Evaluating the Reliability of Consumer-Facing Packaging Signals for Skin Lightening Products Across Northern Manhattan
Supervised By: Dr. Llanos, Associate Professor, Department of Epidemiology Mailman School of Public Health
Project Background
The overarching research project, Project CLEAR (Chemical Exposure and Awareness Research),
is a pilot study assessing the availability and chemical composition of skin-lightening products
(SLPs) in Northern Manhattan. SLPs are widely used in communities of color and often contain
toxic chemicals such as mercury and hydroquinone, posing serious health risks. Despite
regulations, these products remain accessible through deceptive labeling and illegal sales.
Targeted marketing of SLPs in marginalized areas raises concerns about environmental
inequities and injustice as they relate to who is likely to be exposed to these products. This study
employs a novel spatial sampling approach to audit retail stores in Northern Manhattan,
assessing the availability of SLPs in relation to neighborhood context. Products are then
screened by mass spectrometry for harmful substances, including per- and polyfluoroalkyl
substances (PFAS), parabens, and heavy metals, with results compared to ingredient labels.
Conducted in four neighborhoods in Northern Manhattan (East Harlem, Central Harlem South,
Central Harlem North, and Washington Heights), this study focuses on neighborhoods with
relatively high proportions of Black and Latinx residents. Ultimately, Project CLEAR combines
spatial methods and laboratory science to map SLP availability and assess chemical risks users of
these products in Northern Manhattan might be exposed to.
Methodology
Initially, I will conduct a thorough literature review of relevant published epidemiology articles
regarding psychological consumer trends, personal care product (PCP) packaging, and the
correlation between quality and consumer-facing factors in other products. After developing an
extensive bibliography of sources, I will draft an initial introduction to set up my paper, in
addition to a concise version for my poster. Drawing from the previous papers and
methodologies I assembled in my literature review, I will then begin my data analysis. The first
step will be updating our current store dataset with the chemical screening results. Using this
complete dataset, I can begin testing associations between variables. For the price, I plan to
calculate a Pearson correlation coefficient to check for any correlation between SLP price and the
number of toxic chemicals. Then, for the country of manufacture, I will run a 2-sample test
comparing the mean number of toxic chemicals present between U.S.- and non-U.S.-
manufactured SLPs. Depending on data granularity, I will run further analyses to determine
patterns of association based on specific region or country of manufacture. Then, to check for a
correlation between containing a warning label and toxic chemicals, I plan to utilize the Chi-
square test for independence to determine whether there is any association between the
variables.
Lastly, to assess any social inequities, I will investigate whether these relationships vary by zip
code. To accomplish this, I will stratify analyses and incorporate interaction terms into
regression models to test whether the strength of these associations, or lack thereof, varies by
zip code. Then, by analyzing the relationship between the reliability of consumer-facing signals
and neighborhood-level indices (e.g., Area Deprivation Index, percentage of persons below 150%
poverty estimate, and Percentile percentage minority), I will assess whether these variances
reflect social inequities. Upon completion of my data analysis, I will write the methodology
sections accounting for the changes I make in the data analysis process. Afterwards, I will use R
and Excel to create figures for both my written paper and poster. Additionally, I will begin
drafting my conclusions and discussion based on these finalized results, along with a condensed
version for my poster. Lastly, I plan to create an infographic summarizing my main findings and
statistics regarding the accuracy of consumer-facing signals, in addition to reinforcing the
prevalence and danger of harmful chemicals in SLPs.
Objectives
Past literature has demonstrated how factors such as marketing claims, price, and country of
manufacture influence consumer decision-making around the purchase and use of SLPs.
Products that are domestically produced and those that are higher-cost often skew customer
perception about product quality and safety. SLPs are one such marketed consumer product that
customers may rely on explicitly stated claims (i.e., on the product label) while attempting to
evaluate chemical safety. Considering widely marketed SLPs continue to contain toxic chemicals
through deceptive labeling and through illegal sales of banned products, the question remains as
to whether the aforementioned consumer-facing product signals reliably indicate chemical
safety. By analyzing the chemical screening results for 30 audited SLPs against their relative
price, country of manufacturing, and marketing claims, this research project will analyze which,
if any, of these consumer-facing signals are reliable indicators of chemical safety. To address
concerns about social inequity, the likelihood and reliability of these marketing claims will be
compared across neighborhoods to determine whether vulnerable communities are more likely
to encounter misleading product safety signals.