title: Analysis of parabens in dentifrices and the oral cavity.
abstract: This study analyzed levels of parabens in commercial dentifrices and saliva. HPLC was performed using 35% acetonitrile and measuring absorbance at 254 nm. Thirteen toothpastes and five mouthwashes were analyzed. Of these, volunteers used three toothpastes and two mouthwashes, and levels of parabens were analyzed in saliva and water used for mouth rinsing. In toothpastes, the highest concentrations of methylparaben (MP), propylparaben (PP) and n-butylparaben (nBP) were 1.86, 1.42 and 1.87 mg/g, respectively. In mouthwashes, the highest concentrations of MP and PP were 0.97 and 0.11 mg/mL, respectively. After volunteers used 500 mg toothpaste T-1, which contained 895 µg MP, the first and tenth mouth rinse samples contained means of 64.63 and 1.89 µg MP, respectively. After rinsing the mouth three or five times, 37 µg or 18 µg MP was calculated to remain in the oral cavity, respectively. After using 20 mL mouthwash S-1, which contained 19 mg MP, 1.53 mg MP was calculated to remain in the oral cavity. Immediately after using this mouthwash, the mean salivary concentration of MP was 237 µg/mL. The daily intake of parabens from dentifrices was predicted to be insignificant compared with the intake from food; however, parabens can be ingested from dentifrices.
authors.affiliation: Department of Preventive and Social Dentistry, School of Dentistry, Kyung Hee University, Hoegi-dong, Dongdaemoon-gu, Seoul, 130-701, Republic of Korea.
authors.forename: Yong-Duk
authors.initials: YD
authors.lastname: Park
authors.forename: Jong-Hwa
authors.initials: JH
authors.lastname: Jang
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Park
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Eun-Cheol
authors.initials: EC
authors.lastname: Kim
authors.forename: Yun-Jung
authors.initials: YJ
authors.lastname: Song
authors.forename: Ha-Jeong
authors.initials: HJ
authors.lastname: Kwon
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003802:Dentifrices / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D009067:Mouthwashes / Q000737:chemistry; D010226:Parabens / Q000032:analysis*; D015203:Reproducibility of Results; D012463:Saliva / Q000737:chemistry*
chemical_list: D003802:Dentifrices; D009067:Mouthwashes; D010226:Parabens
keywords: HPLC; dentifrice; oral cavity; paraben; saliva