Page 28 - ARUBA TODAY

A28 SCIENCE
Tuesday 26 June 2018

Warming drives spread of toxic algae in U.S., researchers say

By TOM JAMES
Associated Press
SALEM, Ore. (AP) — The
words blasted to cell-
phones around Oregon’s
capital city were ominous:
“Civil emergency . prepare
for action.”
Within half an hour, a sec-
ond official alert clarified
the subject wasn’t impend-
ing violence but toxins from
an algae bloom, detected
in Salem’s water supply.
Across the U.S., reservoirs
that supply drinking wa-
ter and lakes used for rec-
reation are experiencing
similar events with growing
frequency. The trend rep-
resents another impact of
global warming and raises
looming questions about
the effects on human
health, researchers say.
“When water bodies warm
up earlier and stay warmer
longer ... you increase the
number of incidents,” said
Wayne Carmichael, a re-
tired Wright State University
professor specializing in the In this Sept. 20, 2017 file photo, a catfish appears on the shoreline in the algae-filled waters of North Toledo, Ohio.
organisms. “That’s just logi- Associated Press
cal, and it’s being borne when blooms occur. Chapra led a team in- rich fertilizers are used, lasting longer, and their
out.” But less is known about ex- cluding scientists from the Chapra said. peaks seem to be getting
Technically called cyano- posure at lower doses, es- Massachusetts Institute of In Utah, a 2016 algae bigger,” Holcomb said. “I
bacteria, the ancient class pecially over the long term. Technology and the U.S. bloom in a recreational-use don’t think any state is iso-
of organisms that create Small studies have linked Environmental Protection lake sickened more than lated.”
the blooms are present exposure to liver cancer Agency in one of the most 100. When the story made In Lake Erie, a major bloom
nearly everywhere water — one toxin is classified as comprehensive studies national headlines, other in 2014 caused authorities
is found but thrive in warm, a carcinogen, and others of the interplay between states reached out. to warn against drinking
still bodies like lakes and have pointed to potential global warming and the “We started getting calls tap water in Toledo, Ohio,
ponds. They also create a links to neurodegenera- blooms, published in 2017. from other health depart- for more than two days,
unique class of toxins, the tive disease. But definitively Because they prefer warm ments all over the country cutting off the main wa-
impact of which on hu- proving those links would water, higher summer tem- saying, ‘Hey, we’re deal- ter source for more than
mans is only partly under- require larger studies, said peratures and more fre- ing with an algal bloom in 400,000 people.
stood. Carmichael, who helped quent heat waves help the a lake that has never ever Now blooms happen ev-
Long linked to animal the World Health Organi- organisms. More frequent had one before,’” said ery year in Utah and Ohio.
deaths, high doses of the zation set the first safe ex- droughts also cause reser- Aislynn Tolman-Hill, Utah Officials in both states say
toxins in humans can cause posure standards for the voirs to be shallower in sum- County Health Department they’ve largely been able
liver damage and attack toxins. mer, causing them to warm spokeswoman. to stop them from toxify-
the nervous system. In the “It’s absolutely certain in faster. Officials only recently start- ing drinking water. But
largest outbreaks, hun- my mind that warming tem- And more intense rain- ed carefully logging the the blooms can still sicken
dreds have been sickened peratures are going to end storms, also conclusively blooms, but they seem people and pets that go
by blooms in reservoirs and up causing more of these linked to climate change, to be becoming more in- in the water, and often hit
lakes, and officials in some algal blooms,” said Steven can wash more nutrients tense, said Ben Holcomb, a recreation businesses that
areas now routinely close Chapra, an environmental into lakes and reservoirs, es- biologist for Utah’s environ- depend on lake access.
water bodies used for rec- engineering professor at pecially from farms where mental agency. “They’re Other blooms, including
reation and post warnings Tufts University. nitrogen and phosphorous- starting earlier, they’re flare-ups affecting drinking
water, have been logged
in recent years in New York,
Florida and California.
In Oregon, officials lifted
Salem’s drinking water ad-
visory after several days,
but then had to re-issue the
warning. The water supply
serves a population of just
over 150,000 in the city,
along with residents out-
side city limits.q