In response to Waldemar's questions: The diversity of pesticide residues has been about the same. The types of chemicals change a bit with the years and regions. We still see residues of DDT, DDD, and DDE, although these are very slowly dropping off. A few weeks ago, I sent the following to our colleagues on the CCD Working Group: CCD Working Group: I managed to free up a few minutes and looked up some of our previous pesticide work, as well as those of some of our colleagues. We collected hundreds of bee and pollen samples at Aberdeen Proving Grounds and at off-site areas north of Baltimore in the late 1990s, early 2000s. We found 4,4'-DDT, 4,4'DDE, 4,4'-DDD, aldrin, gamma-chlorodane dieldrin, alpha-BHC, beta-BHC, delta-BHC, gamma-BHC (lindane), endosulfan sulfate, endrin, endrin aldehyde, heptachlor, heptachlor epoxide, and various PCBs (aroclor 1260, 1248, 1254). I should note: Anderson, J.F.; Wojtas, M.A. (1986) also found PCBs in bees, as well as lots of other pesticides in samples from Connecticut counties. More often than not, in the Aberdeen/Baltimore area, we found detectable levels of pesticides in most bee samples, and sometimes in pollen. Heptachlor was seen in both bees and pollen and was often the highest concentration (ug/kg dry weight). 299+ 360. PCB concentrations often exceeded those of pesticides. In fact, over the last 20 years, we have been unable to find a bee sample that does not contain readily detectable levels of PCBs. Not surprisingly, DDT and its breakdown products remain readily detectable in many soils. In Europe, the Italians have conducted some long-term and wide area sampling for pesticides. Porrini et al., in a four-year pesticide monitoring study (1983-86), found 70.8% of the samples tested positive for Dithiocarbamates, 15.3% for dimethoate, 14.7% for parathion, 11.9% for azinphos-methyl, 11% for carbaryl, 10.4% for methyl parathion, 7.2% for endosulfan, 7.2% for omethoate, and 2.4% for methamidophos. The Italians noted that the dithocarbamates, used as fungicides, are considered to be of low toxicity to bees, however, they were the most widespread chemicals in dead bees in cultivated fields. In recent litigation concerning pesticides and bees in the U.S., for which we consulted to several different beekeepers, sevin xlr and furadan were allegedly involved in several severe bee kills. The residue levels that we've seen would indicate poisoning events by these chemicals in the cases that we saw. Finally, we've had some recent correspondence with USGS that indicates that pyrethroid usage is on the increase in California, and is showing up in more and more water samples. Finally, whereas pesticide residues are common in bees, our work has shown that other environmental chemicals occur in bee colonies, sometimes at toxic levels. For example, heavy metals and fluoride in industrial regions. Among the volatile and semi-volatile organics, chemicals like benzene and styrene stand out in terms of concentrations and/or prevalence. We look forward to learning how the PSU/USDA results compare with these studies. Jerry ************************************** Get a sneak peek of the all-new AOL at http://discover.aol.com/memed/aolcom30tour ****************************************************** * Full guidelines for BEE-L posting are at: * * http://www.honeybeeworld.com/bee-l/guidelines.htm * ******************************************************