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 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

 WASHINGTON, D.C. 20460 

OFFICE OF 

PREVENTION, PESTICIDES AND 

 TOXIC SUBSTANCES

March 16, 2011

MEMORANDUM 

SUBJECT: Ethics Review of Intentional Exposure Human Toxicity Study 

TO: Jennifer McClain 

 Antimicrobials Division 

 Office of Pesticide Programs 

FROM: Laura Parsons 

 Human Research Ethics Reviewer 

 Office of Pesticide Programs 

REF: Gulson, B., M. McCall, M. Korsch, L. Gomez, P. Casey, Y. Oytam, A. Taylor, 

M. McCulloch, J. Trotter, L. Kinsley, and G. Greenoak. (2010). Small 

Amounts of Zinc from Zinc Oxide Particles in Sunscreens Applied Outdoors Are 

Absorbed through Human Skin. Toxicological Sciences. 118(1). 140-149. 10 p. 

(MRID 48387301) 

 

I have reviewed the referenced document and have determined that all applicable 

requirements of EPA’s Rule for the Protection of Human Subjects of Research (40 CFR Part 26) 

have been satisfied. If the study is determined to be scientifically valid and relevant, I find no 

regulatory barrier to EPA’s relying on this research in its actions taken under FIFRA or §408 of 

FFDCA. 

Summary Characteristics of the Research 

The summary description of this research was obtained from the published literature and 

through email correspondence with a primary author and the Macquarie University Ethics 

Secretariat, the group which provided ethical oversight for this research. This research was 

conducted with a personal care product (sunscreen) and did not include intentional exposure to a 

pesticide. EPA is interested in this study because it concerns dermal absorption of nanoparticles 
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and therefore, if valid, this research could be used to support dermal exposure assessments for 

pesticide formulations which include nanoparticle technology. 

In this research, 20 human subjects were exposed to sunscreens containing stable 

isotopes of zinc oxides for the purpose of measuring the extent of dermal absorption of different 

sizes of zinc particles. Metal oxide nanoparticles are commonly used in sunscreens because they 

reflect and absorb ultraviolet (UV) light resulting in transparent rather than opaque coatings such 

as those found in other metal oxide sunscreens. This research was conducted in Australia in 

March 2009. 

There were 10 male and 10 female subjects ranging in age from 19 to 66 years of age. 

There were several family connections among the subjects, with three pairs of siblings and one 

father and son pair. Subjects wore UV protective upper body clothing with a patch removed to 

expose some skin on the back. Sunscreen containing stable isotope 68Zn oxide either formulated 

with “bulk” particles (110 + 46 nanometers in size) or with nanoparticles (19 + 8 nanometers in 

size) was applied twice daily for a period of 5 days to the exposed skin on the subjects’ backs. 

Thirty minutes after each of the two daily applications, the subjects were exposed to direct 

sunlight for at least 30 minutes. Participants were encouraged to wear other (nonzinc) types of 

sunscreen in the areas not covered by the UV-resistant clothing. 

Urine and blood samples were taken before first use of the sunscreen as a control for each 

individual. Urine and blood samples were taken 8 days before sunscreen application, 

immediately before the first application, at the end of each of the 5 days of application and 6 

days after the last application. Urine and blood samples were analyzed for 68Zn oxide 

concentrations. The test material was removed from each subject’s back at the end of each day 

with an alcohol-lanolin wipe. 

 The protocol was developed from a pilot study which used three subjects. While no 

ethics information was available regarding the pilot study, the pilot study was assumed to be 

conducted under the same ethics oversight as the main study, which is discussed below. 

1. Value of the Research to Society: “This paper describes the first application of stable 

isotopes in nanotechnology specifically for tracing absorption or penetration of Zn from 

ZnO nanoparticles in sunscreen applied to healthy human skin under conditions of 

normal use.” (p. 141). The study was conducted by researchers at Macquarie University 

in Sydney, Australia. The research was funded by the Commonwealth Scientific and 

Industrial Research Organization (CSIRO) and Macquarie University. This research 

addresses the question of whether nanoparticles absorb across intact skin more than 

larger particles since increased dermal absorption may have implications for many uses 

of nanotechnology including use in personal care products as well as in pesticidal uses. 

 

2. Subject Selection: Twenty-two adult males and females were recruited through 

“personal contacts” of the researchers. (see email correspondence as Attachment 1). 

Two subjects withdrew before the monitoring began, leaving 20 subjects for the study. 

Seventeen subjects completed all the monitoring while three subjects completed part, but 
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not all, of the study. The ages ranged from 19 to 66 years of age. The researcher 

reported that none of the female subjects were pregnant. (see email correspondence as 

Attachment 1). There is nothing to suggest that the subject selection was in any way 

coercive or inequitable. 

2. Risks and Benefits: The main risks were in blood sampling and any adverse reaction to 

the sunscreen formulations. The sunscreen formulations contained an enriched level of a 

stable isotope of zinc which does not pose a higher risk than naturally occurring zinc and 

“many” commercially available sunscreens contain “nanoparticulate TiO2 and/or ZnO”. 

(p 140). Risks were minimized by using a trained phlebotomist to collect blood samples, 

and questioning potential subjects regarding “adverse reactions to cosmetics”. Rules for 

managing risks were not specifically discussed in the study, but they are discussed in the 

National Statement on Ethical Conduct in Human Research (Supplement 1, p 17) and the 

exposure was suspended early for one female subject who had an adverse reaction to the 

sunscreen. 

There were no benefits to subjects. The risk-benefit balance was not discussed in the 

study report. But given that the risks were small, the potential benefits to society 

outweigh the risks. 

3. Independent Ethics Review: This research was reviewed and approved by the 

Macquarie University Human Research Ethics Committee which is an Australian 

National Health and Medical Research Council (NH&MRC) registered ethics committee. 

This research was reviewed under the National Statement on Ethical Conduct in Human 

Research.

4. Informed Consent: The subjects attended a meeting at the researcher’s house one week 

before the study during which the study procedures and risks were described. The 

researchers stressed the need for their commitment for the five days of exposure and the 

several days of follow up. Brian Gulson, Ph.D., the principal author of this publication, 

confirmed that each of the subjects provided written consent (see email correspondence 

as Attachment 1); however, no further information on the consent process was available. 

 

6. Respect for Potential and Enrolled Subjects: No mention was made of whether or not 

subjects were free to withdraw without penalty, but two subjects did withdraw early in 

the study. The subjects were provided with a unique identifier and only the researchers 

directly involved had access to these and the data. The publication did not include any 

information about compensation for subjects. 

Applicable Standards 

 

This research was conducted in Australia in March 2009, after EPA’s amended Rule for 

the Protection of Human Subjects of Research became effective on April 7, 2006. 
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Standards Applicable to the Conduct of the Research 

FIFRA §12(a)(2)(P) does not apply to this research because it did not involve the use of a 

pesticide. The portions of EPA’s regulations regarding the conduct of research with human 

subjects, 40 CFR part 26 subpart A - L, do not apply since the research neither was conducted or 

supported by EPA nor was it conducted by a person with the intention to submit the results to 

EPA. 

The international standards for this type of research are provided in the 2004 Helsinki 

Declaration. 

The Australian Government Standards Governing Research with Human Subjects, which 

were applicable when this research was initiated, are provided in the National Statement on 

Ethical Conduct in Human Research. An excerpt of this statement is provided as Supplement 1.

The full text of the statement can be found at: 

http://www.nhmrc.gov.au/publications/synopses/e72syn.htm 

Standards Applicable to the Documentation of the Research

 EPA identified this study through a review of the public literature. No person has 

independently submitted the published article or any results of this research to EPA. 

Consequently, the requirements for the submission of information concerning the ethical conduct 

of completed human research contained in EPA regulations at 40 CFR part 26, subpart M do not 

apply. 

Standards Applicable to EPA’s Reliance on the Research 

The Agency’s rule (40 CFR part 26 subpart Q) defines standards for EPA to apply in 

deciding whether to rely on research—like this study—involving intentional exposure of human 

subjects. The applicable acceptance standards from 40 CFR part 26 subpart Q are these: 

§26.1703. Prohibition of reliance on research involving intentional exposure of 

human subjects who are pregnant women (and therefore their fetuses), nursing 

women, or children. Except as provided in §26.1706, in actions within the scope of 

§26.1701 EPA shall not rely on data from any research involving intentional exposure of 

any human subject who is a pregnant woman (and therefore her fetus), a nursing woman, 

or a child. 

§26.1705 Prohibition of reliance on unethical human research with non-pregnant, 

non-nursing adults conducted after April 7, 2006. Except as provided in §26.1706, in 

actions within the scope of §26.1701, EPA shall not rely on data from any research 

initiated after April 7, 2006, unless EPA has adequate information to determine that the 

research was conducted in substantial compliance with subparts A through L of this part, 

or if conducted in a foreign country, under procedures at least as protective as those in 
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subparts A through L of this part. This prohibition is in addition to the prohibition in 

§26.1703. 

Compliance with Applicable Standards 

This research did not involve intentional exposure of any pregnant or nursing female 

subjects or any children. Reliance on the research is therefore not prohibited by 40 CFR 

§26.1703. 

EPA is forbidden by 40 CFR §26.1705 to rely on data from research involving intentional 

exposure—such as this study— “unless EPA has adequate information to determine that the 

research was conducted in substantial compliance with subparts A through L of this part, or if 

conducted in a foreign country, under procedures at least as protective as those in subparts A 

through L of this part.” This research was approved by the Macquarie University Human 

Research Ethics Committee, formerly the Macquarie University Ethics Review Committee 

(Human Research), which is a National Health and Medical Research Council (NH&MRC) 

registered ethics committee. Any research that is reviewed and approved by this committee must 

meet the requirements of the National Statement on Ethical Conduct in Human Research

(Supplement 1). These requirements are similar to the requirements of 40 CFR §26 subparts A 

through L in terms of risk minimization, informed consent, respect for subjects and the 

requirements of independent ethics review. Further, the authors of the publication certified that 

“all research involving human subjects was done under full compliance with all government 

policies and the Helsinki Declaration.” (p 140). Copies of the approval letters, email 

correspondence, and statements in the publication provide enough information to conclude that 

the research substantially complied with requirements of a foreign procedures that were as 

protective as those in 40 CFR §26 subparts A through L. Therefore, reliance on this research is 

not prohibited by 40 CFR §26.1705. 

Conclusion 

I find no barrier in law or regulation to reliance on MRID 48387301 in EPA actions taken 

under FIFRA or §408 of FFDCA. I defer to others for a full review of the scientific validity of 

this study. If it were determined not to have scientific validity, it would also not be ethically 

acceptable. 
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Attachment 1: Email Correspondence 

Date 

(2011) 

Email From Email To Contents Page 

 

Jan 3 Laura Parsons Dr. Gulson Request for information 7 of 16 

Jan 3 Dr. Gulson Laura Parsons Response to request 9 of 16 

Jan 12 Dr. Gulson Laura Parsons Links to National Ethics Statement 

and Answers to EPA Questions 

10 of 16 

Jan 31 Laura Parsons Gulson and Thorp Request for statement from Ethics 

Secretariat 

12 of 16 

Jan 31 Fran Thorp Laura Parsons Information from Macquarie 

University Ethics Officer 

13 of 16 

Feb 17 Laura Parsons Gulson and Thorp Request for approval letters 14 of 16 

Feb 27 Dr Gulson Laura Parsons Copies of approval letters from May 

and December 2006. 

16 of 16 
Page 7 of 16 

From: Laura Parsons/DC/USEPA/US 

To: bgulson@gse.mq.edu.au 

Cc: Kelly Sherman/DC/USEPA/US@EPA, William Jordan/DC/USEPA/US@EPA 

Date: 01/03/2011 04:58 PM 

Subject: Request for further information on conduct of study "Small Amounts of Zn from ZnO Particles...." published 

in Toxicological Sciences. 

Dear Dr. Gulson, 

I am a US Environmental Protection Agency staff member in the Office of Pesticide Programs working on 

ethics issues for pesticide research with human subjects. The Pesticide Office has a specific regulation 

(40 CFR part 26) governing our use of research with human subjects which went into effect in April 2006. 

One of our risk assessors has reviewed your recent paper in Toxicological Sciences and believes that 

your research would be instructive in EPA's assessment of other uses of nano-technology. She has 

asked my group to review your paper for compliance with EPA's ethics regulations since our regulation 

requires EPA and our advisory board to review the ethical conduct of this study if we decide to use it to 

inform our assessments. We do not mean to imply that we believe that your research was in any way 

unethical. 

I note that your publication indicates that the research was conducted in compliance with all government 

policies and the Helsinki Declaration and was approved by human ethics committees at Macquarie 

University and Commonwealth Scientific and Industrial Research Organization (CSIRO). I have 

skimmed Australia's National Statement on Ethical Conduct in Human Research (2007), and while I am 

not completely clear what guidance covers your particular research method or field, it is clear that our 

government guidelines are similar. 

I am writing to you to request the records of the approvals of your research by Macquarie and CSIRO so 

that we can conduct our own ethics review as required by our regulation. In addition we are interested in 

other records or information you could provide regarding: 

• How were your subjects recruited and selected? 

• Were any of the female subjects pregnant or nursing? 

• What risks to subjects were identified and how they were minimized? 

• How were risks to subjects weighed against the benefits for the subjects and society? 

• Informed consent. What were your subjects told about the research and did they give written 

consent? Can we see a copy of the consent form? 

• How was the privacy of individuals protected? 

It is our plan to review your research for scientific and ethical conduct and to present those reviews to our 

Human Studies Review Board (HSRB) as required for our use of your research in our pesticide risk 

assessments. I would be glad to answer any questions that you have about this process. Below I have 

copied the pertinent section governing EPA's use of human research from our Code of Federal Regulation 

Part 26. Also, here is a link to the HSRB website: http://www.epa.gov/osa/hsrb/ 

I look forward to working with you. 

Thank you, 

Laura Parsons 

Office of Pesticide Programs 
Page 8 of 16 

703-305-5776 

§ 26.1602 EPA review of completed human 

research. 

(a) When considering data under 

FIFRA or FFDCA from research 

involving intentional exposure of 

humans, EPA shall review the material 

submitted under § 26.1303 and other 

available, relevant information and 

document its conclusions regarding the 

scientific and ethical conduct of the 

research. 

(b) EPA shall submit its review of data 

from human research covered by 

subpart Q, together with the available 

supporting materials, to the Human 

Studies Review Board if EPA decides to 

rely on the data and: 

(1) The data are derived from research 

initiated after April 7, 2006, or 

(2) The data are derived from research 

initiated before April 7, 2006, and the 

research was conducted for the purpose 

of identifying or measuring a toxic 

effect. 

(c) In its discretion, EPA may submit 

data from research not covered by 

paragraph (b) of this section to the 

Human Studies Review Board for their 

review. 

(d) EPA shall notify the submitter of 

the research of the results of the EPA 

and Human Studies Review Board 

reviews. 

§ 26.1603 Operation of the Human Studies 

Review Board. 

EPA shall establish and operate a 

Human Studies Review Board as 

follows: 

(a) Membership. The Human Studies 

Review Board shall consist of members 

who are not employed by EPA, who 

meet the ethics and other requirements 

for special government employees, and 

who have expertise in fields appropriate 

for the scientific and ethical review of 

human research, including research 

ethics, biostatistics, and human 

toxicology. 

(b) Responsibilities. The Human 

Studies Review Board shall comment on 

the scientific and ethical aspects of 

research proposals and reports of 

completed research with human 

subjects submitted by EPA for its review 

and, on request, advise EPA on ways to 

strengthen its programs for protection of 

human subjects of research. 
Page 9 of 16 

 From: Brian Gulson <brian.gulson@mq.edu.au> 

 To: Laura Parsons/DC/USEPA/US@EPA 

 Cc: Maxine.Mccall@csiro.au, Ethics Secretariat < 

 ethics.secretariat@mq.edu.au> 

 Date: 01/03/2011 06:06 PM 

 Subject: Re: Request for further information on conduct of study 

 "Small Amounts of Zn from ZnO Particles...." 

 published in Toxicological Sciences. 

 Dear Laura, 

 Thank you for your interest in our research. I am retired 

 (supposedly) and don't often go into the University anymore. I wll forward your 

 request to our ethics people and look at your additional questions. 

 Kind regards 

 Brian Gulson 
Page 10 of 16 

 From: Brian Gulson <brian.gulson@mq.edu.au> 

 To: Laura Parsons/DC/USEPA/US@EPA 

 Cc: Ethics Secretariat <ethics.secretariat@mq.edu.au> 

 Date: 01/12/2011 07:02 PM 

 Subject: Re: Request for further information on conduct of 

 study 

 "Small Amounts of Zn from ZnO Particles...." published in 

 Toxicological Sciences. 

 Dear Laura 

 I spoke with the ethics office at the University yesterday and they 

 provided me with the links that cover ethics in the Uni as listed 

 below. 

 A request to see the records of approval is highly unusual and as it 

 is confidential do not provide such information to outside parties. 

 I cannot speak for CSIRO and have not heard from them. 

 "Hi Brian 

 thank you for your call earlier. Here are the links to the National 

 Statement on Ethical Conduct in Human Research (2007) and the 

 Australian Code for the Responsible Conduct of Research (2007). These 

 are the national documents informing ethical review in Australia. 

http://www.nhmrc.gov.au/publications/synopses/e72syn.htm

http://www.nhmrc.gov.au/publications/synopses/r39syn.htm

 Cheers 

 Nicola" 

 With respect to the other questions: 

 How were your subjects recruited and selected?

 #As in any human study (or that I have run), recruitment is a major 

 issue. In this case we advertised by email within the University and 

 CSIRO, and gave a presentation at the Surf Life Saving Club but 

 received no response. We then used personal contacts to obtain the required 

 numbers. 
Page 11 of 16 

 Were any of the female subjects pregnant or nursing?

 #No 

 What risks to subjects were identified and how they were minimized?

 #The main risks were in blood sampling and any adverse reaction to the 

 sunscreen formulations. The blood samples were taken by a trained 

 phlebotomist. Re sunscreen: the volunteers were asked in the 

 questionaire and personally if they if they suffered adverse reactions 

 to cosmetics. None replied in the positive at that time. 

 How were risks to subjects weighed against the benefits for the

 subjects and society?

 # As the risks were considered to be minimal, the potential benefits 

 to society far outweighed the risks. 

 Informed consent. What were your subjects told about the research

 and did they give written consent?

 #The subjects attended a meeting at my house 1 week before the trial 

 started and I described the trial and any risks. I also stressed the 

 need for their committtment for the 5 days and follow up, and for 

 minimal contamination of samples during collection (this applied 

 especially to urine samples as we did not accompany the subjects into 

 the toilets). 

 One subject withdrew on the evening as they did not wish to provide 

 blood samples for the duration and one had study committments and 

 withdrew on the first day of the trial. 

 Each morning at the beach I reiterated the messages. 

 Can we see a copy of the consent form?

 ##This is up to the University ethics secretariat. 

 How was the privacy of individuals protected?

 #The subjects were provided with a unique identifier and only the 

 researchers directly involved had access to these and the data. 

 I hope this is sufficient and please contact me if you require further 

 assistance. 

 Kind regards 

 Brian 

 
Page 12 of 16 

From: Laura Parsons/DC/USEPA/US 

To: Brian Gulson <brian.gulson@mq.edu.au>, Ethics Secretariat <ethics.secretariat@mq.edu.au> 

Cc: Kelly Sherman/DC/USEPA/US@EPA, William Jordan/DC/USEPA/US@EPA 

Date: 01/31/2011 03:18 PM 

Subject: Re: Request for further information on conduct of study "Small Amounts of Zn from ZnO Particles...." 

published in Toxicological Sciences. 

Brian and Nicola: 

Thank you for this information and the links. I had skimmed the information contained in the links as I 

was looking at the summary of your research before contacting you. We certainly do not intend to 

request any information that would be considered confidential. 

Would the Ethics Secretariat provide a statement that, in their view, your research complied with the 

applicable provisions of the Australian ethics rules? In that case, my presentation to our Human Studies 

Review Board would be a cross-walk between your (Australian) ethics rules and our regulation. 

I very much appreciate your time and effort on this. Please let me know if a statement from the Secretariat 

is possible and if I need to pose this request to someone other than Nicola. 

Thank you, 

Laura 

. 

Laura Parsons 

Office of Pesticide Programs 

703-305-5776 
Page 13 of 16 

From: Ethics Secretariat <ethics.secretariat@mq.edu.au> 

To: Laura Parsons/DC/USEPA/US@EPA 

Cc: Brian Gulson <brian.gulson@mq.edu.au>, Kelly 

 Sherman/DC/USEPA/US@EPA, William Jordan/DC/USEPA/US@EPA, 

 Kandy White <karolyn.white@mq.edu.au> 

Date: 01/31/2011 08:42 PM 

Subject: Re: Request for further information on conduct of study 

 "Small Amounts of Zn from ZnO Particles...." published in 

 Toxicological Sciences. 

Sent by: fran.thorp@mq.edu.au

Dear Laura 

Thank you for your email. 

I have copied this email to Dr Karolyn White, the Director of Research 

Ethics at Macquarie University who may wish to add to the information I 

have provided below. 

The Macquarie University Human Research Ethics Committee, formerly the 

Macquarie University Ethics Review Committee (Human Research), is a 

National Health and Medical Research Council (NH&MRC) registered ethics 

committee and any research that is reviewed and approved by this 

committee must meet the requirements of the National Statement on 

Ethical Conduct in Human Research (NHMRC 2007). In the year Brian's 

research was initially considered the relevant document was the National 

Statement on Ethical Conduct in Research in Research Involving Humans 

(NH&MRC 1999) which was replaced by the National Statement on Ethical 

Conduct in Human Research in 2007. 

Please see the NH&MRC weblink link to information about the Human 

research Ethics Committees in Australia. 

http://www.nhmrc.gov.au/health_ethics/hrecs/overview.htm

The letter of Final Approval that Brian was given for the research to 

proceed is the usual document researchers use to show that the research 

has been through the appropriate ethics review process in Australia and 

that the research meets the requirements of the National Statement. Any 

amendments made to the project since the final approval was issued were 

reviewed and approved under the same framework, i.e. they met the 
Page 14 of 16 

requirements of the National Statement. 

Brian will be able to supply you with a copy of the final approval 

letter and relevant amendment approval correspondence if this would be 

helpful. If you feel an additional document or statement that the 

research complied with Australian ethics standards is required, please 

contact Dr White who will be able to assist you. 

Please do not hesitate to contact the Ethics Secretariat if we can be of 

further assistance. 

Regards 

Fran 

Ms Fran Thorp 

Human Research Ethics Officer 
Page 15 of 16 

From: Laura Parsons/DC/USEPA/US 

To: Brian Gulson <brian.gulson@mq.edu.au> 

Cc: fran.thorp@mq.edu.au, Kandy White <karolyn.white@mq.edu.au>, Kelly Sherman/DC/USEPA/US@EPA, 

William Jordan/DC/USEPA/US@EPA, Ethics Secretariat <ethics.secretariat@mq.edu.au> 

Date: 02/17/2011 10:22 AM 

Subject: Re: Request for further information on conduct of study "Small Amounts of Zn from ZnO Particles...." 

published in Toxicological Sciences. 

Hi Brian, 

This note below from Ms. Thorp was very helpful. Would it be possible for you to send the copy of the 

Letter of Final Approval that she mentions to show that your research went through the ethics process in 

Australia? 

I can probably use our email exchanges if necessary, but a copy of your approval letter would be a neater 

package. 

Thank you, 

Laura 

 

Laura Parsons 

Office of Pesticide Programs 

703-305-5776 

From: Brian Gulson <brian.gulson@mq.edu.au> 

To: Laura Parsons/DC/USEPA/US@EPA 

Date: 02/17/2011 08:28 PM 

Subject: Re: Request for further information on conduct of study "Small Amounts of Zn from ZnO Particles...." 

published in Toxicological Sciences. 

Hi Laura 

 

I am out of town until the end of next week but will try and track this down (came as hardcopy) 

when I return and email a copy to you. 

 

Kind regards 

Brian 
Page 16 of 16 

From: Brian Gulson <brian.gulson@mq.edu.au> 

To: Laura Parsons/DC/USEPA/US@EPA 

Date: 02/27/2011 06:55 PM 

Subject: Re: thank you 

Hi Laura 

Attached are some notes from the ethics committee. 

The original application was in my PhD students name (Herbert Wong) who later withdrew from 

his candidature because of medical reasons. 

Hope this is useful. 

Brian