa c c e p t a b l e .

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    T a b l e I L o w e s t c o n c e n t r a t i o n o f t e s t c h e m i c a l s ( ~ g m l - ~)c a u s i n g a s i g n i f i c a n t r e d u c t i o n ( p = 0 . 9 5) i n g r o w t h o fS e l e n a s t r u m c a p r i c o r n u t u m . V a l u e s c a l c u l a t e d u s i n g a r e a u n d e rt h e g r o w t h c u r v e ( c e l l c o n c e n t r a t i o n a g a i n s t t i m e)D a y s u s e di nc a l c u l a t i o n

    2 , 4 - D B E T e b u t h i u r o n A n i l i n e

    A c e t o n e N o n e A c e t o n e N o n e A c e t o n e N o n eI to 3 3 3 0 .07 0.0 5 I 5I to 4 3 3 0. 05 0.0 5 I 3I to 5 3 3 0 .05 0.0 5 5 3I to 6 5 3 0.0 5 0.0 5 5 3

    T h e L C S E v a l u e s a r e h i g h e r b y d a y 5 f o r a n i l i n e w i t h a c e t o n ea n d d a y 6 f o r 2 , 4 - D B E w i t h a c e t o n e b e c a u s e c o n t r o l c u l t u r eg r o w t h i s s l o w i n g a s i t r e a c h e s t h e s t a t i o n a r y p h a s e a n d t h et r e a t e d c u l t u r e s ar e c a t c h i n g up . T h e t e b u t h i u r o n t r e a t e dc u l t u r e s i n F i g u r e s I a n d 2 a r e a l s o c a t c h i n g u p w i t h t h ec o n t r o l s , w h i c h a r e r e a c h i n g t h e s t a t i o n a r y p h a s e ; b u t i t i sn o t s u f f i c i e n t to a f f e c t t h e L C S E v a l u e r e c o r d e d . T h e r e s u l t so b t a i n e d f o r a n i l i n e a r e c o m p a r a b l e t o th o s e o b t a i n e d b yC a l a m a r i e t a l ( 1 9 8 0 ) u s i n g S. c a p r i c o r n u t u m .D D T a t t h e c o n c e n t r a t i o n s t e s t e d i n t h i s e x p e r i m e n t ( 5 ~ g m l - ID D T w i t h 2 0 0 ~ l i -~ a c e t o n e ) d i d n o t a f f e c t t h e g r o w t h o f S .c a p r i c o r n u t u m . C o n s i d e r i n g th e w i d e v a r i e t y o f r e s u l t so b t a i n e d w i t h o t h e r g r e e n a l g a e t h e r e s i s t a n c e o fS. c a p r i c o r n u t u m is p e r h a p s ho t s u r p r i s i n g . M a n y r e s e a r c h e r sh a v e f o u n d D D T h a s n o e f f e c t o n d i f f e r e n t s p e c i e s a tc o n c e n t r a t i o n s u p t o 1 0 0 ~ g i -I ( L ai a n d S a x e n a , 1 9 8 2) w h i l s to t h e r s h a v e f o u n d a n ef f e c t o n a lg a l p o p u l a t i o n d e n s i t y a tc o n c e n t r a t i o n s a s l o w a s I ug 1 - I ( G o u l d i n g a n d E l l is , 1 9 8 1 ).T h e G C a n a l y s i s o f 5 ~ g m l - ~ D D T c u l t u r e s i n d i c a t e dc o n c e n t r a t i o n s o f a p p r o x i m a t e l y 4 ~ g m l -~ D D T ( t hu s c o n f i r m i n gt h a t t h e r e w a s D D T p r e s e n t ) .T h e r e s u l t s o f t h i s i n v e s t i g a t i o n s u g g e s t t h at t h e u s e o fa c e t o n e a s a c a r r i e r s o l v e n t w i t h a f i n a l c o n c e n t r a t i o n o f1 0 0 ~i 1 - ~ is a c c e p t a b l e i n a l g a l g r o w t h i n h i b i t i o n t e s t s. T h er e s u l t s o f t h e D D T e x p e r i m e n t s u p p o r t t h e v i e w t h a t t es ts p e c i e s i s a v e r y i m p o r t a n t v a r i a b l e , a n d t h e r e s u l t s o b t a i n e dd e p e n d h e a v i l y o n t h a t c h o s e n . M o r e w o r k i n t o t h e i m p o r t a n c eo f t e s t s p e c i e s i s r e q u i r e d .R E F E R E N C E S

    A d a m s N, D o b b s A J ( 1 9 8 4 ) A c o m p a r i s o n o f r e s u l t s f r o m t w om e t h o d s f o r a s s e s S i n g t h e t o x i c i t y o f a m i n o t r i a z o l e t oS e l e n a s t r u m c a p r i c o r n u t u m . C h e m o s p h e r e 1 3 : 9 6 5 - 9 7 1 .

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    Received December 26, 1984; Accepted March 13, 1985

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