View previous topic :: View next topic |
Author |
Message |
purple
Joined: 30 Apr 1998 Posts: 15
|
Posted: Fri Aug 31, 2007 1:29 pm Post subject: Microcystis Health Effects |
|
|
For folks interested in more information about the health effects of Microcystis, the following website gives a nice, readable summary:
http://www.floridamarine.org/features/view_article.asp?id=25259
Here is a relevant excerpt. The bottom line is that if you are careful, sailing at Sherman Island may produce nothing worse than a rash. Since life is all about weighing relative risks, you be the judge....
Health Effects
Microcystins are hepatotoxins (toxins that acts upon the liver) and known tumor promoters. If people drink water contaminated by microcystins, symptoms of exposure include nausea, vomiting and, in very rare but severe cases, acute liver failure. Reported health effects from cyanobacteria in humans are highly uncommon in the United States.
Although the likelihood of people being affected by a Microcystis bloom is low, minor skin irritation can occur with contact, and gastrointestinal discomfort can also occur if water from a bloom is ingested. People recreationally exposed (e.g., personal watercraft operators) to microcystins have also reported minor skin irritation. Health problems may occur in animals if they are chronically exposed to fresh water with Microcystis present. Just as livestock and domestic animals can be poisoned by drinking contaminated water, fish and bird mortalities have been reported in water bodies with persistent Microcystis blooms.
To limit exposure to microcystin toxin:
-Avoid or limit exposure to water containing high concentrations of Microcystis. This includes swimming and any activity resulting in accidental immersion.
-Do not allow children or pets to play in water containing a bloom.
-Never drink untreated water containing a Microcystis bloom, and do not let pets or livestock drink the water.
-Do not use herbicides to kill Microcystis cells because this will release the toxins directly into the water.
If exposed, wash the area thoroughly with clean water. Also thoroughly wash the fur of a pet that has been swimming in waters containing Microcystis. |
|
Back to top |
|
|
jwallace
Joined: 09 May 1998 Posts: 124 Location: SF Bay Area
|
Posted: Fri Aug 31, 2007 2:10 pm Post subject: Is all Blue-Gree algae bad? |
|
|
I sail at SI and will be holding off until I hear otherwise. However, I was curious if the Blue-Green algae that I've heard about at Clear Lake is a similar concern. I was recently invited (which was since canceled for other reasons) to water ski at Clear Lake and your post made me think about the Blue-Green algae there (not to mention the Mercury issues).
Thx so much for posting this info!!!! |
|
Back to top |
|
|
npure2001
Joined: 15 Mar 2003 Posts: 51 Location: Far East Bay
|
Posted: Fri Aug 31, 2007 2:35 pm Post subject: |
|
|
Glad you posted this. While the implied high levels of a carcinogenic hepatotoxin in the river water doesn't give me real comfort, it's important that the risks are carefully weighed.
(Lotsa fair skinned windsurfers are exposed to the California sun with much greater health risks. As recently noted, some sunscreens don't provide good protection at all, yet too many just slap it on and feel safe.)
All in all, with prudent practices (I'll wear my daily use lenses in the Delta, make sure that I don't have open cuts, don't ingest any river water and rinse off thoroughly after a session), one can probably remain reasonably safe. Fortunately, the algae blooms are highly visible, so one can visually verify water quality to a great degree (contrast that to lots of other things that are way more harmful yet invisible: e.g. mercury, cadmium, cyanide, pesticides, etc.). Exposure is anyway probably detected by a quick onset stomach flue. While not a great pleasure, that can be used as a warning as to not to repeat the practice without long term consequences.
$0.02
Gabor
P.S. I don't wear a life jacket. Would impede sail handling in freestyle moves. |
|
Back to top |
|
|
purple
Joined: 30 Apr 1998 Posts: 15
|
Posted: Fri Aug 31, 2007 3:18 pm Post subject: Clear Lake Blooms |
|
|
Regarding Clear Lake, there are three major species of blue green algae that bloom there. Microcystis is definitely one of them, so this could have been why there was warning there.
For more information about Clear Lake & its algal blooms, check out:
http://www.des.ucdavis.edu/faculty/Richerson/Clear%20Lake%20overview.pdf |
|
Back to top |
|
|
jwallace
Joined: 09 May 1998 Posts: 124 Location: SF Bay Area
|
Posted: Fri Aug 31, 2007 3:41 pm Post subject: Thanks, Doc! |
|
|
jw |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You can attach files in this forum You can download files in this forum
|
|
|