In
October 2015 a group of scientists from the U.S. and Israel published
a paper in the journal, Archives of Environmental Contamination and
Toxicology entitled: Toxicopathological effects of the sunscreen UV
filter, Oxybenzone (Benophenone – 3), on coral planulae and
cultured primary cells and its environmental contamination in Hawaii
and the U.S. Virgin Islands. Not exactly a catchy title is it? Yet
this scientific paper with its exact and very dull title has sparked
global headlines that put the blame for the destruction of the
world's coral reefs firmly at the door of sunscreens and by
implication the swimmers, snorkellers, divers and tourists who use
it.
We
were going to show you the full abstract from the paper but it is
long, full of hard words and we really didn't have the time or
inclination. So here's a quick summary. Certain sunscreens contain
the active ingredient Oxybenzone which, the paper points out, has
been found to have a destructive effect on coral DNA leading to coral
bleaching and the ossification of coral planulae – juvenile coral
literally become encased in their own skeleton and die.
This
isn't the first time that such a link has been made between coral
destruction and sunscreens either. Back in 2008, another group of
scientists, this time from Italy, published a paper in the journal of
Environmental Health Perspectives entitled: Sunscreens cause coral
bleaching by promoting viral infections. Now, you have to admit,
there is no ambiguity in that title. No wishy-washy use of the term
“effects”. The Italians were adamant, sunscreens cause coral
bleaching. The Italian experiments showed that sunscreens cause rapid
and complete bleaching of hard coral. The effects of sunscreens is
due to organic ultraviolet filters, which are able to induce the
lytic viral cycle in symbiotic Zooxanthellae with latent infections.
Nope, we don't now what that means either but the Italians concluded
it wasn't very good. And that with increasing tourism to some of
the worlds most precious marine environments and the associated use
of sunscreen in those environments, things were going to get worse.
However they did not single out Oxybenzone in particular, rather they
found sunscreens containing parabens, cinnamates and camphor
derivatives as well as Oxybenzone contributed to coral bleaching even
at low concentrations.
Things
then, don't look good for the manufacturers of sunscreens or the
doctors who demand that we smear the stuff all over ourselves even on
cloudy days (see, Tell Doctor Doom To Get A Life). Nor do things look
that rosy for all the global warming fanatics either. After all if
it's sunscreen smothered tourists that are destroying the reefs and
not global warming – sorry climate change- then a lot of scientists
are going to end up stacking shelves down the local supermarket.
Another conspiracy perhaps?
But
before you you go out and buy some non-chemical, dolphin friendly,
coral reef loving sun lotion made from papaya juice and hippy spit
from your local organic shop, let's sit back and think about this for
a minute. These are scientific papers and as such they conform to the
scientific notion of “put up or shut up”. In other words, these
scientists have done their experiments, examined the results,
hypothesised, formed their conclusions and published their work to
all and sundry. Then they have sat back and waited for their results
to be examined and either confirmed or criticised. Granted the
Italians could be accused of having been a bit unwise by being so
adamant - which in scientific terms is a little like walking around a
fireworks factory with a naked flame, sooner or later something will
blow up in your face – but nevertheless they have published and
waited for the response, not from journalists who are just after a
good headline, but academics. And the response has been... Well....
not all that great really.
A
number of scientists and experts have cast doubt on the studies.
Responding to the 2015 study, Terry Hughes, Director of the
Australian Research Council of Excellence for Coral Reef Studies at
James Cook University (wow what a title) thought the paper's findings
were inconclusive.
“This
particular study was done in a laboratory, so they actually used
artificial sea water,” Hughes explained. “They put tiny bits of
coral into aquaria and then added some chemicals. It's not surprising
that corals don't like chemicals thrown at them.”
Hughes
went on to say that the media's extrapolations that sunscreen is
threatening the worlds coral “are a bit of a stretch”. “The
conclusion from the media is sunscreen is killing the worlds coral,
and that's laughable. The biggest stresses are climate change,
overfishing and pollution, and pollution more generally than
sunscreen.”
Hughes
explained further that: “Sunscreen, because of its source is far
less of a problem than run-off of pesticides from rivers.” The
study claims that at least 10% of global reefs are at risk of
exposure. “Many reefs are remote, without tourists and many of
them are nonetheless showing impact from climate change... If you
want to study global threats you have look on a global scale and they
haven't done this.” Hughes said.
Mike
Van Keulen, Director of Coral Bay Research Station at Murdoch
University thought that laboratory studies were going to be limited
in their scope but that the 2015 study did provide some concerning
information about the toxicity of compounds contained in sunscreen.
“If we start adding all these little things, sunscreen but also
sewage, overfishing... They will altogether reduce the resilience of
coral reefs.”
Craig
Downs, one of the lead authors of the 2015 study said: “Whatever
island/reef system that is populated and sees intense visitation (by
tourists) you have sunscreen usage and hence contamination.” Downs
however, agreed that it is not just swimmers that are the problem but
also sewage. “My professional opinion,” Downs said, “is that
agricultural run-off and sewage... are probably responsible for the
historical collapse of coral reefs for the past 40 years.” Err...
Okay, so why study sunscreens then?
Writing
on the Dermal Institute website Dr Diana Howard offered up some
rather cutting criticism of the 2008 study. Citing the lead author of
the Italian study Dr Howard wrote: Dr.
Robert Danovaro at the Polytechnic University of the Marche in
Anacona, Italy (Environmental Health Perspective vol 116, April 2008)
published a study that stated, "4-6,000 metric tons of sunscreen
wash off swimmers per year globally." He calculated that "10%
of coral reefs are in danger" and stated "chemical
sunscreens should be avoided in favor (sic) of physical sunscreens."
He did however note that, "sunscreens are not the only factor
behind declining reefs". As you might expect the media chose to
overlook this latter point and instead scare the public into not
wearing sunscreens. Likewise, some clever marketers decided to brand
coral reef safe sunscreens which use zinc oxide and titanium dioxide
instead of chemical sunscreens. Of course it would only be a matter
of time before someone complained that these physical sunscreens were
not biodegradable and also detrimental for the earth.
Dr
Howard then when on to cite a plethora of other experts who took
umbrage with the study including the aforementioned Terry Hughes, he
of the very impressive title. “Any contaminant can experimentally
damage a coral under artificially high concentrations. The amount [in
the wild] must be tiny due to dilution," Hughes said. "Imagine
how much water a tourist wearing one teaspoon of sunscreen swims
through in an hour-long snorkel. Compared to real threats like global
warming, run-off and overfishing, any impact of sunscreen is unproven
and undoubtedly trivial.”
Prof.
Hoegh-Goldberg, Biological & Chemical Sciences at University
Queensland stated: "This study is stretching the findings and
conclusions to ridiculous extremes." In addition, Durwood
Dugger, University of Florida, and founder of Biocepts Aquaculture
commented that, "the authors conclusions are neither valid nor
supported scientifically; you must consider the dilution factor in
the ocean. There is no sampling of ocean waters around reefs to
determine if sunscreens are even present and no one has ever detected
sunscreens in the ocean. Furthermore, they have not excluded other
environmental contributing factors. It is an accepted fact that during the past 20 years, coral bleaching has increased
dramatically. Some possible causes include temperature change, excess
UV radiation, pollution, bacterial pathogens, pesticides,
hydrocarbons, other contaminants."
Professor
Hoegh-Goldberg went on to point out that the study is interesting,
but notes that many factors are likely to be responsible. "Bleaching
is like a runny nose: there are lots of things that could cause it.
Climate related bleaching is a direct consequence of heat stress and
does not involve viruses or bacteria."
Dr
Howard concluded her piece by writing: As
you can see the claim that sunscreens are destroying our coral reefs
is not well supported by many authorities in the scientific world and
it would be premature and quite frankly dangerous for individuals to
STOP wearing sunscreen while at the beach or swimming until such time
that this claim can be fully supported with scientific facts.
Unfortunately, many journals and papers have reignited interest in
this story as we enter into summer season and we are already getting
questions from consumers about the safety of sunscreens and the coral
reefs. It is my expert opinion, as well as that of many other
scientists around the world, that until additional studies are done
to confirm or substantiate the 2008 study there should be no concern
that sunscreens are harming the environment. So go to the beach, have
a great time and wear your sunscreen!
So
as far as we can see the jury is out on the subject, not that you'd
notice from all the media coverage that seems more adamant than the
Italians. A quick scan of the web and you'll be confronted with news
stories and opinions that all use dramatic and unambiguous language.
Sunscreens “are” destroying coral reefs. Sunscreens “damage”
coral reefs or that we are all (meaning tourists) “directly
contributing” to coral reef destruction. Yet the evidence doesn't
actually support these unequivocal headlines.Then there are the
“safe-sunscreen” manufacturers who've spotted a an opportunity
and, luckily, have a ready supply of coral safe sunscreens ready to
deliver to you door in exchange for a hand full of bucks. And there
are the environmental bloggers/activists demanding the banning of
everything from Oxybenzone to tourism, even the diving organisation
PADI has a web-page offering advice on “safe sunscreens” for
divers. Most of you will know that we don't think much of PADI in the
first place and the fact that they offer advice on sunscreen doesn't
help them in our minds, in fact they've gone down even further in our
estimations. The fact is that we have read the studies and although
we are not scientists, we can still find some glaring flaws. For one
thing there are only two studies in total on the subject. Yep that's
right only two. We'll say that again, just to be adamant about it, There are only two studies! And neither actually agree on the effect
of sunscreens on coral. The Italians believe that sunscreens effect
coral by promoting viral infections.
The 2015 study, on the other
hand says it is down to sunscreens causing DNA damage. So that's two
research papers using similar methodologies that have come up with
two very different conclusions and both have come in for some heavy
criticism in regard to their methodology, extrapolation of results,
failure to take into consideration other environmental factors and
their conclusions. In short, they've put up and been told to shut up.
You could always argue that those
who pour scorn on the research would say that wouldn't they? After
all, as we pointed out earlier, they don't want to end up packing
bags in a supermarket when their own research gets lampooned. Yet
even Mulder and Scully would have difficulty coming up with a
scientific conspiracy based on these two, very small studies. Both
studies took coral, placed them into aquaria or in the case of the
Italians, put them into bags and added chemicals... Following that
sort of methodology, we reckon that if you took some coral, put it
into bag with seawater, urinated in it and then waited a few weeks,
you'd end up with a bag of dead coral floating in some very smelly
fluid. We could then conclude that human urine kills coral and demand
that everyone is prevented from peeing in the ocean. In fact let's
stop everyone, everywhere from peeing at all – you can't be too
careful with environmental contaminants can you?
Anyway,
what to do. Well we'd never tell anyone what to do, we only tell you
what we will do which is this; when we go snorkelling in the summer
we will be going out in the sun because we don't want to die from
vitamin D deficiency and we will be wearing sunscreen because we
don't want our heads to turn into giant mutant freckles. What you do
is up to you but we would point out one thing, the science regarding
sunscreens destroying coral is, as many experts point out,
interesting but very limited and inconclusive. The science around
skin cancer however, is rather more convincing and there is helluva
lot more of it.
Oh
by the way, despite what a great many people seem to think, the
American Institute of Dermatology points out that there is no
evidence to suggest that Oxybenzone is harmful to humans in anyway
and is one of the only compounds that effectively protects against UVA and
UVB. Zinc Oxide and Titanium Dioxide on the other hand, despite been
lauded by many as safer alternatives to chemicals such as Oxybenzone,
are non-biodegradable and are damaging to a variety of marine life –
so we won't be believing all that marketing garbage either.
Further
reading
2008 research full paper (good luck with that)
And
if you interested here's a science paper on the possible hormonal
effects of sunscreens on humans – Mulder get Scully there's a
conspiracy to look at!
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