BARQUAT 50-65A

BARQUAT 50-65A

CAS NO: 68424-85-1
EC NO: 939-253-5

SYNONYMS:

C12-16-benzalkonium chloride; Quaternary ammonium compounds, benzyl-C12-16-alkyldimethyl, chlorides; Hyamine 3500; Quaternary ammonium compounds, benzyl C12-16 (even numbered)-alkyldimethyl chlorides; benzalkonium chloride(C12-C-16); N-Alkyl-N-benzyl-N,N-dimethylammonium chloride; Alkyldimethylbenzylammonium chloride; ADBAC; BC50 BC80; Quaternary ammonium compounds; quats; Benzalkonium chloride; BZK; BKC; BAK; BAC; alkyldimethylbenzylammonium chloride (ADBAC); 0W255OL75T; 139-08-2 [RN]; 205-352-0 [EINECS]; 269-919-4 [EINECS]; 270-325-2 [EINECS]; 4062599; 4663; 68424-85-1 [RN]; Benzenemethanaminium, N,N-dimethyl-N-tetradecyl-, chloride 1:1); Benzyldimethyltetradecylammonium Chloride; Benzyltetradecyldimethylammonium chloride; N-Benzyl-N,N-dimethyl-1-tetradecanaminium chloride; n-benzyl-n,n-dimethyltetradecan-1-aminium chloride; Zephirol Related Compound 1; [139-08-2]; 1-(2-methoxyphenyl)propan-2-amine; 10328-34-4 [RN]; 1219178-72-9 [RN]; 122-18-9 [RN]; 14BCL; 60484-28-8 [RN]; 85409-22-9 [RN]; 89004-36-4 [RN]; Acinol; Ammonium, benzyldimethylhexadecyl-, chloride; Ammonium, benzyldimethyltetradecyl-, chloride; Ammonium, benzylhexadecyldimethyl-, chloride; Ammonyx G [Trade name]; Ammonyx T [Trade name]; Arquad DM 14B90; Arquad DM14B-90; Baktonium; Banicol; Barquat MB 50; Barquat MS 100; Benzaletas; Benzenemethanaminium, N,N-dimethyl-N-tetradecyl-, chloride; Benzenemethanaminium, N-hexadecyl, N,N-dimethyl-, chloride; Benzenemethanaminium, N-hexadecyl-N,N-dimethyl-, chloride; Benzyl(tetradecyl)dimethylammonium Chloride; benzyl-cetyl-dimethyl-ammonium chloride; Benzylcetyldimethylammonium chloride; Benzyldimethylcetylammonium chloride; benzyl-dimethyl-myristyl-ammonium chloride; Benzyldimethylmyristylammonium chloride; Benzyl-dimethyl-tetradecyl-ammonium; benzyl-dimethyl-tetradecylammonium chloride; benzyl-dimethyl-tetradecyl-ammonium chloride; Benzyldimethyltetradecylammonium chloride dihydrate; Benzyldimethyltetradecylammonium chloride, anhydrous; benzyl-dimethyl-tetradecyl-ammonium chloride; Benzyldimethyltetradecylammoniumchloride; Benzyldimethyltetradecylammonium-d7 Chloride; benzyl-dimethyl-tetradecylazanium; benzyl-dimethyl-tetradecylazanium and chloride; benzyl-dimethyl-tetradecylazanium chloride; BENZYLDIMETHYLTETRADECYLAZANIUM CHLORIDE; benzyl-dimethyl-tetradecylazanium;chloride; benzyl-hexadecyl-dimethylammonium chloride; benzyl-hexadecyl-dimethyl-ammonium chloride; benzyl-hexadecyl-dimethylazanium chloride; TC 824P100; Cation M2-100; Cdbac; Cetyl dimethyl benzyl ammonium chloride; Cetyl zephiran; Cetylbenzyldimethylammonium chloride; Cetylon; CHLORIDE TETRADECYL DIMETHYL BENZYL AMMONIUM;  Dehyquart CBB; Dehyquart CDB; Dibactol; dimethyl-(phenylmethyl)-tetradecylammonium chloride; dimethyl-(phenylmethyl)-tetradecyl-azanium chloride; Dimethylbenzylcetylammonium chloride; Dimethylbenzylhexadecylammonium chloride; Dimethylbenzylmyristylammonium chloride; dimethylbenzyltetradecylamine, chloride; Dimethylbenzyltetradecylammonium chloride; Dmcbac; EINECS 204-526-3; EINECS 205-352-0; Faringets; Hexadecylbenzyldimethylammonium chloride; hexadecyl-dimethyl-(phenylmethyl)azanium chloride; Hexadecyldimethylbenzylammonium chloride; Myristyl dimethyl benzyl ammonium chloride; MYRISTYLDIMETHYLBENZYLAMMONIUM CHLORIDE; N,N-Dimethyl-N-tetradecylbenzenemethanaminium chloride; N-Benzyl-N,N-dimethyltetradecan-1-aminiumchloride; N-Benzyl-N-cetyldimethylammonium chloride; N-Benzyl-N-tetradecyldimethylammonium chloride; n-Hexadecyldimethylbenzylammonium chloride; N-Hexadecyl-N,N-dimethylbenzenemethanaminium chloride; N-HEXADECYL-N,N-DIMETHYLBENZENEMETHANAMINIUM CL; Nissan Cation M2 100; Nissan cation M2-100; N-tetradecyl-N-benzyl-N,N-dimethylammonium chloride; N-tetradecyl-N-benzyl-N,N-dimethylammonium chloride;  Quarton 14 BCL; Quarton 14BCl; Quaternario 14B; Querton 14BCL; Rodalon; Sanibond 200lg; Sanisol M 100; Spilan; Tetradecyl dimethyl benzyl ammonium chloride; Tetradecylbenzyldimethylammonium chloride; Tetradecyldimethylbenzylammonium chloride; Tetradecyl-dimethyl-benzylammonium chloride; Tetraseptan; Trimethyl tetradecylphenyl ammonium chloride; UNII:0W255OL75T; UNII-0W255OL75T; UNII-F5UM2KM3W7; Quaternary ammonium compounds, benzyl-C12-16-alkyldimethyl, chlorides; Ammonium, alkyl(C12-C16)dimethylbenzyl-, chlorides; Alkyl(40%C12,50%C14,10%C16)dimethylbenzylammonium chloride; Alkyl(40%C12,50%C14,10%C16) dimethyl benzyl ammonium chloride; Hyamine; Alkyl(C12-16)dimethylbenzylammonium chloride; Quaternary ammonium compounds, benzyl-C12-16-alkyldimethyl, chlorides; Benzyl-C12-C16-alkyldimethyl ammonium chlorides; Alkyl(C12-C16) dimethylbenzyl-, chlorides; Quaternary ammonium compounds, benzyl- C12-16- alkyldimethyl, chlorides; (((2-Hydroxy-3-methoxybenzylidene)hydrazino)carbonylmethylene)trimethylammonium chloride; 6958-21-0; (((3,4,5-Trimethoxybenzylidene)hydrazino)carbonylmethylene)-trimethylammonium chloride; 101710-71-8; (((6-Chloro-o-tolyl)carbamoyl)methyl)dimethyl((phenylcarbamoyl)methyl)ammonium chloride; 4061-36-3; (((Heptadecafluorooctyl)sulphonyl)amino)propyl)trimethylammonium chloride; 38006-74-5; ((1)-11H-Dibenzo(b,e)(1,4)dioxepin-11-ethyl)di(methyl)ammonium chloride; 85392-12-7; ((2,4-Dichlorophenoxy)methyl)dimethyloctylammonium chloride 93840-58-5; ((2-Bromoethoxy)ethoxyphosphin-1-yl)trimethylammonium chloride 91772-29-1; ((3-Allyloxy-2-hydroxy)propyl)trimethylammonium chloride; 69613-89-4; ((9-Methoxy-7-oxo-7H-furo(3,2-g)(1)benzopyran-4-yl)methyl)trimethylammonium chloride; 96616-39-6; ((Diethylcarbamoyl)methyl)diethyl((mesitylcarbamoyl)methyl)ammonium chloride; 79143-73-0; ((Dodecyloxy)methyl)-tris(2-hydroxyethyl)ammonium chloride; 75839-68-8; (1,3-Dioxo-2-(p-methoxyphenyl)indan-2-yl(methoxycarbonyl)methyl)trimethylammonium chloride; 42223-07-4; (10-Hydroxydecyl)trimethylammonium chloride carbamate; 63981-62-4; (2-((2-Chloroethyl)thio)ethyl)trimethylammonium chloride, hydrochloride; (2-((2-Cyano-3-(4-(diethylamino)phenyl)-1-oxoallyl)oxy)ethyl)(3-hydroxypropyl)dimethylammonium chloride; 93981-79-4; (2-((2-Cyano-3-(4-(ethylbenzylamino)phenyl)-1-oxoallyl)oxy)ethyl)trimethylammonium chloride; 71550-24-8; (2-((2-Hydroxy-1-(hydroxymethyl)-2-(4-nitrophenyl)ethyl)amino)-2-oxoethyl)trimethylammonium chloride; 93857-08-0; (2-((4-((2-Chloro-4-nitrophenyl)azo)-3-methylphenyl)ethylamino)ethyl)trimethylammonium chloride; 85392-24-1; (2-((4-((2-Cyano-4-nitrophenyl)azo)phenyl)ethylamino)ethyl)trimethylammonium chloride; 37672-77-8; (2-((alpha-Cyano-p-(diethylamino)cinnamoyl)oxy)ethyl)trimethylammonium chloride; 64992-16-1; (2-(2,5-Dimethoxyphenyl)-1-methyl-2-oxoethylidene)hydroxyammonium chloride; 93942-52-0; (2-(2-Hydroxy-3-((1-oxooctadecyl)oxy)propoxy)-2-oxoethyl)dimethyloctadecylammonium chloride; 85153-32-8; (2-(3-Acetyl-2-methyl-1-indolizinyl)-2-methylethyl)dimethyl(1,4-xylyl)ammonium chloride; 66967-61-1; (2-(Acetoxy)ethyl)-3-((2-cyano-3-(4-(diethylamino)phenyl)-1-oxoallyl)oxy)propyldimethylammonium chloride; 93981-89-6; (2-(Acryloyloxy)-1-methylethyl)benzyldimethylammonium chloride; 93941-91-4; (2-(Acryloyloxy)ethyl)(carboxymethyl)diethylammonium chloride, sodium salt; 45168-72-7; (2-(Benzyloxy)ethyl)trimethylammonium chloride; (2-(Ethyl(4-((4-nitrophenyl)azo)phenyl)amino)ethyl)trimethylammonium chloride; 57210-34-1; (2-(Methacryloyloxy)ethyl)dimethyl((2-oxoimidazolidin-1-yl)ethyl)ammonium chloride; 93919-30-3; (2-(p-((2,6-Dichloro-4-nitrophenyl)azo)-N-ethylanilino)ethyl)trimethylammonium chloride; 71033-12-0; (2,3-Dihydroxypropyl)bis(hydroxyethyl)tallowalkylammonium chloride; 70025-19-3; (2,3-Dihydroxypropyl)triethylammonium chloride; 35648-99-8; (2,3-Dihydroxypropyl)triethylammonium chloride, dibenzoate; (2,3-Dihydroxypropyl)trimethylammonium chloride, dibenzoate; (2,3-Dihydroxypropyl)tripentylammonium chloride; (2,3-Dihydroxypropyl)tripentylammonium chloride, dibenzoate; (2,3-Dihydroxypropyl)tripropylammonium chloride; (2,3-Dihydroxypropyl)tripropylammonium chloride, dibenzoate; (2,3-Epoxypropyl)(2-(methacryloyloxy)ethyl)dimethylammonium chloride; 62351-05-7; (2,3-Epoxypropyl)dimethyl(3-((16-methylheptadecanoyl)amino)propyl)ammonium chloride; 94349-35-6; (2,3-Epoxypropyl)ethylbis(2-hydroxyethyl)ammonium chloride; 94213-21-5; (2,4-Dichlorobenzyl)dimethyl(3-((1-oxododecyl)amino)propyl)ammonium chloride; 84697-06-3; (2,4-Dichlorobenzyl)dimethyl(3-((1-oxooctadecyl)amino)propyl)ammonium chloride; 84697-07-4; (2,4-Dichlorobenzyl)dimethyl(3-((1-oxotetradecyl)amino)propyl)ammonium chloride; 94279-05-7; (2,5-Dimethoxy-beta-hydroxy-beta-methylphenethyl)trimethylammonium chloride; 63977-44-6; (2,5-Dimethoxy-beta-hydroxyphenethyl)trimethylammonium chloride; 63977-45-7; (2-Acetimidoxy)ethyltrimethylammonium; 73264-87-6; (2-Benziloyloxyethyl)diethylmethylammonium chloride; 1166-85-4; (2-Benziloyloxyethyl)dimethylisopropylammonium chloride; 64048-33-5; (2-Carboxyethyl)trimethylammonium chloride; 6340-41-6; (2-Chloro-3-hydroxypropyl)trimethylammonium chloride; 25364-86-7; (2-Chloroethyl)dibenzylhydroxyammonium chloride; 66902-80-5; (2-Chloroethyl)dimethyl(2-hydroxyethyl)ammonium chloride; 23165-18-6; (2-Cyanoethyl)trimethylammonium chloride; 82317-52-0; (2-Ethoxyethyl)trimethylammonium chloride; 6343-89-1; (2-Ethylhexyl)dimethyloctylammonium chloride; 94277-44-8; (2-Hydroxy-3-(((1-oxoallyl)amino)methoxy)propyl)trimethylammonium chloride; 94110-15-3; (2-Hydroxy-3-((1-oxoisooctadecyl)oxy)propyl)trimethylammonium chloride; 94689-36-8; (2-Hydroxy-3-((1-oxooctadecyl)oxy)propyl)dimethyl(3-((1-oxooctadecyl)amino)propyl)ammonium chloride; 93981-10-3; (2-Hydroxy-3-(4'-dodecylphenoxy)propyl)trimethylammonium chloride; 68413-50-3; (2-Hydroxy-3-(tetradecyloxy)propyl)dimethyl(2-((2-methyl-1-oxoallyl)oxy)ethyl)ammonium chloride; 93942-68-8; (2-Hydroxy-3-chloropropyl)octadecyldimethylammonium chloride; 3001-63-6; (2-Hydroxyethyl)(11-((2-hydroxyphenethyl)methylamino)undecyl)methylphenacylammonium chloride; 82866-92-0; (2-Hydroxyethyl)(1-hydroxy-1-methylethyl)dimethylammonium chloride; 85909-54-2; (2-Hydroxyethyl)(2-hydroxyhexadecyl)dimethylammonium chloride; 84643-53-8; (2-Hydroxyethyl)(3-hydroxypropyl)dimethylammonium chloride; 78182-00-0; (2-Hydroxyethyl)dimethyl(3-(((3-oxo-3H-naphtho(2,1-b)pyran-2-yl)carbonyl)amino)propyl)ammonium chloride; 94159-27-0; (2-Hydroxyethyl)methyldioleylammonium chloride; 96837-05-7; (2-Hydroxyethyl)octadecylammonium chloride; 94313-61-8; (2-Hydroxyethyl)triethylammonium chloride; 152-22-7; (2-Hydroxyethyl)triethylammonium chloride, benzoate; (2-Hydroxyethyl)tripentylammonium chloride; (2-Hydroxyethyl)tripropylammonium chloride; 96311-53-4; (2-Hydroxyhexadecyl)trimethylammonium chloride; 82711-88-4; (2-Hydroxypropyl)methyldioctadecylammonium chloride; 94278-98-5; (2-Hydroxypropyl)trimethylammonium chloride; 2382-43-6; (2-Stearamidoethyl)bis(2-hydroxyethyl)methylammonium chloride; 73398-95-5; (3-((2-Cyano-3-(4-(diethylamino)phenyl)-1-oxoallyl)oxy)propyl)(2-hydroxyethyl)dimethylammonium chloride; 93981-78-3; (3-(1,1,2,2-Tetrahydroperfluoro(C6-C20)alkylthio)-2-hydroxypropyl)trimethylammonium chloride; 70983-60-7; (3-(1-Cyclohexylphenoxy)-2-hydroxypropyl)isopropyldimethylammonium chloride; 83514-04-9; (3-(2-Chloro-phenothiazin-10-yl)propyl)dimethyloctylammonium chloride; (3-(2-Chlorophenothiazin-10-yl)propyl)trimethylammonium chloride; 19694-29-2; (3-(Dimethylamino)-2-(4-pyridyl)allylidene)dimethylammonium chloride monohydrochloride; 78448-41-6; (3-(Dodecyloxy)-2-hydroxypropyl)diethyl(2-((1-oxoallyl)oxy)ethyl)ammonium chloride; 93804-70-7; (3-(Dodecyloxy)-2-hydroxypropyl)diethyl(2-((2-methyl-1-oxoallyl)oxy)ethyl)ammonium chloride; 94086-81-4; (3-(Dodecyloxy)-2-hydroxypropyl)diethylmethylammonium chloride; 71929-11-8; (3-(Dodecyloxy)-2-hydroxypropyl)dimethyl(2-((2-methyl-1-oxoallyl)oxy)ethyl)ammonium chloride; 93942-69-9; (3-(Ethyl(o-tolyl)amino)-2-hydroxypropyl)trimethylammonium chloride; 56280-59-2; (3-(o-Bromobenzyl)-2-butenyl)diethyl(heptyloxycarbonylmethyl)ammonium chloride; 62988-54-9; (3-(o-Bromobenzyl)-2-butenyl)diethyl(hexyloxycarbonylmethyl)ammonium chloride; 62988-53-8; (3-Amino-4-methoxybenzyl)bis(3-(formylamino)propyl)methylammonium chloride; 40948-32-1; (3-Behenoyloxy-2-hydroxypropyl)trimethyl ammonium chloride; 69537-38-8; (3-Benziloyloxypropyl)diethylmethylammonium chloride; 64048-34-6; (3-Benziloyloxypropyl)dimethylethylammonium chloride; 64048-35-7; (3-Benzyl-2-butenyl)(carboxymethyl)diethylammonium chloride, decyl ester; 57757-50-3; (3-Benzyl-2-butenyl)(carboxymethyl)dimethylammonium chloride, heptyl ester; 73680-64-5; (3-C(12-13)-Alkoxy-2-hydroxypropyl)triethylammonium chloride; 72968-32-2; (3-Carbamoyl-3,3-diphenylpropyl)diethylpropylammonium chloride; (3-carbamoyl-3,3-diphenylpropyl)diisopropylmethylammonium chloride; 24353-18-2; (3-Carboxy-2-hydroxypropyl)trimethylammonium chloride, acetate, (DL)-; 2504-11-2; (3-carboxy-2-hydroxypropyl)trimethylammonium chloride, palmitate; 6819-24-5; (3-Carboxy-2-oxopropyl)trimethylammonium chloride; 94291-69-7; (3-Carboxyallyl)trimethylammonium chloride; 6538-82-5; (3-Chloro-2-hydroxypropyl)(2-hydroxyethyl)dimethylammonium chloride; 84434-68-4; (3-Chloro-2-hydroxypropyl)diethyl(2-((1-oxoallyl)oxy)ethyl)ammonium chloride; 93892-92-3; (3-Chloro-2-hydroxypropyl)diethyl(2-((2-methyl-1-oxoallyl)oxy)ethyl)ammonium chloride; 93804-78-5; (3-Chloro-2-hydroxypropyl)dimethyl(3-(((octadecylamino)carbonyl)amino)propyl)ammonium chloride; 94248-89-2; (3-Chloro-2-hydroxypropyl)triethylammonium chloride; 35649-00-4; (3-Chloro-2-hydroxypropyl)triethylammonium chloride, acetate; (3-Chloro-2-hydroxypropyl)triethylammonium chloride, benzoate; (3-Chloro-2-hydroxypropyl)trimethylammonium chloride, acetate; (3-Chloro-2-hydroxypropyl)trimethylammonium chloride, benzoate; (3-Chloro-2-hydroxypropyl)tripentylammonium chloride; (3-Chloro-2-hydroxypropyl)tripentylammonium chloride, acetate; (3-Chloro-2-hydroxypropyl)tripentylammonium chloride, benzoate; (3-Chloro-2-hydroxypropyl)tripropylammonium chloride; (3-Chloro-2-hydroxypropyl)tripropylammonium chloride, acetate; (3-Chloro-2-hydroxypropyl)tripropyl-ammonium chloride, benzoate; (3-Cyano-2-hydroxypropyl)trimethylammonium chloride; 18933-33-0; (3-Cyano-2-hydroxypropyl)trimethylammonium chloride, (DL)-; 5238-52-8; (3-Cyano-2-hydroxypropyl)trimethylammonium chloride, D-; 1116-95-6; (3-Cyano-2-hydroxypropyl)trimethylammonium chloride, L-; 2788-28-5; (3-Cyanopropyl)trimethylammonium chloride; (3-Hydroxypropyl)trimethylammonium chloride, acetate; 16332-31-3; (3-Hydroxypropyl)trimethylammonium chloride; 6701-82-2; (3-Methacrylamidopropyl)trimethylammonium chloride, homopolymer; 61181-02-0; (4-((2-Chlorophenyl)(1-methyl-2-phenyl-1H-indol-3-yl)methylene)-2,5-cyclohexadien-1-ylidene)diethylammonium chloride; 72828-90-1; (4-((4-(Bis(2-hydroxyethyl)amino)-o-tolyl)(4-(dimethylamino)phenyl)methylene)cyclohexa-2,5-dien-1- ylidene)dimethylammonium chloride; 83950-33-8; (4-((4-(Diethylamino)-2-methylphenyl)azo)phenacyl)trimethylammonium chloride; 67905-12-8; (4-((4-(Diethylamino)phenyl)(4-((4-ethoxyphenyl)amino)-1-naphthyl)methylene)-2,5-cyclohexadien-1- ylidene)diethylammonium chloride; 73309-46-3; (4-((4-(Dimethylamino)-o-tolyl)(4-(dimethylamino)phenyl)methylene)cyclohexa-2,5-dien-1- ylidene)dimethylammonium chloride; 6527-75-9; (4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium chloride; 55-45-8; (4-Acetamidophenacyl)trimethylammonium chloride; 52018-82-3; (4-Amino-2-hydroxybutyl)trimethylammonium chloride, hydrochloride; (4-Anilino-2,4-dioxobutyl)trimethylammonium chloride; 85005-65-8; (4-Chloro-2-butenyl)trimethylammonium chloride; 4237-07-4; (4-Chloro-2-butynyl)dimethylhexadecylammonium chloride; 73663-98-6; (4-Hydroxy-2-butenyl)trimethylammonium chloride m-chlorocarbanilate; 13681-36-2; (5alpha,9alpha,11S')-(2,3-Dichloro-5,6,9,10-tetrahydro-5,9-methanobenzocycloocten-11-yl)methylammonium chloride; 85750-25-0; (5-Indolyl)trimethylammonium chloride

BARQUAT 50-65A

Barquat® 50-65A is a blend of alkyl dimethyl benzyl ammonium chlorides. When used as an active ingredient in FIFRA registered formulations such as hard surface disinfectants, sanitizers and/or certain types of water treatment formulations, these products have been found to provide superior biocidal action against a broad spectrum of microbial organisms such as: bacteria, fungi, viruses, and algae. This “first generation” quaternary ammonium compound delivers potent germicidal action in most applications.

Disinfectants are the chemical agents that either inhibit microbial activities and growth or are lethal and kill the microorganisms. In man’s struggle to control the microbes responsible for disease and illness many organic and inorganic chemicals have been found to be toxic to microorganisms.

N-alkyl ethylbenzyl dimethyl ammonium (c12-c14) is a quaternary ammonium compound with surfactant properties. It is found in sanitizing solutions or soaps as an active ingredient due to its antimicrobial properties.

Employed in a great variety of cleaning agents and sanitizing agents, it possesses relatively broad gram-positive and gram-negative antibacterial activities and relatively little chance for systemic absorption and exposure, although the formal mechanism of action of quaternary ammonium compounds like n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride is difficult to elucidate.

N-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride is a quaternary ammonium compound that demonstrates antimicrobial activity. In particular, a high degree of microbiocidal activity in hard water is obtained with a blend of two quaternary ammonium chlorides or bromides where the quaternary ammonium cation of each quaternary component is alkyl dimethyl ethylbenzyl and wherein the the alkyl group in once case is C12 and in the other case is C14, with these compounds being present only within the range of 85/15 to 55/45 of the C12 compound relative to the C14 compound.

Quaternary ammonium compounds like n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride have subsequently shown antimicrobial activity against both gram positive and negative bacteria as well as a certain extent of antifungal activity and certain actions against particular virus types.

As a component of cleaning agents and disinfectants, topical exposure is largely the most common form of n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride exposure to humans. Regardless, when the agent is in contact with human skin, percutaneous absorption through intact skin is believed to be minimal, and so systemic effects from topical exposure is expected to be rare.

Quaternary ammonium compounds like n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride irreversibly bind to the phospholipids and proteins of microbial cell membranes, thereby impairing membrane permeability. Consequently, the antibacterial actions of n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride generally stem from the capacity of bacterial cells to absorb the compound, causing the disruption or dissociation of cellular membrane lipid bilayers of bacteria, resulting in compromised cellular permeability control and the leakage of important cellular contents. In particular, the antimicrobial activity of quaternary ammonium with an alkyl chain is related to lipolhilia and peaks between C12 and C16 for both gram-positive and gram-negative bacterial strains. Specifically, in gram-positive bacteria, the agent becomes bound to the wall proteins and is, therefore, able to enter and destroy the membrane. Additionally, in some microbes, n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride can cause a leak in metabolites with low molecular weights, resulting in metabolic injury and modification of permeability for the microbe.

It is for these aforementioned mechanisms of action that n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride is capable of eliciting antimicrobial activity when used as a disinfectant. However, when used as an agent for routine cleaning where surface contamination with pathogenic bacteria and viruses does not necessarily present a hazard, the use of n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride and its antimicrobial actions may not be entirely necessary or recommended, considering quaternary ammonium compounds like n-alkyl C12-C14 dimethyl ethylbenzyl ammonium chloride can persist on cleaned surfaces and contribute to prolonged topical exposure to individuals.

Quaternary ammonium compounds are poorly absorbed by the oral route of administration. At the same time, systemic effects from percutaneous absorption through intact skin is considered rare as well. Nevertheless, although potentially minimal, systemic absorption is possible.

Quats (quaternary ammonium compounds) are potent disinfectant chemicals commonly found in disinfectant wipes, sprays and other household cleaners that are designed to kill germs. It is often the stuff that allows a product to claim to be antibacterial, as they are certified by the EPA as pesticides.

Quaternary ammonium compounds (QACs) are sometimes referred to as quats. These compounds are among the most commonly used disinfectants in the food industry, and there are numerous commercially available products and formulations. They are cationic surfactants (positively charged surface-active agents) that impact cell walls and membranes after relatively long contact times. Their permanent positive charge makes them bind readily to the negatively charged surface of most microbes. QACs are used at concentrations ranging from 200 to 400 ppm for various food-contact surfaces. QACs are generally very stable, mostly unaffected by pH levels, and remain effective on a food-contact surface for a long time. Their antimicrobial activity is more selective than that of other disinfectants, they are inactivated by organic soil, and they should not be diluted in hard water. QACs are, however, generally very effective against bacterial biofilms. An example of a QAC is benzalkonium chloride, which is often used as a cleaner and sanitizer for various food surfaces, both at home and in industrial applications such as dairy equipment.

Quaternary ammonium compounds (commonly known as quats or QACs) are cationic surfactants (surface active agents) that combine bactericidal and virucidal (generally only enveloped viruses) activity with good detergency and, therefore, cleaning ability. Although other surfactant types, such as anionic, nonionic and, amphoteric surfactants (referring to their overall charge) have some antimicrobial activity depending on the specific biocide, the cationic surfactants (and some of the amphoterics) have the greatest antimicrobial activity. Examples include hexadecyltrimethylammonium (‘cetrimide’), chlorhexidine, and benzalkonium chloride. As for other biocides, the activity of QAC-based formulations will vary significantly based on the types of biocides used and their respective formulations. Given that their primary mechanism of action is the structure/function disruption against cell membranes, they generally demonstrate bactericidal and fungicidal activity, with further activity observed against enveloped viruses. QACs are also potent microstatic (including sporistatic) agents, but only limited formulations have claimed activity against mycobacteria (presumably by combination of other formulation excipients that allow greater penetration of the mycobacterial cell wall structure) and are generally cited as being nonactive against nonenveloped viruses. Activity can be affected by the presence of water hardness (when used to dilute a concentrated product), fat-containing substances, and anionic surfactants. QACs have a pleasant odor, are not aggressive on surfaces, and have low toxicity. They are widely used as cleaners/disinfectants on general, noncritical surfaces, including the removal of gross soil. QACs and other surfactants are also used as preservatives (e.g., in paints and cosmetics). Some QACs and amphoterics are also used at low concentrations as antiseptics. The most widely used ones are the biguanides and in particular chlorhexidine (chlorhexidine gluconate, CHG) and polymeric biguanides (e.g., Vantocil). CHG is used in such products as antimicrobial soaps (e.g., Hibiclens), mouthwashes, wound dressings, and in contact lens storage solutions. In these applications, in addition to direct antimicrobial activity, CHG has the further benefits of low irritation and binding to, and remaining on, the skin and mucous membranes at low, bacteristatic concentrations following application (thereby providing longer term or ‘substantive’ antimicrobial protection). In addition to antiseptic applications, the polymeric bioguanides are also used as general disinfectants and for water sanitization (as chlorine alternatives). Overall, the antimicrobial activity of CHG and the polymerics are similar to other QACs, but have limited fungicidal activity in their own right that can be enhanced in formulation but are fungistatic and sporistatic at low concentrations. As for the QACs, the cell membrane is the main target for antimicrobial activity and the action of CHG in particular has been well studied. Being positively charged, they are rapidly attracted to the cell wall surface, with initial surface structure disruption, penetration to the cell membrane, and direct insertion to and interaction with the phospholipids, leading to structure/function disruption (including leakage of cytoplasmic components); these effects culminate in cell death and loss of viability of enveloped viruses.

Quaternary ammonium compounds are surface-active agents. Some of them precipitate or denature proteins and destroy microorganisms. The most important disinfectants in this group are cationic surface-active agents, such as benzalkonium chloride, benzethonium chloride and methylbenzethonium chloride, and cetylpyridinium chloride; the problems that they cause are similar.

Benzalkonium chloride is composed of a mixture of alkyldimethylbenzylammonium chlorides. The hydrophobic alkyl residues are paraffinic chains with 8–18 carbon atoms. Benzalkonium chloride is used as a preservative in suspensions and solutions for nasal sprays and in eye-drops. Depending on the concentration of the solution, local irritant effects can occur. In nasal sprays it can exacerbate rhinitis and in eye-drops it can cause irritation or keratitis.

Quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure NR+4, R being an alkyl group or an aryl group. Unlike the ammonium ion (NH+4) and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged, independent of the pH of their solution. Quaternary ammonium salts or quaternary ammonium compounds (called quaternary amines in oilfield parlance) are salts of quaternary ammonium cations. Polyquats are a variety of engineered polymer forms which provide multiple quat molecules within a larger molecule.

Quaternary ammonium compounds are prepared by the alkylation of tertiary amines with a halocarbon. In older literature this is often called a Menshutkin reaction, however modern chemists usually refer to it simply as quaternization. The reaction can be used to produce a compound with unequal alkyl chain lengths; for example when making cationic surfactants one of the alkyl groups on the amine is typically longer than the others. A typical synthesis is for benzalkonium chloride from a long-chain alkyldimethylamine and benzyl chloride:

CH3(CH2)nN(CH3)2 + ClCH2C6H5 → [CH3(CH2)nN(CH3)2CH2C6H5]+Cl−

Quaternary ammonium salts are used as disinfectants, surfactants, fabric softeners, and as antistatic agents (e.g. in shampoos). In liquid fabric softeners, the chloride salts are often used. In dryer anticling strips, the sulfate salts are often used. Older aluminium electrolytic capacitors and spermicidal jellies also contain quaternary ammonium salts.

As antimicrobials

Quaternary ammonium compounds have also been shown to have antimicrobial activity. Certain quaternary ammonium compounds, especially those containing long alkyl chains, are used as antimicrobials and disinfectants. Examples are benzalkonium chloride, benzethonium chloride, methylbenzethonium chloride, cetalkonium chloride, cetylpyridinium chloride, cetrimonium, cetrimide, dofanium chloride, tetraethylammonium bromide, didecyldimethylammonium chloride and domiphen bromide. Also good against fungi, amoebas, and enveloped viruses, quaternary ammonium compounds are believed to act by disrupting the cell membrane or viral envelope. Quaternary ammonium compounds are lethal to a wide variety of organisms except endospores, Mycobacterium tuberculosis and non-enveloped viruses.

Quaternary ammonium compounds are cationic detergents, as well as disinfectants, and as such can be used to remove organic material. They are very effective in combination with phenols. Quaternary ammonium compounds are deactivated by anionic detergents (including common soaps). Also, they work best in soft waters. Effective levels are at 200 ppm. They are effective at temperatures up to 100 °C (212 °F).

Quaternary ammonium salts are commonly used in the food service industry as sanitizing agents.

Phase transfer catalysts

In organic chemistry, quaternary ammonium salts are employed as phase transfer catalysts (PTCs). Such catalysts accelerate reactions between reagents dissolved in immiscible solvents. The highly reactive reagent dichlorocarbene is generated via PTC by reaction of chloroform and aqueous sodium hydroxide.

Fabric softeners and hair conditioners

In the 1950s, distearyldimethylammonium chloride (DHTDMAC), was introduced as a fabric softener. This compound was discontinued because the cation biodegrades too slowly. Contemporary fabric softeners are based on salts of quaternary ammonium cations where the fatty acid is linked to the quaternary center via ester linkages; these are commonly referred to as betaine-esters or ester-quats and are susceptible to degradation, e.g., by hydrolysis. Characteristically, the cations contain one or two long alkyl chains derived from fatty acids linked to an ethoxylated ammonium salt. Other cationic compounds can be derived from imidazolium, guanidinium, substituted amine salts, or quaternary alkoxy ammonium salts. 

Depending on purity, benzalkonium chloride ranges from colourless to a pale yellow (impure). Benzalkonium chloride is readily soluble in ethanol and acetone. Dissolution in water is slow. Aqueous solutions should be neutral to slightly alkaline. Solutions foam when shaken. Concentrated solutions have a bitter taste and a faint almond-like odour.

Standard concentrates are manufactured as 50% and 80% w/w solutions, and sold under trade names such as BC50, BC80, BAC50, BAC80, etc. The 50% solution is purely aqueous, while more concentrated solutions require incorporation of rheology modifiers (alcohols, polyethylene glycols, etc.) to prevent increases in viscosity or gel formation under low temperature conditions.

Benzalkonium chloride also possesses surfactant properties, dissolving the lipid phase of the tear film and increasing drug penetration, making it a useful excipient, but at the risk of causing damage to the surface of the eye.

Laundry detergents and treatments.

Softeners for textiles.

Especially for its antimicrobial activity, benzalkonium chloride is an active ingredient in many consumer products:

•    Pharmaceutical products such as eye, ear and nasal drops or sprays, as a preservative.
•    Personal care products such as hand sanitizers, wet wipes, shampoos, soaps, deodorants and cosmetics.
•    Skin antiseptics and wound wash sprays, such as Bactine.
•    Throat lozenges and mouthwashes, as a biocide
•    Spermicidal creams.
•    Cleaners for floor and hard surfaces as a disinfectant, such as Lysol and Dettol antibacterial spray and wipes.
•    Algaecides for clearing of algae, moss, lichens from paths, roof tiles, swimming pools, masonry, etc.

Benzalkonium chloride is also used in many non-consumer processes and products, including as an active ingredient in surgical disinfection. A comprehensive list of uses includes industrial applications. An advantage of benzalkonium chloride, not shared by ethanol-based antiseptics or hydrogen peroxide antiseptic, is that it does not cause a burning sensation when applied to broken skin. However, prolonged or repeated skin contact may cause dermatitis. 

During the course of the COVID-19 pandemic, from time to time there have been shortages of hand cleaner containing ethanol or isopropanol as active ingredients. The FDA has stated that benzalkonium chloride is eligible as an alternative for use in the formulation of healthcare personnel hand rubs. However, in reference to the FDA rule, the CDC states that it does not have a recommended alternative to ethanol or isopropanol as active ingredients, and adds that "available evidence indicates benzalkonium chloride has less reliable activity against certain bacteria and viruses than either of the alcohols." In November 2020 The Journal of Hospital Infection published a study on benzalkonium chloride formulations; it was found that laboratory and commercial disinfectants with 0.13% to 0.28% inactivated the SARS-CoV-2 virus  within 15 seconds of contact, even in the presence of a soil or hard water. This resulted in a growing consensus that BZK sanitizers are just as effective as alcohol-based sanitizers despite the CDC guidelines. 

Medicine

Benzalkonium chloride is a frequently used preservative in eye drops; typical concentrations range from 0.004% to 0.01%. Stronger concentrations can be caustic[13] and cause irreversible damage to the corneal endothelium. 

Avoiding the use of benzalkonium chloride solutions while contact lenses are in place is discussed in the literature. 

In Russia and China, benzalkonium chloride is used as a contraceptive. Tablets are inserted vaginally, or a gel is applied, resulting in local spermicidal contraception. It is not a failsafe method, and can cause irritation.

Beekeeping

It is used in beekeeping for the treatment of rotten diseases of the brood. 

Adverse effects

Although historically benzalkonium chloride has been ubiquitous as a preservative in ophthalmic preparations, its ocular toxicity and irritant properties, in conjunction with consumer demand, have led pharmaceutical companies to increase production of preservative-free preparations, or to replace benzalkonium chloride with preservatives which are less harmful. 

Many mass-marketed inhaler and nasal spray formulations contain benzalkonium chloride as a preservative, despite substantial evidence that it can adversely affect ciliary motion, mucociliary clearance, nasal mucosal histology, human neutrophil function, and leukocyte response to local inflammation. Although some studies have found no correlation between use of benzalkonium chloride in concentrations at or below 0.1% in nasal sprays and drug-induced rhinitis, others have recommended that benzalkonium chloride in nasal sprays be avoided. In the United States, nasal steroid preparations that are free of benzalkonium chloride include budesonide, triamcinolone acetonide, dexamethasone, and Beconase and Vancenase aerosol inhalers. 

Benzalkonium chloride is irritant to middle ear tissues at typically used concentrations. Inner ear toxicity has been demonstrated. 

Occupational exposure to benzalkonium chloride has been linked to the development of asthma. In 2011, a large clinical trial designed to evaluate the efficacy of hand sanitizers based on different active ingredients in preventing virus transmission amongst schoolchildren was re-designed to exclude sanitizers based on benzalkonium chloride due to safety concerns. 

Benzalkonium chloride has been in common use as a pharmaceutical preservative and antimicrobial since the 1940s. While early studies confirmed the corrosive and irritant properties of benzalkonium chloride, investigations into the adverse effects of, and disease states linked to, benzalkonium chloride have only surfaced during the past 30 years.

Benzalkonium chloride is a human skin and severe eye irritant. It is a suspected respiratory toxicant, immunotoxicant, gastrointestinal toxicant, and neurotoxicant. 

Benzalkonium chloride formulations for consumer use are dilute solutions. Concentrated solutions are toxic to humans, causing corrosion/irritation to the skin and mucosa, and death if taken internally in sufficient volumes. 0.1% is the maximum concentration of benzalkonium chloride that does not produce primary irritation on intact skin or act as a sensitizer.

Poisoning by benzalkonium chloride is recognised in the literature. A 2014 case study detailing the fatal ingestion of up to 8.1 oz (240ml) of 10% benzalkonium chloride in a 78-year-old male also includes a summary of the currently published case reports of benzalkonium chloride ingestion. While the majority of cases were caused by confusion about the contents of containers, one case cites incorrect pharmacy dilution of benzalkonium chloride as the cause of poisoning of two infants. In 2018 a Japanese nurse was arrested and admitted to having poisoned approximately 20 patients at a hospital in Yokohama by injecting benzalkonium chloride into their intravenous drip bags. 

Benzalkonium chloride poisoning of domestic pets has been recognised as a result of direct contact with surfaces cleaned with disinfectants using benzalkonium chloride as an active ingredient.[

The greatest biocidal activity is associated with the C12 dodecyl and C14 myristyl alkyl derivatives. The mechanism of bactericidal/microbicidal action is thought to be due to disruption of intermolecular interactions. This can cause dissociation of cellular membrane lipid bilayers, which compromises cellular permeability controls and induces leakage of cellular contents. Other biomolecular complexes within the bacterial cell can also undergo dissociation. Enzymes, which finely control a wide range of respiratory and metabolic cellular activities, are particularly susceptible to deactivation. Critical intermolecular interactions and tertiary structures in such highly specific biochemical systems can be readily disrupted by cationic surfactants.

Benzalkonium chloride solutions are fast-acting biocidal agents with a moderately long duration of action. They are active against bacteria and some viruses, fungi, and protozoa. Bacterial spores are considered to be resistant. Solutions are bacteriostatic or bactericidal according to their concentration. Gram-positive bacteria are generally more susceptible than gram-negative bacteria. Its activity depends on the surfactant concentration and also on the bacterial concentration (inoculum) at the moment of the treatment. Activity is not greatly affected by pH, but increases substantially at higher temperatures and prolonged exposure times.

In a 1998 study using the FDA protocol, a non-alcohol sanitizer with benzalkonium chloride as the active ingredient met the FDA performance standards, while Purell, a popular alcohol-based sanitizer, did not. The study, which was undertaken and reported by a leading US developer, manufacturer and marketer of topical antimicrobial pharmaceuticals based on quaternary ammonium compounds, found that their own benzalkonium chloride-based sanitizer performed better than alcohol-based hand sanitizer after repeated use. 

Advancements in the quality and efficacy of benzalkonium chloride in current non-alcohol hand sanitizers has addressed the CDC concerns regarding gram negative bacteria, with the leading products being equal if not more effective against gram negative, particularly New Delhi metallo-beta-lactamase 1 and other antibiotic resistant bacteria. 

Newer formulations using benzalkonium blended with various quaternary ammonium derivatives can be used to extend the biocidal spectrum and enhance the efficacy of benzalkonium based disinfection products. Formulation techniques have been used to great effect in enhancing the virucidal activity of quaternary ammonium-based disinfectants such as Virucide 100 to typical healthcare infection hazards such as hepatitis and HIV. The use of appropriate excipients can also greatly enhance the spectrum, performance and detergency, and prevent deactivation under use conditions. Formulation can also help minimise deactivation of benzalkonium solutions in the presence of organic and inorganic contamination.

Benzalkonium chloride degradation follows consecutive debenzylation, dealkylation, and demethylation steps producing benzyl chloride, alkyl dimethyl amine, dimethyl amine, long chain alkane, and ammonia. The intermediates, major, and minor products can then be broken down into CO2, H2O, NH3, and Cl–. The first step to the biodegradation of BAC is the fission or splitting of the alkyl chain from the quaternary nitrogen as shown in the diagram. This is done by abstracting the hydrogen from the alkyl chain by using a hydroxyl radical leading to a carbon centered radical. This results in benzyl dimethyl amine as the first intermediate and dodecanal as the major product. 

From here, benzyl dimethyl amine can be oxidized to benzoic acid using the Fenton process. The trimethyl amine group in dimethylbenzylamine can be cleaved to form a benzyl that can be further oxidized to benzoic acid. Benzoic acid uses hydroxylation (adding a hydroxyl group) to form p-hydroxybenzoic acid. Benzyldimethylamine can then be converted into ammonia by performing demethylation twice, which removes both methyl groups, followed by debenzylation, removing the benzyl group using hydrogenation. The diagram represents suggested pathways of the biodegradation of BAC for both the hydrophobic and the hydrophilic regions of the surfactant. Since stearalkonium chloride is a type of BAC, the biodegradation process should happen in the same manner.

Benzalkonium chloride used as a preservative in nebulised solutions of anti-asthma drugs has been reported to cause dose-related bronchoconstriction especially in asthmatic patients and has been associated with the precipitation of respiratory arrest.

Benzalkonium chlorides (BACs) are chemicals with widespread applications due to their broad-spectrum antimicrobial properties against bacteria, fungi, and viruses. This review provides an overview of the market for BACs, as well as regulatory measures and available data on safety, toxicity, and environmental contamination. We focus on the effect of frequent exposure of microbial communities to BACs and the potential for cross-resistant phenotypes to emerge. Toward this goal, we review BAC concentrations in consumer products, their correlation with the emergence of tolerance in microbial populations, and the associated risk potential. Our analysis suggests that the ubiquitous and frequent use of BACs in commercial products can generate selective environments that favor microbial phenotypes potentially cross-resistant to a variety of compounds. An analysis of benefits versus risks should be the guidepost for regulatory actions regarding compounds such as BACs.

This ingredient is commonly used as a surfactant and antibacterial agent, and is commonly found in household cleaning products.

Benzalkonium chloride has replaced Triclosan as the new “antibacterial” agent in cosmetic and commercial soaps and santizers. The toxicity and dangers triclosan brings to the human body when absorbed via the skin have become commonly known.

Benzalkonium Chloride is primarily used as a preservative and antimicrobial agent, and secondarily used as a surfactant. It works by killing microorganisms and inhibiting their future growth, and for this reason frequently appears as an ingredient in antibacterial hand wipes, antiseptic creams and anti-itch ointments. In cosmetics, its antimicrobial properties are employed to protect products from spoiling. It’s mostly used in personal care products like rash creme, foot odor powder, facial lotion, cleanser, makeup and sunscreen.

Industrial Applications of Benzalkonium Chloride:

Oil & gas : Biocorrosion presents a major operational hazard for the oil and gas production industries. Benzalkonium chloride (BAC 50 & BAC 80) is used to control the activities of sulphate-reducing bacteria (SRB) in sulphate rich waters and cause deposition of ferrous sulphides which causes pitting of steel equipment and pipelines. SRB are also implicated in oil well souring, and responsible for the liberation of toxic H2S gas. Additional applications of benzalkonium chloride include enhanced oil extraction through de-emulsification and sludge breaking.

Manufacture of disinfectants and detergent-sanitisers : On account of its non-toxic, non-corrosive, non-tainting, non-staining characteristics, benzalkonium chloride is the main active use in the formulation of disinfectants and bactericidal sanitisers for healthcare, personal hygiene, the public sector and to safeguard our agriculture and food supply. BAC 50 & BAC 80 allow microbicidal & cleaning properties to be safely incorporated into hygiene products to enhance both penetration and removal of soil & disinfection of surfaces.

Pharmaceuticals & cosmetics : The safety factor of benzalkonium chloride allows its use in a wide range of leave-on skin sanitisers and sanitary baby wipes. BAC 50 is widely used as a preservative in ophthalmic, nasal and aural pharmaceutical preparations as well as to optimise emolliency and substantivity in formulations.

Water treatment : Benzalkonium chloride based formulations are used in water & effluent treatment and algaecides for swimming pools.

Aquaculture : Benzalkonium chloride reduces antibiotic requirement in aquaculture through improved hygiene. BAC is used for water treatment, fish parasite removal, general site disinfection, and infectious disease prevention in fish & shellfish.

Timber protection : Global environmental concern has led to increasing replacement of persistent chlorinated biocides with safer, biodegradable benzalkonium chloride in wood protection. BAC displays excellent fungicidal and algaecidal properties, and is highly effective against other organisms in combination formulations.

Pulp & paper industry : Benzalkonium chloride is used as a general microbicide for slime control & odour management in pulp mills. It improves paper handling and imparts strength & antistatic properties to paper products.

Textile industry : Benzalkonium chloride is used to protect natural fibres from the action of mould and fungi and as a moth repellent. It also acts as a permanent retarder in the dyeing of acrylic fibres with cationic dyestuffs.

Leather industry : Benzalkonium chloride inhibits growth of mould & mildew on hides and facilitates softening, wetting & dyeing of leather.

Horticulture & household : Benzalkonium chloride is highly effective against mould, mildew, moss, fungi & algae and is used for cleaning and preparation of all types of surfaces: greenhouses, roofing, paths, wooden decking, sheds, masonry

Chemical industry : Quaternary ammonium compounds have diverse applications in the chemical industry as precipitant, phase transfer catalyst on account of its ability to localise at oil/water and air/water interfaces, emulsifier/de-emulsifier, etc.

Polymer & coatings : Quaternary ammonium compounds are widely used as anti-static, emulsifier & preservative in the coatings industry (paints, wood treatment, electronics)