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Sunday, January 31st, 2010 | Author: DNR

Report on Bee Mortality and Bee Surveillance in Europe

from http://www.isaaa.org/kc/cropbiotechupdate/online/default.asp?Date=12/18/2009

AFSSA, the French Food Safety Agency completed a 218-page report on honey bee mortality and the ways that colony losses are monitored in Europe, December 8, 2009. The European Food Safety Authority commissioned the study and published the report. Initially, AFSSA set up a consortium of seven European bee disease research institutes in France, Germany, Italy, Slovenia, Sweden, Switzerland, and the United Kingdom.

The project covers 1) a description and critical analysis of surveillance programs that measured colony loss; 2) the collection and analysis of the epidemiological data sets on colony losses; and 3) a critical review and selection of relevant literature on the possible causes and risk factors of colony losses.

The researchers found that bee colony losses in Europe and the USA are multifactorial which include beekeeping and husbandy practices, environmental factors, biological agents as well as excessive use of pesticides. The interaction of these factors create stress, weaken bees’ defense system allowing pests and pathogens to kill the colony.

3.2.3.3 Chemical agents

The debate on chemical agents is mainly concentrated on the agrochemicals used for crop treatments. Neonicotinoids are the focus of the greatest interest in the literature (imidacloprid, clothianidin and fipronil); other publications just mention “pesticides” in general, but certainly with an implicit consideration of neonicotinoids (Figure 75). Scientists are clearly divided on the role of these pesticides, as illustrated in Table 14. Although no involvement of pesticides has been proven for colony losses or CCD, a significant amount of pesticide residues are frequently found in the studies analysing bees, pollen and wax, usually at sublethal levels. A question arises, therefore, about the possibility for a conjunction of chemical residues present in the hive at sublethal concentrations, which may produce a lethal effect or clinical signs affecting the ability of colony to survive. Several authors mention these pesticides as factors contributing to stress or weakening of colonies which, once again, may “open the door” to other causative factors.

3.2.3.2 Biological agents

A significant number of biological agents are reported to be involved in colony losses. Viruses are the biological agents most frequently mentioned (Figure 73). As more than 15 different viruses are known to infect bees, often without any clinical symptoms and since, co-infection with several viruses is not uncommon, they are the subject of much research. Due to their frequent presence, they are found in many colony losses cases where it is very difficult to determine whether they are at the origin of the losses, or just co-factors. Of the eight viruses mentioned in the literature, IABPV is the most frequently mentioned, and some scientists consider it as a “marker” of CCD in the United States (Figure 74). Varroa, Nosema spp and Acarapis woodi infections are the three other most commonly mentioned biological factors. Some scientists consider them to be causative factors in a certain amount of colony losses (for Nosema mainly in Spain). Others consider that they are co- factors, contributing to the stress of the colony or contributing to the “expression” of colony mortality as causative factor of death for a colony already weakened by other stress factors. This is why the factors “multiple infection” and “unidentified disease” appear in the assumptions made by the authors. All these hypotheses open the floor to a debate on possible treatments to prevent or cure these infections. This links together these biological agents with chemical factors and beekeeping practices because beekeeping practices and chemical treatments are used to control infections. The debate on the involvement of the various biological agents is clearly expressed in the author’s opinions summarised in Table 13 with a high rate of “possible involvement” and balanced reports between “unlikely” and “very likely”.Scientific Report on Bee Mortality and Bee Surveillance in Europe

3.2.4 Conclusion and perspectives

The work package on literature review allowed the development of a specific methodology for literature search and analysis. The “priority 1″ references selected and reviewed validate the objectivity of the literature search which is expressed through the variability and the balanced topics included. The results of this work regarding risk and causative factors involved in colony losses have to be taken as a “snap shot” of the scientific community’s opinion as they are today; these are also “time sensitive”, and evolving due to the amount of ongoing research which will likely lead to new findings and a better understanding of the factors involved in the coming months or years.

To summarise this picture, common consensus amongst the scientific community about the multi-factorial origin of colony losses in Europe and in the United States (in the two aspects of this term: combination of factors at one place and different factors involved according to place and period considered) suggests the following factors are important, namely: beekeeping practices (feeding, migratory beekeeping, colony husbandry, treatments applied and so forth), environmental  factors (climate, available forage, biodiversity, etc.), chemical factors (pesticides) or biological agents (Varroa, Nosema spp, etc.) which together create stress, weaken bees’ immune systems that then allow pests and pathogens to kill the colony (e.g. one or several parasites, viruses, etc.).

Figure78. Factors involved in colony losses

Questions remain about the sequence of events that lead to colony mortality, and future studies should be designed and conducted to address this:

- There are many inconsistencies in the ways in which “colony losses” are defined. Up to 17 different definitions for CCD in the literature. This means that involved persons may not always be referring to the same phenomenon, and this creates confusion when trying to explain the origin of what has been identified in the field. The described pathology is varied, with authors/using the same descriptions for different sets of circumstances. A specific study should be undertaken to clearly categorise and quantify the various expressions of colony losses in the field. This study will be closely linked to the strengthening of surveillance systems;

- High concentrations of pesticides have rarely been identified in relation to colony losses (CCD in USA and winter colony losses in Europe) although acute events of pesticide toxicity are well described during the production season (and clearly differentiated from CCD and winter colony losses). However, the questions of possible synergistic effects of various pesticides and the effect of chronic exposure to sublethal doses of pesticides remains, and requires further investigation;

- Biological agents such as parasites, viruses or bacteria, alone or in combination, have clearly been identified as important factors in colony losses. Nevertheless, there is still a lack of knowledge about the exact mechanisms and/or interactions involved, that must also be addressed;

- Even though the multifactorial origin of colony losses is well acknowledged, the respective role of each factor as a risk or causative agent is unknown, and no hierarchy of relative threat posed by each one has been established. These matters require further investigation using appropriate epidemiological studies (case control and longitudinal studies).

Conclusion

This bee surveillance project sought information on both the prevalence of honey bee colony losses, and the surveillance systems respectively in 27 European countries. Through a standardised questionnaire, each of the surveillance systems collecting these data was evaluated. In addition, a thorough literature search of the existing databases, as well as relevant grey literature about causes of colony losses was completed, and the literature evaluated.

The main conclusions from project activities can be summarised as follows:

  • General weakness and high variability of most of the surveillance systems in the 25 systems investigated;
  • Lack of representative data at country level and comparable data at EU level for colony losses;
  • Common consensus of the scientific community about the multifactorial origin of colony losses in Europe and in the United States and insufficient knowledge of causative and risk factors for colony losses.

From these finding the consortium makes the following recommendations:

1. Implementation of a sustainable European network for coordination and follow-up of surveillance, and research on colony losses to underpin monitoring programmes;

2. Strengthen standardization at European level by harmonization of surveillance systems, data collected and by developing common performance indicators;

3. Build on the examples of best practice found in existing surveillance systems on communicable and notifiable diseases already present in some countries;

4. Undertake specific studies that build on the existing work in progress to improve the knowledge and understanding of factors that affect bee health (for example stress caused by pathogens, pesticides, environmental and technological factors and their interactions) using appropriate epidemiological studies (case control and longitudinal studies);

5. The set up of the coordination team at European level. This is a crucial issue and the coordination team should be organized in such a way so as to ensure its sustainability and to enable effective surveillance programme activities at the European level.

Complete report attached and also here: http://www.efsa.europa.eu/en/scdocs/scdoc/27e.htm

When their link breaks, download the PDF here: Scientific Report on Bee Mortality and Bee Surveillance in Europe

Monday, March 16th, 2009 | Author: DNR

What does LD50 mean? What about TLV?

LD50 stands for Lethal Dose 50. It is the amount of a material that, when administered to a population of animals or insects at the stated level, will be lethal for 50% of the population tested. For example and LD50 of 0.015 ?g / bee means that 15 trillionths of a kilogram will kill 50% of the bees that are exposed. The LD50 is established during safety testing conducted during product development. (return to What Has Been Found)

TLV, or Threshold Limit Value, on the other hand, is an occupational exposure level frequently printed on the MSDS (Material Safety Data Sheet) or label of a product. It is the maximum level to which a person can be safely exposed to that product when in use in accordance with the personnel protective equipment described on the label. The level is the amount believed a worker can be exposed day after day for a working lifetime without adverse health effects. The TLV does not relate to the amount that can be safely ingested as TLV values are typical inhalation or skin exposure related.

MORE GREAT DETAILS about CCD and pesticides: http://montcobee1.farming.officelive.com/CCDUpdate.aspx

Friday, March 13th, 2009 | Author: DNR

UPDATE 3/14/09 - The Greenwich Post newspaper reported in 2008 that McNitt’s honey testing “found no trace of another insecticide called Imidacloprid“… Jim McNitt commented on my first post, however, that Eliza just won again this year two top Life Science prizes at the 2009 Connecticut Science Fair for her continued research on pesticides in honey (read his blog). Most notably, he writes that she in fact did find imidacloprid in her testing. “This year, Eliza used HPLC to examine pollen, beeswax,Eliza McNitt 2009 Photo by Frank LaBanca beebread and dead bees gathered from the Arboretum hive for traces of imidacloprid… Her work confirmed the presence of high levels of imidacloprid both in the hive and on the extremities of the Arboretum honey bees.” So, what’s the story behind the story, here? Why did the newspaper report the contrary? Did last year’s research methods differ from this year’s? Was there a sudden spike in imidacloprid usage near the Arboretum study location in the past year? Stamford, CT is a place of wealth and immaculate lawns. It would be nice to see a survey of the gardeners and home owners about what products they put on the lawns. Do they use any of those recently banned in Canada? Would the local garden supply shops provide stats on sales of certain products for local research purposes? Mr. McNitt says’s he’ll send me the link to her research PDF for us to post here. I can’t wait. Thanks for keeping us posted. [his response and link is here : McNitt 2008 Research.pdf] (Photo by Frank LaBanca)

  • What are the possibilities of other high school students around the country sending samples to Greenwich High School Paperfor testing?
  • Could there be a continuing research program set up there?
  • What are the costs to the school for conducting the tests?
  • Is it complicated to test using High Performance Liquid Chromatography (HPLC) technology?

Looks to me like future students at Greenwich High could expand on McNitt’s research and follow in her award-winning footsteps. They have a great research location, ability to survey properties within a 4 mile radius of the hives and perhaps even discover and map the places where the bees are picking up imidacloprid, down to the product name. The next test in the Greenwich High School CCD Research Program should be of the water supply, an often overlooked source of contamination - bees drink water and use it to cool the hive! Science teacher Andy Bramante may need some TA’s, too. ;) - DNR

Jim McNitt Website Screenshot

http://www.jimmcnitt.com/Site2/Blog/Entries/2009/3/13_And_the_winner_of_the_2009_Connecticut_Science_Fair_Is…..html

———————

3/13/09 - Just yesterday I posted some 2008 news about this young woman, and today I see she’s more scientist researcher than film maker! If there’s any high school that would have its own advanced Spectroscopy and Chromatography technology, it would be Greenwich High School. Lucky girl. I’m waiting for Eliza to send me the link to her research (use comment)… Congratulations! You deserve a full ride to college. (Stick with the hard sciences ;)) -DNR

Mar 12, 2008
Greenwich High student wins science competition
http://www.acorn-online.com

Eliza McNitt, a Greenwich High School junior, captured top honors at the 45th Connecticut Junior Science and Humanities Symposium for an original research project that traced the migration of pesticides through the production of southwestern Connecticut honey.

In addition to a $1,000 scholarship and letter of recognition from Gov. M. Jodi Rell, McNitt will represent Connecticut at the National Junior Science and Humanities Symposium at Orlando, FL, in May. The symposium program is sponsored by the U.S. Army, Navy and Air Force in an effort to encourage original scientific research at the high school level. Courtney Fogwell, a GHS senior, was selected as a National Symposium alternate for her project analyzing the environmental impact of artificial-turf playing fields.

Eliza and Courtney were among 13 state finalists who made oral presentations before an audience of more than 300 fellow science students, parents, teachers, and jurors at the University of Connecticut in Storrs on March 10. Both students were mentored by GHS science teacher Andrew Bramante.

“While extensive work has been done on the presence of residual insecticides on fruits and vegetables, there has been little significant scientific research on residual pesticides in honey,” Mr. Bramante said in a release. “Eliza came to me with her project on the first day of class. I almost fell off my stool when I heard it.”

Eliza says that the topic was indirectly inspired by her grandfather, a chemical engineer, who is fastidious about washing and peeling fresh produce.

“If there are insecticides on an apple,” Eliza said. “It made me wonder if they could also be present in honey.”

She found an ideal controlled research environment at the Bartlett Arboretum in Stamford, Bartlett Arboretum Mapwhich maintains an apiary in the middle of its 30 acre property. James Kaechele, arboretum education director and beekeeping specialist Andrew Cote´ made honey samples available along with detailed records of pesticide applications.

Eliza tested the arboretum honey using advanced Spectroscopy and Chromatography technology that had been donated to the GHS science program.

“I was incredibly fortunate to able to perform my own analysis,” she says. “GHS has equipment that you can’t even find in most colleges.”

Her tests revealed the presence of a component of the pesticide Neem Oil — which is widely used in organic farming. Neem Oil is made from the fruits and seeds of Neem, an evergreen tree common in India, and is not thought to be harmful to mammals, birds or bees.

The fact that Eliza found no trace of another insecticide called Imidacloprid may have implications in the search for a cause of the mysterious syndrome known as Colony Collapse Disorder (CCD) in which worker bees abruptly disappear. CCD is considered a serious threat to the pollination of food crops in the United States and Europe.

“Imidacloprid is under investigation as a contributing factor in CCD,” she said. “The fact that it is not present in the Arboretum honey could suggest that it is killing or disorienting worker bees so they cannot return to the hive.”

The topic will be something she’ll tackle in her next GHS science project. [see McNitt’s followup here]