> Despite those on BEE-L which say there are not problems in beekeeping today other than what has been throughout history


I don't know anyone who fits this description. The world is constantly changing; new and unexpected challenges face us every day. However, very early on several of us pointed out that neonics are far safer than older formulations, and that all the attention being paid them was a distraction from several other problems, which were potentially far more serious. 

Early on, we were raising the flag about the non-systemic foliar spraying of chemicals that are presumed to be non-lethal to bees, namely fungicides, antibiotics and the various adjuvants that radically increase the effects of some of these toxins. In fact, many pesticides are tested alone even though the eventual formulation is known to be far more toxic due to the actions of "non-toxic inerts."

Two years ago this was published:

The almond pollination in the Central Valley of California is the single largest pollination event in the world. Agrochemicals applied to these almond trees are therefore likely to have the greatest impact on honey bee health relative to other cropping systems. Furthermore, some pesticides – especially fungicides – are applied to almonds while the flowers are in bloom. Given that foragers visit open flowers to collect pollen and nectar, this scenario represents the greatest potential hazard to foraging honey bees in terms of exposure to agrochemicals.

We have demonstrated here, for the first time, that agricultural spray adjuvants – and organosilicone surfactants in particular – do indeed cause significant learning impairment when ingested by honey bees. Their perceived status as ‘inert’ materials that can do no harm to biological organisms should be reconsidered. Field tests will need to be conducted to confirm these results on a colony-level, as events in the laboratory do not always translate to an organism’s natural setting. 

Ciarlo, Timothy J., et al. "Learning impairment in honey bees caused by agricultural spray adjuvants." PloS one 7.7 (2012): e40848.

More recent work by Chris Mullin and James Frazier shines the spotlight on the interaction between commonly used miticides which are present in combs, and the fungicide chlorothalonil.

Recently, the widespread distribution of pesticides detected in the hive has raised serious concerns about pesticide exposure on honey bee (Apis mellifera L.) health. A larval rearing method was adapted to assess the chronic oral toxicity to honey bee larvae of the four most common pesticides detected in pollen and wax - fluvalinate, coumaphos, chlorothalonil, and chloropyrifos - tested alone and in all combinations. All pesticides at hive-residue levels triggered a significant increase in larval mortality compared to untreated larvae by over two fold, with a strong increase after 3 days of exposure.

The current study demonstrates the chronic oral and mixture toxicity of common pesticides at hive levels to honey bees at the larval stage. Most notable are the chronic larval toxicities of the fungicide chlorothalonil and its synergistic combinations with frequently used in-hive miticides, and the unexpected high toxicity of the formulation ingredient N-methyl-2-pyrrolidone. Considering the extensive detection of chlorothalonil and its coexistence with other pesticides in diverse combinations especially in hive pollen and wax, and its substantial larval toxicity alone and in mixtures shown here, the application of this and other fungicides during crop bloom cannot be presumed innocuous to pollinating honey bees. 

Zhu, W., Schmehl, D. R., Mullin, C. A., & Frazier, J. L. (2014). Four Common Pesticides, Their Mixtures and a Formulation Solvent in the Hive Environment Have High Oral Toxicity to Honey Bee Larvae. PloS one, 9(1), e77547.

If you are still reading, I would add a bit about organosilicone surfactants:

Organosilicates are not exactly new; they were developed in the 1970s, and have many uses including silicone-based sprays for waterproofing. About 10 years ago, their use as spray adjuvants for crop production was discovered. Some research suggests that the wetting properties of these surfactants are so good that they can also allow bacteria and fungi to more easily invade plants (via stomata). 

[while this does not mention insects specifically, the last sentence about allowing bacteria and fungi to penetrate is most troubling]

PLB 

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