Sunscreen Chemicals Found In Human Samples
As reported by ScienceDaily (11/10) Exposure of Humans to Cosmetic UV Filters Is Widespread, Study Finds
An investigation conducted in the context of the Swiss National Research
Programme (NRP50), Endocrine Disrupters: Relevance to Humans, Animals and
Ecosystems, demonstrates for the first time that internal exposure of humans to
cosmetic UV filters (sunscreen chemicals) is widespread.
In the course of the Summer and Fall 2004, 2005 and 2006 (3 cohorts), human milk
was sampled by mothers who had given birth at the University Women's Hospital
in Basel. The participants filled out a detailed questionnaire with general
questions and, as special feature, in depth questions on use of different types
of cosmetic products.
Chemicals out of a large range of products including "modern" chemicals and
classical persistent organic pollutants (POPs) were analyzed in the same human
milk sample by analytical laboratories in Freiburg, Erlangen and Baden. The
list comprised cosmetic UV filters, synthetic musk fragrances, pesticides,
phthalates, parabens, flame retardants (polybrominated diphenylethers), and
polychlorinated biphenyls (PCBs); in total 89 analyses per milk sample. The
chemical analytical data of milk samples of individual mothers were then
compared with the information obtained through the questionnaire.
The investigation revealed that one and the same human milk sample contained a
large range of chemical contaminants, most of which are known to interact with
endocrine systems. Individual exposure patterns differed between different
types of chemicals. The study demonstrates for the first time that internal
exposure of humans to cosmetic UV filters is widespread. Cosmetic UV filters
were present in 85% of human milk samples, at concentrations comparable to
PCBs. Synthetic musk fragrances were also present in the milk samples. The
presence of UV filters in human milk was significantly correlated with the use
of cosmetic products containing these UV filters. As a result, exposure
patterns differed between individuals.
It seems plausible that exposure to other cosmetic constituents such as
synthetic fragrances is also linked to the use of the corresponding products.
However, this could not be investigated because musk fragrances are not
declared. In contrast, classical contaminants such as PCBs, DDT and metabolites
of DDT as well as some other persistent organochlor pesticides represented a
rather uniform background exposure. Their levels were in part correlated with
each other and also with fat-rich nutrition.
A total daily intake of each individual chemical was calculated for each
individual infant from their individual levels in human milk. Calculation
included fat content of individual milk samples, total daily milk intake per
infant and body weight of the infant. Some infants exhibited values of daily
intake of PCBs and several organochlor pesticides that were above US EPA
reference dose values.
Margret Schlumpf and Walter Lichtensteiger, who lead the research said,
"Research on the effects of endocrine disrupters (chemicals interfering with
hormone actions) has shown that it is of utmost importance to obtain
information on simultaneous exposure of humans to different types of chemicals
because endocrine active chemicals can act in concert. Information on exposure
is particularly important for the developing organism at its most sensitive
early life stages. Human milk was chosen because it provides direct information
on exposure of the suckling infant and indirect information on exposure of the
mother during pregnancy."
An important question during the research was: To what extent lifestyle can
influence the presence of chemicals in breast milk? This question was the
foundation for the preparation of the questionnaire. The questions were focused
particularly on the use of cosmetic products; information on the relationship
between the exposure of human populations to constituents of cosmetics and the
presence of these constituents in the human body was limited and, in the case
of UV filters, absent.
Gert-Jan Geraeds, Executive Publisher of Chemosphere commented, "This study once
again emphasizes the importance of global research on the impact of
contaminants in the human environment and the need for continuous critical
assessment of our priorities in environmental health and consumer habits. I am
sure that this investigation will also spark debate at the upcoming first
Environmental Health conference in Brazil, February 2011."
The three year study involved toxicologists from GREENTOX and collaboration from
personnel of the University of Zürich, University Women's Hospital Basel, University in Lausanne, and analytical
chemists from Freiburg, Erlangen (Germany) and from Baden bei Wien (Austria).