Brussels, 26/06/2014 (Agence Europe) - It is recognised that systemic neonicotinoid and Fipronil-based pesticides (“neonics”) kill bees but they also have a devastating effect on many other useful invertebrate species. This was confirmed by a new international scientific meta-analysis, whose results were published in Brussels on Tuesday 24 June before the forthcoming publication of the analysis.
According to the Worldwide Integrated Assessment (WIA), which will be appearing in the Environmental Science and Pollution Research journal, neonics present a high risk to honeybees and other pollinators, such as butterflies and a broad variety of other invertebrates (earthworms, for example) and vertebrates, such as birds. Exposure to these substances can be immediate and fatal, but effects can also be chronic. Long-term exposure to low non-lethal doses can also be damaging. Some of the chronic damage that can occur includes loss of sense of smell and memory, the loss of fertility, altered trophic behaviour and a decline in available food sources, including less nectar gathering from bees and reduced capacity among earth worms to dig tunnels, difficulties in flying and a greater sensitivity to disease.
In order to complete this analysis, the task force on systemic pesticides, which brings together independent scientists and advises the IUCN, carried out a review of the scientific literature available (800 publications reread by peers). It concluded that there was clear scientific proof of the damage these pesticides cause, warranting further precautions and stricter regulation on neonicotinoids and Fipronil. This could begin with plans to gradually get rid of them globally. This is likely to be received positively by those who judge the limited measures adopted by the European Commission - a partial two-year moratorium on the use of three kinds of neonicotinoids (see EUROPE 10909) - as inadequate.
Task force chairman, Dr Maarten Bijleveld van Lexmond, said that “the conclusions of the WIA are the most worrying. We can clearly see that neonics and Fipronil represent a risk to the functions and ecosystem services that go well beyond the related species concerns and which should really be drawn to the attention of government and regulatory bodies”. Dr Jean-Marc Bonmatin (CNRS, France) asserted that “we are facing a threat to the productivity of our natural and agricultural environment and its threat is equivalent of that constituted by organophosphates and DDT”.
The analysis has demonstrated that the categories of species most affected were terrestrial invertebrates, such as earthworms, which are exposed to high levels through soil and plants, to medium levels through surface water and leaching, and to low levels contained in dust the air.
The second group most affected includes pollinating insects (bees, butterflies, etc.), which are exposed to a high level of exposure through the air and plants, and to medium levels of exposure through water. Individual insects and whole populations can be affected by low or high exposure levels, which make them highly vulnerable. Aquatic invertebrates are next, such as freshwater gastropods and water fleas, which are sensitive to low and high exposure levels, as well as vertebrates, such as birds, which are exposed to medium levels through the soil, air, water and plants. It has also been found that fish, amphibians and microbes were all affected by high exposure levels or after prolonged exposure. Available scientific data is insufficient for determining whether there has been an impact on mammals and reptiles but researchers conclude that an impact on reptiles is likely.
With regard to bees, the study shows that neonics in realistic field-use concentrations damage individual navigation, learning, food collection, longevity, resistance to disease and bee fertility. With regard to bumblebees, irrefutable effects at a hive level have been observed, with exposed hives growing more slowly and producing far fewer queen bees.
Neonics are the most commonly used pestiocides in the world and are often used in the domestic treatment for preventing fleas in cats and dogs and treating termites in wooden structures. (AN)