United St ates Pr e v ention, P

esticides EP A -738-F-94-024 Envir onmental Pr

otection And T o xic Subst

ances September 1994 Agenc y (7508W) 

# R.E.D. F ACTS

Sodium and Zinc Salts of 2-Mercapto- benzothiazole
Pesticide Reregistration All pesticides sold or distributed in the United St ates must be r egister ed b y EP A, based on scientific studies sho win g that the y can be used without posin

g unr easonable risk

s t o people or the envir

onment. Because o

f adv ances in scientific kno

wled g e , the la w r equir es that pesticides which w er e fir st r egister ed y ear s a g o be r e r egister ed t o ensur e that the y meet t oda y's mor e strin g ent st andar ds

. In e v aluatin g pesticides f

or r er egistr ation, EP A obt ains and r

e vie w s a complete set o

f studies fr

om pesticide pr

oducer s , describin

g the human health and envir

onment al effect s o f each pesticide

. The A g enc y imposes an y r egulat ory contr ols that ar

e needed t

o effectiv ely mana g e each pesticide's risk

s . EP A then r er egister s pesticides that can be used without posin g unr easonable risk

s t o human health or the envir onment. When a pesticide is eli gible f or r er egistr ation, EP A announces this and e xplains wh

y in a R er egistr ation Eli gibility Decision (RED) document. This f act sheet summariz

es the inf ormation in the RED document f or r er egistr ation case 2380, the sodium and zinc salt s o f 2-mer capt obenz othiaz ole

. 

### Use Profile This case includes tw o activ e in gr edient s , the sodium and zinc salt s o f 2-mer capt obenz othiaz ole , which ar

e used as fun

gicides , micr obiocides and bacteriost at s . These salt

s ar e used as pr

eserv ativ es f or adhesiv

es , late x and oil paint s , paper pr

oduct s , met al w orkin g cuttin g fluids and te

xtile fiber

s
. Sodium 2-mer

capt obenz othiaz ole is used in the f

orm o f a soluble concentr ate or liquid t

o contr ol mold, milde

w , bacteria and fun

gi which cause aqueous industrial pr oduct s t o degr ade . The met

al w orkin g cuttin g fluid use o

f the sodium salt o

f 2-mer capt obenz othiaz ole is the only use pattern wher

e effluent cont

ainin g the chemical is dischar g ed int o aquatic envir onment s , potentially e

xposin g non-t ar g et aquatic or

ganisms , includin g endan g er ed species

. This use pattern e

x ceeds the acute Le

v el o f Concern (LOC) f or endan g er ed aquatic or

ganisms . The A g enc y , ther ef or e , has determined that effluent cont ainin g sodium 2-mer

capt obenz othiaz ole should2 not be dischar

g ed int o str eams and other w

aterw a y s wher e endan g er ed aquatic or

ganisms ar

e kno wn t o r eside . When the A g

enc y completes it

s Endan g er ed Species Pr

ogr am, additional pr

ecautionary labelin

g ma y be r equir ed t o miti gate the risk t

o endan g er ed species

. Zinc 2-mer

capt obenz othiaz ole is used in the f

orm o f a soluble concentr ate or liquid and w

ett able po w der t o contr ol mold, milde

w , bacteria and fun gi which degr

ade aqueous industrial pr oduct s , f abrics , and y arns; and slime-f

ormin g bacteria and fun

gi in industrial w

ater s y stems

. Ther e ar e no r egister ed f ood uses f

or either the sodium or zinc salt s o f 2-mer capt obenz othiaz ole

. 

### Regulatory History Sodium 2-mer capt obenz othiaz ole w as fir st r egister ed as a pesticide in the United St

ates in 1949 in an industrial pr eserv ativ e pr oduct. Curr

ently , only one pr

oduct is r egister ed, f or use in w

ood and paper/paperboar d tr eatment and as a pr

eserv ativ e in met al w orkin g cuttin g fluids , emulsions

, te xtiles and pastes

. Zinc 2-mer

capt obenz othiaz ole w as fir st r egister ed as a pesticide in the United St ates in 1955 in an industrial pr eserv ativ e pr oduct. Curr

ently , tw o pr oduct s ar e r egister ed f or use as pr

eserv ativ es in adhesiv

es , te xtiles , paint s , coatin g s and paper pr

oduct s
. The par ent compound, acid o

f 2-mer capt obenz othiaz ole , w as r egister ed as a pesticide activ

e in gr edient in 1956. Ho

w e v er , all pr oduct s cont ainin g that chemical ha

v e since been canceled.


### Human Health Assessment T

oxicity Zinc 2-mer

capt obenz othiaz ole has been placed in T

o xicity Categ

ory III, which indicates moder ate t o lo w acute t o xicity , f or acute skin and e

y e effect s . Ho w e v er , the sodium salt is placed in T o xicity Categ

ory I, indicatin g the hi ghest degr

ee o f acute t o xicity , f or skin and e

y e effect s because it is e

xtr emely acidic (with a Ph o f 1 1.5). The acid o

f 2-mer capt obenz othiaz ole is classified as a non-quantifiable "Gr oup C" car

cinog en; a possible human car cinog en. A linear

, multi-st a g e model f or cancer risk assessment w as not appr

opriate because the use o f this pesticide is not lik

ely t o r esult in r epeated human e

xposur e o v er a si gnificant portion o f the human life span. Mar gins o f Exposur

e (MOEs) w

er e calculated t

o quantify the risk t

o applicat or s/mix er s/loader s . The MOEs f

or the pr eserv ativ e and met al w orkin g cuttin g fluid uses o

f zinc and sodium 2-mer capt obenz othiaz ole e x ceed 1 00 (the mar

gin consider

ed accept able) b y se v er al or der s o f ma gnitude . Ther ef or e , additional e

xposur e studies w

er e not w arr anted, and the A g

enc y r equir ed dat a on acute

, de v elopment al and subchr onic t o xicity and mut

a g enicity only

. Occupational and Residential Exposure The methods o

f application f

or pr oduct s cont ainin g sodium or zinc 2-mer capt obenz othiaz ole that include open pourin g o f liquid concentr

ate ,3 and open pourin

g o f po w der int o adhesiv es and paint

s , pr esent the potential f or dermal and inhalation e xposur e t o applicat or s . Dermal e

xposur e is the primary r oute o f e xposur e o f sodium and zinc 2-mer capt obenz othiaz ole

. EP A w as concerned about the risk s o f dermal and inhalation e xposur e associated with the application o f sodium 2-mer

capt obenz othiaz ole f or the met al w orkin g cuttin g fluid use

, and r equir ed a dermal e

xposur e study t o assess the risk

s t o w ork er s . The study w

as designed t

o r eflect typical w

ork pr actice inv olvin g the biocide in industrial use . The final assessment o f the study indicated that some absorption int o the skin occurr

ed. Ho w e v er , since ther e ar e no special t

o xicological concerns about the sodium or zinc salt s , EP A is not imposin

g P er sonal Pr otectiv e Equipment (PPE) r

equir ement s on use o f the pr oduct s
. P ost-application e

xposur e fr om tr eated paint, adhesiv

es , te xtiles and other tr eated industrial pr

oduct s ar e not consider

ed significant because o

f the lo w concentr

ation/dilution f

act or t o the tr eated pr oduct s . Ther e ar e no r esidential uses o

f sodium or zinc 2-mer

capt obenz othiaz ole . Ther ef or e , the potential f

or an y si gnificant r

esidential e

xposur e is v ery lo w . Human Risk Assessment The sodium and zinc salt s ar e not r egister ed f or an y f ood or feed r elated uses

, so no diet

ary risk s ar e posed. The potential f

or r esidential e xposur e and risk is v

ery lo w . W ork er s (mix er s , loader s and applicat

or s) ma y be e xposed t o these pesticides , especially durin

g open pourin

g o f liquid and po

w der f ormulations

. Ho w e v er , the A g enc y has determined that use o f these pesticides is not lik

ely t o r esult in r epeated human e

xposur e o v er a significant portion o

f the human life span. The est ablishment o

f activ e in gr edient based PPE r

equir ement s is not w arr anted at this time

. The PPE f or pesticide handler

s will be based on the acute t o xicity o f the end-use pr oduct. 

### Environmental Assessment Environmental Fate A h y dr oly sis study has been r

equir ed on the technical gr

ade o f sodium 2-mer capt obenz othiaz ole f or industrial use pr

oduct s wher e effluent is potentially dischar

g ed int o aquatic envir

onment s . While the A g

enc y has r equir ed the study t

o be based on the industrial use pattern, major envir onment al e xposur e t o the sodium salt is not e xpected. The A g

enc y will use the r esult s o f the study t

o confirm this assessment and the degr adation r ate o f the activ

e in gr edient and pr

oduct s f ormed durin

g h y dr oly sis

. Ecological Effects Risk Assessment 2-Mer capt obenz othiaz ole is almost nont

o xic t o bir ds on an acute or

al basis and is only sli ghtly t o xic t o bir ds on a diet

ary basis . Ho w e v er , it is hi ghly t o xic t o fr eshw ater fish and moder

ately t o xic t o aquatic inv

ertebr ates

. The use patterns o

f the sodium and zinc salt s , e x cept f or sodium4 2-mer capt obenz othiaz ole's use in met

al w orkin g cuttin g fluids , indicate that the y will not pose risk

s t o a vian and aquatic species

. Unlik e a gricultur al situations

, wher e aquatic or

ganisms can be e

xposed t o pesticides via runo

ff or spr a y drift, nont

ar g et aquatic or

ganisms w

ould be e xposed t o industrial micr

obiocides thr

ough a point sour

ce dischar

g e . The met al w orkin g cuttin g fluids use o

f the sodium salt is the only use pattern which ma y r esult in an effluent dischar g e int o aquatic envir

onment s . It ther ef or e poses the potential f

or e xposur e t o nont ar g et aquatic or

ganisms , includin g endan g er ed species

. EP A's aquatic risk assessment indicates that minimal risk is posed t o fr eshw ater aquatic or

ganisms in r

eceivin g str eams at mean flo

w r ates

. Ho w e v er , under hi gh e

xposur e conditions

, a hi gh acute and chr

onic risk is posed t o fr eshw ater aquatic or

ganisms . The hi gh e

xposur e scenario also e x ceeds the LOC f

or endan g er ed fr eshw ater fish and inv

ertebr ate species

. Ther ef or e , effluent cont

ainin g sodium 2-mer

capt obenz othiaz ole should not be dischar

g ed int o str eams and other w

aterw a y s wher e endan g er ed aquatic or ganisms ar

e kno wn t o r eside

. 

### Additional Data Required A h

y dr oly sis study has been r

equir ed t o confirm the envir

onment al assessment b

y determinin

g the degr

adation r ate o f sodium 2-mer

captobenz othiaz ole and pr

oduct s f ormed durin

g h y dr oly sis . EP A also is r equirin g pr oduct-specific dat

a includin g pr oduct chemistry and acute t o xicity studies

, r e vised Confidential St

atement s o f F ormula (CSFs), and r e vised pr oduct labelin

g f or r er egistr ation o f pr oduct s cont ainin g sodium or zinc salt s o f 2-mer capt obenz othiaz ole

. 

### Product Labeling Changes Required The labels o f all r egister ed pesticide pr

oduct s cont ainin g sodium and zinc salt s o f 2-mer capt obenz othiaz ole must comply with EP A's curr ent pesticide labelin

g r equir ement s . The f ollo win g st atement also must appear on the labels o

f sodium 2-mer

capt obenz othiaz ole end use pr

oduct s with the met al w orkin g cuttin g fluid use: **E ffluent Dischar**  **ge L abeling St**  **atement** - "Do not dischar

g e effluent cont ainin g this pr oduct int o lak es , str eams , ponds , estuaries

, oceans or other w ater s unless in accor

dance with the r

equir ement s o f a National P ollut ant Dischar

g e Elimination Sy

stem (NPDES) permit and the permittin g authority has been notified in writin g prior t o dischar g e
. Do not dischar

g e effluent cont

ainin g this pr oduct t o se w er s y stems without pr

e viously notifyin

g the local se

w a g e tr eatment plant authority . F or guidance cont

act y our St ate W ater Boar d or R egional Office o f the EP A." When the A g

enc y completes the Endan

g er ed Species Pr

ogr am, additional pr

ecautionary labelin

g ma y be r equir ed t o miti gate the risk t

o endan g er ed species

.5



### Regulatory Conclusion The use o f r egister ed pr oduct s cont ainin g sodium or zinc salt

s o f 2-mer capt obenz othiaz ole will not pose unr

easonable risk

s or adv er se effect s t o humans or the envir

onment, pr

o vided that these pr

oduct s ar e used in accor dance with the r

estrictions on pr

oduct labelin

g. Ther ef or e , all uses o

f these pr oduct s ar e eli gible f

or r er egistr ation. Sodium or zinc salt s o f 2-mer capt obenz othiaz ole pr oduct s will be r

er egister ed once the confirmat

ory g eneric dat a, the r equir ed pr oduct-specific dat

a, Confidential St

atement s o f F ormula and r

e vised labelin

g ar e r eceiv ed and accepted b

y EP A. 

### For More Information EP A is r equestin g public comment

s on the R

er egistr ation Eli gibility Decision (RED) document f or sodium and zinc salt

s o f 2-mer capt obenz othiaz ole durin g a 60-da y time period, as announced in a Notice o f A v ailability published in the F eder al R egister . T o obt ain a cop y o f the RED document or t o submit written comment s , please cont

act the P esticide Dock

et, Public R

esponse and Pr

ogr am R esour ces Br anch, F ield Oper ations Division (7506C), Office o f P esticide Pr

ogr ams (OPP), US EP A, W ashin gt on, DC 20460, telephone 7 03-305-5805. F ollo win g the comment period, the sodium and zinc salt s o f 2-mer capt obenz othiaz ole RED document will be a v ailable fr om the National T echnical Inf

ormation Service (NTIS), 5285 P ort R o y al R oad, Sprin

gfield, V A 22 16 1, telephone 7

03-487-4650. F or mor e inf ormation about EP

A's pesticide r

er egistr ation pr ogr am, the sodium and zinc salt

s o f 2-mer capt obenz othiaz ole RED, or r

er egistr ation o f individual pr

oduct s cont ainin g sodium and zinc salt

s o f 2-mer capt obenz othiaz ole , please cont

act the Special R

e vie w and R er egistr ation Division (7508W), OPP , US EP A, W ashin gt on, DC 20460, telephone 7

03-308-8000. F or inf ormation about the health effect s o f pesticides

, or f or assist ance in r ecognizin g and mana

gin g pesticide poisonin

g s ympt oms , please cont

act the National P

esticides T

elecommunications Netw ork (NPTN). Call t

ollfr ee 1-800-858-7378, betw een 8:00 am and 6:00 pm Centr al T ime , Monda y thr ough F rida

y .