Measurement of Skin Irritation of Pampers DryMax

Measurement of Relative Skin Irritation of Pampers Dry Max Disposable Diapers Authors: JEREMI JEREMIAH AH McNICH McNICHOLS, OLS, JENNIF JENNIFER ER McNICH McNICHOLS OLS Published: Z Recommends, July 2010

Introduction The testing of disposable diapers, like that of most other personal care products, is an expensive, intensive, and in many ways exhaustive process. Supplier-produced data sheets guide the selection of materials, and samples sa mples of working and final products are tested on animals, on adult subjects and, in the case of diapers, ultimately on babies during in-home trials. New formulations are also released onto the market for a trial period prior to announcing changes, at least in part to identify id entify and respond to any problems with revised products in as quiet a manner as possible. At the same time, U.S. consumers know much less about what is in disposable diapers than they do about most other products on supermarket shelves. Unlike personal care products like shampoo and toothpaste, the disclosure of ingredients in diapers is not required by law, and the chemicals and materials used in them are typically a closely guarded trade secret. Bleaching agents, surfactants, adhesives, glues, and lotion ingredients include a variety of potential skin irritants, 1 and plastics or lotions may contain any number of potentially harmful ingredients, byproducts, or contaminant contaminants, s, including including dioxin and Tributyl-tin Tributyl-tin2, although the significance of  the levels of these contaminants found in consumer products have been challenged3. Fragrances are employed regionally based on market research, with no indication on packaging of whether the diapers they contain are scented or unscented, and formulations are changed (routinely, some industry representatives have claimed 4) months or years before any announcement is made. The disposable diaper industry is self-policing in its 1. "Disposable diapers: Are Are they dangerous?" CBC News, May 28, 2010. http://bit.ly/ http://bit.ly/ Pampers_CBC 2. "Chronology of findings findings of organotin compounds compounds including TBT (Tributyltin) (Tributyltin) in various non-food consumer products," Mindfully.org. http://bit.ly/Pampers_T http://bit.ly/Pampers_TBT BT 3. "Exposure assessment assessment to dioxins from the the use of tampons and diapers," diapers," Environmental Health Perspectives, January 2002. http://bit.ly/Diapers_Dioxins 4. "Pampers, on the record: record: An interview with with Jodi Allen," Z Recommends, Recommends, July 3, 2010. http://bit.ly/ZRecs_Allen

compliance with existing regulatory standards. This knowledge gap was brought into sharp relief in the latter months of  2009 and the first half of 2010, when an increasing number of consumers began reporting unusual problems with one specific brand of diaper, Pampers, after the company changed the absorbent core to a new formulation it calls "Dry Max." The new core substitutes some of the previously previously used used wood wood pulp for for sodium sodium polyacrylate polyacrylate,, a superabsor superabsorbent bent polymer, polymer, uses an an adhesive adhesive to affix affix the sodium sodium polyacrylate polyacrylate to the interio interiorr surface of the diaper, and uses an additional dye to give the diaper's inner surface a lavender hue. However, the company maintains that its own testing suggests that the new diaper causes no greater incidence or severity of rashes than the previous diaper design. Pampers representatives have maintained to us that diaper rash is caused exclusively by skin exposure to enzymes from bowel movements (BM), deemphasizing the role of chemical exposure, abrasion, or any other diaper feature, but the American Academy of Pediatrics has recently added allergic reactions to diaper materials and chafing or rubbing to its list of possible causes of rashes ranging from mild irritation to open sores 5. Changes to the design and formulation of popular consumer products often lead to a temporary increase in consumer complaints, and companies have learned to account for such events in marketing and evaluating evaluati ng the effectiveness of new products. The result is a deliberate desensitization to consumer complaints during an initial roll-out period, often accompanied by detailed modeling of anticipated responses and their persistence prior to consumer acceptance of the change. This attitude of "weathering the storm" can ensure that customers loyal to an old design have sufficient opportunity to acclimate to changes, and since this period p eriod is often preceded by significant testing and piloting of new products among selected consumers, most companies which engage in such practices are quite confident in their models. The emergence and adoption of new technologies for rapidly sharing inform informatio ation n (Twitt (Twitter, er, Facebo Facebook, ok, Blogger Blogger,, and Stumbl StumbleUp eUpon on among among them) poses new challenges to this philosophy, as the widened circle of influence among dissatisfied consumers can result in group behavior based on fewer individual experiences than ever before. As once-isolated individuals form temporary communities around specific topics of interest, they may form assumptions about the representative nature of their experience. These assumptions may involve overestimation (as can happen with any group of  5. "Diaper Rash," Patient Education Online, American American Academy of Pediatrics, 2010. 2010. http://bit.ly/AAP_DiaperRash

like-minded individuals surrounding themselves with those who share their experiences) or underestimation (as the true numbers must include many individuals who have not found the group or lack the motivation or means to participate). When the topic involves the potential harmful effects of a product, such a community quickly comes into adversarial conflict with a company that has conducted internal testing and believes their product to meet existing standards standards and (thus) to be defensibly defensibly safe. safe. As this conversatio conversation n deteriorated, with each side forced by circumstances to do its best to undermine the credibility of the other, the Consumer Product Safety Commission stepped in and promised a thorough review of Pampers' P ampers' internal documentation of the issue. We decided to pit the previous and new designs in head-to-head testing that would, regardless of the significance of specific levels of irritation caused by either diaper, offer a simple comparison of the two for consumers seeking more facts than were currently being put on the table. In so doing, we hoped to identify whether Dry Max diapers might cause more significant or longer-lasting rashes than pre-Dry Max Pampers.

Procedure Disposable diaper testing exposes adult test subjects to extreme conditions to generate magnified responses. They do this using actual urine and actual bowel movements (BM) held against the skin for periods ranging from several hours to several days. The exaggerated responses that are generated are then rated against norms using complex statistical models and dermatological assessments. We chose to mimic these procedures procedures using synthetic and actual urine as well as infant BM. Patch testing was conducted in three rounds. Since comparative results were sought, we were comfortable adjusting variables between trials to magnify overall results, provide additional comfort for the human subject, or respond to recommendations from readers. Examples of changes included reducing the size of diaper patches from a 1" strip of the full width of the diaper to a roughly 1.5" square; the elimination of dry patches after the first round of  testing, as they showed no response; and the method of preparing infant BM for testing, as described in detail below. Patches were cut from the central fill area of diapers and any open edges sealed with paper bandage tape. Diaper samples were affixed to the forearms and, in the case of dry patches, upper arms of the human subject using paper bandage tape.

In the first BM trial, small amounts of fresh infant stool were applied to patches and taped to the skin. This BM had been collected in a formerly clean pre-fold cotton diaper and stored in a plastic ziploc-style bag, but had been somewhat dehydrated by the liquid being absorbed a bsorbed by the diaper. In the second BM trial, we attempted to better "reconstitute" the relatively dry BM. To do this, we acquired a clean prefold diaper from the same provider as the BM sample; after scraping the BM diaper as clean as possible, we weighed the liquid-containing dirty pre-fold and the clean one. The difference in weight (in grams) was added back to the BM in the form of  urine. This provided the BM with a wetter texture more consistent with "fresh" BM prior to having liquid wicked away from it by a diaper. We also took the opportunity opportunity to puree the feces and urine to a smooth consistency using a disposable polypropylene plastic fork, which ensured that the BM had an even consistency with no particulates that might cause greater or lesser irritation in different samples. A measured amount (1 tsp) of this slurry was then applied to the center of the patch and taped to the subject's arm. For each trial, samples were left taped to the test subject's arms with rare disturbance for a period of eight to nine hours while the subject engaged in what limited routine activities were still available to him. All patches were then removed, the subject's arms were gently and carefully washed with a hypoallerge hypoallergenic nic soap (Dr. (Dr. Bronner's Bronner's Unscented Unscented Mild Mild Baby Soap), Soap), photograp photographs hs were taken, and rashes were comparatively assessed by an individual with no knowledge of the positioning of individual patches. Diaper Specifications All diaper types were used in every round with the exception of the single cloth diaper sample introduced in the last round of testing as an additional control. Purchase date Purchase month Location and year state or online

Scented/ Unscented blind smell test

Sample brand and style

Tracking Information code on diaper

Pre-Dry Max Cruiser

9013 9013U0 U011 1130 3015 1531 31 June June 2008 2008 Ma Mass ssac achu huse sett tts s Scen Scente ted d

Dry Max Cruiser ("A")

00864840040728 April 2010 Online

Unscented

Dry Max Cruiser ("B")

0113U017540403 May 2010 Texas

Scented

Huggies Snug (c)2009 KCWW & Dry 3E

May 2010 Texas

Unscented

Kushies all-inN/A one

January 2005 Online (estimate)

N/A

Assessing Irritation Two types of irritation were seen, which must be treated differently as they cannot be rated along a single continuum. seen immediately after removal of patches differed significantly, and in all cases was at its most pronounced after skin was gently washed with a hypoallergenic soap to remove any trace of sample materials. The presence of warm water, gentle friction, and exposure to air mimic initial steps likely taken by parents to address infant rashes, and examination of these rashes yielded several qualitative differences that could be used to classify rashes by their relative levels of irritation.

 Initial irritation

As all irritation described in this study is relative, judgments of "severity" were avoided. Thus, a "High" rash response is not intended to connote a given level of significance or harm, but simply that, relative to other rash responses, it was the highest gradation seen. The following descriptive definitions may be helpful in assessing levels of skin irritation on an individual basis. 0 = No visible rash whatsoever 1 = Low: Very slight visible rash, scattered dots to splotchy distribution 2 = Low to Moderate: Pink coloration, splotchy distribution 3 = Moderate: Pink coloration, splotchy to uniform distribution, some definition of rash edges, slightly raised areas of skin 4 = Moderate to High: Pink to red coloration, uniform distribution, defined rash edges, some raised areas of skin 5 = High: Red coloration, uniform distribution, sharply raised edges, welted appearance with swollen skin throughout Initial irritation typically subsided 90-100% within 12 hours of patch removal. Extended irritation

was in some ways less pronounced than initial irritation, but in other ways more pronounced. Descriptively, it consisted of  subtle, firm, raised bumps on the skin that could easily be felt with the fingertips and also visually identified. These bumps were not painful, and were lighter in color than the rashes that preceded them, but persisted for 24 hours or more after all initial irritation had subsided. As this distinct type of irritation was only present in rare cases, it could not easily be classified in terms of gradation; instead, we chose to log its presence or absence alone

as an indicator of rash activity, and treat it as a boost of +3 + 3 to the relative significance of a rash, as it is assumed to be an indicator of more significant skin sensitivity or vulnerability to persistent rash, recurrent rash, or eventual infection after prolonged exposure. Levels of initial irritation were assigned by a research assistant with no knowledge of sample positions for each trial. Extended irritation i rritation was noted in identical locations by multiple parties without coaching or direction.

Results Dry Patches Diaper Type

Irritation Level

PrePre-Dr Dry y Ma Max x Cru Cruis iser er 0 Dry Max Cruiser A

0

Dry Max Cruiser B

0

Hugg Huggie ies s Snu Snug g & Dry Dry 0

Wet Patches (Urine or Synthetic Urine) Diaper Type

1st Trial synthetic urine

2nd Trial human urine

Pre-Dry Max Cruiser 0

0

Dry Max Cruiser A

2

0

Dry Max Cruiser B

0

0

Huggies Snug & Dry 0

0

Soiled Patches

Diaper Type

Pre-Dry Max Cruiser

2nd 1st Trial 1st Trial Trial infant BM rash BM/urine persistence mixture 24 hours (Sample later 1, 2 if  present)

2nd Trial rash persistence 24 hours later

4

No, No

No

4, 2

Average irritation of all soiled samples

3.33

Dry Max Cruiser A

5

Yes

2, 3

Yes, No

3.33

Dry Max Cruiser B

4

No

2, 4

No, No

3.33

Huggies Snug &  Dry

4

No

1

No

2.5

Kushies Cloth Diaper

N/A

N/A

0

No

0

Average Irritation from Wet (Urine) and Soiled (BM and Urine/BM) Trials Diaper Type

Total Samples

Average

Pre-Dry Max Cruiser

5

2

Dry Max Cruiser A

5

2.4

Dry Max Cruiser B

5

2

Huggies Snug & Dry

4

1.25

Kushies Cloth Diaper 1

0

Conclusions We believe the most significant finding of our study is its demonstration that, when compared with a leading competitor or its own previous formulation, Pampers with Dry Max are more likely to t o cause extended irritation persisting long after the diaper is changed. Examining the behavior of this rash when the skin is i s repeatedly re-covered with another diaper which is then soiled or wetted on top of the persistent rash, was beyond the scope of this study; but it does not feel excessively speculative to posit that a rash so treated would be more likely to deteriorate further than skin that showed no signs of being compromised. A more troubling finding, and a highly illuminating one, is that beyond this overall  difference in performance, Dry Max Pampers from two different "batches" were associated with different levels of both initial and extended irritation. These differences were documented both by a blinded "scent test" and by their tracking codes. The batch linked to all cases of extended irritation, and which triggered the sole reaction to a urinecontaining diaper in this study, was the batch that had been acquired from a consumer whose own child had suffered from severe diaper rash while wearing diapers from the same package.

Here is a complete rundown of our conclusions from this study:

• Wet and soiled Pampers diapers with the Dry Max absorbent core caused slightly higher average levels of  initial  irritation than the previous formulation of Pampers diapers. • Dramatic differences in extended irritation were documented

at a 24-hour interval between Pampers Dry Max and the previous Pampers formulation. Specifically, extended irritation was seen with two Pampers Dry Max samples, but not with any other diaper sample by any brand in this study. • Extended irritation was documented exclusively in one of two

Pampers Dry Max sources used in this study. Patches that triggered extended irritation were taken from diapers in a package that had caused significant rash activity in a child. Diapers from this sample triggered this response in both BM trials. The fact that this same batch of Pampers with Dry Max was correlated with the sole case of irritation caused in our urine trials is both surprising and suggestive. These diapers appeared to be unscented, compared with the strong fragrance of the samples we purchased locally. • Variations in initial irritation found between Pampers and

Huggies, and between Pampers and cloth diapers, are intriguing but inconclusive. Huggies patches used the same urine and BM content, and all diapers showed reduced initial irritation with our BM/urine slurry than with BM alone. But the significantly lower result of the Huggies patch's second BM test may have been caused by the diaper's position, as it was rotated around the forearm towards the elbow. Given that this result significantly depresses the average irritation scoring of Huggies' smaller sample size, and that a single cloth diaper sample performed equally well, more testing would be needed to explore these possibilities.

Discussion What's behind the rashes? Identifying the underlying cause behind the extended irritation linked to Pampers Dry Max diapers is beyond the scope of this study. The cause could be mechanical (a more abrasive interior diaper surface, excess dessication of  the skin, or poor breathability), chemical (changes to levels of ingredients previously present, new or modified ingredients, or contaminated ingredients), or some combination of these. As mentioned above, this problem does not appear to be uniformly present in Dry Max diapers. Samples from one package regularly performed as well

as or almost as well as pre-Dry Max diapers, while the other caused extended irritation in multiple instances, in different locations on the subject, which were not linked to any other sample set. Add two facts - first, that no reaction was noted in connection with dry patch tests, and second, that the extended irritation we saw presented earlier than one would expect of an allergic response - and our data paints a highly suggestive picture of  variability in the production process, whether based on an evolving product design, regional or manufacturing-facility variations, or the challenges in mastering and refining new manufacturing processes. The possible presence of these differences offers a lens through which to view the dramatically divergent experiences reported by parents regarding Dry Max diapers, and one that is not allergy-based. Limitations of the study There were several limitations to these tests, though most were anticipated. All testing was conducted on a single adult subject, whose skin sensitivity may differ from that of infants or other adults. Eight-hour trials of urine- and fecal-loaded diaper patches were difficult to coordinate and conduct, limiting us to three rounds of testing. And some samples were positioned in unusual ways - one of our Huggies samples, for example, and our sole cloth diaper sample, were positioned on an area of the inner forearm which, in retrospect, might have decreased sensitivity. We accommodated these limitations to the best of our ability through our testing procedures and our interpretation of the results. Recommendations for follow-up testing We see several opportunities for others who might like to pursue similar or additional testing. We believe testing should be conducted at an independent third party laboratory, bringing to bear expertise in skin patch testing. Ingredients in the diapers should be professionally and chemically analyzed, and diapers should be comparatively tested in additional adult subjects (or infants, if  available) by a third party. Additionally, a comparative skin irritation test of cloth and disposable diapers, using multiple adult subjects, infant BM, and several trials, could yield interesting results.