Effects of Captan on &lt;I&gt;Apis mellifera&lt;/I&gt; Brood Development Under Field Conditions in California Almond Orchards

Everich, R.; Schiller, Chuck; Whitehead, Joanne; Beavers, M.; Barrett, Katie

doi:10.1603/029.102.0104

Cited by 22 publications

(20 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Growers of many bee-pollinated crops routinely apply fungicides during bloom, while pollinators are present [35] as there are currently no label restrictions for this action. Thus it may not be surprising that fungicides account for most of the pesticide content of pollen ( Figure 2a ).…”

Section: Discussionmentioning

confidence: 99%

High Levels of Miticides and Agrochemicals in North American Apiaries: Implications for Honey Bee Health

et al. 2010

View full text Add to dashboard Cite

BackgroundRecent declines in honey bees for crop pollination threaten fruit, nut, vegetable and seed production in the United States. A broad survey of pesticide residues was conducted on samples from migratory and other beekeepers across 23 states, one Canadian province and several agricultural cropping systems during the 2007–08 growing seasons.Methodology/Principal FindingsWe have used LC/MS-MS and GC/MS to analyze bees and hive matrices for pesticide residues utilizing a modified QuEChERS method. We have found 121 different pesticides and metabolites within 887 wax, pollen, bee and associated hive samples. Almost 60% of the 259 wax and 350 pollen samples contained at least one systemic pesticide, and over 47% had both in-hive acaricides fluvalinate and coumaphos, and chlorothalonil, a widely-used fungicide. In bee pollen were found chlorothalonil at levels up to 99 ppm and the insecticides aldicarb, carbaryl, chlorpyrifos and imidacloprid, fungicides boscalid, captan and myclobutanil, and herbicide pendimethalin at 1 ppm levels. Almost all comb and foundation wax samples (98%) were contaminated with up to 204 and 94 ppm, respectively, of fluvalinate and coumaphos, and lower amounts of amitraz degradates and chlorothalonil, with an average of 6 pesticide detections per sample and a high of 39. There were fewer pesticides found in adults and brood except for those linked with bee kills by permethrin (20 ppm) and fipronil (3.1 ppm).Conclusions/SignificanceThe 98 pesticides and metabolites detected in mixtures up to 214 ppm in bee pollen alone represents a remarkably high level for toxicants in the brood and adult food of this primary pollinator. This represents over half of the maximum individual pesticide incidences ever reported for apiaries. While exposure to many of these neurotoxicants elicits acute and sublethal reductions in honey bee fitness, the effects of these materials in combinations and their direct association with CCD or declining bee health remains to be determined.

show abstract

Section: Discussionmentioning

confidence: 99%

High Levels of Miticides and Agrochemicals in North American Apiaries: Implications for Honey Bee Health

et al. 2010

View full text Add to dashboard Cite

show abstract

“…However, limited data exist on the potential impacts of ‘inerts’ on non-target pollinators, although recent studies implicate formulation additives or adjuvants as key risk factors [52]. As one example, the toxicity of the fungicide captan to honey bee brood development was attributed to formulation ingredients other than the active ingredient alone [53]. The lack of detailed information of the usage of formulation ingredients greatly impedes appropriate risk assessment of ‘inert’ ingredient toxicity; therefore, label disclosure of the composition of pesticide formulations would facilitate this much-needed evaluation.…”

Section: Discussionmentioning

confidence: 99%

Four Common Pesticides, Their Mixtures and a Formulation Solvent in the Hive Environment Have High Oral Toxicity to Honey Bee Larvae

et al. 2014

View full text Add to dashboard Cite

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. Among these four pesticides, honey bee larvae were most sensitive to chlorothalonil compared to adults. Synergistic toxicity was observed in the binary mixture of chlorothalonil with fluvalinate at the concentrations of 34 mg/L and 3 mg/L, respectively; whereas, when diluted by 10 fold, the interaction switched to antagonism. Chlorothalonil at 34 mg/L was also found to synergize the miticide coumaphos at 8 mg/L. The addition of coumaphos significantly reduced the toxicity of the fluvalinate and chlorothalonil mixture, the only significant non-additive effect in all tested ternary mixtures. We also tested the common ‘inert’ ingredient N-methyl-2-pyrrolidone at seven concentrations, and documented its high toxicity to larval bees. We have shown that chronic dietary exposure to a fungicide, pesticide mixtures, and a formulation solvent have the potential to impact honey bee populations, and warrants further investigation. We suggest that pesticide mixtures in pollen be evaluated by adding their toxicities together, until complete data on interactions can be accumulated.

show abstract

“…Other fungicidal compounds related to captan such as captafol, folpet, and dichlofluanid were far less efficient in inhibiting chitin synthesis in vitro. Captan seems to have no adverse effects on beneficial insects such as honeybees under field conditions (Everich et al , 2009), although it (as many other pesticides) can be detected in wax, pollen, and bees (Mullin et al , 2010), and it has been reported to have toxic effects after contact and oral administration of single high doses to the orchard mason bee, Osmia lignaria (Ladurner et al , 2005).…”

Section: Chitin Synthesis Inhibitorsmentioning

confidence: 99%

Chitin synthesis inhibitors: old molecules and new developments

2012

View full text Add to dashboard Cite

Chitin is the most abundant natural aminopolysaccharide and serves as a structural component of extracellular matrices. It is found in fungal septa, spores, and cell walls, and in arthropod cuticles and peritrophic matrices, squid pens, mollusk shells, nematode egg shells, and some protozoan cyst walls. As prokaryotes, plants and vertebrates including humans do not produce chitin, its synthesis is considered as an attractive target site for fungicides, insecticides, and acaricides. Although no chitin synthesis inhibitor has been developed into a therapeutic drug to treat fungal infections in humans, a larger number of compounds have been successfully launched worldwide to combat arthropod pests in agriculture and forestry. This review summarizes the latest advances on the mode of action of chitin synthesis inhibitors with a special focus on those molecules that act on a postcatalytic step of chitin synthesis.

show abstract

Effects of Captan on <I>Apis mellifera</I> Brood Development Under Field Conditions in California Almond Orchards

Cited by 22 publications

References 5 publications

High Levels of Miticides and Agrochemicals in North American Apiaries: Implications for Honey Bee Health

High Levels of Miticides and Agrochemicals in North American Apiaries: Implications for Honey Bee Health

Four Common Pesticides, Their Mixtures and a Formulation Solvent in the Hive Environment Have High Oral Toxicity to Honey Bee Larvae

Chitin synthesis inhibitors: old molecules and new developments

Contact Info

Product

Resources

About