D. 8, Sergeant and j!. Z i t ~ o

Fisheries and Environ~iiental Sciences

?i.:art;;:ent of Fisheries a d Oceaiis B j o l c g i c f i : Stztjoc

Zt, ~ " ~ , n ~ r e ~ v . r , kiii 3 r ' u n s ~ . i ~ k C9G 2Xi)

@ Minister o i Supply and Serv ices Canada 1979

Cat. no. Fs 97-5/8236 ISSR 0701-7626

Sergeartt, D. B., end V, Z7 tko, 1379. The ae?,ermi:;atfofi ,:"?rr:ch"rfon, rjjc?j;r.vi;s f'e,j+'-- s ' , I ~y..i~iori, -C aind phospharr~idon i n mSer, Fish. Mar- Serv. Yeti?, Rep. $36, i-i3 1- 12 p *

-.-, Ine conce?~tsa t icn of ?;richlo:-:on in sam[?les Fb3!i! the irjiJ76 (Dr. P, E s L Syir:ons? dnd 1971 [Mr. ?.W, S a ~ n d e r s ) fcres-l sprd;ilnrj nioritoring p r i g r a m s is re ;~er te ; !~ rhc, coiicentracioii of t r ich!orf i ;n i n rnos",f the 1976 samples excecoed 100 fig/:ill.., in 1977, tr le co.;cen;?"riit { o f i s were considera:>!y lower, w i t h a inaxjmtji?; ~ d l l ~ e of 58 nglni i .

A new net5aci for t h e diiteri~intiiion of trichlorfo.;, i,dsec on s l i y i a t j o f i j r j i l c*:ro; r iabogrdj jhy sslyldted "c icn lo r fan , i s desc r ibed ,

Key words: t r ichlsr+^on, b i c n ' c ; r v o s , "er?l'tr~tl;:~3r,, ;~hnsji&~r;;:rid;in, extrdc"io.r, de:er~jnatjon, Xi\D-2 i n , " - s I iy; iteu trichiorfr;n, 3 r g d n ~ i ? h i ; s p h 0 r s insec-:ic<des

7ne cbJe~"clv@ of t k 1 5 study was t o (:eter,i~ine the l e g e l s cf tn? ~ r ~ a n o p h o s p n a t e ~ n s e c t ~ c r d e t r ~ c h l o r f o n [(2.2,2-tr1ch~cro-l-hydrcxye~hyl)-pnosphonic a c ~ d d ~ n e t h y l e s t e r ] In 1977 f1e16 samples and t o evaluate XAD-2 m a c r o r e t ~ c u l a r resin f o r the ~ s o l a t ~ o n of some o-ganophosphorus ~ n s e c t r c ~ d e s . T r ~ c h l o r f o n leve l s were of ~ n t e r e s t as we wished t o ascer ta in whether t h e post-spray leve l s o f t h ~ s ~ n s e c t ~ c i d e (bsed In New S r u n s ~ i c k agalnst t h e spruce budworn! ~n areas known t o c o n t a i l a l a rge poi 1 rnator popul a t ~ a n ) were higher than 50 ng/mL. T h ~ s concentratvan of t r1ch lor fon rs known t o Be t o x ~ c t o caddisf ly larvae wh~cii evacuate t h e ~ r cases or d ~ e a?; this level P, E, K. Syrnons, pers, crirm. ) , Evacuat'ion of : h e ~ r cases 1s tanfamount t o death as the Insect becomes exposed t o p ~ a a t o r s , In 1975 O r , Spans" exger~rrei i ts -;nd?cateri t h a t the 8 oz/acre app i~caz?on o* t r ~ c h l o r f o n appeared t o have a potentla1 f o r a s ~ g n ~ f ~ c a n t k 7 T i . In 1977 t h e cagea cada1sf:y larvae o f J, a4. Sabnders d ~ e d a t Lake Brook, b u t a t no other s a i ~ p i qng :ricat:gns. i t was therefore suspected thar. Lake Brook sanijiles would show h ~ g h leve l s of trr chlorfan*

I n t h e present sttidy, the sditiples wrre ~ x t r a c t e i l t n ~ n ~ ~ t boil prcviou.; ly dcvcl ojierl r n tills l a l > ~ r a l o r y

i l i r tko and 5erc;ea.t IOii) a*, ~ir2 1 3s b j a iirwiy developed XAD-2 resln sorpt Ion ,nethod. I t was hoped t h a t this metbod would r e q u ~ r e a shor te r zlme as we1 1 a s nrlnjm~ ze the s o l v e ~ t reqliireo per a n a l y s ~ s . Regardless of t h e ex t rac t ion method, a i l samples were s ~ l y l a t e d n r l o r t o gas chromatography with a flame photonetr lc detecLor ( F P D ) . SI 147 a t lon was used t o caaver t t r lch:orfon a more v o l a t i l e , therma2ly s f a b l e molecule. Th7s type of d e n v a t ~ z a t l o n 1s we71 doc1~rnen:ea i n the l i t e r a t u r e (Poole 1971; P;erce 1968) and ei im?nates the t~ne-consbn?ng s tep of converting t r i c k l o r f o r t o d i c h l o r v o ~ (Zitko and Sergeant 1977).

XAD-2 macroreticiil dr res" ext.riicCtien tilfithod~ were a l s o invest igated f o r dichlorvos (Lrichlorfon dehgdrochlorir~at ion and real-rdnqeiiiei~t product. phosphoric acid ?,?-dlch7nroethenyi diriieihyl c.;trr; CDVP) and fenitrotblion fphosjihorothioic. a c i d 0,O-diiriethyl 3-(3-~ricthyl -4-ni trophenyl e s t c r J . 130th t h e s e insi:cticicies were ident i fieti previously i n the 1976 f i e l d samples, The presence of fen i t ro th ion in t h e sanrples i s o f concern as i t coilid Sndicate ca re lessness i n spraying operations, t h a t i s , a czrryover of the insec t ic ide from "Le fen i t ro th ian spray regime to "Le t r i c h i o r i o n s;Jray area. This somwhat negates the whole reason f o r using t r i c h l o r f o n (reduct ion of exposure of pol 1 ina tors t o f e n i t r o t h i o n ) , Feni trothion, a t low i e v e l s , was i d e n t i f i e d in the ear ly spray sanrpies on the basis of gas chroiiiatographic re ten t ion time, but was not found i n 1 a t e r samples, i .e. , second spraying of same area. A t t h e same time XAB-2 methodo?ogy was developed for phuspi-ramidon [phosphoric acid 2-chioro-3-(diethy- I aiai no) -1-methyl -3-0x0-l -propenj/l dimethyl es te r3 in t h e event t h a t analysis of t h i s compound would become necessary an3 t o increase our knowledge of the aop: icabi l i t y cf XAi i -2 sorjit fon t o other organo- phosphate ~ n s e c t i c i d e s .

Macrorericr:lar res ins a re freqileritly used tc ex t racc t r a c e organic compounds fron water and niood [Junk e t d l . 1974; Geibke e t a i . 19781, Alninst any c i zss o f compntinds can be analyzed by varying the sorg t ion cci;diticns ( p i i ) , the elut ion conditions jsalvent 2nd pH), o r !using res ins cf d i f fy ren t sorl?"or? rharac te r i s :~cs ! X i i l l - 1 t o X n D - l i ; ,

1 - Li te ra ture ;i; aliai ] a b l e froin the resin rnan~facturer (Rohm and Haasj on ~ G W to pbricy the res ins , how to pack the resins i n t o chromatographic columns, physical !~roper.ties of +,he resins and so for th (Anon, .974; Anon, 19723; Anon" i 9 7 S b j - Poor i n i t i a l recoveries do not necessar i ly i n d i c a t e that the conipound cannot be extracted by or eluted from an ?AD-col umn* The wrrjng resjn, eluant , pi?, or a combinst?on of a l l three may be ha*i-ing adverse a f f e c t s upon recovery of the comporind (Junk e t a1 .. 1974; Stepan ai;d Smith : Y f 7 ) , A mini-column procedure, requiring only 50-100 mi of sample conpared t o the usual ? L using XAD-4, has been Ceveloped for water analysis {Tateda anti F r i t z 1978). Oerkane e t a l . ( 1 9 7 1 ) used XAD-7 t o recover f e n i t r o - tllion from water and as a preservation technique.

Szalontai (1976) studied the retent ion of twenty-three orjanophospharus insectfcides on a srii ica gel ca7umn using h i g h performance l iqu id chromatography ( H P I C ) . Chre:natographic conditi ons were determined for thc analysis of a cumber of phosphonic acid e s t e r s , phosshoric 2ccid e s t e r s , and thiophospharic acid es te r s . Although t r i c h l o r f a n and dichlorvos were run tinder d i f fe ren t eluant condit ions, examination o f t l i e datd indicates that dichlorvos shni i i t i el i l t e froin the s.i I ica gel col tiinn liefore t r ichlorfnn, tx t rapn la t inq Priiiii S z a i q n t a i k dat .a , grad ic.nt. c ' i iil.ion iiPi C on s i l ic;i cjiii col i11r4n

pwbbsbiy corild bi* irseid i,o clinl i l i i t t * env iran~r~cni.al sari~;~les f a r "Lriciilorfnn and dicirlc;r\ios.

Kri jsrndn 2nd Vdn cif Kamp (1976) iiti 1 ized capi l i ary column yas chromatography to determine a nuinber of organopliosphori;s insect ic 'des . Their data siovi t r i ch ior fcn haiilriij a shorter retent ion time than dichlorvos. Based on the 1 i t e r a t u r e (StZn 1977; Devine 1373; Anderson et a ] . 3966; El-Refdi 1S65), she s t ruc tures of these two insec t ic ides (Appendix A ) and our ljnpubi jshed r e s u l t s , t h i s see:ns qiiestionable. The peak iden t i f i ed by Krijsman and Van de Kamp as t h a t of t r i ch lor fon i s probably due to d imethy? phosphite produced by t h e r n a i decni::yosit?'on o f Lrichlorfori.

a ) Pes t ic ide grade so? ve?is a?d r.eagc?nt grddc chemicals wer? used t4rauc;hoi:t t h i s work;

O: Trichlorfori, cichlorros and phospiiriznfdor; ~ l e r e fron a Pes t jc jde ( i t (Chfm Service, Media, P A ) , Feni t rothion ){as from a laboratory stock of technical grdde product , provided by Forest Protectiofi Limited:

c ) Tri-Si? siiyl~"Ll'ng p a g e n t was piircliased fron Chromatographic Special tSes (Rrfickvili e ; Ontario) ;

6) Ainberl~tr XM-2 resir *,#as o a t a ~ n e d r i d F ~ s h e r Scier:ei'fic frijrn E2st:ndr;. Tile XAD-2 was r~ot c i eariecl t i p prior" to us?* Fines were renoved by siiirrying i n ( i j s & ' - - L~ I ed water and decantafiion. XAO-2 was stc~reii i:! i.icthan01 u n t ~ I t.ased, A s t r o n g najjkti-laiene s;r:el l was rruted to come froni the XAD-rnethsno? :rilxrure, ?hi; iii:piirii;y may have to be ren:eved if other t h d n f36 detect ion were to be iitil i zed to {it-ec'i :de any passible interference w i t h w a % s of i n t e r e s t ;

-2-

e) Anhydrous sodiurn s u l f a t e (F i sher S c i e n t i f i c ] , i ) fi Finnigan Model 9500 gas chron~atograph heated f o r 1 2 h a t 550°C and s tored in open with i c j e c t o r a t 200QC, cn1u:nn i n i t i a l l y at evaporat ing dishes in a desiccator (phosphorus 120°C then pragrairmed a f t e r scan 20 a t pentoxide used as des iccan t ) ; 4"C/min t o 19C°C.

f ) Si l a n ~ z e d glass wool - f 3 r use In XAD-2 res in columns was purchased from Ai l tech Associates Inc. ( A r l ~ n g t o n H e ~ g h t s , I l l ~ q o ~ s ) .

Cot uiiin was 5" 1 j4'"0.D., !J-shaped g l ass packed with 3mV-101 on Ghronlosorb W, H2, RO/lCO mesh.

&PPARATUS 1 1 ) A ' ~ n n ~ g a n ?lode1 1015 9 mass spectrometer. The mass range 50-500 a.v.u. was scaqned

a ) F l l t e r funnel , Buchner type, Porosl ty B wtih P orrce every 5 s . 24/40 connector (4ce Glass Go., Vine1 and, M.J, ) ;

i i t ) l" Finn1 'jan 6100 ddta sys~ein, b ) One l i t r e separatory funnels w ~ t h B 24/4['

connectors (Emerald Glass Co*, Toronto, Ontar io) ; MLTHODS OF ANALYSIS

c ] 125 m i separatory funnels (F i sher S c ~ e n t r f i c ) ; t7repard tl311 ijt s p ~ ~ e f i mtez samp!es

d j Assorted 500 m L , 250 m L , 100-mL round bottom f l a s k s with f 24/40 necks;

e ) One ? i t r e graduated cyl inder;

f j A good supply of ca l ib ra ted (checked) 15-mi graduated cen t r i fuge tubes with stoppers;

g ) R:si n columns - 30 cm x 12 min o.d. glass col unins w ~ t h t e f f o n stopcocks and $ 24/40 female connector (Emerald GI ass Go., Toronto, Ontario];

h) One l i t r e Erlenmyer f l asks ;

i 1 Magnet~c s z i r r l ng bars and magnetic sf i r r e r s ;

j ) Ri nco evaporator;

k ) Assorted Hamilton syricges (SO0 ul, 250 u i , 100 d l ;

1 ) Assorted clainps and r e t o r t stands f o r support of columns, separatory funnel s and drying funnel s ;

n) Water a s p i r a t o r f o r appl icat ion of vacuum t o drylng funnels and a Kinco rotary evaporator;

n ) Vortex - Genie Pixer.

a ) A Perkin iiiiier Model 990 gas ~11r0iiidt,0(1~dljh equipped with a iiielpar flaine-phol.oiili'tric dctect.or (FPi)) operat ing i n ttie ii nrotie, The detecior configurat ion was :iiodiFied dccorciing to the inrthofi of Buryrt t and Green (1974). Injector and d e t e c t o r manifold teciperatures were 200 and 250°C respect ively.

A 6 ' x 114" B.D., coi led glass column packed with 3% OV-101 or 3% O V - 1 on chromosorb W, H P , 80/100 mesh was i n s t a l l e d in the instrument.

flow razes f g r ttie m trogen c a r r i e r gas, hydrogen, a i r and oxygen were 55, 200, 30 and 25 mL/n>? n respect1 ve l j .

Teiiiperature prograinici ilg was u t l 1 i zeii to ; icceierate the elirtion of la te- i i lut iny peaks ( f e n i t r o t h i o n ) . ihe i n ; t i a i teinperatiire :+as 130°C; program r a t e was R0C/nrin s t a r t i n g 1 inin pos t - in jec t ion ; t h e f ina l temperature was IPO0C. This deviates from the temperature conditions es tab i ished in our previous study and i s a r e s u l t of el i m i nation of the f! ame-out problem.

b) The GCjYS/Corputer systen consisted of:

Us~ng a graduated cyl ~ n d e r , an ~ c u r d t e volume of t ap water was measured out and added t o a separatory Funnel. A s y n n g e was used t o t r a n s f e r calculated aniourrls of each i n s e c t ~ c i d e in ethyl ace ta te into the set>aratory funnel . Table 6 glves t h e l eve l s of lnsec t ic ldes in some of the s p ~ k e d samples. The separatory funnel was then stoppered and shaken t o hoiiiogepl~zi? "ce water splke.

XAD extract zan metlrod dnvelopriierit

XAD-2 resin s o r p t ~ o n nieinoris for tne is01 at lon of d ~ c h l o r v c s , t r l c h l o r i o n , fen1 t ro th ion , and phosphaio~don fro!? water were dew1 ooed. Spl ked water samples were then passed through the col t~nn and recovered by eJutlcrn w t h a7 ?rgatl?c solvent. A c l d ~ f i c a t r o ~ of the water sample ~ e s qecessary to estabi ~ s h favorable conditions for adsorp t~on of some 05 these insecticides an the XAD-2 res lp.

Liquid-liquid extractiofi procedure

a ) Carefully piace i l a r g e iizyr~eiic stirrirng bar jnto each 1-i irlenmyer "Izsk;

b j 3s1ng the I-L graduated c j l l ~ d e r , neasure out 1 L (sample volume cerm~t t l r rg j or a l esse r known volume of sample* - r a ~ s i e r the sample t o the Erl enrneyer f lask and pi ace or1 magnet:^ s t1 r r e r ,

c ) S t a r t s t i r r e r and add i0 g anhydrous sodirm s u l f a t e pcr 100 n3. of sample to the i:rlenmeyer F i ask or add s i i f f ic ient soditlo! $111 f a t e i u sattiratti the sample (i~vidrnccci by !.he la.?. r-cinaining c r y s t a l s of s t r d i ~ i m s u l f a t e refiising Lo dissolve) . I t i q cxtr~rriely .important that the s t i r r e r he s t i r r i n g rapidly acd tha t the sodium si i l fa te i s added gradually, Otherwise a large, slow-to- d i sso ive l u i ~ i p will form;

d ) \!ash down the wal'is of the 1-1 qraduated cylinder s u c c e s s ~ v e l y ~ 7 t h threc 25-mi a1 iquots sf ethyl ace ta te ( L A ) ano add ei>ch wash to the t r lennyer f l a s k conta1n:ng the saxple,

c ) Extract the sarriple f o r 30-45 min using the Vortex s t l i r r ing niethod;

f ) Transfer the corirems of +he l - i : r i FniilYer F i 35%

(sample pl i is extraci,incj solvent) tc a 2-? separiitory filnnei ;

(3) aliow phases to Separ2TC! and drairi the aqueous layer back into the ir;e~myap.

h ) Perform two in:jre idi .ntica1 ex"iaci:ons w i t h 30 m i EA, conhinir ig ti;" c~2~-i-;rcls ;

i) Dry t h e EA extr-acx tht-ough 3 1.1'2-in. plug of anhydroiis sodislnl s u l f a t e i n d s ide arm f i l t e r funnel under a s l i g h t vacuum from the water a s p i r a t o r . Collect the f i l t r a t e i n a 500-mi round bottom f l a s k ;

J ) hash t h e NazS34 plug v t l t h a fu r ther 50 mL of EA;

k) Evaporate m e ex t rac t t o 2-3 rr? on a P ~ n c o or eqir~valenl; racuunl evaporator at water bath temperature of 35-4O0C;

1 ) Transfer the concentrate with three % - m i washings t o a 15-mI graduated centr i fuge tube;

m) Reduce e x t r a c t in cen t r i fuge tube jus t tcj dryness i n a 35-4D5C water bath under a gent le stream of n i t rogen ;

n) Add 250 bL 3f T ~ I - S I I reagent t o sawoles and s t a ~ d a r d s a n d react f o r I h a t rooq t e m p ~ r a t ~ r c ;

o j 2eduoe xhe d e r l v a t ~ z e d samoie t o dryness in the water bath under a g e l t i e stream of nlxrogen. l h ~ s szep i s necersary t o reiilove excess der l $ax r z i n g reagent;

p ) Bring t o anpropna te volume (0.5 t o 10 m L ) w ~ t h EA ana irrrx rhoroughly on Jorter-Gente Wxer pr-ior t o withdraw~ng an a l ~ q u o z f o r GLC analysis.

XAD-2 r e s i n met-hod

a ) I n s e r t a qlass woo>J ~g iq a 30 cin x 12 rm O.De r e s l o cnluiln and %hen add a *l;'et~ianol ~ I l r r r y 3f the XA3-2 res ln t o tbe column u q t ~ l a 5- ro 7-cn bed of resin, f r e e of a l r ouhbles, 1s fornied. Top the coiufiirn with another pl t ig of glass wool ;

b j D r a ~ n t h e n~ethansl almost t o the botton of the u p p e r glass wool ?lug and then brash the nexhanol out of tCie resln wl-h 15 pi of o r g a n ~ c - f r e e d ~ s t l l i e d water jo rgan~c- f ree water can be ppc- pared by passing a i s t l i l e d water throi~gh a large XAD-2 column, drscarding the +I r s t 100-20C m-1,

c ) Accurately measure oi.t 1 L o r krown vriliine of sample and add ? t t o d I- i separatory funnel eqii~pped w ~ t h a 3' 24/40 connector;

d j Place t h e 1-i separatory Fi*ifinel containing the sample i n t c the $ 24/40 j o i n t a t the top of the res in coli;rnil and care fu l ly f i l l the colus~n with sample, ieaving the t e f l o c stopcock on the l-i separatory funnel open, s1 owly apen :he stopcock a t She bottom of t h e resin co'iiimn t o obtain a flosci of about 5 milinin in to a 1 - L beaker, placed under t h e coi iliiin t o toll ec t t h e e f i l uent ;

e ) ,411ow t h e e n t i r e sample t o pass through the column and s top t h e flow when i t reaches the Sottom of t h e upper glass wool plug;

f ) Mash Lhe separatory funnel w i t h t w ~ IiS-i;?i a l iquots of orgdnic-free water a?:owing thein t o pass through tile celi-imn and t o the bottom of the glass ~ 0 3 1 plug;

g ) Nex:, wash the fi:nr~el with 15 mi o f EA and zcdd t o t h e co'lumr?.

h ) Place .; 125-mi. senarator ;~ ffr!nr,e! under the col~;mr a n d allow t h e EA t o pass through the cYiunn, Col lect about 5 tA i n the P8nnei, on t o p of the

- water 1a:jer t h d i conies o f f the co?i;n~n prior t o the iii (coi uirlri dedo vui uir~e] Cher! c lose the slopcock;

i Allow the EA ?:n e q ~ 1 1 Fbriite w i t h the resin fo r 20-30 r ~ i n ;

j ) Open stopcock and a1 low reniainder of EA t o flow a t about; one drop per second Into the receiving separatary funnel ;

k ) Add a fu r ther 50-60 i i i i EA to the 2-L separatory firnnel . washinq down the walls in the process. Reconnect i t tc the co:2a1n and open the stopcock j:ist as the Er, in "ihe cnluain reaches the boitonl of t h e top glass tmol plug, This gives no break in e lu t ion and does not per mi^ !irixing of the two EA el uanl f rac t ions ;

1 ) Let tho coliilnn drain ~ o n ~ i i e t e l y a: t h i s point ;

n;] Drain the bottom watcir iayer froin the 125-mi separatory funnel and t r a n s f e r the 5A e lua te to a iOO-mL o r 251;-s1 round bottom f lask with three EA washings of t the f i~nne1 (2 7 i i each] j

n j Reduce the volii~?e of "Lhc e lua te on Rinco evaporator to 2-3 m l , t r a n s f e r to centr i fuge tube wi th washing (3 x 2 .it7 E A ) , evaporate t o dryness, d e r l r a t i z e and ad,just t o vr.1 uiie as i n Procedure A above ;

o ) Run an eztracircn blank u s ~ n c ~ organlo-free r a t e r as a check for ~ n t e r f e r ~ n g conpounds,

Cliroriiatograjjhy of the deri vat i zed sam~1 es from Procedures A and B was carr ied out on the Perkin Elmer gas ci-tronatograph, Qual t i t a t ion was performed against a der ivat i red t r i chfor fon standard. Standards of dichlorvos and fen i t ro th jon were a l so run to peu-mi; ident~fica";on and quant i ta t ion o f these insec t ic ides i r the sirnples.

The sample extraczs, inci udlng XAD-2 extracted f i e l d samples, were pooled a f t e r dnalysis was ccrnpl e ted , and concentrated, An a? .iquot was analyzed by GCMS*

RESULTS AND DISCUSS !ON

During xhe jnaiys i s of t::c 1975 f i e l d samr>ies, d i f f i c u l t y was encountered i n dichlorvss determinations using the staridard FPD de tec tor setup 1 - - , ;? tko and Sergeant 19773, Sol vent flame-out occurred a f t e r every inject iog, This $#as both inconvenient and tiwe consuini?g* The hydregen had t o be turned o f f sad a f t e r sbout 4 min an attempt t o re3 igh"ite f l a ~ i e coiilti be made. Trivariabiy a couple OF t i n e s &:ring s day's rim, the i'1ai.w would not l i g h t on the first: t r y ( i t ) the meantime the diciriorvis peak -ioiild h a v i ~ passed undetected through t h e ecictecter), The eickiorvijs response was a l so obsecved tc f;dc'?rdtn w h ~ ; i the saop vir? ufne of standard WaS re;jila",ddIy injected (deiec to r or co i uinn i nstahi l jty j a R de-f jni te co7 ticin ;rob1 er! seemed to ex i s t as response was &creasing w l l h t ime. Silyi-8 i c jec t?ons restored response to samoles and standards as d i d ths use o f a new coiuci;;. We Feel t h a t t h i s i s a ::he r c s u i i of FA s"cri;ping c+' some ~ ? ' c t k e OV-I01 i i y i ~ l d pbase off the col ci::~, e x p s i n g 3c::J v e s i t e s ~tkicii ',hen adsorb so:?.- 05 ~ h c simple. Priming of the c o i .jnn wjth si l y l a ted- t r . ichlorfoii staridarc! was a1 so

found t o bc d good way of res to r ing useful resoonse In zne present stuay. Tne chaqges of response necessi t d l e d rbnnl rrg s-andards i e r j freqlrerltly xo bracket t h e samples, averaging the peak h e ~ g h t s of s tandards and using the average f o r c a l c u l a t ~ o n of f i nal concent ra t~ons . A fu r ther reason f o r d e s ~ r~ ng t o e l irnlnate t h e flame-out problem arose from the S a ~ l u r e of the ~ g r " I t o r plug ln the detector froiil constant overuse. The e n t ~ r e de tec tor cel l had t o be taken a p a r t , a71 the o - r ~ ~ g s and the fau i ty plug rep1 aced. T h ~ s resu l ted In cons1 derabl e down-tlrne.

Pr ror t o coiirilesclng the work-up of the I977 f el d samples, t h i s f l ame-oet prohl em was r e c t i f led by rnod;f~cat?on of the FPD. The gas st~pply 7 lnes to t h e de tec tor viere re-plumbed in to the confl g u r a t ~ o n einploYed by 3urget t and Green (1974). 4n oxygen 1 ine was added and t h e hydrogen and a7r l rnes were reversed t o proauce an oxygen-hypervent'lated flame ( s u f f ~ c l e n t oxygen i s now present t o combust the ~ n j e c t ~ o n solvent and thus the f l a ~ e femains 71t) . This n o d i f ~ c a t ~ o n , I n addition t o eliminating the f l aae-cut problem, a l s o may have resul ted i n be t te r d e t e c t o r response.

The s i l y l a t ~ o n procecure f o r t r ~ c h l o r f o n reported In our p r e v ~ o u s study )$as a l s o wodl f~ed- T h ~ s change was necessr tated by the p o s s ~ b l e d e s t r u c t ~ o n of t h e 3% O V - 1 and OV-iO! columns 'by I n jec t ion of s taadards fro191 wh~ch the rernalning s ~ l y l at:ng reagent had not been removed. The exact mechanism of co'iuiiin degrada t~on 7s open t o conjecture. S ~ v c e no losses of t r l ch lor fon or s l l y l a t e d t r ~ c h l o r f o n were observed upon evaporation t o dryness, t h ~ s procedure tias ~ncorporated Into the met+od. The evaporative s tep > n o r t o s i lylat1on was t o renlove any v o l a t i l e s ~ l y l a t e d compounds.

F I E L D SAi.iP1-E AgRLYSES

Taale i gives t n e data o b t a ~ n e d for the 1976 field water samples by GS7nY h p r ~ l y ~ i ~ t o d i c h l ~ r v o s

a s t n e i;~erhod of dekr~rir nlng t r i ch lor fon (Litko and Stlrgeant 1377). These saiaples were col lected by Dr. P.E.K, Syrnons. I t can be seen tha t t h e concentra- t i o n s of t r ~ c b l o r f o n reached a i,lax?mum qaliie of 170-210 nijjiri and t n ~ n dcc4 inea r a p ~ d l y over the next 24 h. The Lake Drooh data renresenx a control unsprayed area ard i n d ~ c a t e a v e r j s l ig+t spray d r ~ f t , Table 2 gives the data For the 1977 f ~ e i d samples by t h e s - i y l a i i o n nethoo. The samples were col l e c t e o iiy rdr, J. W e Saunders d u r ~ n g 2 sore intensive pre- and gost-spray conceqtraxion study. E1-am;nat-ion 09 the iake Brook samples shows a zero ba~kgraurid t r - rc i i io r f~r i level fol ioweo by d r o o d post-ssray r i s e t o 23 ngjrni, The conceqt ra t~on then decl inea rjn"cil the second spraying took olace, when a r ~ s e t o 56 n g i m i iias observed, followed by a aecrease t o 1G nglni over t h e next 11-12 d. All o ther lakes and stvearis recelv'ed only a lo~i- level t r ~ c n l o r f o n contamlqatron. Th?s I S due t o t h e f a c t that on7y Anxon~a Lake Out le t , Magaguadawic and iake Brook were ~ i i ti): n t h e spray block ano could be contani?naxed, The other areas s tudled were on tne boiindaries of the spray area or ~ o i i i p l c t ~ l y o i l t s ~ d r i t .

I n only one case f o r iake Brook 1130 h on 4 / 0 5 / 7 1 d i d t h e cnnc~ntration of t r i ch lor fnn r i s e above the level of 50 nglni, tox ic t o caddisf ly l a r v a e JP.E.X, Symons, pers. corn.). I t rained heavi ly on 0 3 / 0 6 / 7 1 and the brook leve l s rose a f t e r t h e rain. Th is sudden jump in t r i ch lor fon concen- t r a t i o n f o r t h e June 4 saai~nfe there fore night be - ? - attribu-d t o Sol i a r ot- so: i residues of t r i ch lor fon being addee to the stream by the prec ip i ta t ion event ,

4 - Table 1. Trichiorfon levels i n 1916 f :e ld samplesa-

Sample Sanpi e Sai?j;l c t i irie Tr ic i~ lor fon

locat ion date ( h ] ng/rni

Green Brom Brook 2/06/76 2/06/76 2/06/75

3 / 0 6 / 7 6 3 / 0 6 / 7 6 3 / 5 6 / 7 6 3 / 0 6 / 3 6 3 / 0 6 / 7 6 3 / 0 6 / 7 0

4/06/71>

iake Brook 2 / 0 5 / 7 0 3/C6176

aSpray~ng was a t 8 9z w r acre. biietween the ttine :n7s saii:pie was a.iaiy"zed anii

t h e t ~ n e xne r e s t of t ? ~ samples were cnalyzed, tbe temperature of thc storage area msp from 4OG t o 15OC fo r an indeterm~nate length of time due to r e f r ~ g e r a t ~ o n fa? l ure. Some hydro1 ys l s of t r ~ c h i o r f o n tl DDVP ana then breakdo~n of UDVP nay have occurred.

CN.D. = not dereciablc.

Table 3 giges a conparcson af l i y u ~ d - l ? q u ~ d and XAD-2 extrdct ion mexhods f o r s o w f i e l d samples. For samples below the dotted 7 ine, the XAD-2 res ln ana lys i s was done a coilpie of inonths a f t e r a l l other sawple analyses. T h e resu l t s indicate tha t a s i g n i f ~ c a n ~ loss of t r :c.hlor%n occurred over t h ~ s add; t ioral perloti of storage, Of tne r e s u l t s above t h e l i n c , s:x palrs o" the resu l t s agree f a ~ r l y well w ~ t h each other ( a " ] ' Tn the other f i v e cases , th ree pairs shobi h~gller resiilts f o r I i r j u l d - 1 i q u l a t ~ a n F3r XBD-2 e x t r a c t ~ o n ~ n r ? two pairs show the XAD-2 method t o q1vc h i ghcr resu l t s . These alscrepailcies ape :n a; l 1.i ke: lkoad re1 ated t o the sarnpl~ng procedure, i t was concl tded tha t the XAD-2 r e s ~ n e x t r a c t ~ o n 1s as gocd as i i q u ? d - l : q u ~ d extraction,

Tdb'i e 4 i s a very br ief cotnpar-ison of ? ic ju id- l i q u i d extract ion of non-acidified and ac id i f ied dupl i ca te f i e l d samples. The low-le*veI sainples showed very l i t t i e di i fercnce between pairs . The higher level samples showed nore variat ion between pa i r s . I t appears that ac id i f ica t ion (5 m i i i HC1 1 i m e d i a t e i y a f t e r sainoling had no observable e f f e c t on t r i ch lor fon recoveries.

i r e e t i n q o f hair . - f - i i l e d qriarl sample b o t t l e s is d poor jireservat i n n t:ipthotl-. The bot t l es invariably break eSii:n thougii there i , an exjiaris!on vol une. Trichiorfon concentrat incd; i n the saniples could be somewhat diihintis due t o pass! bl e evaporat ion of the i n s e c t i c ibe i r o n ? the exposed surfzces.

Dichiorvos and feni"cotliior? were observed i n measurable quant i t i es as i)ieli as t race leve l s in many of the s~rnpIes , t race be-in3 any peak l ess than twice the basel ine noise l e ~ i c i . Diclilari~os q i ia l t i t a t ion under "Le s i i y l a t i o n method cannot hc rcgarcied as r e l i a b l e i s losses X I J S ~ occur whiner; the sam3le i s

Table 2. ( c o n t ' d )

Sarnp! e Sainpl e Sampl e time Trichlorfon

loca t ion date (h) ng/mL

Wawei g

Clear Lake 31/05/77 1330 0.5

aAppl i ca t ions were 8 c z per acre. ~ N . D . = not detectable .

Note: 1) F i r s t spraying began on Lake Brook and A~thony Brook on the evening of 29/05/77 and was completed 30/05/77.

2 ) Second spraying took place on 01/06/77. 3) Bocabec River and Waweig River were outs ide of he1 icopter spray

blocks. Clear Lake and Magaguadavic R ~ v e r were downstream from several spray blocks.

Table 3. Comparison of 1 iquid-1 iquid extract i o n dnd XAII-2 resin e x t r a ~ t i o n .

Trichlorfon, ng/mL Sample Sample 1 iquid-liquid XAD-2

Location date time extract ion extract ion

Lake Brook a , I,

I I

Magaguadavic River Sparks Lake Anthony Brook Lake Brook Magaguadavic River Clear Lake ---------------------

15.1 15.2 36.0 39.5 38.0 3.1 N.D. 0.1 0. 1 3.2 0.5

---------

Lake Brook 10/6/77 1930 11.6 0.4 I, I , 30/5/77 1130 0.1 N.0.

Table 4. Effect of HCl addition as a preservation method.

Trichlorfon, ng/nl Sample Sample unacidified acid1f2ed

Location date time sample sampie

Lake Brook 1/05/77 1130 23.07 13.90 I 1/05/77 1935 14.95 18.74

~awrence N i 1 l 17/06/77 0930 0.2 0, 2 44awei g 16/06/77 1205 0.2 13.3

evaporated t o dryness before and a f r e r 51 l y l a t ~ n n , The concentrat ions of fen i t ro tb ion were measurable ?n 10 samples and ranged from 0.03 t o I). 3 ng/ini. F ~ g u r e l a i s a t y p ~ c a l chroinatogram of a three insect3cide s tandard and Fig* Ib, run under den tical c o n d ~ t l o n s , i s a laboratory sample containing a l l th ree insec t ic ides .

Fig. l a ) 6 0 p!. inji,' t i o n q f t l l r e c p r i ~ l i .<in s t a i ~ d a r d under t r rnpe ra t~ i r e progrannnt4 c o n d - t i o n s , k t t r n u a t l o n 512, Standard contained 2 . 0 n g l b i d l c h l o r v o s , 60 ng/pL s i l y l a t e d t r r c h l o r f o n and 4 .0 ng/uL f en1 r r o t k ron

b ) 8 VL EA fraction of ' A P ( T a b l e 3) d r i u t e d 500 gL t o 5 mL from a 10 I& f l n a i volume a x t r a c t . At tendat ron 512 , tempera ture p r o g r a m e d .

c ) 6.0 ~ A L TMS-rr~chlorfan s tandard ( 2 . 0 n g / u b ) . At tenuar lon 256, t e s p e r a t u r e p r o g r a m e d .

d l 8 UL o f 3,05 ng/vI, d l c h l o r v o s and 0 .327 n?/pL f r n r t r o t h ~ o n $:andaid, AtLentzarion 2 56 , t.e?cperat,ire pr?grdm~ed.

e l 8.0 GL o f a Irquld-lrquld e x t r a c t e d f i e l d s a m p l e con ta lp lng d ~ c i t i o r v o s , T M S - t r ~ i h i o r f o n and t r a c e f e n l t r o t n l o n . 4 t c r n u a t r o n 256, temGerature programed.

Pr io r t o ac t~ ia l sample analyses, the l ~ n e a r ~ t y of the response versus concentration curve of the s- t lylzcea t r ~ c r ~ i o r f o r was 7 ~ v e s t i g a r e d . As d e ~ i c t e d by Table 5, d ~ f f e r e n t conce?trat ions were rnjected over <our at tenuat ion ranges and t h e peak heights calcu;azed back t o a t t e n b a t ~ o n 256. Flgure 2 1s a lot of the data froln Table 4 ( t h e average vaia~e f o r t h e 80 ng In jec t lo? was p lo t ted) . Alrhough the plot 1 s a curve, tne -eg13n up t o 80 ng rs p rac t lca i ly l i r e a r . Reyonc t h a t , ?he po~nts are q u e s t ~ o l a b l e and t h e degree o f cirvlnrj 1s uncertain, Dur;ng sample analyses, aztenuatron 756 rids used and a s i Yylated t r ; ch lor ron sranoard of 2 ng/,i was ewoloyed. kie tklerefnre opesz-ced i n the regson of the C L J ~ V F 3elol.i 20 ng*

Table 6 i s a record of the resu l t s of vdrious XfiD-2 recovery tes ts f a r the four insccticicfi?s. The soivents used t o e l u t e the resin column are indicated f o r each t r i a l . Ethyl acetate was found t o give b e t t e r wcoveries of "crichlorfnn, dichlorvas and fen i t ro th ion ( in the sane sample) than ethyl e ther . i t was therefore useti t o e lu te the f i e l d sample XAD-2 co1 uinns as we1 1 as most of the spi ked water sainpies.

MASS SPECTliA ANij 2tCDNSP~llCTEC GAS GHROIJATOGRAY OF COIYiBiniEC SILVLATED TRlCkiGRPOII SAMPLES

For the confir~iiatian of s i l y i a t e d t r i c h l o r f o n , some samples from both the extract ion and the XAD procedure were combined, Tkc combined ex t rac t s w r e concentrated t o a small volulae and analyzed by GCMS ( F i g . 31, A l a r g e number of peaks appear in the reconstructed gas cliroinatogram and are represen ta t ive of the insec t ic ides and cn-extractants fro:n the f i e l d samples and of the procedurzi b l a n k (no clean-up adas einployed pr io r Lo FPD dnzlys i s Sue tti the speci f i c i t y of the de tec tor ) .

The peak c?ddichlorvos was present in scan No. 70, and tha t of s i ly la ted- t r ' ch lor fon i n scan No. 172. Since dich'lorvos i s not formed d~i r ing the s i i y l a t i o n , i t mlist have been present in " t h e or iginal sainples.

The level of t r i ch ic r fon i n the combined sample was qu i te low and, cnnseqvcnt7y, the procedural blank became very prozninent and most o f t the major peaks o f the recoristructed gas chromahogram {Fig, 3j a r e minor impuri t ies froin the XAD res in , Junk e t a i . (1974) reported tha t the major const j tuents o f XAU-2 and -4 blanks were naphthalene, ethyl benzene and benzoic acSd, They authors a l so indicated t h a t they observed other minor contdminants (no: ident i Fied j and s ieculated that :heir a r i g i n would be impurities i n t h e s t a r t i n g mater ials Far the res jns .

Table 5. Data f o r s i l y i ated t r i ch lor fon i inear i ty check.

Concentration Cal cul aied uL standard standard inject ion Ng Actual peak hei ght

injected ng/uL injected at tenuat ian on x 256

Tab1 e 5. Recoveries of or,()driol~fiosi>hiite insc?cticides froi!i Mi)-? :ilacrc~rct iciii dr

resin.

Spike l eve? s , ng/nlL % recoveries P: u t i ng Sample dichlorilos t r i ch lor fon f e n i t . dichlorvos t r i ch lor fon Fenit.. solvent

A 20 B I!

G 0 E /I

F G $ 8

W *l

1 Dist.

K /I

L M N Q + tic1 10 R " " 20 T " '0 ii " " ir " .' W " 5 X " A 1 " 10 B i " " S Phosphami don

101-6 E4 80-5 EA? 85-1 E A ? 29.7 ii 19,45 iC 59,s EA

E E = ethyi e ther E A = ethyl acetate

MeOii = inethanol AC = a c e t o n i t r i l e

aThese f i r s t four t r i a l s a t recovery of the three r n s e c t i c ~ d e s are the sum of t h e concentrations recovered b:, the secjuen3al e i a t ~ o n s of the column with the follovr5ng volume of each solvent:

LEXlYL 1 ,DS OVLOX FIELD SWPLE 1977 1-7 1 dr 14 14-12

Fig. 3. RGC of combined 'ITIS-trichlorfon extracts of f i e l d samples.

The t e n t d t l v e ~ d e n t i f ~ c a t i o n of our p roc~dura l blank peaks and rher- mass spectra a re g i v w helow f o r fu ture reference:

Peak No. 14 has qot been l d e n t r f ~ e d . I t appears t o be e s ~ i y l ated jrn/e = 73) nltrogcn corlipouna F1g. 4 ) .

"eak No. 26 I S ethyl s tyrene (Fig. 51, with a no iecu la r ion a; m/e = 132 and the (M-15) ion as t + e base peak of the mass spectrum.

Peak KO. 47 has not been iden t i f i ed (F ig , 6 ) .

P l g . 4. Mass spectrum of unidentified nitrogen compoutrd.

-. r i g . 5. Mass sp4:cirusii o f e i h y l s i y r r n e .

Peak So. 170 d e f i n i t e l y contalns a m ~ x t u r e of coa~lpounds, A phenyi a1 kane and a phthai a t e may be +resent . The presence of $hthalates I n the samples 1s orobably a resu ; t of the thaw~ng process. The boz t les had been ldbel leu w i t h waskinq tape and rnarKer aen. dhen the b o t t l e s f roze, the nrajorlty of them cracked badly. The samples m - e thawed by p i a c ~ ~ g t h e samcle b o t t l e in a 2-1 beater and di1ow:ng theiii t o lnel:. The t h a w ~ r g water then came i n contact w ~ t h t h e tape and p o s s ~ b l y became contamrncited by giue compounds., F o r t u ~ a t e l y , these compounds did aot j e o p a r d ~ z e our 2naiyses by FPD. DSOY,~ .DS CIVLOX F l t X S R C ~ P ~ ~ 1971 r i

r 47 47-a4

103 I C L > 7 >eat i \ ~ s . 193 and 203 have very s ~ m ~ l a r mass s p e c t r a and a re probably isomers of 1-ethylphenyi- 2-pnenylethane (F ig . 8) ~ t h :he molecular ion at m/e = 210, and :he [M-151 Ion as the base peak.

Pe3k 10s. 241 and ?:I have very slinliar nass s p e c t r a and a r e probablv lsoniers of I , ? b15 (elhylphenyl] ~"Lharle ( F I g , 9, t-i-itn t o r inolcc~ilar lor! a t m/e = 233, and the [%-15] Ion az the bare peak.

Peak No. 264 appears t o be a phenylalkane, Frjgmenrlng somewhat d l f f c r e n t l y from compounas rn peaks 40- 193 and 261 (Fig, 10) . The t y p ~ c a l p h e y l alkane s c r l e s of ro/e = 91, 105, and 119 1s prom' neqt

Peak ?4os, 284 and 3613 are dibutyl phthcalate and a para"f i n , respect i uely Pig. 6. Mass spectrum of ~ g n i d e n t i f i e d compound,

scan i i 7 .

F i g . 7. Mass spec t r t tm o f r t i i v l b ~ p h e n y I , scan iiiil.

F i g . 8 . Mass spectralm of isomers of I - e t h ~ l i > h : ? n y l - 2-pheny i e t h a n e .

i : i ~ , ii : . Mass sptxcirc?m of a phi.njila;"nnii i.:i>lnpoiii~d

140 attem;~t was raade i.0 iderl"ify t h e r c ; ~ ~ i i n i i ~ g ii:i nor peaks.

COIZCLLIS IONS

S j Compared to the pre~iinus inethod o f converting t r i ch lor fon to DDV? pr ior t o extract ion and deter- mination, t h e present d i rec t extract ion fo? 1 owed hy s i l y l a t i o n a1 lows a f a s t e r sample work-up. Analysis ~ 5 m e fo- each GC i n j ~ l i o n is longer as tile s i i y l a i e d - t r i c h l o r f o n derivat i ve tzkes longer to e l u t e than dichlorvos.

2 ) Xi iD-2 look.. to be iu-crnising as ar? a; t e r n z t i ve t o l i q u i d - l i q u i d extract ion i n t h e a n a l y s i s of organopnosphorus insect icides. The pH corid"tions f a r adsorption on the resin and for s o h e n t required for e lu t ion may vary depending on the compounii(s) t o be isolated. As t o vihether one can ex t rac t a sample at one pii, readjust to .; secorid pi: and s e i e c t i v c l y remove another compound was not s t u d i e d , but may provide rl possibi e m ~ l t i residr ie neth hod,

3 ) setter storage of f i e l d samples i? the fu ture shoilid be provided-.

4) Use of the XAD-? r e s i n method i n the f j e l d and transpose of only co'lilmn organic e l i i e r ~ i s hack t o t h e laboratory f o r analysis could 3s of Senef-iL,

5 ) i ake Brook safiples, as i n i z i a l l y expected, did contain t h e h i gkest levels of t r i c h l s r f o n found a t any of the 1377 sa~vp; i n g locat ions,

We thdr;k Mrs- Bi'i-irtda iscCu1 lorigh and Mr-s. deanine Hurley for typiinr; the mantiscript, Nr. Bii l t4cKullon for preparing the S9gilrei , and Drs. K, Haya and S. Ray for t h e i r torments, and Ms* 2. Garnett f o r ed i t ing the manuscript.

Anderson, R. J., 6. 8, Anderson, a d T. J * ?Iscn. 1966. A gas-] i q u ~ d chrornatograofiic method f o r t h e determlnat>on of t r i cb lor fon i n plant and animal Tissues. J. Agric. Food Chem. 14: 508-512-

Anon. ?912a. Suan~ary bu l le t in Amber1 ~ t e polyinerlc adsorbents. Rohm and Haas Gompa~y, P h i l a d e l p h ~ a , Pennsylvania, p. 1-9.

1972b- Anberl ~ t e XAD-2 t e c h n ~ c a t bull e t ~ n . 2ohm ana iiaas Company, Phi I adelphia, Pennsylvan~a, p. 1-10,

1974. h b e r i 3te Ion exchange resl ns laboratory guide, Rohiil and lidas Company, Phi ladelphia, Pennsylvania, p. 1-39.

BerKane, K., 6. E. C a i s s ~ e , and V. N. Mallet. 1977- The use of h b e r l I r e XAD-2 resin f o r the ouan"ctat3 ve recovery of f e n r t r o i h ~ o n from water - a preservation techn~que . J. Chrosiatogr. 139: 386-390.

9urgetl;, C. A,, and i., E. Green. 1974. improved f lanie photometrrc netpction WI thout sol vent f l a~neout. J* Chroalaiogr. Sci. 12: 356-359.

Devrne, 2. 1973, Dcteril~inat Ian of t r lchlorfon [D,O-diatethyl (2,2,?-trrciiioro-9-hytJroxyetk,yl) ~hosphona tc ] ~n f c r e s t envsroniiiental samp:es. J. Pyrr t.. Food Cheii~. 21. 1095-1098..

El-re fa^, A. H, 1955, Separa t~on and rmcro c u a n t ~ t a t ~ v e deterrn~nat ion of d7pterex and DDVP by gas-1 tqicid chromatorgaphy, J. Ass, Off. Anal, Chem. 48(2) : 374-379.

Gel bke, M, P . , T, H, Grei 1 , and 6. Schmidt , 1978. :sol a t ion of drugs From blood by column chromatography on Amber1 i t e XAD-2. Arch.. Toxic01 . 39: 214-217.

J u n k , 6. A , , J. J, Richard, M. D. Grieser , D. Witiak, J , i. W i i i a k , t4. D. Arguciia, R. Vick, !I. J , Svec, J. S. f r i t z , and G. V. Cdidcr. 1974. Use of :nacroreiiciilar res ins i n t he ana lys i s of water for t race organic contaminants. J, C'nroinatoogr. 99: 745-762.

Krijsman, W,, and 6, 6. Van de Kan~p, 1976, Analysis o f organophosphorxs pest ic ides by cap i l l a ry gas chromatography with flame photometric detection. J , Ckromatogr. 117: 201-205.

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APPENDIX A

St ruc tures of d i ch lo rvos and t r i c h i ~ r f o n

Uicklorvos

( C ~ H J O ~ C I 2P) M.W. 220 2,2 - d;ch loroc tke~yl d~iirethyl phosphate

i r l c h l o r f o n