Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 20-02-2009, 09:57   #31
Registered User
 
sailorgal's Avatar

Join Date: Feb 2005
Location: Panhandle Florida
Boat: 48' Hi Star
Posts: 211
Images: 3
Quote:
Originally Posted by stevensc View Post
Rub it on your face and skin no problem, at 10 parts per million it poisons coral reefs!!!!??
If anyone would like a doctorate let me know, I have some friends in Colombia who know people that for $500.00 will print one out in a jiffy (take you pick of university and field), complete with "cheat sheets"; who your professors were and what went on at the university during your "studies" there so you don't get caught up in a lie during an interview.
Steve

Okay, I'll bite. What is your scientific background and training? Are you sure there is no problem when you rub that stuff on your skin. Don't you think some of it is absorbed into your system? Could it be that for humans the benefits outweigh any risks. Not saying there are risks, I don't know. Also, a human being is quite different than a coral polyp in physiology, etc.

The causes of coral reef bleaching and death are currently being studied by many scientists, and as I pointed out in my first post to this thread, there are multiple suspected causes. I'm currently doing research on some of the gene expression changes to corals acclimated to high and low UV levels. I'll keep you all posted on the results when I finish.
__________________

__________________
How can I get lost?? I don't know where I'm going!
sailorgal is offline   Reply With Quote
Old 20-02-2009, 10:06   #32
Senior Cruiser
 
Captain Bill's Avatar

Cruisers Forum Supporter

Join Date: Apr 2008
Location: On the boat
Boat: Endeavourcat Sailcat 44
Posts: 2,313
In my youth I was a biological researcher at what was then known as the Florida Institute of Marine Research in St. Petersburg Florida. I have read the paper and find that the conclusions that sunscreen and sunscreen ingredients, applied in the concentrations, used in a "closed system" do in fact cause coral bleaching. It says nothing about momentary exposure in an open system. The conclusion that this result threatens 10% of the worlds coral reefs is not supported by the results presented here. The authors provide no supporting calculations on the possible concentrations resulting from immersion of any numbers of bathers in the vicinity of a coral reef. In grad school I did toxicology work for the USEPA at the lab in Gulf Breeze Florida. Toxicology research in which one did not find a no impact concentration was considered invalid. This type of result would have been considered preliminary, justifying further research, but certainly not conclusive. This type of experiment did not require traveling to several coral reefs around the world, but could have been done in a laboratory using laboratory cultured corals. I suspect someone got themselves a grant to justify their travel itinerary.

These people do not seem to be qualified marine toxicologists. It should be noted that they did not quote any toxicology methodology references in their references section. The method used here is generally called a bioassay, but they did not use "standard" bioassay methodology. Until someone such as the EPA does a legitimate bioassay using standard bioassay methodology and realistic exposure levels I would not be concerned about using sunscreen near coral reefs.
__________________

__________________
Captain Bill is offline   Reply With Quote
Old 20-02-2009, 10:12   #33
Registered User

Join Date: Apr 2007
Location: Jupiter FL
Boat: temporarily boatless...
Posts: 723
Quote:
Originally Posted by sailorgal View Post
So don't be so quick to think that the authors of that paper had a personal agenda. Just because something doesn't seem likely to the untrained eye doesn't mean it ain't so.
As I wrote earlier, 10 ppm sunscreen in the water isn't unlikely, it's impossible (unless the Exxon Valdez is filled with sunscreen and then grounds on a coral reef).
__________________
pete33458 is offline   Reply With Quote
Old 20-02-2009, 10:40   #34
Senior Cruiser
 
Captain Bill's Avatar

Cruisers Forum Supporter

Join Date: Apr 2008
Location: On the boat
Boat: Endeavourcat Sailcat 44
Posts: 2,313
The calculation is fairly simple a 3 meter (about 10ft) cube of seawater contains 27000 liters of water. If we assume that there is no current and the swimmer/dive stays in the same cube until all of the sunscreen is dissolved and of course there is no current (not likely on a coral reef). We'll also assume that the person uses 50 ML of sunscreen. Then the concentration is 50/27,000,000 or about 1.85 microliters per liter. Roughly 1/5 of the lowest concentration used in the test. If we assume that an average tourist coral reef is 100 meters square and again with no current one would require 1,111 people to be in the water at the same time to reach this concentration. I have never seen a coral reef even in high tourist areas that have over 1000 people on them. Since there is no coral reef in the world that can survive 4 days with no current there is no way that the quoted paper is a realistic exposure level. Again an interesting preliminary result but it in no way supports a conclusion that this threatens coral reefs.
__________________
Captain Bill is offline   Reply With Quote
Old 20-02-2009, 11:11   #35
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,579
Images: 240
Quote:
Originally Posted by DeepFrz View Post
I love a good argument, especially when someone knows what they are talking about.
Me three.
I'm pleased to see the study beingrationally critiqued, rather being merely dismissed as "unsatisfactory".
Unfortunately, everyone, who knows anything, seems to know MUCH more than I do. Takes SOME of the fun out of it, for me.
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 20-02-2009, 11:34   #36
CF Adviser
Moderator Emeritus
 
Hud3's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: Virginia
Boat: Island Packet 380, now sold
Posts: 8,929
Images: 49
Darn good discussion! I usually roll my eyes when I see people making "scientific" pronouncements as if they were fact, based solely on what they personally consider to be a "logical" analysis of a topic, but without any impartial supporting data, first-hand or not. It's generally done to support an already-held, emotionally charged belief of one sort or another.

One thing a scientist learns early on is not draw conclusions based on what seems to "make sense", but to put personal opinion aside and work from empirical data, i.e., facts. I'm very gratified to see those with genuine training in the Scientific Method step forward to add perspective to the debate.
__________________
Hud
Hud3 is offline   Reply With Quote
Old 20-02-2009, 12:26   #37
Registered User
 
sailorgal's Avatar

Join Date: Feb 2005
Location: Panhandle Florida
Boat: 48' Hi Star
Posts: 211
Images: 3
Quote:
Originally Posted by Captain Bill View Post
The calculation is fairly simple a 3 meter (about 10ft) cube of seawater contains 27000 liters of water. If we assume that there is no current and the swimmer/dive stays in the same cube until all of the sunscreen is dissolved and of course there is no current (not likely on a coral reef). We'll also assume that the person uses 50 ML of sunscreen. Then the concentration is 50/27,000,000 or about 1.85 microliters per liter. Roughly 1/5 of the lowest concentration used in the test. If we assume that an average tourist coral reef is 100 meters square and again with no current one would require 1,111 people to be in the water at the same time to reach this concentration. I have never seen a coral reef even in high tourist areas that have over 1000 people on them. Since there is no coral reef in the world that can survive 4 days with no current there is no way that the quoted paper is a realistic exposure level. Again an interesting preliminary result but it in no way supports a conclusion that this threatens coral reefs.
Hey Capt. Bill
I agree that they didn't report any actual environmental measurements of the chemicals that they studying. Usually you want to use an "environmentally relevant" concentration of whatever chemical you are studying to make any kind of claim for an environmental effect. I have done studies on fish where we use nanogram/liter concentrations of estrogenic chemicals. Some of those concentrations are relevant concentrations downstream of sewage treatment effluent outflow.

The study in question does indicate that exposure to chemicals in sunscreens has the potential to cause coral bleaching, but they can't conclude that it will do so in a real world setting without a lot more study.

And you are right, they could have done this in a laboratory setting. I wish I could get a grant that would allow me to travel to all of these coral reefs!

When were you at the Gulf Breeze lab? Did I know you? I worked there from 1989 until 1991 and then did my PhD research there from 1997 until 2002. I'm currently collaborating with them on the coral study I'm doing. They've done the laboratory exposures, and now I'm going to do the microarray studies.

Small world!
__________________
How can I get lost?? I don't know where I'm going!
sailorgal is offline   Reply With Quote
Old 20-02-2009, 13:08   #38
Registered User

Join Date: Apr 2007
Location: - San Diego and Fort Collins, CO
Boat: 38' Homebuilt Cutter - "Atticus"
Posts: 136
While I am very happy to have sparked a great discussion on this topic, I was mainly interested if anyone had used the Organic Sunscreen or not, and if it works, which it sounds like from at least one post that it does.

Regardless of if you believe that sunscreen causes reef damage or not, it is hard not to look at the list of ingredients and see that some of them are quite toxic. I read in National Geographic Adventure Magazine that nearly 6000 TONS of sunscreen is washed away into the oceans off Mexico each year. How many PPM is that? Who know and who cares. That can not be good for reefs, fish, humans, the planet, or plankton. (Not in that order.)

I simply choose to live my life with as little impact on the environment as possible, not for profit or science, but so that I can look my son in the eyes in 15 years and tell him I did everything I could to try to change the course we are on.

After reading some of these posts, It makes me wonder some peoples thoughts on Climate Change or Evolution. Another thread perhaps...
__________________
Colorado Dreamer is offline   Reply With Quote
Old 20-02-2009, 13:29   #39
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,579
Images: 240
Atticus:
Appropriate clothing (dark t-shirt, wet suit, wetskin) also works as an effective sunscreen; and doesn’t wash off, nor (potentially) harm the environment.
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 20-02-2009, 13:32   #40
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,579
Images: 240
Quote:
Originally Posted by pete33458
... the single most common way to ACTIVATE a latent virus, in use since even before people knew what viruses were, is UV radiation (think cold sores and sunburn)...
Herpes Simplex Virus (HSV) I and II are frequently activated by sun exposure, colds, stress, and who knows what else?
However, ultraviolet radiation and heat has been demonstrated to kill the Severe Acute Respiratory Syndrome (SARS) coronavirus effectively.
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 20-02-2009, 14:02   #41
Senior Cruiser
 
Captain Bill's Avatar

Cruisers Forum Supporter

Join Date: Apr 2008
Location: On the boat
Boat: Endeavourcat Sailcat 44
Posts: 2,313
Hey Sailorgal, I predated you by about a decade. I worked there from the summer of 1978-summer 1980. Just to be clear I worked for a professor at UWF and we had grants at the lab that we worked on. I was not actually employed by the lab. I agree with you about nanogram concentrations, but these guys were testing milligram concentrations and in a closed system as opposed to an open system. My guess is that it might be possible to achieve nanogram concentrations for a short period of time in the vicinity of a bunch of people. Some of the work I did was on microcosms and would have been appropriate for a realistic test. One could dose the system at enviromentally relavant dose three or four time during the day to simulate diveboats dumping a bunch of people in the water and see what happens. Since these guys did not test a no effect dose we don't really know what the low end effect is. It would have been helpful to do something like expose them for an hour and see if it had the same effect as soaking the coral in a concentrated solution for 4 days. It certainly would have told us more. We didn't have microarrays when I worked there, I suspect that your techniques are a few generations more modern that what I did.
__________________
Captain Bill is offline   Reply With Quote
Old 20-02-2009, 14:25   #42
Registered User
 
sailorgal's Avatar

Join Date: Feb 2005
Location: Panhandle Florida
Boat: 48' Hi Star
Posts: 211
Images: 3
Quote:
Originally Posted by Colorado Dreamer View Post
I simply choose to live my life with as little impact on the environment as possible, not for profit or science, but so that I can look my son in the eyes in 15 years and tell him I did everything I could to try to change the course we are on.

After reading some of these posts, It makes me wonder some peoples thoughts on Climate Change or Evolution. Another thread perhaps...

I hear you on that Dreamer and I agree. That's why I do the work I do. Trying to do my part to help the planet. There is a Native American saying that I really think is appropriate:

We do not inherit the earth from our ancestors, we borrow it from our children.

And don't even get me started on the evolution or climate change topics !


As I stated in my first post, I don't know anything about the organic sunscreen products but I think I'll look for those next time I'm shopping for sunscreen. Potentially they are better for the planet, and for me!!


Capt. Bill -- I got my BS degree in Biology at UWF. Who was your professor?
__________________
How can I get lost?? I don't know where I'm going!
sailorgal is offline   Reply With Quote
Old 20-02-2009, 14:37   #43
Registered User
 
Martinini's Avatar

Join Date: Jul 2008
Location: Where ever my boat is.
Boat: Allied Princess 36'
Posts: 258
A scientist marine biologist has proven that there is only one common link to every dieing reef in the world, his research has been duplicated now several times. It turns out that a ground fungus from Africa is the culprit. The spores are picked up by the wind and into the atmosphere and transported world wide. This fungus once dropped on a reef not only survives but thrives by infecting the reef polyps and eventually killing them. In this enviorment the checks and balances that keep it in check on land aren't present in the Oceans. The extended droughts in Africa have created a problem no one had anticipated, and given the conditions aren't going to change the problem will continue. When he published his findings a few months ago he was po-poohd until others started duplicating the effect in labs all over the world! Who would have thunk it!!!
__________________
Martinini is offline   Reply With Quote
Old 20-02-2009, 14:41   #44
Senior Cruiser
 
Captain Bill's Avatar

Cruisers Forum Supporter

Join Date: Apr 2008
Location: On the boat
Boat: Endeavourcat Sailcat 44
Posts: 2,313
Sailorgal, Dr. D'asaro was my major professor, Drs. Rao and Collard were on my commitee. I'm sure you knew all of them.
__________________
Captain Bill is offline   Reply With Quote
Old 20-02-2009, 15:06   #45
Registered User
 
sailorgal's Avatar

Join Date: Feb 2005
Location: Panhandle Florida
Boat: 48' Hi Star
Posts: 211
Images: 3
Quote:
Originally Posted by Captain Bill View Post
Sailorgal, Dr. D'asaro was my major professor, Drs. Rao and Collard were on my commitee. I'm sure you knew all of them.
I sure did. I loved Dr. D'Asaro's developmental biology class.

Martinini -- do you have a reference for that publication? I'd be interested to read it. I hadn't heard that before. Thanks!
__________________

__________________
How can I get lost?? I don't know where I'm going!
sailorgal is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Sun Power E19/240W? mrybas Electrical: Batteries, Generators & Solar 15 24-04-2013 14:58
Standard Horizon CP300 I Screen Went Blank Gerry Connolly Navigation 3 23-08-2011 12:27
Black Taylor Made Fender Cover Turns Black from Sun ospreyman Product or Service Reviews & Evaluations 2 19-07-2011 10:38



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 20:03.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.