01
Oct
(Beyond Pesticides, October 1, 2019) Commonly used fungicides induce trophic cascades that can lead to the overgrowth of algae, according to research published in the journal Chemosphere. While the current process for regulating pesticides in the U.S. focuses on the acute toxicity of pesticides, and may consider some chronic impacts, real world complexities as described in the current study are not reviewed. This gap in our assessment can lead to significant adverse effects not just on individual species, but entire ecosystems. Researchers investigated how fungal parasites known as chytrids control the growth of phytoplankton. While some strains of chytrids are notorious for their impact to frog species, some do in fact provide important stopgaps within ecosystems. “By infecting cyanobacteria, parasitic fungi limit their growth and thus reduce the occurrence and intensity of toxic algal blooms,” says IGB researcher Ramsy Agha, PhD, co-author the study. “Whereas we usually perceive disease as a negative phenomenon, parasites are very important for the normal functioning of aquatic ecosystems and can — as in this case — also have positive effects. Pollution by fungicides can interfere with this natural process,” the researcher adds. The agricultural fungicides tebuconazole and azoxystrobin were tested on chytrid-infected toxic bloom-forming […]
Posted in Agriculture, Azoxystrobin, Fungicides, tebuconazole, Uncategorized | No Comments »
30
Nov
(Beyond Pesticides, November 30, 2018) A study published this month in Science of the Total Environment reveals numerous pesticide residues persisting in soil, harming the viability of agricultural lands and increasing risk of off-site contamination. Funded by the Horizon 2020 programme of the European Commission, researchers from the European Diverfarming project at the University of Wageningen in the Netherlands suggest nations urgently reevaluate conventional land use and inputs including water, energy, fertilizers, machinery and pesticides. Researchers decrying the lack of soil protection policies endeavored to determine which pesticides had the highest soil persistence and toxicity to non-target species. Three hundred seventeen surface soil samples were analyzed from 11 European countries. Selected countries were those with the largest amounts of active agricultural land, characterizing six distinct cropping systems. Sampled soils purposefully represented different soil properties and were taken from crops with the highest pesticide use per hectare. Samples were then analyzed for the concentration of 76 pesticide residues. These 76 pesticides were selected as being most often applied on conventional crops. Eighty-three percent of samples contained varying degrees of pesticide residues, with 25 percent showing one pesticide residue and 58 percent showing mixtures of two or more. Only 17 percent of […]
Posted in Biodiversity, contamination, Contamination, DDT, Disease/Health Effects, Fungicides, Genetic Engineering, Glyphosate, International, Persistence, Pesticide Residues, tebuconazole, Uncategorized | No Comments »
30
Jul
(Beyond Pesticides, July 30, 2013) A recent study published in Environmental Toxicology and Chemistry found levels of pesticide contamination from agricultural drift in Pacific Tree frogs in remote mountain areas including national parks. The study supports past research on the pesticide transport through atmospheric dust and rain. To conduct the study, researchers collected Pacific Chorus frogs, as well as water and sediment samples, from seven ponds ranging from Lassen Volcanic National Park at the northern most location of Central Valley to the Giant Sequoia National Monument. The samples were tested for 98 types of pesticides, traces of which were found in frog tissues from all sites. Two fungicides, pyraclostrobin and tebuconazole, and one herbicide, simazine, were the most frequently detected compound. This was the first time these compounds have ever been reported in wild frog tissues. According to the study, chemical concentrations are often higher in the frog tissue than the environment. This happens as frogs store up small exposures over time, allowing pesticides to bioaccumulate in their bodies. Exposure to pesticides can decrease frog’s immune system and increase their risk of disease. Continual pesticide exposure has led to dramatic declines in amphibian populations. Amphibians are considered the most threatened […]
Posted in Agriculture, California, Pesticide Drift, simazine, tebuconazole, Water, Wildlife/Endangered Sp. | No Comments »
17
Nov
(Beyond Pesticides, November 17, 2010) Researchers with the U.S. Geological Survey (USGS) have found a dozen agricultural fungicides in the waters and sediments downstream of farms and orchards in western states. Presented November 8, 2010 at the annual meeting of the Society of Environmental Toxicology and Chemistry (SETAC) in Portland, Oregon, the findings represent the first such data on fungicides in the western U.S. Farmers routinely use fungus-killing compounds to spray or dust food crops, such as strawberries, corn, and soybeans. Some crops receive up to a dozen doses per growing season. Nationwide, fungicide use has risen considerably since the 1990s, reaching 350 million pounds in 2001. However, the environmental prevalence and effects on wildlife and ecosystems, particularly of newer fungicides, are poorly understood, says Kathryn Kuivila, PhD, of the USGS California Water Science Center. Environmental monitoring programs monitor concentrations of few or no fungicides, she notes. The study entitled, “Occurrence of Azoxystrobin, Propiconazole, and Selected Other Fungicides in US Streams, 2005—2006,” documents the occurrence of fungicides in select U.S. streams soon after the first documentation of soybean rust in the U.S. and prior to the corresponding increase in fungicide use to treat this problem. Water samples were collected from […]
Posted in California, Idaho, Metalaxyl, Myclobutanil, Propiconazole, tebuconazole, Tebuthiuron, Water | No Comments »
