g******4
发帖数: 6339 | 1 【 以下文字转载自 Chicago 讨论区 】
发信人: gogo2004 (挑灯看剑), 信区: Chicago
标 题: 小孩家长必看::[视频] 上百万只蜜蜂离奇死亡，咋回事？
发信站: BBS 未名空间站 (Sun Jan 12 15:29:06 2014, 美东)
看来，首先不能让小孩吃蜂蜜
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Pesticides
Further information: Pesticide toxicity to bees, Imidacloprid effects on bee
population, and Bees and toxic chemicals
According to the U.S. Department of Agriculture, pesticides may be
contributing to CCD.[49] Scientists have long been concerned that pesticides
and possibly some fungicides may have sub-lethal effects on bees, not
killing them outright but instead impairing their development and behavior.
Of special interest is the class of insecticides called neonicotinoids,
which contain the active ingredient imidacloprid, and similar other
chemicals, such as clothianidin and thiamethoxam. Honey bees may be affected
by such chemicals when they are used as a seed treatment because they are
known to work their way through the plant up into the flowers and leave
residues in the nectar. Scientists note that the doses taken up by bees are
not lethal, but they are concerned about possible chronic problems caused by
long-term exposure.[21] Most corn grown in the US is treated with
neonicoticoids and a 2012 study found high levels of clothianidin in
pneumatic planter exhaust. In the study, it was found that the insecticide
was present in the soil of unplanted fields near those planted with corn and
on dandelions growing near those fields.[50] Another 2012 study done in
Italy also found clothianidin and imidacloprid in the exhaust of pneumatic
seeding equipment.
.....
In 2013, researchers collected pollen from hives on the east coast and fed
it to healthy bees. The pollen had an average of nine different pesticides
and fungicides. Further, the researchers discovered that bees that ate
pollen with fungicides were three times more likely to be infected by
parasites. Their study shows that fungicides, thought harmless to bees, may
actually play a significant role in CCD. Their research also showed that
spraying practices may need to be reviewed because the bees sampled by the
authors foraged not from crops, but almost exclusively from weeds and
wildflowers, suggesting that bees are more widely exposed to pesticides than
thought.[84]
Neonicotinoids banned by European Union
Early in 2013, the European Food Safety Authority issued a declaration that
three specific neonicotinoid pesticides pose an acute risk to honeybees, and
the European Commission (EC) proposed a two-year ban on them.[85] David
Goulson, who led one of the key 2012 studies at the University of Stirling
said that the decision "begs the question of what was going on when these
chemicals were first approved." The chemical manufacturer Bayer said it was
"ready to work with" the EC and member states.[86] In April 2013, the
European Union voted for a two-year restriction on neonicotinoid
insecticides. The ban will restrict the use of imidacloprid, clothianidin,
and thiamethoxam for use on crops that are attractive to bees. Eight nations
voted against the motion, including the British government which argued
that the science was incomplete.[87]
Initiatives to ban neonicotinoids in the United States
In March 2013, professional beekeepers and environmentalists jointly filed a
lawsuit against the United States Environmental Protection agency for
continuing to allow the use of neonicotinoids in the United States. The suit
specifically asks for suspension of clothianidin and thiamethoxam. The
lawsuit follows a dramatic die off of bees in the United States, with some
beekeepers losing fifty percent of their hives.[88] The EPA responded to the
suit by issuing a report blaming the Varroa mite for the decline in bees
and claiming that the role of neonicotinoids in bee extinction has been
overstated.[89] Meanwhile Congress is considering the Save America's
Pollinators Act of 2013 (H.R. 2692).[90] The proposed act, spearheaded by
Representatives John Conyers (D, MI) and Earl Blumenauer (D, OR), and co-
sponsored by Rep. Lucille Roybal-Allard (D, CA) and Rep. Carol Shea-Porter (
D, NH), asks that neonicotinoids be suspended until a full review of their
impacts has occurred. The Save America's Pollinators Act was drafted
immediately following the largest documented die off of bees in the United
States which took place in the parking lot of a department store in June
2013. The neonicotinoid Safari, which had been sprayed on linden trees, was
suspected of killing the bees.[91][92]
http://en.wikipedia.org/wiki/Colony_collapse_disorder#Possible_ |
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