Removal of Dermal Exposure to Phthalate Ester by Hand Washing

Soap and the Removal of Diethylhexyl Phthalate From Hands: N-of-1 and Cross-Over Designs

The aim of the study is to evaluate the effectiveness in removing chemical exposure on hand, the investigators compare removal efficiency of Di-(2-ethylhexyl)phthalate (DEHP) on hands by hand washing with soap and water vs. water only. In two three-day N-of-1 trials, residual DEHP was measured in a single female adult who washed exposed hands with soap-and-water or water-only. Subsequently, a crossover study was performed by randomly assigning another 28 subjects equally to wash with soap-and-water or with water-only, and then each one received the other treatment 24 hrs later.

Study Overview

• Status: Completed
• Conditions: Environmental Exposure; Exposure to Pollution
• Intervention / Treatment: Behavioral: handwashing with soap; Behavioral: handwashing with water

Detailed Description

Three studies, consisting of two N-of-1 trials and one crossover study, were used to compare the effect of handwashing with soap and water (intervention) and handwashing with water only (placebo) on phthalate removal from hands. The soap was plain soap, consisting of vegetable oil and sodium hydroxide. First, the investigators recruited one healthy female aged 25 yrs to participate in two N-of-1 trials. In each trial, her hands would be exposed to DEHP and then be treated with either soap intervention or placebo for three times over the course of three days. The first trial started on 15 May 2013. On day one, after the subject prewashed her hands, she allowed her hands to be exposed to a designated amount of DEHP. She then washed them with water only and rinsed them sequentially in three separate polyethylene (PE) bags, each containing 200 mL water to collect DEHP residue. One hour later, the same protocol was followed, except the exposed hands were treated with soap and water instead of water only (Figure 1a). The water rinsing in three separate bags remained the same. The pairs of studies were repeated on two subsequent days (16 and 17 May).

In the second N-of-1 trial, which was also performed over three days (22-24 May), the protocol using the same subject remained the same for all three days, except that the subject underwent intervention first then placebo. The water rinsing remained the same.

A randomized 2 × 2 crossover study was subsequently conducted between June and September 2013. The investigators assigned one group of 7 females and 7 males to perform handwashing with soap and water (intervention) and another group of 7 females and 7 males to perform handwashing with water only (placebo). Briefly, on the first day, the two groups washed their DEHP exposed hands using either soap and water or water only and then rinsed them in a PE bag with 200 mL water to collect DEHP. After 24 hrs, the experiment was crossed-over with the same two groups receiving the opposite treatments.

• Study Type: Interventional
• Enrollment (Actual): 28
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Taiwan
  • Kaohsiung County
    • Kaohsiung, Kaohsiung County, Taiwan, 807
      • Kaohsiung Medical University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• healthy adult over age of 18 years
• BMI>18

Exclusion Criteria:

• diagnosis of any type of cancers, dermatitis, asthma
• cut, abrasion, and trauma on hands
• BMI <18

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention; Subject was first exposed to 1000 microgram of diethylhexyl phthalate on both hands, and was asked to perform the intervention, handwashing with soap, by a standardized hand washing technique. Then the subjects in this arms are crossover to receive placebo, handwashing with water only.	Behavioral: handwashing with soap; handwashing with soap by a standardized 6-step handwashing technique; Behavioral: handwashing with water; handwashing with water by a standardized 6-step handwashing technique
Placebo Comparator: Placebo; Subject was exposed to 1000 microgram of diethylhexyl phthalate on both hands, and was asked to perform the placebo, handwashing with water, by a standardized hand washing technique. Then the subjects in this arms are crossover to perform the intervention, handwashing with soap.	Behavioral: handwashing with soap; handwashing with soap by a standardized 6-step handwashing technique; Behavioral: handwashing with water; handwashing with water by a standardized 6-step handwashing technique

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Amount of Diethylhexyl Phthalate Removed From Hand	Water rinse were performed immediately after hand-washing, and the concentration of diethylhexyl phthalate in the soiled water is measured.	immediately right after hand-washing

Collaborators and Investigators

• Sponsor: Kaohsiung Medical University Chung-Ho Memorial Hospital
• Investigators: Principal Investigator: Ming-Tsang Wu, ScD, Kaohsiung Medical University

Study record dates

Study Major Dates

• Study Start: May 1, 2013
• Primary Completion (Actual): October 1, 2013
• Study Completion (Actual): December 1, 2013

Study Registration Dates

• First Submitted: March 3, 2016
• First Submitted That Met QC Criteria: March 8, 2016
• First Posted (Estimate): March 14, 2016

Study Record Updates

• Last Update Posted (Actual): October 23, 2018
• Last Update Submitted That Met QC Criteria: September 23, 2018
• Last Verified: September 1, 2018

More Information

Terms related to this study

• Keywords: Cross-Over Studies; Hand hygiene; Soaps; Diethylhexyl Phthalate; N-of-1 design
• Other Study ID Numbers: KMU-PH-201301

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED