| Medications as a Source of Human Exposure to Phthalates Russ Hauser,1,2 Susan Duty,1 Linda Godfrey-Bailey,1 and Antonia M. Calafat3 1Department of Environmental Health, Occupational Health Program, Harvard School of Public Health, Boston, Massachusetts, USA; 2Vincent Memorial Obstetrics and Gynecology Service, Andrology Laboratory and In Vitro Fertilization Unit, Massachusetts General Hospital, Boston, Massachusetts, USA; 3National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA Abstract
Phthalates are a group of multifunctional chemicals used in consumer and personal care products, plastics, and medical devices. Laboratory studies show that some phthalates are reproductive and developmental toxicants. Recently, human studies have shown measurable levels of several phthalates in most of the U.S. general population. Despite their widespread use and the consistent toxicologic data on phthalates, information is limited on sources and pathways of human exposure to phthalates. One potential source of exposure is medications. The need for site-specific dosage medications has led to the use of enteric coatings that allow the release of the active ingredients into the small intestine or in the colon. The enteric coatings generally consist of various polymers that contain plasticizers, including triethyl citrate, dibutyl sebacate, and phthalates such as diethyl phthalate (DEP) and dibutyl phthalate (DBP) . In this article we report on medications as a potential source of exposure to DBP in a man who took Asacol [active ingredient mesalamine (mesalazine) ] for the treatment of ulcerative colitis. In a spot urine sample from this man collected 3 months after he started taking Asacol, the concentration of monobutyl phthalate, a DBP metabolite, was 16,868 ng/mL (6,180 µg/g creatinine) . This concentration was more than two orders of magnitude higher than the 95th percentile for males reported in the 1999-2000 National Health and Nutrition Examination Survey (NHANES) . The patient's urinary concentrations of monoethyl phthalate (443.7 ng/mL, 162.6 µg/g creatinine) , mono-2-ethylhexyl phthalate (3.0 ng/mL, 1.1 µg/g creatinine) , and monobenzyl phthalate (9.3 ng/mL, 3.4 µg/g creatinine) were unremarkable compared with the NHANES 1999-2000 values. Before this report, the highest estimated human exposure to DBP was more than two orders of magnitude lower than the no observable adverse effect level from animal studies. Further research is necessary to determine the proportional contribution of medications, as well as personal care and consumer products, to a person's total phthalate burden. Key words: biomarkers, environmental health, medications, phthalates, reproductive health. Environ Health Perspect 112:751-753 (2004) . doi:10.1289/ehp.6804 available via http://dx.doi.org/ [Online 29 January 2004]
Address correspondence to R. Hauser, Occupational Health Program, Harvard School of Public Health, Building 1, Room 1405, 665 Huntington Ave., Boston, MA 02115 USA. Telephone: (617) 432-3326. Fax: (617) 432-0219. E-mail: rhauser@hohp.harvard.edu We thank M. Silva for the chemical analysis. This study was supported by grants ES09718 and ES00002 from the National Institute of Environmental Health Sciences. The authors declare they have no competing financial interests. Received 16 October 2003 ; accepted 27 January 2004.
The full version of this article is available for free in HTML or PDF formats. |
