Occurrence of tin in disposable baby diapers^†

Abstract

Concentrations of tin were measured in six different brands of disposable baby diapers by using radioisotope (americium) excited energy dispersive X-ray fluorescence. Top sheet and adhesive tape system were measured separately. The concentrations found in top sheet and tape system were <1.5 to 23.1 mg/kg and <1.5 to 22.4 mg/kg, respectively. Almost all diapers contained tin in the adhesive tape system (four of five), and two of six samples contained tin in top sheet. Tin found in diapers may be an organotin substance: tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT) and/or dioctyltin (DOT), which are widely used in industrial processes as catalysts or as PVC heat stabilizers. Organotin substances have toxic effects which include neurotoxicity, reproductive and developmental toxicity, immunotoxicity and endocrine disruption. The measured concentrations were less than EU regulatory levels of 0.1% by weight of tin prescribed by REACH Annex XVII No 20. However, the same regulation completely bans the use of organotin substances as biocides in antifouling paints. While effects of TBT on marine organisms from antifouling paints are well known, the effects of organotin compounds in childcare products and other commercial articles receive much less attention. Children who use disposable diapers every day are particularly sensitive. Copyright © 2015 John Wiley & Sons, Ltd.