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Photo of Shinn Gene Shinn
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Gene Shinn is a Research Geologist for the USGS- Center for Coastal Geology in St. Petersburg, Florida. After obtaining his degree in Zoology from the University of Miami in 1957, Shinn spent a year at the University's Marine Laboratory. In 1958, he began working for Shell Oil Company as a research geologist. He joined the United Sates Geologic Survey (USGS) in 1974.

Currently, Shinn monitors and tracks groundwater in the Florida Keys and Florida Bay and investigates the effects of African dust on Caribbean coral reefs. He also studies the general health of coral reefs throughout the Caribbean.

The author of some 200 peer-reviewed publications, Shinn is also a diver and was the National Spearfishing Champion of 1958. An accomplished musician, Shinn plays percussion in the Tampa Bay Symphony.

     

For links to this scientist's home page and other related infomation please see our resources page

Shinn responds :

11.07.01 Arun asks:
Hi,
I would like to introduce myself as a Fellow working in the Program in Infectious Disease in Fred Hutchinson Cancer Research Institute, Seattle, WA. My area of specialization is Mycology and right now, I am working with Aspergillus fumigatus. I am just curious to know about which species of Aspergillus is destroying sea corals. Where can I read more about it?
Thanks

Shinn's response:
Dear Arun, the species is Aspergillus sydowii. As you know it is a common soil fungi and cannot reproduce in seawater. The spores however do grow when they land on a suitable substrate such as a seafan. Since that work was done, we have identified several other species as well, including fumigatus. For further information see:

- E. A. Shinn, G. W. Smith, J. M. Prospero, P. Betzer, M. L. Hayes, V. Garrison, R. T. Barber. 2000. African Dust and the Demise of Caribbean Coral Reefs. Geol. Res. Lett. 27, 3129-3032

- D. A. Griffin, C. A. Kellogg, and E. A. Shinn, 2001, Dust in the wind long range transport of dust in the atmosphere and its implications for global and ecosystem health, Global Change and Human Health, 2, no. 1, pp. 2-15.

- D. W. Griffin, V. H. Garrison, J. R. Herman, and E. A . Shinn. 2001. African desert dust in the Caribbean atmosphere: microbiology and public health. Aerobiologia. Vol 17 p. 203-213 . Prospero, J. M., and Nees, R. T., 1986, Impact of the North African drought and El Nino on mineral dust in the Barbados trade winds, NATURE Vol. 320, No. 6064, pp. 735-738. Smith, G. W., Ives, L. D., Nagelkerken, I. A., Ritchie, K. B., 1996, Caribbean sea-fan mortalities, NATURE Vol. 383. 10 Oct. p487. also see 4 page info sheet in http://coastal.er.usgs.gov/african_dust/ and the mini movie at http://coastal.er.usgs.gov/african_dust/dust-documentary.html

11.11.01 Dominique asks:
In what way may human behavior play a role in the increasing dust particles in the wind?

Shinn's response:
Dear Dominique,
The drought in the Sahel region of north Africa began in 1970. At that time human population began increased along with agriculture and overgrazing of livestock. Lake Chad, which was about 100 miles long in 1970, has dried to a small pond because of drought and diversion of it's waters for irrigation. The dried lakebed is a major source of the soil dust that crosses the Atlantic.

The nomadic and pastoral people of the Sahara and Sahel have many sheep, goats, and either donkeys or camels. The hooves of these grazers breakup the armoring of the soil, exposing the fine particles to the wind. Also,the cutting of vegetation for firewood and browsing of the scant vegetation by goats, has reduced the amount of vegetation, allowing the soils to dry and be more prone to atmospheric transport. The larger scale effects include the effects of biomass burning and combustion of fossil fuels as well as climate, including rainfall and changes in hemispheric pressure systems.
Best Wishes,
Gene

11.07.01 Henry asks:
Dr. Shinn, Wanted to let you in on a fact you might find interesting, related to African Dust blowing across the Atlantic:

In 1997 I sailed a small boat from Bermuda to Tortola in the British Virgin Islands. The trade winds from Africa do not blow as far north as Bermuda, but start somewhere around 20 - 25 degrees North Latitude.

Within minutes of hitting the strong easterly trade winds, I could smell the dirt of Africa. This strong smell was reminiscent of the dirt of a farm, dug up with a shovel. It was so apparent that I never had any doubt what it was, although the rest of the crew was skeptical.

Watching the show and hearing 91' and 97' were particularly bad dust years in Africa confirmed my belief.

Here is a question: do you believe that this dirt makes it's way all the way to US soil? What is it's effect there? Regards,
Henry

Shinn's response:
Dear Henry,
I believe you. I have smelled that smell on several occasions here on the west coast of Florida and in the Florida Keys. In 1988 a friend was sailing near Granada when hoards of 2-3 inch long African locusts came down on his boat. That event is well-documented in the scientific literature but it seems that few people paid much attention to the event. As for African dust in the US it is also documented. See: Perry, D. D., Cahill, T. A., Eldred, R. A., and Dutcher, D. D., 1997, Long-range transport of North African dust to the eastern United States, Journal of Geophysical Research, Vol. 102, No. D10, P 11,225-11,238. In this study the researchers placed dust collectors in National Parks east of the Rockies (and in the Virgin Islands) and found African dust in all of them. About 40 percent of the dust collected at Carlsbad, NM was African in origin. It is fairly well known that the beautiful sunsets on the west coast of Florida between June and October are due to African dust. We suspect, but have not proved, that the dust brings the bacteria that causes citrus canker to orange and other citrus trees in south Florida. The disease often breaks out following passage of hurricanes. Hurricanes bring large amounts of dust because they usually begin in the same areas that supply the dust. Hurricanes also provide a warm moist environment that is most suitable for microbes.
Best Wishes,
Gene

11.07.01 Jack P. asks:
It was mentioned that there may also be a link between all this dust from Africa causing an increase in asthma in the Caribbean and possibly USA as well. Can you point me to the source of this research?
Thanks very kindly,
Jack P. Potomac, Maryland, USA

Shinn's response:
Dear Jack,
there are two good references for the increase in asthma in Barbados and Trinidad. It is also well know in Puerto Rico but do not have a standard reference for PR. The reference are:

Howitt, M. E., 2000, Asthma management in the Caribbean-an update, Postgraduate Doctor Caribbean, vol. 16, no. 2, p. 86-104.

Monteil, M. A., Juman S.,m Hassanallly, R. Williams, J, O, Pierre, L., Rahamank M., Singh, H. Trinidade, A, 2000, Descriptive Epidemiology of Asthma in Trinidad, West Indies, Joural of Asthma vol. 37 No. 8 pages 677-684.

Also see:
Griffin, D. W., Garrison V. H., Herman, J. R. and Shinn, E. A., 2001, African Desert Dust in the Caribbean Atmosphere: Microbiology and Public Health. Aerobiologica, July 2001. Griffin D. W., Kellogg, C. A. and Shinn E. A., 2001 Dust in the wind, Global change and Human Health, vol. 2, No. 1. P. 2-15.

Holmes Hanna, 2001,The secret life of dust, John Wiley and Sons, (ISBN: 0471377430) 240 pages.

11.06.01 Nathan P. asks:
Dr. Shinn -- The broadcast of this show was my first exposure to the role of Aspergillus in the well-known phenomenon of coral bleaching. It is certainly an important advance to know the precise pathogen which is directly acting to the detriment of coral. One issue which you must have considered: Aspergillus has existed for aeons, yet massive coral bleaching has only recently been identified as a problem.

Do you see Aspergillus as the proximate cause, the root cause, or merely one among several agents contributing to the problem of coral death or 'bleaching'? What are the public policy implications? Would this let other hypothesized or theorized causes such as pollution, ocean warming, or ozone depletion off the hook?

Shinn's response:
Dear Nathan,
We are not saying all coral diseases are caused by African dust. Certainly Aspergillus sydowii has been shown to cause a disease in seafans but it has not been implicated in coral bleaching. Bleaching is most likely caused by warming or at the very least warming weakens the coral allowing other diseases to take hold. Our study does not let other forms of pollution off the hook, however, this study has only just begun, who knows what we may learn in the future. Recent study revealed over 120 viable (live) microbes in the dust reaching the Caribbean. We have not determined what effect these microbes have on corals. Although dust has been transported from Africa for a long time, the type of microbes and the kinds of chemicals may have changed. Certainly pesticides, plasticizers and various combustion products were not being transported until the last couple of decades.

Please see the 4 page info sheet at: http://coastal.er.usgs.gov/african_dust/ and the mini movie at http://coastal.er.usgs.gov/african_dust/dust-documentary.html

You can learn more in the following publications:

Griffin, D. W., Garrison V. H., Herman, J. R. and Shinn, E. A., 2001, African Desert Dust in the Caribbean Atmosphere: Microbiology and Public Health. Aerobiologica, July 2001.

Griffin D. W., Kellogg, C. A. and Shinn E. A., 2001 Dust in the wind, Global change and Human Health, vol. 2, No. 1. P. 2-15.

Holmes Hanna, 2001,The secret life of dust, John Wiley and Sons, (ISBN: 0471377430) 240 pages.

Shinn, E. A., Smith, G. W., Prospero, J. M., Betzer, P., Hayes, M. L., Garrison V., Barber R. T., 2000, African dust and the demise of Caribbean coral reefs, Geophysical Research Letters, V. 27, No. 19, p. 3029-3032.

Best Wishes, Gene

11.09.01 James asks:
I watched "Dust Busting" with great interest. Our daughter has been extremely ill since the end of June when she returned from a vacation in the Caribbean. She has lost about 15 pounds and has had a fever for about four months now. Could you please direct me to sources where I might further investigate some of these airborne diseases affecting the Caribbean? Anything that can be done to help our daughter would be invaluable. After innumerable doctor visits, she has yet to be diagnosed. Thank you.

Shinn's response:
Dear James,
This is the toughest question we have received. We can not provide a sure answer but can share our concern. There is no standard work on diseases carried in African dust because no one ever did the necessary research. We have identified hundreds of viable microbes in the dust reaching the Caribbean including Bacillus. That Bacillus can easily make the transatlantic trip demonstrates why this kind of research is so necessary. The paper by Dale Griffin and others (reference below) identified opportunistic human pathogens (8 percent of those identified to species level) using DNA and PCR. This work has only just begun and we feel that further sampling and study will eventually reveal many other human pathogens. The dust is blowing from a region of Africa that has nearly every disease know to mankind. We hope to raise additional funding to further this study because we know it is very important. What you are describing is an especially good example of why this kind of research should be done. To our knowledge no government agency is presently doing this kind of research. I really wish we could provide a clear answer. The two references provided below further point out the importance of this research.

As a suggestion, have any of the doctors considered Valley Fever? This disease is carried in dust and affects many people in the SW especially in Arizona. It is caused by a soil fungi called Coccidioides immitis. It has not yet been identified in African dust but it is likely to be present. Your daughter should definitely see an MD who specializes in tropical diseases - there are a number of diseases in the Caribbean which although uncommon, could have long-term effects - some are parasites and others viruses. Perhaps someone at Washington Hospital in Washington DC or at the Centers for Disease Control. It would be especially important to determine if your daughter has the mosquito-borne disease called Dengue fever. It is common in Puerto Rico and other areas of the Caribbean.
Good luck and best Wishes, Gene

Griffin, D. W., Garrison V. H., Herman, J. R. and Shinn, E. A., 2001, African Desert Dust in the Caribbean Atmosphere: Microbiology and Public Health. Aerobiologica, July 2001.

Griffin D. W., Kellogg, C. A. and Shinn E. A., 2001 Dust in the wind, Global change and Human Health, vol. 2, No. 1. P. 2-15.

For additional information see the new book: Holmes Hanna, 2001,The secret life of dust, John Wiley and Sons,
(ISBN: 0471377430) 240 pages.

Also see the 4 page info sheet in http://coastal.er.usgs.gov/african_dust/

11.09.01 James asks:
I watched "Dust Busting" with great interest. Our daughter has been extremely ill since the end of June when she returned from a vacation in the Caribbean. She has lost about 15 pounds and has had a fever for about four months now. Could you please direct me to sources where I might further investigate some of these airborne diseases affecting the Caribbean? Anything that can be done to help our daughter would be invaluable. After innumerable doctor visits, she has yet to be diagnosed. Thank you.

Shinn's response:
Dear Bob,
The dust began to increase with the drought that began in North Africa in 1970. The drought is ongoing and made all the worse by over farming and over grazing. There is no sewage or garbage disposal in North Africa...it all goes into the rivers or on the ground or is burned. During the dry season whatever went in the flooding rivers during the wet season dries out during drought and becomes airborne. For complete documentation of the relation between the drought and dust reaching the Caribbean and the Americas see:

Prospero, J. M., and Nees, R. T., 1986, Impact of the North African drought and El Nino on mineral dust in the Barbados trade winds, NATURE Vol. 320, No. 6064, pp. 735-738.

Prospero, J.M. Long-term measurements of the transport of African mineral dust to the southeastern United States: Impact on regional air quality.1999, J. Geophys. Res., 104(D13), 15,917-15,927.
Best wishes, Gene

11.09.01 Paul asks:
In your recent program about the fungi in the corals in the Caribbean, it was said to have been caused by a "Dust bowl" like situation from Africa from farming. I found this interesting but was confused because usually the winds from North America blow West to East - The Westerlies as they are called here in Canada. My question is- how can they blow to the Virgin Islands in this direction? I love your show and keep up the outstanding work.

Shinn's response:
Dear Paul, Actually the trade winds blow from east to west. The westerlies lie in a belt farther north. This dust is not a high level phenomena. Most of it moves with the trades below 10,000 ft.

for more detailed information see:

Prospero, J. M., and Nees, R. T., 1986, Impact of the North African drought and El Nino on mineral dust in the Barbados trade winds, NATURE Vol. 320, No. 6064, pp. 735-738.
Best Wishes, Gene


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