United States 

Environmental Protection 

Agency 

Tox1c Substances 

Office of 

Toxic Substances 

Washington, DC 20460 

&EPA Toxic Substances 

Control Act 

Chemical Substance 

Inventory _ 

TSCA Inventory: 

1985 Edition 

Volume I 

_, 

January 1986 

TS-793 

EPA-560!7-85-{)02a 
I 

2A 

SDA SUBSTANCE IDENTIFICATION PROCEDURE 

FOR CLASS 2 CHEMICAL SUBSTANCES DERIVED FROM NATURAL 

FATS AND OILS AND SYNTHETIC SUBSTITUTES 

The substance identification system presented here is 

an alternate and relatively simple method which was 

used to identify for the Inventory certain multicomponent 

Class 2 chemical substances derived from natural fats and 

oils and synthetic long-<:hain alkyl substitutes. The system was developed by The Soap and Detergent Associa· 

tion in conjunction with the EPA and is intended to standardize the identification of substances manufactured and used extensively in the soap and detergent 

industry. Accordingly, the system was used to identify 

multicomponent soaps and surface active agents (and also 

their precursors and derivatives) manufactured, imported, or processed for such uses as wetting agents, emulsifiers, dispersants, and penetrants. Its applicability, however, extended beyond the soap and detergent industry. 

This system was not to be used to identify any single 

component Class 1 chemical substance (i.e., a substance 

whose composition may be represented by a definite 

chemical structure diagram) or any combination of such 

substances prepared by mixing without chemical reaction. Furthermore, it was not to be used in those cases 

where the person reporting considered its applicability to 

be marginal or in question. 

The Class 2 chemical substances which were reported 

using this system are complex, multicomponent materials 

whose individual components have a common structural 

feature: one or more long-<:hain alkyl groups to which is 

attached a chemically functional group or groups. These 

components differ from one another with respect tO one or 

more of the following long-<:hain alkyl group characteristics: length (carbon number), saturation, structure (linear 

or branched), and/ or the position of functional group 

attachment(s). 

Under the SDA Substance Identification Procedure, 

certain of these Class 2 chemical substances are identified 

by SDA Substance Names and by corresponding SDA 

Numbers and Substance Definitions. 

SDA SUBSTANCE NAMES 

SDA Substance Names are systematically-derived, and, 

within the limitations of the system, are as precisely 

descriptive of the chemical composition of a substance as 

possible. 

SDA Substance Names consist of two or, in some cases, 

three parts. The two parts common to all SDA Substance 

Names are: (1) the Alkyl Descriptor, A, which describes 

the long-<:hain a lkyl groups of the substance, and (2) the 

Functionality Descriptor, F, which identifies the functional group(s) of the substance. A third part, the Salt 

Descriptor, S, identifies the cation(s) of any salt. 

SDA Substance Names are systematically constructed 

according to the following formats: 

(A) alkyl (F), 

or in the case of salts, 

(A) alkyl (F) (8 ), 

where A denotes the Alkyl Descriptor; F, the Functionality Descriptor; and S, the Salt Descriptor. 

For example, the SDA Substance Name for a fatty amine 

which contains pr~ominantly C, 0 -C, 0 saturated alkyl 

chain-length is: 

C, 0-C11 alkyl amine 

where the phrase "C, 0-C, 0 " corresponds to the Alkyl 

Descriptor (A), and "amine", to the Functionality 

Descriptor (F). 

Similarly, the SlilA Substance Name for the sodium salt 

of a fatty carboxylic acid comprised predominantly of C,8 

saturated and c. a unsaturated alkyl chains is: 

C,8 and C, 8 unsaturated alkyl carboxylic acid sodium 

salt 

where the phrase "C, 8 and C, 8 unsaturated" corresponds to the Alkyl Descriptor (A); "carboxylic acid" to 

the Functionality Descriptor (F); and "sodium salt", to 

the Salt Descriptor (S). 

The Class 2 chemical substances covered by this system 

are limited to those whose composition may be described 

using the Alkyl, Functionality, and Salt Descriptors listed 

below in Tables 1, 2, and 3, respectively. These descriptors, discussed in detail below, can be combined in the 

SDA Substance Name format to describe more than 5,000 

multicomponent Class 2 chemical substances. 

Alkyl Description 

Table I lists the Alkyl Descriptors covered by this 

system of substance identification; assigned to each is a 

two-digit Alkyl Descriptor Code used in generating the 

SDA Reporting Numbers, described later. Each Descriptor identifies a distribution of alkyl groups in terms of 

carbon chain length, saturation and/ or unsaturation, and "linear or branched structure. Alkyl group distributions 

are inclusive of both even and odd alkyl chain lengths. The Descriptors of Table 1 were chosen to cover the 

predominant long-<:hain alkyl group distributions actually present as of 1978, in most commercial multicomponent Class 2 substances of this type, and to provide for 

each as precise a description as practical. Use of this 

sytem is predicated on selecting the narrowest alkyl 

distribution (Alkyl Descriptor) which describes the pre· 

dominant long-chain alkyl groups of the substance reported. In this context, the term "predominant" means that 

about 80 to 100 percent of all long-<:hain alkyl groups are 

included within the description. 

. - '' l 
3A 

In the Alkyl Descriptor, a saturated, linear long-chain 

alkyl group is denoted by "C.'' where the subscript x indicates the number of carbon atoms in the alkyl chain. 

Unsaturated and multiple branched alkyl groups are denoted by ."Cx unsaturated" and "C. branched", respectively. By convention, the number of carbon atoms in a long- chain alkyl group includes all long-chain alkyl and 

functional group carbon atoms, other than those con- tained in an aromatic ring, which are connected to each 

other in a unbroken chain of carbon-carbon-bonds. For example, the alkyl chainlength, designated by "R" in the 

representative structural diagrams found in Table 2, 

includes the acyl carbon of carboxylic acids and their 

derivatives, and the total number of carbon atoms in such 

structures as R-CH2-0H or R-CH:CH2 • The alkyl group 

does not include, however, functional group carbon atoms 

which are part of a phenyl ring, or are separated from the 

alkyl chain by a phenyl group or an atom other than carbon, e.g., R-Ph, R-N(CH3 ) 2 , or R.()(CH2 ) 3NHz. 

Unless specified otherwise, the alkyl groups identified 

by each Alkyl Descriptor are linear, or essentially linear, hydrocarbon chains. The natural fats and oils listed below 

provide such alkyl groups: 

Vegetable 

Avocado 

Babassu 

Castor 

Coconut 

Corn 

Cottonseed 

Cram be 

Linseed 

Olive 

Oiticica 

Palm 

Palm-kernel 

Peanut 

Rapeseed 

Rice Bran 

Safflower 

Safflower 

(high oleic) 

SeSame 

Sorghum 

Soybean 

Sunflower 

Tung 

Wheat Germ 

Animal 

Grease 

Lard 

Neatsfoot 

Poultry 

Tallow 

Marine 

Herring 

Menhaden 

Salmon 

Sardine 

Sperm Body 

(whale) 

Sperm Head 

(whale) 

Whale 

These sources provide both saturated and unsaturated 

alkyl groups; castor oil provides a cl8 hydroxy substituted 

alkyl group. Alkyl groups derived from other natural sources are not covered by this system. 

Synthetic sources can provide linear or essentially 

linear alkyl groups, i.e., chain branching, if any, is limited 

to no more than one secondary methyl (CH3 -) or ethyl 

(C2H$-) group per alkyl chain. For purposes of this system, 

the latter type of alkyl chain is included within the 

designation " linear". Multiple branched alkyl groups, derived exclusively from synthetic sources, have separate 

Alkyl Descriptors. 

Some Class 2 chemical substances covered by this 

procedure are comprised of components which have two or more long-chain alkyl groups, e.g., (dialkyl) amine, or (dialkyl) dimethyl ammonium chloride. This system could 

be used to identify such substances provided that each 

' . , , 

long-chain alkyl group is describable, in its predominant 

composition, by an Alkyl Descriptor found in Table 1 and 

that none of these long-chain alkyl groups is a single 

component structure describable by a defmite chemical 

structural diagram. 

Functionality Description 

Table 2 lists the Functionality Descriptors which could 

be used in this system of substance identification; assigned to each is a three-digit Functionality Descriptor 

Code used in generating SDA Reporting Numbers. The 

partial chemical substance nomenclature (Functionality 

De.scriptors) for each identifies a specific functional group 

or groups. Different Descriptors are provided for salts, 

and for their corresponding acids. 

Associated with each Functionality Descriptor in Table 

2 is a representative structure diagram or diagrams. In 

many cases, these diagrams depict only one of several 

possible isomers of a substance identified by a given 

Functionality Descriptor. For example, a C14-C18 alkyl 

amine identified by this system may contain components 

which have the amine functional group (-NH2 ) attached to a terminal alkyl carbon, as shown in Table 2 for Function· 

ality Descriptor Code 029, or to any other carbon atom in 

the alkyl chain. Th.e applicability and limitations of each 

representative structural diagram are defined by a Substance Definition. (See Substance Definition, below). 

Salt Description 

Table 3 lists the Salt Descriptors covered by this sytem 

of substance identification; assigned to each is a two-digit 

Salt Descriptor Code used in generating the SDA Report· ing Number. SDA Substance Names for Class 2 chemical substance which are not salts contain no Salt Descriptor 

part; t he Salt Descriptor Code for such substances is 00. 

Mixed salts of monovalent anions are considered mix· 

tures of the individual salts, each of which were to be 

identified separately. Mixed salts of divalent anions, 

however could be identified as a single substance. 

SDA REPORTING NUMBER 

The SDA Reporting Number is derived using the two-or 

three-digit codes associated with each Alkyl, Functional· 

ity, or Salt Descriptor contained in Tables 1, 2, and 3. The 

SDA Reporting Number is generated by systematically 

combining these codes for a given substance in a manner similar to that used to derive the SDA Substance Name. SDA Reporting Numbers have the following formats: 

SDA aa-fff-ss or for mixed salts of divalent 

anions, 

SDA aa-fff-ss,s's' 

where "aa" denotes the a ppropriate Alkyl Descriptor 

Code; "fff', the appropriate Functionality Descriptor 

Code; and "ss" (and "s's "') the appropriate Salt Descri~ 

tor Code(s). 

For example, the SDA Reporting Number for CwCu 

alkyl amine is: 

SDA 15-D29-00 

This number was generated using the Descriptor Codes 

found in Tables 1 to 3. Table 1 identifies the Alkyl 

Descriptor Code for "C10-C18": 15. Table 2 identifies the 

Functionality Descriptor Code for "(alkyl). amine": 029. 

Table 3 identifies the Salt Descriptor Code to be used 

when the substance is not a salt: 00. Inserting these 

numbers in the standard format yields the correct SDA 

Reporting Number. 
SUBSTANCE DEFINITION 

Each Functionality Descriptor listed in Table 2 is 

assigned a Substance Defmition Format number ranging 

from 1 to 6. Through this number, the SDA Substance 

Name is linked to one of six generalized Substance 

Definitions appearing in Table 4. For each substance 

reported by this procedure, a unique defmition can be 

generated by inserting the Alkyl, Functionality, and Salt 

Descriptor parts of its SDA Substance Name, and the 

corresponding representative structural diagram found in 

Table 2 into the appropriate generalized Substance Definition. Examples contained in Table 4 illustrate how such 

definitions are generated. The Substance Defi.nitwns 

prouick a chemical description of each substance icknti4A 

[ted by an SDA Substance Name and specify the applicability and limitation of the corresponding representative 

structure diagram. [Note: In Table 4, the term "positional isomers", 

appearing in some Substance Defmitions refers to substances which are otherwise similar except for the 

position of functional group a ttachment(s) on the longchain alkyl group(s).] 

A seven step method, described in Addendum III of the 

Toxic Substances Control Act Candidate List of Chemical 

Substances (March 1978), was useful in applying the · nomenclature of this system to the identification and 

reporting of particular chemical substances. Additional 

examples which further illustrate the applicability and 

limitations of the system are also presented there.