UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, DC 20460

OFFICE OF PREVENTION, PESTICIDES, AND TOXIC SUBSTANCES

 

						

March 19, 2008

MEMORANDUM

SUBJECT:	Revised Product Chemistry Chapter for the Tributyltin –
containing Compounds (tributyltin oxide, tributyltin benzoate and
tributyltin maleate) Reregistration Eligibility Decision Document (RED).

TO:	Jill Bloom, Chemical Review Manager, Special Review and
Reregistration Division

	Diane Isbell, Team Leader

	Regulatory Management Branch II

	Antimicrobials Division (7510P)

		

FROM:	Talia Lindheimer, Chemist, Team II

	Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

THRU:	Norm Cook, Branch Chief

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

Case No.: 2620

	Chemical Name								CAS #						PC CODE

	(a) Tributyltin Oxide								56-35-9				   083001	

	(b) Tributyltin Benzoate							4342-36-3				   083106

	(c) Tributyltin Maleate							4027-18-3					083118

Executive Summary

	Tributyltin containing compounds (referred to as TBTOs) are used
primarily as bacteriocides, microbiocides, fungicides, algaecides,
slimacides, virucides, miticides and insecticides.  For purpose of this
re-registration eligibility document, the three chemicals included under
the general classification are: tributyltin oxide (PC Code 083001),
tributyltin benzoate (PC Code 083106), and tributyltin maleate (PC Code
083118).   Examples of some of the primary uses sites in which TBTO
containing products are found include:  agricultural premises and
equipment; oilfield/petrochemical injection water systems; industrial
recirculating water cooling systems; animal kennels, medical premises;
material preservation (textiles, metalworking fluids, plastics,
construction materials, etc); and non-pressure treated wood
preservation.

	Each chemical is identified by an individual CAS number, so product
chemistry information is provided separately for each individual CAS
number.  The values presented in this review have been obtained from the
best available data (in house, EPI Suite, chemfinder, ect.) and can be
further refined with input from the registrants involved in this RED
case.

Chemical Identification for CAS # 56-35-9

Common Name:		Tributyltin Oxide

Chemical Name:		Bis (tributyltin) oxide

Synonyms :			As reported on Cambridgesoft Corporation’s   HYPERLINK
"http://www.chemfinder.com"  www.chemfinder.com , additional names used
to identify this chemical include:  AF-SeafloZ-100; AW 75-D; TBTO;
Tributyltin oxide; Tributyltin oxide ; Tributyltin trioxide;
tri-n-butylstannane oxide; Biomet; Biomet 75; biomet tbto;
bis(tributyloxide) of tin; bis(tributylstannyl) oxide;
Bis(tributyltin)oxide; Bis(tri-n-butyltin)oxide;
Bis(tri-normal-butyltin) oxide; Bis(tri-n-tributyltin)oxide; BTO;
butinox; C-SN-9; HBD; Hexabutlydistannoxane; hexabutyldistannoxane;
hexabutylditin; Interlux Micron; Interswift BKA007; L.S. 3394; Navicote
2000; oxybis(tributyltin); Sigmaplane 7284; Super Sea Jacket; TBOT.

OPP Chemical Code:	083001

Molecular Formula: 	C24H54OSn2 

 

Figure 1:  Chemical structure for Tributyltin Oxide (obtained from  
HYPERLINK "http://www.chemfinder.com"  www.chemfinder.com , also
provided in MRID #400629-01C)

Table 1: Physical/Chemical Properties for Tributyltin Oxide

Parameter	Value	Reference

Molecular Weight	596.12 g/mol	www.chemfinder.com

Density	1.17 g/L	www.chemfinder.com

Boiling Point	417.34oC	EPI Suite

Melting Point	131.93 oC	EPI Suite

Vapor Pressure	7.8 x 10-06 mm Hg @ 25 oC	EPI Suite

Henry’s Law Constant	6.83 x 10-05 atm m3/mol	EPI Suite

log Koc	7.57	EPI Suite

Solubility in Water	0.0896 mg/L	EPI Suite

Half life in Water	2.49 hours (model river)	EPI Suite

Half Life in Air	0.125 days	EPI Suite

log Kow	3.84	EPI Suite

Physical State	Slightly yellow; liquid	www.chemfinder.com



Chemical Identification for CAS # 4342-36-3

Common Name:		Tributyltin Benzoate

Chemical Name:		Stannane, (benzoyloxy)tributyl-

OPP Chemical Codes:	083106

Molecular Formulas: 	C19H32O2Sn

 

Figure 2:  Chemical structure for Tributyltin Benzoate (obtained from  
HYPERLINK "http://www.chemfinder.com"  www.chemfinder.com )

Table 2: Physical/Chemical Properties for Tributyltin Benzoate

Parameter	Value	Reference

Molecular Weight	411.18 g/mol	www.chemfinder.com

Boiling Point	390.12oC	EPI Suite

Melting Point	128.33 oC	EPI Suite

Vapor Pressure	1.34 x 10-06 mm Hg @ 25 oC	EPI Suite

Henry’s Law Constant	2.83 x 10-06 atm m3/mol	EPI Suite

log Koc	5.10	EPI Suite

Solubility in Water	0.257 mg/L	EPI Suite

Half Life in Air	0.241 days	EPI Suite

Half life in water	2.172 hrs (model river)	EPI Suite

log Kow	4.69	EPI Suite

Chemical Identification for CAS # 4027-18-3

There are two CAS numbers affiliated with TBT Maleate, and these are CAS
#4027-18-3 and CAS #14275-57-1.  However, the first number represents
the “mono” form whereas the second represents the “bis” form. 
Historically, the registrations affiliated with TBTM were identified
with CAS #14275-57-1 (bis).  A letter was submitted by the Registrant to
correct this identification because the TBTM active ingredient is the
“mono” form, CAS #4027-18-.  This proposed correction was accepted
by the Agency in 2001 and for this reason, CAS#4027-18-3 was executed in
EPA’s EPISuite Model.  

Common Name:		Tributyltin Maleate 

Chemical Name:		tri-n-butyltin maleate 

OPP Chemical Code:	083118

Molecular Formula:		C16H30O4Sn

Figure 3: Chemical Structure for “mono” tributyltin maleate

Table 3: Physical/Chemical Properties for CAS #4027-18-3

Parameter	Value	Reference

Molecular Weight	405.13 g/mol	EPI Suite

Boiling Point	415.18oC	EPI Suite

Melting Point	153.42oC	EPI Suite

Vapor Pressure	1.74 x 10-07@ 25oC	EPI Suite

Water Solubility	4.086 mg/L	EPI Suite

log Kow	3.79	EPI Suite

log Koc	2.99	EPI Suite

Henry’s Law Constant	1.43 x 10-07atm m3/mol	EPI Suite

Half Life in Water	343.5 days (model river)	EPI Suite

Half Life In Air	2.5 hr	EPI Suite



BIBLIOGRAPHY

MRID #:400629-01C	Goodman, Roy.  Series 61: TBTO Product Identity. 
Completed January 5, 1987.  Project ID TBTO-87-1.

The Estimation Programs Interface (EPI) Suite.  Windows based suite of
physical/chemical properties and environmental estimation models
developed by the US EPA’s Office of Prevention, Pesticides, and Toxic
Substances (OPPTS) and Syracuse Research Institute (SRC).    HYPERLINK
http://www.epa.gov/opptintr/exposure/docs/EPISuitedl.htm 
http://www.epa.gov/opptintr/exposure/docs/EPISuitedl.htm 

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